eChapters

INTRODUCTION
A Primary Processing Centre (PPC) is a facility that offers essential infrastructure for the initial processing of agricultural produce, including grading, sorting, packaging, and storage. These centers are strategically located near production zones within raw material catchment areas and are supported by Collection Centers (CCs) in nearby villages.
The establishment and efficient management of a Primary Processing Centre (PPC) play a crucial role in enhancing the value of raw agricultural products, improving their marketability, and minimizing post-harvest losses. A welloperated PPC integrates modern processing technologies, optimized resource utilization, and streamlined logistics to ensure high-quality output and long-term sustainability. Advanced processing methods such as drying, milling, juicing, and canning help maintain product quality and nutritional integrity while reducing waste. Additionally, a robust management framework is essential for supervising operations, implementing quality control measures, and maintaining an efficient supply chain that connects local farmers to the processing facility. The effectiveness of a PPC extends beyond technical efficiency, as it also fosters community empowerment through job creation, skill enhancement, and active participation, thereby contributing to both economic development and sustainable agricultural practices. By harmonizing these elements, a PPC serves as a critical hub for agricultural progress, granting farmers improved market access, decreasing reliance on unprocessed exports, and generating value-added products that align with consumer demand.
The manufacturing and management of a Primary Processing Centre (PPC) play a crucial role in transforming raw agricultural produce into value-added products that enhance marketability, reduce post-harvest losses, and improve farmers’ income. A well-established PPC serves as a key

INTRODUCTION Snacks manufacturing involves transforming various ingredients into chips or other types of snacks. These snacks are often enhanced with added flavors, boosting their taste and appealing to buyers seeking a quick and satisfying bite. Ready-to-eat snacks come in a wide array of flavors and varieties, with snack manufacturers in India constantly introducing new options.
As per the India Snacks Market Forecast, based on surveys of snack companies and consumer preferences, the Indian snack market is projected to surpass Rs 1 billion by 2024, creating more opportunities for newcomers in the industry. The food sector has become a highly profitable industry, fostering the growth of innovative food processing units. Snack manufacturing companies like Kiwi Foods are leading the way by offering new, exciting products that are quickly gaining popularity.
Food is essential for energy, but sometimes, heavy meals aren’t the best option, and snacks serve as a perfect alternative. Whether it’s during tea time or a quick bite during a hectic workday, snacks are a versatile food choice for any occasion. The market offers a diverse range of options, from classic salted chips to unique varieties like pop pasta and masala corn. Snack manufacturers in India cater to the evolving tastes and preferences of consumers, providing a wide range of delicious snack choices.
PROCESSING SNACK FOODS
Snack foods can also be grouped according to the food processing method used to produce them, even though people typically divide them into two categories: sweet and salty. Simple extrusion is used to create the first-generation snacks; no additional processing is required. This category includes snacks like popcorn, dried fruit, potato chips, and nuts

Introduction
At the moment, liposomes, which are tiny bubble-like structures made of phospholipid bilayers, are an important part of all drug transport methods. Their unique ability to hold medicinal chemicals that both like and don’t like water is what makes them stand out. These molecules’ ability to change forms is very important for making different medicines more bioavailable, stable, and effective (Shah et al., 2020; Wagner and Vorauer-Uhl, 2011). Since Alec D. Bangham first found liposomes in the 1960s, they have gone from being simple experimental models to highly advanced carriers that are now used in both clinical and business settings. Liposome production has changed over time from simple lab methods to complex systems used on a commercial scale. At the moment, these methods can make liposomal formulations that are of high quality and consistently good traits (Alavi et al., 2022; Wagner et al., 2006). It is very important to know how to control the physicochemical qualities of liposomes during the manufacturing process. This includes things like size, charge, lamellarity, and how well they encapsulate (Mozafari et al., 2005; Watwe and Bellare, 1995). It is important to know the qualities of liposomes in order to figure out how they act in biological systems, like how fast drugs are released, how long they stay in circulation, and how they spread throughout the body. What method is used to make liposomal pharmaceutical compositions has a big effect on how safe and useful they are. Over the years, many methods have been developed to make liposomes with specific properties that are useful for their purpose (Sorgi and Huang, 1996; Patil and Jadhav, 2014). One of the first and easiest ways to make liposomes was through thin-film hydration. It was mostly used in places where study was being done. “Thin-film hydration” is the process of an organic liquid evaporating after lipids dissolve in it, which makes a thin film (Redziniak et al., 2017). After that, a watery phase is added to the film, which causes multilamellar vesicles (MLVs) to form. This method is easy to use and works well for smallscale applications, but it often creates liposome populations that aren’t all the same size or level of encapsulation. In order to get around these problems, methods like sonication and extrusion are used to make liposomes that are smaller and more uniform (Vemuri et al., 1990).
There is a method called “sonication” that can be used to efficiently change larger liposomes into smaller unilamellar vesicles (SUVs). The size of liposomes can be reduced very well with this method, which is known for being one of the first to do so. With this method, liposomes with diameters generally smaller than 100 nm can be made very efficiently. Because of this, these liposomes work well for many cellular purposes. Despite this, sonication could create heat and mechanical forces that could damage the structure of the liposome membrane or make it less stable for molecules that are particularly fragile. Improving the sonication settings is necessary to find the best balance between making the liposomes smaller while still protecting the inside parts (Liu and Meng, 2021).
An effective way to make liposomes with a precise and uniform size distribution is through extrusion. A pressure-based method can let liposomes pass through

Soil fertility and crop production can be maintained only by efficient and judicious management of nutrients addition to the soil from external sources. Of the two sources most widely used all over the world, one is organic in nature- the organic manures, simply called manures, and the other comprises the synthetic or naturally occurring chemical fertilizers, simply called fertilizers. A brief account of manures is described hereunder:

The word manure came from Middle English manuren meaning to cultivate land, and initially, from French word manoeuvre meaning hand work alluding to the work which involved manuring land. The term manure originally meant that which was worked by hand (Fr. manoeuvre), but gradually, came to apply to any process by which the soil peroperties could be improved. Prominent among such processes was that of directly applying manure to the land, manure in this sense being what is now called farmyard manure or dung, the excreta of farm animals mixed with straw or other litter. Ronald Fisher seems to have used the word manure systematically for what we would call fertilizer today.

Uses of Manure

Manure has been used for centuries as a fertilizer for farming since it is rich in nitrogen and other nutrients, which facilitate growth of the plants. Liquid manure from pig or hog operations is usually knifed (injected) directly into the soil to reduce the unpleasant odours. Manure prepared from hogs and cattle is spread on fields using a manure spreader. Due to the relatively lower level of proteins in grasses, which herbivores eat, cattle manure has a milder smell than the dung of carnivores, e.g., elephant dung is practically odourless. However, due to the quantity of manure applied to fields, odour can be a problem in some agricultural regions. Poultry droppings are harmful to plants when fresh but after a period of composting are valuable fertilizers.

The dried manure of animals has been used as fuel throughout history. Dried manure (usually known as dung) of cow was and still is an important fuel source in countries such as India, while camel dung may be used in treeless regions such as deserts.

Introduction Livestock plays a vital role in rural economy. Apart from milk, which is a significant economic contributor, efficient use of livestock resources and byproducts like Manure/dung in biogas systems can help generate localised clean cooking energy for rural masses. At the same time, biogas spent slurry; a by-product of biogas plant is a potential source of major and micronutrients besides organic matter. Its proper utilisation after processing has a vast potential in meeting the nutrient requirement of the crops and thereby reducing use of chemical fertilizers besides providing sustenance to soil health. It is estimated that about 443.5 lakh tonnes of solid bio-slurry could be made available from dairy animals. This bio slurry can be processed to produce bio fertilizers which can meet the India’s requirement of NPK and micronutrients (Fe, Mn, Zn, Cu) by about 4.5% and 0.4% respectively. Vermicomposting is the best technique to convert livestock waste into a resource. In India livestock manure is managed basically in three ways:

A. Majority cases dung/manure excreted by livestock are removed and dumped into heaps nearby cattle sheds. The heaps remained for some time when they get converted into manures, which are spread subsequently in the fields as an organic matter.

B. Manure/dung is utilized for energy purpose in village level where the dung is made into small cakes and dried and later on used as a fuel for cooking purposes. This is a great wastage of organic matter which needs to be utilized or managed in other ways so that both the energy and manure can be obtained from the livestock waste.

C. This method of manure utilization is popularized both by central and state government through bio-gas plant where manure is used for the production of methane under anaerobic (lack of oxygen) conditions. The methane gas is used for cooking purpose as well as the slurry after methane extraction is used as farm manure. This management and technique reduce methane emission in environment utilized the methane for cooking purpose and at the same time the valuable waste is utilized as a farm manure.

Manure can be a) solid manure, feed waste, soiled bedding, etc. and b) liquid – urine and detergent Water. Ideally, solid manure is usually collected and removed twice daily. India has about 535.78 million livestock and the amount of production of animal waste amounts to about 3 million tons per year. Together farm-level livestock waste includes manure, urine, placenta, bedding,Feed waste, milk house waste etc. These animal wastes are the biggest source of harmful gases, harmful pathogens and odors and therefore public health and environmental concerns. Livestock waste contains many useful substances components that, if recycled effectively, can be used as fertilizer for crops, food for animals. Economic savings are the biggest benefit of waste management achieved through improvements in human health and the environment, leading to higher productivity, lower medical costs, etc ultimate increase in farmers’ income. The animal waste is a major source of harmful gases, harmful pathogens, etc Odor;

Growth is the development of a plant as a whole or of a specific organ. Besides the genetic factors, the environmental factors grouped as climatic factors and soil factors influence plant growth. The supply of mineral nutrient elements to the plants is discussed in this chapter.

A complete analysis of plants detects large number of elements. But only certain elements are essential. An element is said to be essential if the plant cannot complete its life cycle without it, and if the malady (deficiency) that develops in plants in its absence can be remedied only by that element.

Earlier 16 elements were considered as essential for plant growth. They are carbon, hydrogen, oxygen, nitrogen phosphorus, potassium, calcium, magnesium, sulphur, iron, manganese, zinc, copper, molybdenum, boron and chlorine. Recently, sodium, cobalt, vanadium, silica, selenium, gallium, aluminium and iodine are added to the above list. One or the other of these elements (recently added) has been found to be essential for a particular species of plants.

Carbon dioxide, water and molecular oxygen are the forms in which C., H and O are assimilated by plants. Others are taken up by plants from the soil. Nutrient uptake by plants accounts for about 10 percent of total dry weight of crops, the remaining percentage being water. The chemical symbol and the ionic forms in which the essential elements are absorbed by the plants are as follows.

Manures are the plant and animal wastes that are used as source of plant nutrients. They release nutrients upon their decomposition.

Bulky organic manures contain small percentage of nutrients and they are applied in large quantities. e.g,. farmyard manure, compost, green manures.

Introduction

Manures are obtained from the plant residues, green manure, compost and animal wastes that are used as source of plant nutrients. They release nutrients after their decomposition. They essentially function as sustenance to the crops. They help in the proper cultivation of crops. The addition of manure enables the soil to hold more water. Organic manures have acids that dissolve the nutrients in the soil and make them available to the plants. manures can be grouped into bulky organic manures and concentrated organic manures. Brief dissection about manure given blow flow chart.

Bulky Organic Manure

Bulky organic manures are those materials of plant and animal origin, which contain small percentage of nutrients when added to the soil have tendency to decrease bulk density and to increase soil volume, thus providing better physical conditions for plant growth especially in coarse textured soils and also provide essential nutrients in smaller quantities than the chemical fertilizers. Characteristics of bulky organic manures:

Plants requires a number of nutrients for their growth and reproduction, of which six are primary in nature and they are,

1. Carbon - Plants are taking carbon from the air and soil
2. Hydrogen from water
3. Oxygen from water and air
4. Nitrogen from soil and it helps plants to synthesize protein for their growth they need to produce new tissues. Nitrogen is often in shortage in soil for the plants, and plants will try to take as much available from the soil at the same time too much of nitrogen will help the foliage growth and but not the setting of flowers and fruits.
5. Phosphorus stimulates root growth and helps the plants set flowers and seeds. Organic matter and activity of soil organisms increases the availability of phosphorus.

The word “Manure” is originated from the French word “Manoeuvrer” which refers to “work with soil”. The word Manure is also originate from Latin word “Manu” (hand) and operate (to work). Manures are the substances which are organic in nature, capable of supplying plant nutrients in available form, bulky in nature having low analytical value and having no definite composition and most of them are obtained from animal and plant waste products. Formerly, the word in use was “Dung ”in English (at present fertilizer).

Manuscript speaking is a public speaking method where a speaker delivers a pre-written speech word-for-word from a script. This style emphasizes precision and accuracy, making it ideal for contexts where exact wording is crucial, such as political addresses, legal declarations, academic presentations, and scientific reports. Commonly used in formal or high-stakes scenarios, manuscript speaking ensures consistent and accurate content delivery. However, it requires skillful execution to maintain audience engagement and avoid a monotonous or mechanical delivery.
Understanding Manuscript Speaking
Manuscript speaking is unique because the speaker relies entirely on a prepared text. This method ensures that every word, fact, and statistic is presented as intended, leaving little room for error. It is commonly used in:
1. Political Speeches: For accuracy in official addresses or statements.
2. Legal Proceedings: Where exact language is critical.
3. Scientific Presentations: To ensure technical accuracy.
4. Media Broadcasts: In scripted news delivery.
Key Components of Effective Manuscript Speaking
Mastering manuscript speaking involves more than just reading a script. It requires a balance of precise content, engaging delivery, and audience connection. Here are the key components that contribute to effective manuscript speaking:
1. Content Preparation
• Clarity and Structure: The script should be well-organized, with a logical flow of ideas.
• Audience-Centric Language: Use language that resonates with the audience’s knowledge level and interests.
• Highlighting Key Points: Ensure important ideas stand out with clear emphasis in the text.

Introduction

Fish and the aquaculture products contribute a significant amount of animal protein to the diet of the people worldwide. Being highly nutritive they serve as valuable food supplement in diets lacking essential vitamins and minerals. Besides its role of food security, fish is a source of income for millions of people around the World. Though the trade is not prominent at Global level, in some countries its contribution to foreign currency earning is vital to the National Economy. India has a coastline measuring 7500 km and important aquaculture country in the World. Being the home for more than 10% of the global fish biodiversity, the country ranks third in the World in the total fish production with an annual fish production of about 6.4 million tones. Constituting over the 1% of the GDP, fisheries contributes to 5.3% of the agricultural GDP. The estimated foreign earning for the year 2006 was US$ 1365 million.

ABSTRACT

The purpose of this paper is to map the diversity of Formicoidea, richness and habitat preferences with respective to the different forest cover, classified based on the NDVI from LANDSAT TM imagery with the help of remote sensing and GIS. The study is carried out in Sirumalai hills region of Dindigul District, Tamil Nadu state, India recorded a total of 26 species with 15 genera belonging to four sub-families by a taxonomical basis. The NDVI based forest classification results that the area has disturbed dry deciduous forest (SA), undisturbed dry deciduous forest (SB), disturbed mixed deciduous forest (SC), undisturbed semi evergreen forest (SD), undisturbed grassland (SE) and undisturbed dry evergreen forest (SF) types of forest covers. The results of diversity studies, statistical analyses and field study reveals that the tropical semi evergreen forest and tropical dry evergreen forest have yielded more number of species, genera than the mixed deciduous forest and dry deciduous forest which are most disturbed by human beings in establishment of estates, management strategies by the government and land use by the local farmers.

ABSTRACT

Mapping and exploration of iron ore deposits in parts of Salem District is carried out based on the detailed field work and the interpretations of IRS-1C PAN data in the scale of 1:12,500 and aerial photographs (NRSA, Scale 1:4,000). The study results that the major rock types of the study area are banded magnetite quartzite, garnetiferous pyroxene granulite, amphibolite, garnetiferous pyroxenite, charnokite, talc tremolite, actionalite and dunite rocks. The Banded Magnetite Quartzite’s (BMQ) occur as enclaves within the hornblende gneisses at several parts of the study area. Topographically, the rocks constitute small low-lying linear ridges at some places it is found to be closely associated with garnet pyroxene granulites. A remarkable feature about the mode of occurrence of magnetite quartzite is its linear nature and the physical form, which could be described as a “Band”. All the bands possess an ENE-WSW strike and the dip is found to be steep (above 70 degrees) towards north. The rock in the hills of Godumalai, Vellalagundam, and Singipuram are highly deformed and contact with garnetiferous pyroxene granulite and hornblende gneisses. In hand specimen, the magnetite quartzite rock exhibits fine banding. In general no variation in grain size or thickness of banding could be seen megascopically. However, occasional increase in size of magnetite might be possible as seen from the coarser magnetite pebbles strewn in the channels of the area. There are two types of folds observed namely F1 and F2. The axial plane trace of the F1 varies in trend from WNW-ESE to WSW – ENE. The joints are traced in the directions of NNW-SSE to NNE – SSW and WNW – ESE to ENE-WSW. The interpretation of lineaments shows their trend directions of NNE-SSW, NE-SWand NNW-SSE. The above said work has carried out through detailed field work and interpretations using by IRS-1C PAN data in the scale of 1:12,500 and aerial photographs of NRSA, in the scale of 1:4,000 for the study area.

ABSTRACT

With the increasing use of ground water for various activities, the fast decline in groundwater takes place. In order to prevent the aquifers from fast depletion, the ground water recharge is necessary. This study attempts to identify the favourable areas for groundwater recharge and suggest suitable recharge structures toaugment the aquifer system of the study area using Remote Sensing and GIS. The various thematic maps such as Geomorphology, Geology and lineaments, Soil, Slope, Land use, Drainage, Runoff, Depth to weathered zone, Groundwater level fluctuation and Water quality are used in the analysis. The favourable areas for groundwater recharge have been categorized into highly favourable, moderately favourable, less favourable and poor. To delineate areas favourable for recharge zone various themes are interpreted. The identification of ground water recharge zones for the study area is useful for improvement of water quality, quantity and better augmentation & management of Groundwater recharge.

Soil map is a map showing diversity of soil types and its properties such as pH, texture, organic matter and depth of horizons in the area of interest obtained as the end of soil survey. Generally, soil maps are used to simply identify soils and their properties, but are sometimes required for more specific purposes, such as the suitability of soils for a particular crop, suitability for irrigation, erosion risk and many other specific needs or environmental threats.

Soils fulfil many functions important for agriculture, forestry and the management of soil resources and natural hazards. The functionality of soils depends on their properties; hence, accurate and spatially highly resolved maps of basic soil properties such as texture, organic carbon content and pH for specific soil depth are needed for the sustainable management of soils. The surface soil organic carbon (SOC) concentration is a useful soil property to map soils, interpret soil properties, and guide fertilizer and agricultural chemical applications.

Traditionally farmers apply fertilizers, chemicals and other crop production inputs to optimize the production of the field as a whole. This results in application of over application of inputs and low inputs in certain locations of the field because of variation in field characteristics including soil organic carbon, soil texture, soil nutrients, field topography, and other properties. In addition, uniform applications may increase the chances of pollution of the environment due to excess application in some field area. Precision farming technology has been shown to optimize application rates if the variation of field characteristics can be used to guide the application rate of crop-production inputs. The organic carbon concentrations of surface soil have been used to spatially vary the application rate of some crop-production inputs. The surface soil organic carbon concentration affects the activity of many herbicides, influences plant-available nitrogen and also affects the soil’s ability to adsorb plant nutrients. Knowing its concentration may therefore be useful, especially if its spatial distribution could be determined accurately and for low cost.

Genetic Mapping

Perhaps one of the most powerful applications of markers is genetic mapping. This technology allows researchers identify markers located within or very close to genes of interest. With this it is possible to trace these genes through generations of crosses.

If the trait in question is complex and multigenic, mapping will also be of tremendous help to dissect the various genes or loci that contribute to the overall characteristic. Determining the amount of impact each locus delivers is a process called Quantitative Trait Loci or QTL mapping.

1. Introduction

Electronic theses and dissertations (ETDs) are a great resource for scholars in academic institutions. They assist academics in comprehending the study carried out in prior years. When study results are made accessible on an open access platform, they are extensively utilized for further inquiry and teaching purposes. Theses and dissertations need to be made publicly available so that the users can get access to it. So, the emergence of Shodhganga proves to be very useful to the students, researchers, faculties and all other users (Vijayakumar and Vijayakumar, 2007). A significant number of doctorate research projects are now being conducted worldwide in several fields within the natural sciences. Bibliometrics focusses on analyzing the attributes of published literature, such as the distribution of literature on different subjects, statistical examination of content kinds, references, citations, and co-citations within and across fields (Pritchard, 1969). Davarpanah and Aslekia (2008) conducted bibliometric research on PhD theses, however these investigations were often limited to a certain university or department. Shodhganga serves as a digital archive for freely accessible whole texts of Indian electronic theses.

Marburg virus (MV) disease was named after the West German town where the largest outbreaks of human infection was reported. It is also known as Vervet monkey or green monkey disease as monkey species introduced the disease in Europe. Marburg disease virus was reported in 1967 in Frankfurt-on-Main and Marburg, West Germany and Belgrade, Serbia in vaccine factory workers who came in contact with blood, organs or cell cultures of African green monkeys. Ebola and Marburg hemorrhagic fevers are severe zoonotic diseases seen not only in humans but also in non-human primates. Most species of Ebolavirus and the only known species of Marburg virus occur in Africa. Primates are infected sporadically from an unknown source probably bats. Humans seem to become infected directly from bats in caves, as well as when they, come in contact with tissues from infected apes and other species. Once the virus has entered the population, it can spread from person to person. Some epidemics affect hundreds of people. Although the mortality rate varies, 90% case fatalities have been reported in the most pathogenic viruses. No vaccine is available and the only treatment is supportive. Epizootics in gorillas and chimpanzees are equally serious, and appear to threaten the survival of these species in the wild. Other wild mammals including duikers also seem to be killed during outbreaks. One species of Ebolavirus, Reston Ebolavirus, occurs in the Philippines. Until 2008, this virus was known only as an infection of nonhuman primates. It does not appear to be a human pathogen; although some people in contact with this virus have seroconverted, they remained asymptomatic. In December 2008, Reston ebolavirus was discovered in pigs during an unusually severe outbreak of porcine reproductive and respiratory syndrome (PRRS) in the Philippines.

Etiology: Ebola and Marburg hemorrhagic fever are caused by members of the genera Ebolavirus and Marburgvirus, respectively. These viruses are the only members of the family Filoviridae. The genus Ebolavirus contains four recognized species: Zaire ebolavirus (formerly Zaire Ebola virus), Sudan ebolavirus (formerly Sudan Ebola virus), Ivory Coast ebolavirus (formerly Cote d'Ivoire Ebola virus) and Reston ebolavirus (formerly Reston Ebola virus). At least 13 strains of these viruses have been identified. A fifth species, tentatively named Bundibugyo ebolavirus, was isolated from a recent outbreak in Uganda. Marburg virus contains a single species, Lake Victoria Marburgvirus (formerly Marburg virus). Six strains of Lake Victoria Marburgvirus had been recognized as of 1990; at least nine genetically distinct strains were identified from a more recent outbreak in the Democratic Republic of the Congo. Marburg virus contains ssRNA as genome. The virion is highly pleomorphic and measures 80 nm in diameter and 700-1000 nm in length. Filoviruses can be destroyed by autoclaving. Treatment with sodium hypochlorite (1:100 dilution of household bleach) or standard hospital disinfectants can also be used. Ebolaviruses are reported to be susceptible to 2% sodium hypochlorite, 2% glutaraldehyde, 5% peracetic acid and 1% formalin. These viruses can also be inactivated by ultraviolet light, gamma irradiation, 0.3% betapropiolactone for 30 minutes at 37°C (98.6°F), or heating to 60°C (140°F) for 1 hour. Marburgvirus is susceptible to 1% sodium hypochlorite, 2% glutaraldehyde or formaldehyde, ultraviolet light and heat.

Abstract

The unique characteristics of mare’s milk help to prevent many chronic diseases. The health beneficial properties of this milk is even acknowledged since ancient time and this milk is being successfully used as medicated food against a wide range of chronic diseases. The merits of mare’s milk has also been noted by the cosmetic and pharmacy industries. Lastly, considering many health beneficial effects of this milk, attempt should be made to augment the production and popularization of mare’s milk. In this chapter different aspects of mare’s milk has been pointed out in different sections and subsections.

Introduction

Globally, 16.9% of milk consumed by humans comes from species other than cattle. Non-cattle milk is linked more to territories than cows’ milk: sheep in the Mediterranean basin, horse in Central Asia, yak in Himalayas, camel in desert regions. The domestic equid species (horse and donkey) belong to the taxonomic order Perissodactyla, family Equidae and genus Equus. The nutritional and therapeutic properties of horse (Equus caballus) milk have been known since ancient times according to the historian Erodoto (V century BC). Although horses are of minor importance for milk production in comparison with cows, buffalo, sheep and goats, they have been traditionally important dairy animals in Mongolia and in the southern states of the former Soviet Union, e.g., Kazakhstan, Kyrgyzstan and Tajikistan. Aristotle (322 BC) reported the existence of a dairy product in Mongolia that processed mare’s milk to transform it into a fermented product with an alcohol content of 3% and Herodotus also reported something very similar performed by the Scythians;

Marek’s disease is a herpesvirus-induced neoplastic disease of chickens characterized by infiltration of various nerve trunks and/or organs with pleomorphic lymphoid cells. Marek’s disease is world wide in distribution. Marek’s Disease has been named after Josef Marek who published the disease in 4 roosters in 1907.

Occurrence

In chickens only, however turkeys and quail have limited susceptibility. Lesions similar to MD have been seen in pheasants, ducks, pigeons, geese, canaries, budgerigars, swans and great horned owls. However, aetiology for lesions in these species has not been proved. It may appear at 3-4 weeks but usually after eight weeks, with major losses from 12-25 weeks. Morbidity and mortality varies depending on the virulence of MDV.

In India marigold is one of the most commonly grown flowers and used extensively on religious and social functions in different forms. Because of their ease in cultivation, wide adaptability to varying soil and climatic conditions, long duration of flowering and attractively coloured flowers of excellent keeping quality, the marigolds have become one of the most popular flowers in our country. Flowers are sold in the market as loose or as garlands. Due to its variable height and colour marigold is especially use for decoration and included in landscape plans.

1) Botrytis Gray Mould
Diagnostic Symptoms
• Appearance of a gray, fuzzy mold leaves, stems and on flowers of or plants. Also called, “gray mold”.
• Spotting or blight on leaf and flower stem lesions, and dieback.
• Flower parts become necrotic and die(Fig-1).
Etiology
Domain : Eukaryota
Kingdom : Fungi
Division : Ascomycota
Class : Leotiomycetes
Order : Helotiales
Family : Sclerotiniaceae
 

Bud caterpillars : Helicoverpa armigera : Noctuidae

Eggs are laid singly on young buds.  Larvae feed on developing flowers by damaging florets. They can also eat the leaves.

Leaf webber : Phycita sp. : Phycitidae

Larvae of Phycita sp. feed on heads of buds and flowers.

Marigold is one of the easiest annual flowers to cultivate, having wide adaptability. Flowers are attractive, have good keeping quality with a wide spectrum of colour, shape and size. They produce marketable flowers in a short time and are used widely for religious and social functions as well as for garden display. 

Importance and Uses

 Marigolds are sold as loose flowers, as cut flowers and widely used for various decorations and garland making. They are also excellent landscape plants widely used for bedding purpose, in herbaceous borders and can also be grown in pots. French marigolds, being dwarf, are suitable for hanging baskets, rockeries, edging and window boxes. In fact, marigolds rank next only to jasmine in popularity in South India 

Marigold (Tagetes spp.) an annual flowering plant belongs to family Asteraceae, alternately known as Compositae. The word “marigold” means “Mary’s Gold” and refers to the “Virgin Mary”. However, word “Tagetes” named after the Etruscan God “Tages” who supposedly emerged from the earth as it was being ploughed and was imbued with the power of divination. Cultivated species include Tagetes erecta commonly referred as African marigold and Tagetes patula as French marigold. Marigold commonly propagated by seed and cutting is a leading loose flower of India. Selection of variety is favoured by a higher proportion of double inflorescences.

Marigold (Tagetes spp.) an annual flowering plant belongs to family Asteraceae, alternately known as Compositae. The word “marigold” means “Mary’s Gold” and refers to the “Virgin Mary”. However, word “Tagetes” named after the Etruscan God “Tages” who supposedly emerged from the earth as it was being ploughed and was imbued with the power of divination. Cultivated species include Tagetes erecta commonly referred as African marigold and Tagetes patula as French marigold. Marigold commonly propagated by seed and cutting is a leading loose flower of India. Selection of variety is favoured by a higher proportion of double inflorescences.

ORIGIN AND DISTRIBUTION

Origin of marigold is central and South America especially Mexico (Kaplan, 1960). Bailey (1951, 1963 and 1976) reported that marigold is a native to Arizona and Mexico to Argentina.

During early 16^th century it spread to various parts of world from Mexico. African marigold (Tagetes erecta) first reached Spain and from there it become popular as rose of Indies in Southern Europe. Major work on improvement and cultural practices on marigold have been done in USA, Switzerland, France and Germany. In India, marigold was introduced by Portuguese and it became popular and spread quickly because of its wide adaptability to varying climatic and soil conditions. Marigold is well distributed in different states and union territories of India (Singh, 2006).

SPECIES

Earlier, Rydberg (1915) reported that genus Tagetes comprises about 33 species and Bailey (1951 and 1976) mentioned over 30 species, however, Turner and Nesom (1993) reported that Tagetes is made up of nearly 55 species distributed in the American continent, most of them located in Mexico. The two species Tagetes erecta and Tagetes patula are commercially important. Details of these species are given below.

INTRODUCTION

Marigold is an important flower crop and constitute as one of the five most commonly cultivated and used flower in urban and rural India. They are extensively used for making garlands, beautification and other purposes i.e. pigment and oil extraction and thera eutic uses A art from these uses marigold is a widely grown plant in gardens and pots. It is highly suitable as a bedding plant, in a herbaceous border and is also ideal for newly planted shrubberies to provide colour and fill the space. French marigold is most ideal for rockery, edging, hanging baskets and window boxes. Flowers remain fresh for 4-5 days at room temperature and are used for religious offerings and social functions. Recently marigolds are grown commercially for extraction of carotene pigments mainly xanthophylls. The carotenoid extracted from petals are added to poultry feed for intensification of yellow colour of egg yolk. Lutein which is the major constituent of xanthophylls is used for colouring food stuffs. Purified extract of marigold petals containing lutein dipalmitate is marketed as an ophthalmologic agent under the name adaptinol. Dietary carotenoids can be used to treat cancer and photosensitivity diseases.

Marigold leaves contain a distinct odoriferous oil. Wild marigold (Tagetes minuta) oil has valuable and precious essential oil which is used in high grade perfumes and cosmetics. Ketones present in the oil are base material for synthesizing aroma chemicals. Marigold essential oil has bronchodilatory, tranquilizing, anit-inflammatory as well as insect repellent activities. The floral extract of marigold is used for treating eye diseases and ulcers.

Abstract: Among the annual flowers, marigold is commercially important loose flower crop in India. Marigold types with odourless foliage with orange to light lemon colour are available in world market. Being cross pollinating and seed propagated, progeny can segregate widely for traits due to heterozygosity. Improvements in marigold as cut flowers, larger flowers, more intense flower colour, an expanded flower colour range, more uniform plant habit, earlier flowering, more xanthophylls and extended bloom time are future breeding objectives. The use of intraand interspecific hybridization, heterosis, polyploidy and genetics of traits have been presented with a focus on creating novel transformations for this crop in future.

Introduction

Marigold is an important flower crop in India. They are extensively used for making garlands, beautification and other purposes i.e. oil extraction and therapeutic uses. Apart from these uses marigold is a widely grown plant in gardens and for pots. Marigolds are also grown commercially for extraction of carotene pigments mainly xanthophylls. The carotenoid extracted from petals are added to poultry feed for intensification of yellow colour of egg yolk. Lutein which is the major constituent of xanthophylls is used for colouring food stuffs.

Marigold plantation has been found beneficial to reduce the population of nematodes. Root-knot (Meloidogyne spp.) can be effectively managed in the field without pesticides.

Genetics

Marigold belongs to family Asteraceae. There are about 33 species of the genus Tagetes. Important species are T. erecta, T. patula, T. tenuifolia, T. lucida, T. lacera, T. lemmonii, T. minuta, T. pusilla and T. corymbosa. The chromosome number in diploid species i.e. T. erecta, T. tenuifolia, T. elongata, T. lemmonii, T. jaliscensis and T. lucida is 2n = 24, however, tetrapoid species i.e. T. patula, T. minuta, T. remotifolia, T. mendocina and T. biflora is 2n = 48.

Marigold (Tagetes spp.) is an important annual flower crop; native to Central and South America especially Mexico and belongs to family Asteraceae (Compositae). It is commonly known as “Gainda” in India and also called as “Friendship Flower” in United States of America. Loose flowers of marigold are in great demand throughout the year. It is commercially grown in tropical and subtropical regions of India owing to its ease in cultivation, hardy nature, wider adaptability and year round availability of single, semi-double and double flowers of vibrant colours. Marigold is grown over an area of about 66.09 thousand hectares with production of 603.18 thousand MT loose flowers in India. Major states involved in loose flower production of marigold are Karnataka, Madhya Pradesh, Gujarat, Andhra Pradesh, West Bengal, Maharashtra, Haryana and Chhattisgarh. In India, Assam is the only state, which produces marigold for both cut as well as loose flower purpose on an area of about 0.61 thousand hectare (Anonymous, 2016a).

Marigold is a cross-pollinated flower crop and it is pollinated by insects (Kaneko et al., 1990). It bears terminal and solitary inflorescence, known as head or capitulum, which possesses long and hollow peduncle with swollen apex and campanulate involucres (Setshogo, 2005). Capitulum consists of peripheral ray florets and central disc florets. Ray florets are pistillate, ligulate, sessile, epigynous and zygomorphic, whereas, disc florets are bisexual, tubular, sessile, epigynous and actinomorphic (Subrahmanyam, 1996 & Setshogo, 2005).

African marigold (Tagetes erecta L.) is a diploid species (2n = 2x = 24), while, French marigold (Tagetes patula L.) is a tetraploid species (2n = 4x = 48) with basic chromosome no. of x = 12 as revealed by breeding work of various researchers (Towner, 1961, Chen and Lin, 1981, Chen and Lin, 1982, Serrato-Cruz et al. 2000, Zhang et al., 2011). Tagetes erecta and Tagetes tenuifolia are diploid species, whereas, Tagetes patula, Tagetes minuta, Tagetes biflora and Tagetes remotiflora species are tetraploid in nature (De, 2017). On the basis of floral morphology; three different types of male sterile systems i.e. apetaloid, petaloid and gynomonoecious types was observed in African marigold (Prakash et al., 2016). Out of these, apetalous male sterility (femina type) is more reliable and preferred over petalous male sterility because later is more prone to break down (Goldsmith, 1968 & Janakiram, 2004). Apetaloid male sterility was controlled by single recessive gene (Prakash et al., 2016). A monogenic recessive male sterile apetalous mutant was detected from T. erecta population by Khoshoo (1979). Cyto-genetic male sterility is also found in marigold (De, 2017). Petaloid and gynomonoecious male sterile systems were controlled by cytoplasmic inheritance (Prakash et al., 2016). In marigold, cytoplasmic genetic male sterile lines were also developed for commercial production of F_l sterile hybrids (Pratibha et al., 2000).

Marigold is one of the dominant loose flower crops in India, particularly important for religious ceremonies, festivals, weddings, garlands and decoration. The principal cultivated types include African marigold (Tagetes erecta) and French marigold (Tagetes patula). The chapter discusses the origin, distribution, genetics, botanical characteristics and important varieties of marigold. It also highlights emerging applications such as lutein extraction, natural colourants, culinary uses and companion planting. Detailed production practices cover climate, soil, propagation, nursery management, land preparation, nutrient management, planting, irrigation, pinching and flower harvesting. Important pests and diseases, postharvest handling and yield are also discussed for efficient commercial production.

ABSTRACT

The Mumbai region of Maharashtra has been witnessing very rapid urbanization development in terms of industrial, commercial and residential establishments. This has resulted in reclamation of tidal flats and estuarine regions. The ‘marine clay', characteristic of this environment has high swelling potential and consequently affects the performance of the structures. This will have a serious negative impact on the urbanization expansion. In this study, an attempt is made to map the spatial distribution of these expansive clays using the state of art Hyperion data. Reflectance spectra of representative samples collected from the field is used to map marine clays using Spectral Angle Mapper (SAM) technique. Laboratory analyses of these foundation soils (reflectance spectroscopy, mineralogy and Atterberg limits) indicate that they have significant amount of montmorrilonite and has good swelling potential (A_C>1.4). The derived expansive clay abundance map will be of use while planning appropriate remedial measure and future development.

Key Words : Swelling clay, Spectral characters, Geotechnical properties

1. I Kilo joule - 10 joule.

2. 1 Mega joule -10º joule.

3. 1 Kilowatt hour-3.6*10 joule.

4. The heat engine converts heat energy into mechanical energy.

5. The machine which converts one forms of energy to another form is called as engine or prime mover.

6. Fahrenheit scale is called as British thermal unit and denoted by B.Th.U.

7. Internal combustion engines using coal gas as fuel was made by Frenchman Etienne Lenoir (1860).

8. Silent gas engine was developed by Germans Nileolansotto & Eugen Langen.

9. Rudolph diesel made the first diesel engine in 1894.

10. TDC is also called as inner dead centre.

The resources on the land have started showing sign of faster depletion owing to the population explosion, over exploitation of mineral and water resources and also the improper exploitation and the related wasting of the natural resources. Hence a time has come to search for more and more newer natural resources amongst which the ocean resources gain supreme importance as this treasure is yet to be hunted due to the non - availability of suitable technology for the same.

Such ocean resources mainly include the mineralogical and biological resources. The ocean biological resources, their birth, growth, population and migration greatly depend as chlorophyll content, total dissolved oxygen, total suspended solids, salinity etc. These parameters which constitute the marine environment drastically change in a quick span of time owing to the dynamically changing marine forces.

Abstract

GIS in marine fisheries has taken off much later than its application in land. But the strides made in this field since 1990’s has been quite significant, as many serious mapping studies and modeling initiatives have been recorded. With the third dimension added to the 2D spatial data, the marine GIS have all the ingredients of making it a fertile domain for research for decades to come. Most of the studies and products pertaining to GIS in fishery management had been revolving around mapping of habitats, geo-referencing of catch and effort data and modeling linking oceanographic and biogeochemical factors with living resources. Satellite remotely sensed information like ocean colour can act as a surrogate to fish biomass. Further remotely sensed SST, wind and other parameters can be effectively modeled to predict fish abundance, their habitat and related aspects. This manuscript pours into the various products and outputs based on GIS in marine fisheries around the world and the Indian initiatives.

Key words: GIS, marine resources, oceanography, primary productivity and climate change

1.0 Introduction

Geographic Information Systems (GIS) have been one of the most prolific scientific enhancements in recent past, which by virtue of out of box expansion of traditional database concept have opened up an entirely new vista of knowledge and opportunities. It’s probably one such unique application where information collation and analysis happen hand in hand resulting in palpable mining of data in perspective. A formal introduction to GIS would define it as a collection of computer hardware, software, data and personnel designed to collect, store, update, manipulate, analyze and display geographically referenced information. By virtue of its conceptualizations, there are no single GIS; systems can be assembled in an infinite number of ways. This is one such field, which probably always seeks the frontiers of innovations in the fields of ICT and modeling.

Abstract
Kerala with its extensive coastline and rich marine resources, plays a pivotal role in India’s fisheries sector. This paper delves into the multifaceted dimensions of marine fisheries in Kerala, highlighting its economic, environmental, and social significance. Kerala boasts an exclusive economic zone (EEZ) spanning 2.19 lakh sq km and a coastline spanning 590 km. Its marine waters, especially in the Arabian Sea, are highly productive. The paper explores the recent advancements and achievements in Kerala’s fisheries sector, driven by mechanization and motorization initiatives. In 2022, Kerala recorded its highest marine fish catch of the decade, totalling 6.87 lakh tonnes, marking a 24% increase from the previous year. Key species such as oil sardine and Indian mackerel demonstrated significant recoveries, underscoring the sector’s resilience and adaptive capacity.
Sector-wise analysis reveals that pelagic finfishes dominate the landings, with oil sardine and Indian mackerel leading the pack. Demersal and crustacean landings also contribute significantly to the state’s fishery output. The abstract discusses the distribution of catch among different districts, with Ernakulam emerging as a major contributor. Furthermore, the socio-economic impact of marine fisheries is examined, highlighting its role in livelihoods for approximately 8 lakh people across 222 fishing villages. The sector not only provides income but also supports cultural identities and community cohesion along Kerala’s coastal areas.
Keywords: Marine resources, Production, Kerala, Landing and Fisheries sector.

ABSTRACT

The world ocean with a coastline of approximately 3,50,000 km is the largest ecosystem on earth. Marine organisms are the major, sustaining components of ecosystem processes and are responsible for biogeochemical reactions that drive our climate changes. Despite this, many marine organisms are poorly described and little is known of broad spatial and temporal scale trends in their abundance and distribution. With new molecular and analytical techniques we can advance our knowledge of marine biodiversity at the species level to understand how marine biodiversity supports ecosystem structure, dynamics and resilience. We can then interpret environmental, ecological and evolutionary processes controlling and structuring marine ecosystem biodiversity. In biotechnology applications marine microbes represent a potential source for numerous commercially important biomolecules and their bioremediation capabilities are also remarkable. They also play a crucial role in decomposition of organic matter and cycling of nutrients. Microbes also serve as food for some bottom-living organisms. Understanding and preserving biodiversity was one of the most important global challenges for the past 20 years and will continue to be an important scientific issue into the new millennium. Our knowledge of marine microbial diversity has, however, been severely limited by relying on microorganisms that have been cultured which are less than 1%.

Introduction
Marine Pollution
The pollution of the sea substances that humans have directly or indirectly introducedinto the marine environment, which can have negative impacts on the ecosystem, including health risks to people, obstructions to marine activities, and a decline in the quality of seawater.
It happens when invading species or chemicals or particles or garbage from industry, agriculture, or residential sources find their way into the ocean and can have detrimental impacts.
The majority of maritime pollution originates on land. Nonpoint causes of pollution include wind-blown debris and agricultural runoff.
A great deal of potentially harmful substances stick to small particles, which plankton and benthos animals (most of which are deposit or filter feeders) then consume.
Pesticides swiftly find their way into marine food webs after entering the marine ecology. These pesticides can induce diseases and mutations once they enter food webs, which can be dangerous for both humans and the entire food chain.
Marine food webs may also be exposed to toxic metals. These have the power to alter biochemistry, behavior, reproduction, tissue composition, and growth inhibition in marine organisms. Additionally, a lot of animal diets contain a lot of fish meal or fish hydrolysate. Toxins from the sea can thus spread to land animals and then show up in meat and dairy products.

Increasing pressures exerted on the environment by humans make protection of natural areas crucial for the preservation of biological diversity. Protected areas are one of the most effective tools available for conservation of biodiversity.

The IUCN defines a Protected Area as ‘an area of land and/or sea specially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultured resources, and managed through legal or other effective means.

Since 1986, the IUCN commission on National Parks and Protected Areas (CNPPA) has been promoting the establishment and management of a global representative system of Marine Protected Areas (MPAs) which play a critical role in the conservation of biodiversity. MPAs are growing in importance globally as practical and potentially effective options for the management of fisheries, the protection of biodiversity and the generation of income from eco-tourism. The effective management of MPAs to ensure that they meet their declared objectives poses many challenges.

The IUCN has defined an Marine Protected Area (MPA) as ‘Any area of the intertidal or subtidal terrain, together with its overlying water and associated flora, fauna, historical and cultural features, which has been reserved by law or other effective means to protect part or all the enclosed environment (Kelleher,1999).

Abstract
The oceans, which make up more than 70% of Earth’s surface, are home to a vast variety of marine ecosystem services that sustain human civilization, health, and the economy. The 8.06% percent of the ocean covered by marine protected areas with an around of 18,200 marine protected areas with a total area about 29,202,667km2. A novel, pertinent, and science-driven framework for classifying regions and connecting their effects on people and the environment is the marine protected area system. Marine protected areas create high-quality metrics to augment the official World database on protected areas reporting by utilizing science-based frameworks to evaluate the degree of protection and stage of setup throughout the world. This article presents the most recent official coverage statistics for marine protected areas.
Keywords: Marine Protected areas, Ecosystem, Protection and International
Distribution of Marine Protected Areas
There are 8.06% marine protected areas (MPAs) in the world. The Global Ocean can be divided into areas within national jurisdiction (National Waters) and those in international waters (Areas Beyond National Jurisdiction (ABNJ)). Governments in national waters with established legislative frameworks find it easier to establish MPAs. MPA creation is more challenging in ABNJ because of the intricate legislative system that governs the state.
As a result, compared to ABNJ, a significantly larger number of MPAs have been established within national waters. 39% of the world’s ocean is made up of national waters, of which 18.43% are currently protected areas.

Introduction

The traditional approach to transferring genes from wild to cultivated species is based on interspecific hybridization followed by selection of hybrids that combine the trait with the cultivated genetic background. This breeding strategy is achieved by various backcross generations in which the selected hybrids at each generation are crossed back to the cultivated genotype with the aim of reducing the wild genome and its undesirable traits. The use of molecular markers has allowed this breeding approach to be greatly improved, since these markers directly reveal genetic variability through DNA analysis (Staub et al. 1996), and therefore their detection is not influenced by environmental effects. Since the development of numerous molecular markers for plant genometatic analysis, the possibility to select the genotype instead of the phenotype has been closely examined, leading to the concept of molecular marker-assisted selection (MAS; Paterson et al. 1991). The basic concept of MAS for crop improvement has been well discussed by Collard et al. (2005) which is most appropriate for this chapter. The most widely used markers suitable for MAS are RFLP, RAPD, AFLP, and SSR. Their common origin is point mutation or chromosome rearrangements that were accumulated during the evolution of the species without negatively influencing their survival and reproduction. The choice of the most suitable markers for MAS can differ and depends on the labor required for their detection, possibility of revealing single or multiple loci, dominant or co dominant nature and costs.

Marker Assisted Selection (MAS)

Marker Assisted Selection [MAS] is defining as the indirect selection for a desired plant phenotype based on the banding pattern of linked molecular (DNA) markers. It is based to infer the presence of a gene from the presence of a marker which is tightly linked to the gene of interest and high heritability of the gene of interest. Marker assisted selection (MAS) is also known by other names as marker aided selection and marker assisted breeding (MAB).

25.1 Introduction

The method of selection in which a gene/QTL (Quantitative Trait Locus) is selected on the basis of the genotype of the molecular marker (also called DNA marker) linked to this gene/QTL is known as marker-assisted selection (also called marker-aided selection). The idea of marker-assisted selection (MAS) was first advocated by Tanksley (1983). MAS can be used in combination with the conventional breeding methods or novel breeding schemes could be devised to take full advantage of the marker data. MAS has been widely used for introgression of the desired genes and QTLs using backcross programmes.

25.2 Marker-Assisted Backcrossing (MABC)

The backcross programme based on molecular marker is usually called marker-assisted backcrossing (MABC). MABC has three activities: (a) foreground selection, (b) background selection and (c) recombinant selection.

25.2.1 Foreground Selection

The use of molecular marker to select the gene/QTL being introgressed is known as foreground selection. The objective of foreground selection is to select the target gene, i.e., the gene being introgressed, without phenotypic evaluation for the trait governed by the target gene. Foreground selection for a gene/QTL will be highly desirable in a variety of situation, some of which are listed below:

ABSTRACT

In last twenty years, molecular biology has revolutionized conventional plant breeding techniques in many areas. The use of molecular markers in conventional breeding techniques has also improved the accuracy of selection and allowed breeders to produce varieties with combined traits that were difficult before the advent of DNA technology. Among vegetables, onion (Allium cepa L.) is the most important cash crop of India. Onion productivity in India is much lower (11.38 tones / ha.) compared to other countries (44.1 tones / ha. in Japan). Purple blotch disease (PBD) caused by Alternaria porri (Ellis) Ciferri decreases the yields by up to 50 percent. Genetically resistant onion varieties are the most economical, simple and eco-friendly mode of disease management. The advent of mo- lecular markers provided the opportunity to understand the genetic resistance more pre- cisely. In this paper we present our successful efforts in developing PCR based markers linked to purple blotch disease resistance, so that such markers can be easily integrated into PBD resistance breeding program in onion. Onion germplasm was screened for PBD resistance. Line PBR 287 was identified as a good source of resistance and the genetics of inheritance of resistance in this line was worked out. The protocols for isolating good quality DNA and PCR amplification conditions were standardized. 37 polymorphic mark- ers were identified between resistant and susceptible parents. Crosses were made between resistant and susceptible parents. Parents, F₂ and individual F₂ progenies were subjected for analysis of genetics of resistance and RAPD marker analysis. F₂ individuals segregated in 3:1 ratio for resistance. DNA from resistant and susceptible F₂ individuals was pooled separately for Bulked Segregant Analysis (BSA). BSA identified one RAPD marker of 900bp being linked to resistance. Further Chi-square test for detecting the deviation of segregation of this 900bp marker confirmed segregation with classical Mendalian ratio 3:1 for a monogenic trait. Identified marker is of great practical utility to the plant breeders to screen large number of populations for purple blotch disease resistance at the early stages of the crop even in absence of the pathogen.

ABSTRACT

During the efficient genetic transformation of plants with the gene of interest, some selectable marker genes are also used in order to identify the transgenic plant cells or tissues. Antibiotic and herbicide selective agents and their resistance gene are commonly used to introduce economically valuable genes into crop plants. According to the biosafety authority and consumer view points, the presence of selectable marker genes in released transgenic crops may be transferred to weeds or pathogenic microorganism in the gastrointestinal tract or soil, and will make them resistant to treatment with herbicides or antibiotics, respectively. Sexual crossing also raises the problem of transgene expression because redundancy of transgenes in the genome may trigger homology-dependent gene silencing. The future potential of transgenic technologies for crop improvement depends greatly on our abilities to engineer stable expression of multiple transgenic traits in a predictable fashion and to prevent the transfer of undesirable transgenic material to non-transgenic crops and related species. Therefore the development of efficient marker free transgenic plants system is very essential. That is why many technologies and various approaches designed to timely elimination of transgenes when their function is no longer needed. Due to the limited number of available selectable marker genes, in future the stacking of transgenes will be increasingly desirable. The production of marker-free transgenic plants is now a critical requisite for their commercial deployment and also for engineering multiple and complex trait. Here we describe the current technologies to eliminate the selectable marker genes (SMG) in order to develop marker-free transgenic plants and also discuss the regulation and biosafety concern of genetically modified (GM) crops.