eChapters

The cattle skeleton, like that of other mammals, is a complex structure that provides support, protection, and mobility. The skeleton for study purposes is divided into two main parts: the axial skeleton and the appendicular skeleton. The axial skeleton forms the central axis of the body and includes bones such as the skull, vertebral column, ribs, and sternum. The appendicular skeleton comprises the bones of the forelimb (scapula, humerus, radius-ulna, carpals, metacarpals and phalanges) and hindlimb (os coxae, femur, patella, tibia-fibula, tarsals, metatarsals and phalanges).

• The axial skeleton is comprised of several key structures that form the central core of the animal skeleton.

• This includes the bones of the skull, which encase and protect the brain, the vertebral column or spine, which provides support and houses the spinal cord, as well as the ribs and the sternum, which together form the rib cage, protecting vital organs such as the heart and lungs.

• These components work together to provide structural support and protection for the body’s central organs.

Skull Bones

The skull is a complex structure that varies greatly across different animal species, reflecting their unique evolutionary adaptations, dietary habits, and ecological niches.

Generally, the skull serves several critical functions: protecting the brain, supporting facial structures, and providing attachment points for muscles involved in feeding and expression.

While fertilizer injectors that mixes fertilizer solutions with the irrigation water flow in the micro irrigation systems, a scientifically prepared fertigation schedule is the software that farmers need to implement a successful fertigation plan.

Though water soluble fertilizers are a special grade of fertilizers manufactured for fertigation per se; I have been assisting farmers to do fertigation with conventional fertilizers, those are familiar to them; like Urea for N, white muriate of potash (MOP) for K. Only in the case of P source they need to acquire water soluble special fertilizers like Monoammonium Phosphate (MAP) or Phosphoric acid. Historically, fertigation by our small holder farmer began in India just by fertigating Urea alone. And applying P and K as direct dry application to the soil with Single Super Phosphate (SSP) or pink MOP, both are not water soluble. Gradually, when farmers realised that fertigation is giving them more yield of the crop and income they warmed up to the idea of full fertigation and demand for water soluble fertilizers like MAP, White Potash, SOP etc. grew.

A. CEREALS

1. Rice (Oryza sativa)

RD 60:20:20 kg/acre NPK

(Recommended by TNAU)

 

Horticultural crops include the fruit crops, vegetables, spices, plantation crops, medicinal plants, aromatic plants, commercial flower crops and ornamental plants.

Knowledge on the methods by which these reproduce is of primary importance from the standpoint of plant breeding. Besides, their annual or perennial nature also decides the methods of breeding to be adopted to get desired improvement.

Two divisions of methods of reproduction commonly recognized are:

1. Asexual i.e. vegetative parts of the plants are utilized to produce new individuals.

2. Sexual i.e. gametic fusion, the resultant zygote develops into seed which is utilized to produce new individual.

This group can be further placed in several sub divisions according to the mode of pollination. They are

a. Naturally self pollinated crop - (e.g. tomato, pepper, brinjal) wherein cross pollination occurs less than 4 % only.

b. Often cross pollinated crop- (e.g. chillies, bhendi) wherein though self pollination is more frequent, cross- pollination may occur so frequently that some methods of preventing cross pollination between varieties and strains of different genotypic constitution must be followed throughout the breeding programme.
Common breeding methods can be applied to the above two groups, however, the parents chosen for breeding under often cross pollinated crop need to be selfed for few generations to select desirable, homozygous lines.

TROPICAL AND SUBTROPICAL FRUITS

2.1 Mango
 

Mango is considered to be an allopolyploid. The chromosome number is 2n =40. The polyembryonic seedlings of cv. Vellaikolumban, earlier reported to be 2n= 80 was later shown to be a diploid. In Canary Island, a putative tetraploid viz Gomera-1 has been identified.

Floral biology

Flower starts opening early in the morning from 4-7 a.m. and maximum flowers open between 9.30-10.30 a.m. and complete 11 a.m. Dehiscence of anthers takes place at 11.30 a.m. and it continues up to 3.45 p.m. The pollen grains are oval, or triangular or oblong. Stigma becomes receptive even 18 hours before flower opening. Mode of pollination is entomophily; nectar is present to attract the insects.

The flowering duration is usually of short i.e. 2 to 3 weeks. The mango inflorescence or panicle bears mainly two types of flowers - male and perfect. The number of flowers per panicle varies between 1000 to 6000 depending upon the variety and climatic factors. The percentage of perfect flowers varies between 0.74 per cent in Rumani, 16.41 to 55.7 per cent in Neelum and up to 69.8 per cent in Langra.

3.1 Tomato

Tomato (Lycopersicon esculentum) is an important vegetable crop. Its 2n= 24.

Floral biology

Flowers are borne in small forked racemose cyme. Anthesis starts at 6.30 a.m. and continues up to 11.00 a.m. Anther dehiscence is longitudinal. It occurs 1-2 days after opening of corolla. The stamen sheds its pollen when the style grows up through anther tube, thus self-pollination occurs. When the stigma protrudes above the anther tube, chances of cross pollination through bees increases. The optimum temperature for pollination is around 21°C.

A ‘spice’ is a seed, fruit, root, bark, bulb, corm, rhizome or any other part of a plant primarily used for enhancing the taste, flavor or color of food. Some spices serve as preservative of food substances. Many spices have antimicrobial properties. Spices are sometimes used in medicines, religious rituals, cosmetics, perfumes etc. Spices are more commonly used in countries having warmer climates, especially in meat preparations. Many spices have substantial antioxidant property due to the presence of phenol compounds, particularly flavanoids.

India is the major producer of spices and contributes about 75 per cent of world’s spice production. Developing and under developed countries of the world supply about 55 per cent of spices to the global markets and the major markets in global spice trade are the United States of America, The European Union, Japan, Singapore, Saudi Arabia and Malaysia.

1. Ginger (Zingiber officinale)

‘Ginger’, which originated in Southeast Asia has a long history that goes back over 5000 years when the Indians and Ancient Chinese considered it as a tonic root for all ailments. At an early date it was exported to Ancient Rome from India and was used extensively by the Romans. Subsequently it was cultivated in several other countries for its medicinal value. Ginger is cultivated in most of the states of India. Kerala and Meghalaya are the major ginger growing states. India’s production of ginger constitutes about 50 per cent of the total world’s production.

Ginger is an erect, herbaceous , perennial, flowering plant, the rhizome of which is used as a spice. Ginger is an ancient spice and is a common ingredient in many Asian foods and is used in soups, curries, noodles, stews etc. It is widely used to flavor beverages, such as tea, coffee, lemonades, cocktails etc. In many places across the world ginger is used in sweets, alcoholic beverages, such as ginger beer and wine. Ginger has powerful anti-inflammatory properties. Further it has many other health related benefits, such as ability to help with arthritis, osteoarthritis, relieves nausea and pain, prevents cancer, improves respiratory conditions and reduces flatulence. It also boosts bone health, strengthens the immune system and increases appetite.

1. Genus - Pythium (Type species - Pythium aphanidermatum)

‘Pythium’ is a large genus comprising of more than 200 species. Species of Pythium are either terrestrial or aquatic. They are found world wide and most of them are plant pathogens on many economically important cultivated crops, as well as wild plants. They are facultative saprophytes and can live saprophytically in the soil and plant debris for indefinite periods in the absence of suitable hosts. Pre-emergence and post-emergence damping off of seedlings of numerous angiospermic plants, root rot, rhizome rot and fruit rot are the most common diseases caused by species of Pythium.

Pythium debaryanum, Pythium aphanidermatum, Pythium myriotylum, Pythium indicum, Pythium vexans and Pythium graminicolum are some of the most important plant pathogens, that cause damping off, seed decay, soft rots and root rots of many economically important crops, such as chillies, eggplant, tobacco, tomato, castor, potato, ginger etc.

Life cycle of Pythium

The mycelium of the fungi consists of slender, hyaline, coenocytic hyphae. The hyphae grow both inter- and intra-cellularly. No haustoria are produced.

The active management of soil nutrients to ensure optimal plant nutrition has been a fundamental practice in agriculture since its inception. For centuries, production of agriculture depended on the organic materials recycling like manure and crop residues. Interest in plant nutrition dates back to ancient times, first captivating philosophers and later becoming a subject of rigorous scientific inquiry. The history of how plants obtain nutrients is marked by numerous misconceptions and incorrect theories. Exploring the long-standing efforts to uncover this essential agricultural process highlights the perseverance and brilliance of early thinkers and scientists. It also underscores that modern understanding, which may now seem straightforward, is the culmination of significant scientific endeavour. The concept of managing fertility of soil to boost yield of crops is far from new—its origins are intertwined with the earliest practices of agriculture. Ancient civilizations recognized the value of applying organic matter such as green manure, farmyard manure, night soil, bone, and wood ashes to enhance soil productivity.

Introduction

A total of 109 elements have been discovered and incorporated into the periodic table. Many of these elements are found in the earth’s mantle, crust, and soil, though their abundance varies. The chemical makeup of plants is, to some degree, influenced by the composition of the soil. However, since plants are active organisms, they exhibit selectivity in absorbing elements from the soil. Plants accumulate elements at different rates, absorbing some in large quantities, others in smaller amounts, and excluding most altogether. Before proceeding, it is important to familiarise with several key terms frequently used in this chapter.

Nutrient: A nutrient element is essential for an organism to complete its life cycle, and a deficiency in this element leads to specific deficiency symptoms. The negative effects can only be corrected by providing that particular element. Nutrient elements essential for plants may not be necessary for other organisms, and vice versa. Depending on availability, the nutrient levels in a plant can be deficient, sufficient, or toxic. A nutrient is considered deficient when its concentration is so low that it significantly limits growth and causes recognisable deficiency symptoms. If nutrient levels cause reduced growth without visible deficiency symptoms, they are termed insufficient. The nutrient content range in plants that supports optimal yield of crops is considered sufficient. When the concentration of a nutrient becomes high enough to significantly reduce growth, it is considered toxic.

1.1 Introduction

‘Cucurbits’ is a term coined by Liberty Hyde Bailey for cultivated species of the family Cucurbitacae. During this current century the term has been used not only for cultivated forms, but also for any species of the family Cucurbitacae. Cucurbits are frost sensitive, predominantly tendril-bearing vines which are found in subtropical regions around the globe. A few numbers of species those are native to or cultivated in temperate climate are prolific seed producing annuals or perennials that live for one season until killed by frost (Robinson and Decker-Walters 2004). Other vernaculars applied to the family Cucurbitacae and several of its members are ‘gourd’, ‘melon’, ‘cucumber’, ‘squash’ and ‘pumpkin’.

2.1 Insect Pests

Insects are often a major obstacle to the successful production of cucurbits (York, 1992). They can severely reduce yield, injure or kill plants, spread diseases and adversely affect fruit quality. A number of insect pests, mites and nematodes have been found to infest cucurbitaceous vegetables but fortunately, in India, fruit flies and a few species of beetles are of economic importance; aphids and blister beetles though of regular occurrence, seldom cause severe damage.
 
Other insect pests reported to infest the cucurbitaceous vegetables are pumpkin caterpillar, Diaphania indica (Sounders), snake gourd semilooper, Plusia peponis Fab., white fly, Bemisia tabaci Genn., stink bugs, Apspongopus spp. and flea beetle, Phyllotreta spp. etc. These biotic pressures on the crops are increasing day by day due to round-the-year intensive cultivation of photo and thermo insensitive cultivars as well as indiscriminate use of toxic agro-chemicals in the present era of chemicalized agriculture.

Tremendous genetic diversity occur within different crops of this family with respect to their adaptability. Some cucurbits are grown in tropical, subtropical or arid deserts whereas other prefer to grow in temperate conditions. Harvested fruits and vegetables can be potentially exposed to numerous abiotic stresses during production, handling, storage and distribution (Hodges, 2003). However, when the abiotic stress is moderate or severe, quality losses almost always are incurred at market (Toivonen, 2003). Annually about 42% of the crop productivity is lost owing to various abiotic stress factors (Oerke et al., 1994). One of the key factors for abiotic stress in crop plants is the ill effect of global warming which may cause reduced precipitation, less snow pack, and earlier snow melt, leading to drought conditions. In addition about 20% of the world’s irrigated lands are affected by salinity (Zhu, 2001), a situation worsened by climate changes.

India has a very wealthy tradition of herbal medicines for the treatment of many health discomforts.The tradional healing practicese are common and popular among all the tribes and communities.It is evident that many communities have so much belief in their ethnobotanical knowledge that they often prefer a traditional medicineal practicener over any certified medical personality. Among all the plant species which have been already reported by many researchers for their ethno medicinal properties are getting very rare in their original habitat.These plants are obviously of great medicinal importance and immediate need of conservation.Some medicinal plants which are exclusively found in forest are getting lost due to habitat fragmentation and enormous deforestation.

The publication of “Flora of British India” by Hooker (1872-1897) was followed by a series of regional floras by Cooke (1901-08) for Bombay presidency; Prawn (1903) for Bengal: Duthie (completed by Parker & Turrill, 1905-29) for upper gangetic plains and adjacent Siwalik and of sub Himalayan tracts; Kanjilal (1966) for the forest flora of Uttar Pradesh; Gamble (completed by Fisher, 1915-1936) for Presidency of Madras; Haines (1921-1925) for Bihar and Orissa: and Kanji et al (1934-1940) for Assam. Duthie’s work was completed by Raizada and associates (Raizada, 1954, Raizada et al. 1961; 1983; Raizada & Jain, 1964, 1966). Later, Raizada (1976) brought together all additions made to Duthie Flora. However, the trends of additions has persisted afterwards and is hoped to continue onwards as well. Revision of old floras has become all the more important because the nomenclature of a large number of species has changed in accordance with International Code of Botanical Nomenclature (1956, 1961, 1966, 1972, 1978 & 1983).

Collection trips were organized in a planned manner so as to cover every locality in all three seasons. Rural and remote areas which were thus far practically unexplored were surveyed more intensively. Frequency of collection trips was twice a week during first year; once a fortnight in third and once a month in the last and forth years. During the field work, observations on the habit and habitat; flower colour; fragrance; fruiting, colour of the bark and blaze in case of trees and shrubs; dominance and sociability of the collected plants were entered into rough field book. In the mean time information regarding medicinal or other uses, if any, were gathered from local inhabitants, vaidyas and haquims. Plants of small size were uprooted carefully and pressed as such. In case of larger plants, care was taken so that specimens should have flowers, fruits, leaves and stems of young and old stages. At least four specimens, for making herbarium sheets, were pressed at spot after tagging; and a tagged bundle of a few plants was taken in a polythene bag for study in laboratory.

Dicotyledons
Ranunculaceae
Juss., Gen. 231. 1789. Type: Ranunculus L.
Ranunculus L., Sp. Pl. 548. 1753. Lectotype: R. auricomus L.
R. sceleratus ssp. sceleratus; Tutin in Fl. Eur. 1: 233. 1964. Ranunculus sceleratus L., Sp. Pl. 551. 1753; Fl. Alld. 1: 2.
Vernacular Name: Jaidhania., Kandira
Description: Annual herbs, erect up to 60-70cm tall. Stem, fistuler simple, glabrescent below, branched and pubescent Leaves 3-5-palmately lobed o partite, lower long-petioled, higher ones panicled. Flowers yellow, Sepals reflexed. Petals oblong. Stamens and carpels numerous. panicled. Achenes with an intramarginal rib. Receptacle pilose.
Distribution: North temperate.
Habitat: A Common-herb during winter near river and pond banks: in wet places in gardens.
 

A. General
        
B. Leaves and Floral Terminologies
        
C. Diversity in the Flower
        
D. Diversity in Fruits
        
E. Terminologies Related to Seed

Accent : It is created in the garden to avoid the monotonous view. Mostly unusual objects like tall fountain, tree, statue etc are used to create the effect.

Acre: A unit of measurement of land area equivalent to 4000 sq.met or 0.4047 hectare.

Acrylic: It is a glassy thermoplastic that is incorporated in rigid plastic to enhance wither ability.

Aging: Refers to the processes acquiring maturity with the passage of time or normally an increment of time, which may or may not be accompanied by physiological changes including senescence. Aging thus includes a much ‘wider span’ of physiological processes, which may either “weaken the organism or to be neutral”.

Agmark: It is Agriculture Produce, Grading & Marketing Act, 1937 & voluntary in nature.

Anaerobic respiration: An incomplete oxidation of food to release partial energy takes place in the absence of atmospheric oxygen and occurs in cytoplasm.

Analytical chemistry: Deals with detection and estimation of elements and compounds.

A. General
        
B. Bulbous Plants
        
C. Greenhouse Technology
        
D. Plant Breeding
        
E. Plant Physiology
        
F. Plant Tissue Culture and Biotechnology
        
G. Post Harvest Technology

A. General
        
B. Turf Grass
        
C. Indoor Plants

Manychemicalreactions innature,particularlyinlivingsystems,occur inaqueous solutions. Reactions are often carried out in the laboratory in aqueoussolution becausethese aregenerallymore rapid in solutionthanwhen puresolid reactions are mixed. Analysisof substancesmaybe qualitative or quantitative in nature. A quantitative analysisis one inwhich the amountor concentrationof a particular species in a sample is determined accurately and precisely.

1.1 Volumetric Analysis

Volumetric analysis is a quantitative analysis. It involves the measurement of the volume of a known solution required to bring about the completion of the reaction witha measuredvolume of the unknown solution.

The reaction used in volumetric analysis must fulfil the followingconditions;

Advances in analyticalchemistry and instrumentalanalytical chemistry in the pastfew decades have significantlyimproved, makingelemental determinations in soil extracts and water samples easier, faster and less challenging for the analyst. For most of the elemental analysis procedures, the more traditional wet chemistryprocedures havebeenreplaced byvarious analytical instrumental procedures that employ either emission or absorption spectrophotometry. The elemental concentration in prepared soil extracts and water samples can be determined by a number of instrumentalanalyticalprocedures.

The trend today is toward greater analytical sophistication, to multielement computer controlled analytical instrumentation, resulting in a less ended understandingof the analytical principlesinvolved, and “black box” concepts of instrument calibration, maintenance, and operation. Preparation of the analyte and suitable adaptation for a method of analysis requires an understanding, by the analyst, of the principle of the method as well as its requirements and limitations. Adequate testing is usually required before putting the method to use, following procedures such as those that have been adapted by the Association of Official Analytical Chemists (AOAC).

It is not possible to cover in adequatedetail every method of analysissuitedfor the elemental concentration determination in soil extracts and water samples. Therefore, the objective here is to provide sufficient background information about the instrumentalprinciples to guide the reader.

3.1 Concepts of Soil Sampling

Samplinginvolvesthe selection fromthe total populationof a subset ofindividuals upon which measurements will be made. The measurements made on this subset (or sample) will then be used to estimate the properties (or parameters) of the total population.Samplingisinherent toanyfield research programinsoilscience because the measurement of the total population is impossible for any realistic study.

Samplingdesign involves theselection of the mostefficient method forchoosing the samples thatwill be used to estimatethe properties of the population. The definition of the population to be sampled is central to the initial formulation of the research study. The sampling design defines how specificelementswill be selected from the population, and these sampled elements form the sample population.

Pedogenetic and soilgeomorphic studies focus on determining the processes thatformed the soilproperties or landscapes under study and the environments that controlled the rates of these processes. Pedonscale studies are closely associated with thedevelopmentof soil taxonomic systems andfocus onvertical, intrapedon processes. Soil geomorphic studies are the interface between quaternary geologyand soil science and soil geomorphologistsfocus on lateral transferprocesses and the historical landscape evolution. Hence sampling is difficult for a particular population and is differentfor differentstudy.

The influence of water quality on the soil and plant growth is related to the chemical and physicalproperties of the soil, the salt tolerance of the crop, the climaticregime of the area and the method,frequencyand the amount of irrigation water applied. Irrigation water quality refers to its suitability and sustainability for use in agricultural crops. The problems thatresultfrom the use of a particular irrigation water, vary both in kind and degree, and are modified by soil, climate and crop as well as by the skill and knowledge of the water user. As a result there is no set limiton water quality, rather itssuitability for use is determined by the conditions of use which affects the accumulation of water constituents andwhichmayrestrictcrop yield.The soilproblems mostcommonlyencountered and used as a basisto evaluate water quality are those related to salinity, water infiltrationrate,toxicityanda group of other miscellaneous problems. Numerous guidelines are available for evaluation of water quality. Time to time some of theseguidelines has been updated with modification of some criteria like SAR to Adj. SAR and the Adj. R_Na and development of new concepts like water qualityIndex (WQI) whichhave increasedour predictability. Thenewguidelines are relied heavily on old ones.The modified guideline by Ayers and Westcot (1985) was foundto be themost reliabletopredict thewaterqualityforirrigation.

Irrigated agriculture is playing a major role in enhancing food and livelihood security of a country. Supply of fresh water which is an importantinput for the sustainable and economic development of agriculture are not enough to meet the requirement of all sectors of economy. Reduced water availability to agriculture from the present share of 85% of country’s water resources to about 70-75% by 2020AD wouldaffect the capacity of the country to meet the food production target, unless supplies are augmented from unconventional sources. For future agriculture there are no alternatives but to rely on non conventional sources for partial alleviation of the forecasted water scarcity. Amongthese sources extraction of marginal quality groundwater and the waste water generatedfromurban and industrial activities have thepotential to augment the water supplies. Many associatedsoil, plant and environmental problems come up when these sources of water are directly used for irrigation. For addressing theseproblems and to get more benefit from thesesourcesof water, the first step is to understand how an irrigation water source affects the soil plantsystem.Thereforeknowledge of irrigationwaterqualityiscriticaltodevelop appropriate site and crop specific comprehensive short term and long term management programs.

CEREALS

Rice (Oryza sativa)

1. Rice blast
Pyricularia oryzae

‘Rice blast’ occurs in more than 80 countries across the world. The disease is more prevalent in Thailand, Japan, America, Guyana, Philippines and India. It is particularly serious in places, where rice is irrigated or receives heavy rainfall and where high levels of nitrogenous fertilizers are applied. Rice blast was first reported in China in 1637, in Japan in 1704 and in India in 1913. In India, it is found in all rice growing states, particularly in Telungu Desam, Karnataka, Maharashtra, Uttar Pradesh. Assam, Tripura, West Bengal, Bihar, Orissa, Himachal Pradesh, Punjab, Madhya Pradesh, Gujarat, Kerala, Tamil Nadu and Pondicherry and causes considerable damage to rice crop. In Tamil Nadu, the disease occurs in all rice growing districts and attains epidemic proportions in some seasons. Several rice blast epidemics have occurred in different parts of the world, causing yield losses ranging from 50 to 90 %. In Tamil Nadu, a serious epidemic of the disease occurred in 1919 in the Thanjavur Delta.

Symptoms. The disease, though chiefly a foliage disease, attacks other parts of rice plants, such as leaf sheath, rachis, joints of the culms and even the glumes. On the leaves, the initial symptoms appear as small bluish or grayish specks, which remain circular in older leaves. On young leaves, they enlarge and become eye-shaped, diamond-shaped or spindle-shaped spots, extending over several centimeters in length and about 1.0 cm. in width. The central portion of the lesion appears pale green or grayish green and water-soaked in the beginning. In older spots, the center becomes white to gray with a dark-brown margin surrounded by a yellow hallow. The lesions may coalesce, cover large area of the leaves and eventually the entire leaves are killed. The shape, size and color of the spots vary depending upon the variety, growth stage of the plants and environmental conditions. Similar spots may be formed on the leaf sheath also. During severe incidence, large areas of the leaves dry and die and the entire crop presents a burnt appearance. Hence the disease is known as ‘blast disease’. Leaf blast is more severe during the seedling and maximum tillering stages. In the nursery, the seedlings show numerous spots on the leaves, which wither and die. In case of severe infection, large number of seedlings may die. Blast also affects the leaf collar, which results in the death of the entire leaf.

The disease attacks the stem-nodes at the heading stage leading to production of ‘white panicles’ or the stem may break at the infected node. Rarely the internodes are affected. Further, at heading the fungus also attacks the panicle neck, which is girdled and becomes shining black and shrivelled. This is the most destructive phase of the disease and is known as ‘neck blast’, ‘neck rot’ or ‘panicle blast’. If infection of the panicle neck occurs early, the grains become chaffy and the panicle remains erect. If panicle neck infection occurs late, the grains become partially filled and because of the weight of the grains, the panicle breaks at the neck- node and droops. Sometimes, only parts of the panicle and joints of the culms and some glumes are infected and develop brown to black spots (Fig. 1).

Under conditions highly favorable for the pathogen, even the varieties resistant to the fungus under normal conditions are also attacked and small, round or short elliptical spots develop. However, the spots normally do not enlarge as typical blast spots.

FRUIT CROPS

Banana (Musa species)

1. Panama disease of banana
Fusarium oxysporum f.sp. cubense

‘Panama disease’, ‘Fusarium wilt’ or ’vascular wilt’ of banana is one of the most serious and destructive diseases of the crop. The disease was first reported from Australia in 1874. Now, it is widely distributed all over the world, including America, Africa, Sri Lanka, Burma, Thailand, Malaysia, Indonesia, Hawai, Fiji, the Philippines, India, Australia and New Zealand. In India, it is prevalent in the states of Assam, Bihar, Karnataka, Kerala, Tamil Nadu, Telungu Desam, Maharashtra and West Bengal.

Symptoms. Usually the symptoms are manifested, when the banana plants are about 5 months old. However, under highly favorable conditions for the pathogen, even 2 - 3 months old plants show wilt symptoms. Initial visible symptoms appear as pale yellow streaks, lengthwise in the petioles of the oldest, lowermost leaves. Two types of symptoms follow this. In the first type, the old leaves turn yellow progressively and finally they break from the petiole and hang down. In the second type, the leaves break from the petiole and hang down, without becoming chlorotic. Gradually, all the leaves collapse and hang down, except the crown, which alone stands upright. The newly formed leaves show yellow blotches and wrinkling of the lamina. Often, the leaf sheaths covering the pseudostem show longitudinal splitting above the ground level. But, sometimes this symptom may not appear. The affected plants may die completely in about 4-6 weeks after the appearance of yellow streaks on the petioles.

The vascular strands show discoloration varying from yellow to dark- brown, which is the characteristic internal symptom of the disease. The discoloration usually appears first in the outer leaf sheaths and extends to the vascular strands of the pseudostem. Vascular discoloration is more pronounced in the corms, but is not common in the roots. When the rhizome of an infected plant is cut transversely, the discoloration of the vascular bundles is distinctly seen as numerous, pin-point like dots all over the cut surface. The roots of affected plants become black and rotten. The suckers growing from the diseased corms are systemically affected and they wilt and die very soon (Fig. 71).

The causal organism. The mycelium of the fungus is hyaline, septate, much branched and mostly intracellular. Few hyphae may also be present in the intercellular spaces. The hyphae are largely confined to the vascular bundles, often filling the cavity of the vessels. The fungus produces three types of spores viz., macroconidia, microconidia and chlamydospores. The sporodochia bearing conidiophores and conidia emerge through the stomata on the petioles and leaves. The conidiophores are vertically branched. Macroconidia are borne at the apical ends of the main and lateral branches and are formed in succession one after another. They are thin-walled, hyaline, pedicellate, sickle-shaped, with both ends somewhat pointed, 2 - 5 septate, mostly 3-septate and measure 22.0 - 36.0 x 4.0 - 5.0µ in size. Microconidia are produced from the branches of conidiophores or from the tips of hyphae in very large numbers. They are single-celled or two-celled, thin-walled, hyaline, ovate or elongated and measure 5.0 - 7.0 x 2.5 - 3.0µ in size. Terminal or intercalary chlamydospores are formed from the hyphae, as well as from the conidial cells. They are oval or spherical, thick-walled and usually occur in pairs. They measure 7.0 - 13.0 x 7.0 - 8.0µ in size (Fig. 71).

The fungus is a facultative parasite. It can invade the host mainly through wounds in the corms or roots. After entry, the fungus develops extensively in the vascular tissue of the corm and then proceeds systemically to the leaf sheaths and pseudostem through the vascular system. The fungus colonizes the vascular bundles and produces masses of mycelium, which bear conidia and chlamydospores, filling the cavity of the vessels. The plugging of vascular elements by the fungus obstructs the translocation of water and nutrients to the aboveground parts of the plant leading to wilting and death of affected plants.

Mode of survival, spread and epidemiology. The fungus is soil-borne in nature. It can survive saprophytically in the diseased corms and other plant parts for prolonged periods and cause fresh infection. The chlamydospores can also remain in a viable state in the soil and diseased plant parts for a long time. The disease can be easily spread through spores present in the infected banana trash and soil, which may be carried in surface flooded water. Suckers used for planting from diseased areas to other places spread the disease easily. Contact of the roots of healthy plants with the roots of diseased plants carrying the spores also leads to fresh infection. The entry of the pathogen is mostly through wounds in the roots or corms, especially deep wounds up to the xylem vessels, caused incidentally during cultural operations or by soil-inhabiting pests, particularly nematodes.

Light textured, sandy loam soils, with acid reaction and low soil moisture of 25 % favor the occurrence and development of the disease. Ratooning of infected banana plants increases the disease incidence to a great extent and leads to continuous accumulation of soil inoculum.

‘Fungi’ including ‘mushrooms’ are ‘Thallophytes’, which do not possess chlorophyll and have been classified under the Kingdom - Myceteae. They do not have stems, roots and leaves and they lack a vascular conducting system as in the case of plants. They propagate by means of spores, either asexual or sexual. Though almost all the fungi are microscopic, the mushrooms are among the largest fungi and had attracted the attention Scientists and Naturalists of many countries dating back to centuries. The Greek word ‘mykes’, which means ‘cap’, was given to the mushrooms because of the ‘cap-like’ appearance of the pileus and the Greek word ‘Mycology’ (mykes = mushroom + logos = discourse) denotes the study of mushrooms. What we call mushrooms, are actually the sporocarps produced by several species of fungi, while the mycelium that produces them live in various types of substrata and obtain nourishment from them. Usually, the fleshy, macroscopic fruiting bodies or sporocarps produced by fungi belonging to Basidiomycetes and Ascomycetes are called ‘mushrooms’

The Romans attributed the appearance of mushrooms and truffles to lightning hurled by Jupiter to the earth. Even now in India and several other countries, people believe that mushrooms appear only after lightning and thunder. The Greeks believed mushrooms as ‘Food for the Gods’. The Romans supplemented mushrooms in the food of soldiers for strength and vitality. The much-priced mushrooms were supposed to be the food delicacy of the elite society of the Romans and Greeks in olden days. The Chinese consider mushrooms as a cure for many diseases and they believe that mushrooms increase the longevity. A number of medicines in all forms are prepared from mushrooms by the Chinese.

Statistics has originated as a science of statehood and found applications slowly and steadily in Agriculture, Economics, Commerce, Biology, Medicine, Industry, planning, education and so on. Sir Ronald A. Fisher, (1890 – 1962), who is called “the Father of Statistics”, drew many solid conclusions

1.2 Definition

Statistics is the science which deals with the collection of data, organisation of data (or) classification of data, presentation of data, analysis of data and interpretation of data, which are known as the statistical methods.

“Statistics is the science, technology and art of creating new knowledge.”

–RA Fisher.

“By statistics we mean, aggregate of facts affected to a marked

extent by multiplicity of causes numerically expressed enumerated or

estimated according to reasonable standard of accuracy collected in a

systematic manner for a predetermined purpose and placed in relation

to each other.”

– Professor Horace Secrist

Number line

Every real number occupies a position on the number line and conversely,

every point of the line can be matched with a real number.

Absolute value

The absolute value of modules of a number is equivalent to the value of that

number ignoring the sign. For example, the absolute value for -1 is 1, and the

absolute value of +1 is also 1.The absolute value is defined by the symbol

?x?.

Computers: Input and Output Devices

3.1 Input Device

Input devices are the pieces of hardware that allow to enter or input data into

a computer.

Keyboard

• A computer keyboard serves as a data input device.

• A keyboard is a device containing keys, each of which denotes an

alphabet, number, or number instruction that may be served to a computer

to do multiple tasks.

• The keyboard is a significant input device, both computers and laptops

use keyboards to enter commands into the computer.

Mouse

• Mouse is a pointing device.

• The mouse is used to open various files and programs by directly clicking

on the various icons on the system.

• A mouse has three buttons on top and one trackball on the bottom, which

are used to select and move the mouse.

• A touchpad is provided as an alternative for the mouse on laptops, which

aids in mouse pointer movement.

4.1 Principles of Economics

• ‘Economics’ word derived from two Greek words, oikos (a house) and

nemein (to manage) means ‘managing an household’

• Microeconomics: Study of the behavior of individual, small, isolated

and disaggregated units.

• Macroeconomics: Study of groups and broad aggregates of the economy.

• Adam Smith wrote the book- “An Enquire into the Nature and Causes of

Wealth of

• Nations” or in short “Wealth of Nations” in 1776.

• Adam Smith is known as father of modern economics.

4.2 Wealth Definition - Adam smith

• Adam smith (1723 - 1790), in his book “An Inquiry into Nature and

Causes of Wealth of Nations” (1776)

4.3 Welfare Definition - Alfred Marshall

• Alfred Marshall (1842 - 1924) wrote a book “Principles of Economics”

(1890)

• Alfred Marshall defined “Political Economy” or Economics is a study

of mankind in the ordinary business of life; it examines that part of

individual and social action which is most closely connected with the

attainment and with the use of the material requisites of well being”.

4.4 Scarcity Definition - Lionel Robbins

• Lionel Robbins published a book “An Essay on the Nature and

Significance of Economic Science” in 1932.

• Robbins defined, “economics is a science which studies human behaviour

as a relationship between ends and scarce means which have alternative

uses”.

Definition of Plant Pathology

‘Plant pathology’ may be defined as ‘the study of microorganisms and of the environmental factors that cause disease in plants; of the mechanisms by which these factors induce disease in plants; and of the methods of preventing or controlling disease and reducing the damage it causes’. Plant Pathology or ‘Phytopathology’ is a branch of Biological Science, which exclusively deals with plant diseases and various aspects connected with plant diseases. The term Phytopathology had been derived from the Latin language. The Latin word ‘PHYTON‘ means plants; ‘PATHOS‘ means suffering and ‘LOGOS‘ means Science. So, Phytopathology means the Science dealing with suffering plants. Trees, shrubs, grasses etc., whether cultivated or wild are termed as plants and they form the majority of the earth’s living environment. These plants, which are so vital for humans, animals and insects are vulnerable to attack by numerous microorganisms, called ‘plant pathogens’. Some environmental factors are also detrimental to the normal growth of plants, resulting in diseases. Diseased plants exhibit some type of abnormalities and these abnormalities are termed as ‘disease symptoms’. Depending upon the pathogens attacking the plants or adverse environmental factors the disease symptoms vary markedly.

The Science of Plant Pathology has four main objectives:

1. To acquire knowledge about biotic plant pathogens and abiotic environmental factors, which are responsible for causing diseases.
2. To know more about the occurrence and mode of spread of the pathogens on a large scale.
3. To study the interaction between the host and the pathogen with respect to environmental factors.
4. To adopt suitable methods of preventing or controlling the diseases, thereby reducing the damage caused by the pathogens.

Systematic knowledge about Plant Pathology will be of much help in protecting the plants from attack by the pathogens, thereby allowing the plants to grow and attain maturity according to their genetic potential.

‘Plant disease management’ involves the integration of various measures adopted to protect the plants by preventing them from contact with the pathogenic organisms, preventing the growth of the pathogens causing diseases, preventing sporulation of the pathogens and spread of diseases, destroying insect vectors responsible for transmitting diseases and such other prophylactic and curative measures. The ultimate aim of these measures is to avoid large-scale occurrence of diseases, reduce the severity of diseases and minimizing the losses caused by diseases. In disease management, importance should be given to control all the diseases attacking a particular crop at a particular time, especially those which occur in severe form in all the seasons and cause extensive damage to the crop and yield loss. Each and every crop is subjected to attack by one or more than one diseases. At the same time the control measures for controlling each of the disease may differ. In this respect a knowledge of the pathogen causing the disease, the symptoms of the disease, mode of infection and spread of the disease, the growth stage at which the crop is attacked, interaction between the host (crop) and the pathogen and weather conditions favorable for the occurrence and spread of the disease is absolutely necessary, so as to adopt suitable control measures to combat the disease and to minimize the damage to the crop, and reduce the yield loss.

The occurrence and spread of diseases are very much influenced by the environment, host and the pathogen. When the environmental conditions are suitable for the pathogen and not quite suitable for the host, the incidence of the disease is liable to be more. Further, if the host plants are not maintained properly and are weak, then they are more vulnerable to attack by the pathogen and the disease incidence may be severe. When the inoculum of the pathogen is present abundantly, the chances of attack by the pathogen are also more. Taking these facts into consideration, plant disease management is depicted as ‘manipulation of the disease triangle’ (Fig. 60)

All control measures should be aimed at protecting the plants from becoming diseased and not at curing the plants after they have become diseased. The principal methods adopted for controlling plant diseases are broadly categorized under five different heads viz. :