eChapters

Abstract

With the growing awareness on the benefits of organically cultivated food, biofertilization and biocontrol by plant-associated bacteria are being used as alternatives to chemical fertilizers and conventional control methods. It therefore becomes essential to continue surveying different agroecological niches to identify plant growth promoting bacteria suitable for each microenvironment. Species belonging to the genus Enterobacter are versatile colonizers of numerous environmental niches. Several species and strains from this genus have also been routinely recovered from the rhizosphere of crops such as rice, canola, cucumber, banana, potato, corn, tomato and cotton. These isolates have been studied and shown to have beneficial effects on plant growth and protective action against phytopathogens.

Abstract

The greatest challenge facing us in the coming years is to produce adequate amounts of basic necessities of food, feed, fibre, fuel and raw materials for the rapidly shrinking per capita agricultural land. One alternative is to make a sustainable use of existing marginal lands. In many regions of the tropics and sub-tropics, the need to use marginal low-input soils with usually inadequate nutrient(s) supply permits only very low or unreliable yields to be achieved. It is frequently not possible  to supply required amounts of mineral fertilizers or chemical pesticides because of the low purchasing power of the marginal farmers. In particular, it is not possible to compensate for the deficient nutrient supply and this constitutes a yield limiting factor. The role of soil microorganisms in sustainable productivity has been well construed. In recent years, root inhabiting (rhizozosphere) bacteria (rhizobacteria) is gaining importance.

Abstract

The phosphorus deficiency in soil is a major problem for agricultural production as phosphorus is one of the major constituents in energy metabolism and biosynthesis of nucleic acids and cell membranes. The phosphorous present in soil is an important macronutrient for the growth and development of the plants. The phosphorus occurs in two forms in soil, organic and inorganic. The phytates (salts of phytic acid) constitute the major form of organic phosphorus other than nucleic acids, phospholipids and other compounds in soil. Phytate-phosphorus is not readily available to plants due to its chelation with metal ions forming insoluble complexes or adsorbed to soil particles. Phosphate solubilizing and phytate hydrolyzing microorganisms, bacteria and fungi, are ubiquitous in cultivated, wetland, grassland and forest soils, which play an important role in supplying soluble phosphorus to plants. Microbes hydrolyze organic forms of phosphorus by secreting phytases and acidic/alkaline phosphatases. By genetic engineering, several attempts have been made to develop transgenic plants which are able to utilize phytates as sole source of phosphorus for their growth and development. This review focuses on the applicability of microbial phytases in promoting the growth and development of various crop plants.

Abstract

The structure and function of proteins involved in plant-microbe interactions is investigated through large-scale proteomics technology in a complex biological sample. Since the whole genome sequence are now available for several plant species and microbes, proteomics study has became easier, accurate and huge amount of data can be generated during plant-microbe interactions. Proteomics approaches are highly important and relevant in many studies and showed that only genomics approaches is not sufficient as much significant information are lost as the proteins and not the genes coding them are final product which is responsible for the observed phenotype.

Introduction

Biological nitrogen fixation (BNF), generally found in legumes, is a valuable nature’s gift through which atmospheric nitrogen is fixed by symbiotically associated rhizobia that make it available to plants. Among cereals, rice (Oryza sativa) is an important staple food crop that feeds a large proportion of the world population [1]. There is tremendous pressure on agriculturists worldwide to increase the yield to meet growing consumption to feed a world population increasing day by day. However, unlike symbiotic plant–microbe interactions commonly observed in legumes, in several cereal crop plants including Oryza sativa, endophytic associations have been observed [2-8].

Abstract

While, life on Earth is dependent on microbes for many essential services, microbes are intimate partners in virtually every life process of plants by way of mobilization/acquisition of nutrients, out-competition and antagonism of pathogens, plant stress alleviation, plant growth promotion, co-metabolism, degradation of toxins, etc. Exploitation of such interactions between microbes and plants and optimization of plant microbiome could allow farmers to apply less chemical fertilizer, and pesticides besides improving overall plant health which paves the way for sustainable development. What is less appreciated, and less well understood, is the mechanism of microbes exerting such benefits to the plants. A greater understanding of how plants and soil microbes live together, communicate, build innate plant immunity, triggers hormone synthesis and benefit each other can therefore provide new strategies to improve plant productivity, while helping to protect the environment and maintain global biodiversity.

1    Introduction to Patent Laws    540

2.    An Overview of the Patenting Process    541

    2.1.    Inventor’s disclosure, 542
    2.2.    Patentability search, 542
    2.3.    Patent application preparation, 542
    2.4.    Patent application amendment, 542
    2.5.    Patent application examination, 543
    2.6    Main parts of a patent, 543
    2.7.    Granting of patent, 544
    2.8.    Date and term of patent, 544
    2.9.    Provisional specification, 544
    2.10.    Complete specification, 545
    2.11.      Cost of patenting, 545

1.    Introduction    496

2.    Strain Development Technologies    496

    2.1.    Screening of natural variants of microorganisms, 496
    2.2.    Genetic manipulation of microorganisms, 498
        2.2.1.    Random mutagenesis and selection, 498
        2.2.2.    Conjugation, 504
        2.2.3.    Transduction, 504
        2.2.4.    Transposition, 506
        2.2.5.      Hybridization, 507
        2.2.6.    Rare Mating, 509
        2.2.7.    Cytoduction, 510
        2.2.8.    Protoplast fusion, 511
        2.2.9.    Transformation, 511
        2.2.10.    Gene cloning and transformation (Recombinant DNA technology), 513

1.    Introduction    468

2.    Biofuel Cell    470

    2.1.    Microbial-based Biofuel Cells, 471
        2.1.1.    Microbial bioreactors producing H2 for conventional fuel  cells, 475
        2.1.2.    Microbial fuel cells producing electrochemically active metabolites in  
                the anodic compartment, 476
        2.1.3.    Microbial fuel cells operating in the presence of artificial electron relays, 477
        2.1.4.    Microbial fuel cells producing electricity during wastewater treatment, 483
        2.1.5.    Microbial fuel cell producing  electricity from acetate or butyrate, 484

1.     Introduction    424

2.    Conventional Methods of Hydrogen Production    426

3.    Biological Methods of Hydrogen Production    429

    3.1.    Hydrogen production by biophotolysis of water, 430
        3.1.1. Photolysis by cyanobacteria (Blue green algae), 430
            3.1.1.1. Nitrogenase dependent hydrogen production, 434
            3.1.1.2.  Hydrogenase-dependent hydrogen production, 437
            3.1.1.3.  Factors affecting  hydrogen production by cyanobacteria, 440
            3.1.1.4.   Bioreactors for cyanobacterial hydrogen production, 443
            3.1.1.5. Future prospects for cyanobacterial hydrogen production, 446

1.    Introduction    392

2.    Landfill Gas    393

3.    Biogas    394

    3.1.    Benefits of biogas, 394
    3.2.    Potential of biogas, 395
    3.3.    Biogas production system, 396
        3.3.1.    Raw materials, 396
        3.3.2.    Biogas technology, 398
        3.3.3.    Process of anaerobic fermentation for methane generation, 400
        3.3.4.    Conditions for anaerobic fermentation, 404
        3.3.5.    Sludge-algae-methane system, 407
        3.3.6.    Biogas plant, 408

1.    Introduction    360
2.    Feedstocks for Biodiesel Production    361

    2.1.    Fats and oils, 362
    2.2.    Alcohols, 363
    2.3.    Catalysts and neutralizers, 367

1.    Introduction    302
2.    Raw Materials for Alcohol Production    304

    2.1.    Sugary substrates, 306
    2.2.    Starchy residues (cereal grains), 309
    2.3.    Cellulosic materials (crop residues), 314

3.    Microorganisms for Alcohol Production    316

    3.1.    Comparision of ethanol production by bacteria and yeasts, 318

1.    Introduction    272
2.    Alcohols    273

    2.1.    Methanol, 274
    2.2.    Ethanol, 277
    2.3.        Butanol, 283

3.    Biodiesel    284
4.    P-series fuels

1.    Introduction    232
2.    Photosynthesis and Biomass Yields    232
3.    Biomass Properties    233
    3.1.     Polymeric and chemical composition, 233
    3.2.     Fuels analysis, 235
    3.3.     Physical properties, 236

1.    Introduction    174
2.    The Thermodynamic and Mechanistic basis of Cellular Metabolism    174

    2.1.      Adenosine triphosphate, 175
    2.2.    Coenzyme A, 176
    2.3.    Modes of ATP synthesis, 177

3.      Components of Electron Transport Chain    181

    3.1.    Electron carriers in ETC, 182
    3.2.    Complex I - NADH dehydrogenase (NADH coenzyme Q reductase), 185
    3.3.    Complex II - Succinate - coenzyme Q reductase, 187
    3.4.    Complex III - Coenzyme Q - cytochrome c reductase, 187
    3.5.    Complex IV - Cytochrome c oxidase, 188
    3.6.    ATP synthese, 188

1.    Introduction    129
2.    Soil Microbiology    129

    2.1.    Bacteria, 130
    2.2.    Fungi, 132
    2.3.    Algae and Cyanobacteria, 132
    2.4.    Protozoa, 132
    2.5.    Viruses, 135

3.    Water Microbiology    133
4.    Microbial Associations    133

    4.1.    Neutral interactions, 133
    4.2.    Positive interactions, 133
    4.3.    Negative interactions, 133

1.    Introduction    71
2.    Microorganisms in Food Industry    72
    2.1.    Microorganisms as the agents of fermentation in  
        traditional fermented foods, 73
    2.2.    Microorganisms as the source of food, 83
    2.3.    Microorganisms as a source of food supplements, 86

3.    Microorganisms in Pharmaceutical Industry    92

    3.1.    Antimicrobial agents from microorganisms, 92
    3.2.     Microorganisms as probiotics, 97
    3.3.    Microbial enzymes in  pharmaceuticals, 98
    3.4.    Mushroom nutriceuticals, 98

1.    Introduction    3
2.    History and Scope of Microbiology    4
    2.1.    Controversy over the origin of microorganisms, 5
    2.2.    Germ theory of fermentation, 6
    2.3.    Germ theory of disease, 6
    2.4.    Development of laboratory techniques and pure cultures, 7
    2.5.    Discovery of immunization, 7
    2.6.    Discovery of protection against infection, 8
    2.7.    Discovery of chemotherapeutic agents, 8
    2.8.    Microorganisms as geochemical agents, 9

Management of paddy straw is one of the important problems being faced by the farmers. Burning of rice straw in the field is the traditional method being practiced by most of the farmers, which causes atmospheric pollution and nutrient loss. There are three options available to manage the straw viz. i) burning the straw in the field, ii) collecting/baling the straw from the field, and incorporation of straw in the field. If rice straw is not burnt then baling may provide an attractive economic environmentally safe option. Manual collection of paddy straw is a laborious job and also storing the large volume of straw is another problem. As for as paddy straw is concerned, it has higher silica content so animals do not prefer it.

Harvesting and threshing are the key most important operations in the entire range of field operations required in any crop production system. Both of these operations remain still the most important operations as fruit of labour depends upon them. Crops are harvested after normal maturity with the objective to take out grain, straw, tubers etc without much loss.  It involves cutting / digging/ picking, laying, gathering, curing, transport and stacking of the crop.  Harvesting of major cereals, pulse and oilseed crops are done by using sickle whereas tuber crops are harvested by country plough or spade (Fig. 8.1).

The application of agricultural chemicals for control of insects, pests, fungi, weeds and plant diseases plays an important role in crop production. Before 1980 few chemicals were known for control of plant pests.  The chemical pesticides have played an important role in the rapid advancement of agricultural production. Chemical pesticides are getting popular due to non availability of labours especially for weeding operation during kharif season. The chemical pesticides and herbicides are applied with the help of different types of sprayers and dusters.

Fertilizers are required where soils are deficient in plant food elements. When land is planted to crops over a long period of time, the plant food elements slowly get reduced and productivity of crop goes down. Sandy soil looses plant food elements rapidly because heavy rainfall or application of irrigation water leaches these elements out from the soil. Adding chemical fertilizer increases fertility of soil. Principally nitrogen, phosphorous and potassium are added to the soil to promote greater yields. Uniform distribution and proper placement of fertilizer in the soil have become increasingly important factor in providing maximum crop response at minimum cost. Placing the fertilizer near the seeds at the time of sowing results in more effective utilization of nutrients. In the row crops side dressing of fertilizer is done which has immediate benefit when placed in the moist soil within the root zone.

Weeds are a serious menace and these reduce the quality and yield of crops substantially. Chemical as well as mechanical methods are being used to control the weeds. The weeding was traditionally done by “khurpa” up to mid 60s. This tool requires its operation in a sitting posture, which reduces the work rate. The use of long handled tools like “kasola” became popular because these allowed their operation in a standing posture, which increases the mobility and thus the work rate. Weeder is a mechanical device to remove the weeds (unwanted plants) from the cultivated crop. A wide variety of weeders are used in the countries, which may be categorized in three groups viz. manual weeder, animal or tractor drawn weeder and power weeder or self-propelled rotary weeder (Singh, 2007; Pandey et al., 1997; Pandey and Ganesan, 2005).

The seed drills and planters developed and manufactured in advanced countries are designed to meet the requirements of farmers for the different crops and agro-climatic conditions. These machines are capable of operating at high working speed, cover the large area per unit time and provide the desired plant emergence and stand in the fields. The machines are available to handle the seeds of cereals, pulses, oil seeds and other crops widely grown in the developed countries. In developing countries even though these machines can be made available but they are beyond the reach of small farmers. The level of mechanization of sowing and planting is at a very low level.

Tillage operations are the basic operation, which need to be performed at proper moisture and temperature condition (climatic factor) to attain high degree of germination and better plant growth. Tillage may be defined as mechanical manipulation of soil for the purpose of germination and plant growth but it also does the followings:

Introduction

The work on field drains and farm ditches are essential for providing proper irrigation to the crop. Leveling of field is equally important for smooth operation of various field activities including irrigation. Land grading in irrigated agriculture helps in uniform application of water, better water regulation and saving in irrigation time. Land grading helps in conservation of soil and moisture under rainfed conditions. It provides desired surface drainage under irrigated and rainfed conditions. Land leveling helps in the smooth operation of sowing/planting and harvesting equipment.

The Indian agriculture is characterized by agro-ecological diversities in soil, rainfall, temperature and cropping system. Besides favorable solar energy, the country receives about three trillion cubic meter of water from rainfall. Of the total geographical area of 329 million hectares the net sown area has remained at about 140-142 million hectares during the last 40 years. The gross cropped area however has increased to about 200 million hectare in 2011-2012 (Anonymous, 2013). The total operational holding is estimated at 105 million with average size of the holdings of 1.6 ha. The Indian agriculture is not only characterized by small fragmented land, but also hill farming and shifting cultivation are also practiced. Out of an estimated 142 m ha net cultivated area around 40% is irrigated and rest is rain fed. About 65% of the population depend upon agriculture for their livelihood.

Introduction

On 29 January 2000, the Conference of the Parties to the Convention on Biological Diversity adopted a supplementary agreement to the Convention known as the Cartagena Protocol on Biosafety. The Protocol seeks to protect biological diversity from the potential risks posed by living modified organisms resulting from modern biotechnology. It establishes an advance informed agreement (AIA) procedure for ensuring that countries are provided with the information necessary to make informed decisions before agreeing to the import of such organisms into their territory. The Protocol contains reference to a precautionary approach and reaffirms the precaution language in Principle 15 of the Rio Declaration on Environment and Development. The Protocol also establishes a Biosafety Clearing-House to facilitate the exchange of information on living modified organisms and to assist countries in the implementation of the Protocol.

Chapter I
Preliminary 
1. Short Title and Commencement 
    (1)    These rules may be called the Protection of Plant Varieties and Farmers’ Rights Rules, 2003.   
    (2)    They shall come into force on the date on which the Act shall come into force.   

2. Definitions 
        In these rules, unless the context otherwise requires, -   
    (a)    “Act” means the Protection of Plant Varieties and Farmers’ Rights Act, 2001(53 of 2001);

Introduction

In order to provide for the establishment of an effective system for protection of plant varieties, the rights of farmers and plant breeders and to encourage the development of new varieties of plants it has been considered necessary to recognize and protect the rights of the farmers in respect of their contribution made at any time in conserving, improving and making available plant genetic resources for the development of the new plant varieties. Moreover to accelerate agricultural development, it is necessary to protect plant breeders’ rights to stimulate investment for research and development for the development of new plant varieties.

BE it enacted by Parliament in the Fifty-sixth Year of the Republic of India as Follows :
 
    1.    (1) This Act may be called the Patents (Amendment) Act, 2005. 
        (2) Sub-clause (ii) of clause (a), and clause (b), of section 37, sections 41,42,47,59 to 63 (both inclusive) and 74 shall come into force on such date as the Central Government may, by notification in the Official Gazette, appoint; and the remaining provisions of this Act shall be deemed to have come into force on the 1st day of January, 2005.

Chapter I: Preliminary

1. Short title, extent and commencement
 
    (1)    This Act may be called the Patents Act, 1970. 
    (2)    It extends to the whole of India. 
    (3)    It shall come into force on such date as the Central Government may, by notification in the Official Gazette, appoint: 
PROVIDED that different dates may be appointed for different provisions of this Act, and any reference in any such provision to the commencement of this Act shall be construed as a reference to the coming into force of that provision.

Intellectual Property Right, IPR is a general term covering patents, registered design, trademarks, copyrights, layout design of integrated circuits, trade secrets, geographical indicators and competitive practices in contractual license.

THE SEEDS BILL, 2004
A
BILL
 to provide for regulating the quality of seeds for sale, import and  export and to facilitate production and supply of seeds of quality and for matters connected therewith or incidental thereto.

Introduction

Indian Agriculture has made enormous strides in the past 50 years, raising foodgrains production from 50 million tonnes to over 200 million tonnes.  In the process, the country has progressed from a situation of food shortages and imports to one of surpluses and exports.  Having achieved food sufficiency, the aim now is to achieve food and nutritional security at the household level.

The increase in agricultural production, however, has brought in its wake, uneven development, across regions, crops, and also across different sections of farming community.  In the decade of the ‘nineties’, a marked slackening in the pace of growth has occurred, pointing to the need for infusing a new vitality in the agricultural sector.

S.O.867 (E) – In exercise of the powers conferred by sub-section (1) of section 3 of the Destructive Insects and Pests Act, 1914 (2 of 1914), and in suppression  of Plants, Fruits and Seeds (Regulation of import into India) Order 1984, except as respects things done or omitted to be done before such suppression, the Central Government hereby makes the following order for the purpose of prohibiting and regulating the import into India of agricultural articles mentioned herein, namely: -

Part I - Preliminary

    1.    Short title. – These rules may be called the Seeds Rules, 1968. 
    2.    Definitions. – In these rules, unless the context otherwise requires,- 
        (a) “Act” means the Seeds Act, 1966 (54 of 1966); 
        (b) “advertisement” means all representations other than those on the label, disseminated in any manner or by any means relating to seed for the purposes of the Act; 
        (c)  “certification sample” means a sample of seed drawn by a certification agency or by a duly authorised representative of a certification agency established under section 8 or recognized under section 18 of the Act; 
        (d) “certification tag” means a tag or label of certain design to be specified by the certification agency and shall constitute the certificate granted by the certification agency; 

BE it enacted by Parliament in the Seventeenth Year of the Republic of India as follows:

Short Title, Extent and Commencement
    1.    (1) This Act may be called the Seeds Act, 1966.
        (2) It extends to the whole of India. 
        (3) It shall come into force on such date as the Central Government may, by   notification in the Official Gazette, appoint, and different dates may be appointed for different provisions of this Act, and for different States or for different areas thereof.

Cotton is a major crop of India grown in about 9.0 million hectares.This is the largest cotton area in the world. Thus, India ranks Ist among cotton growing countries in the world in terms of area. However, average cotton yields in India have been 320 kg/ha as compared to world cotton yield average of 580 kg/ha. Thus, cotton production in India represents only about 13% of the total world production whereas India accounts for approximately 20% of the world’s total cotton area. Obviously, yield levels in India are low compared to world average. The low yield levels in India are partly due to heavy losses from insect pests, particularly cotton bollworm complex.

Ministry of Environment & Forests Notification

New Delhi, the 5th December, 1989

Rules for The Manufacture, Use, Import, Export and Storage of Hazardous Micro Organisms Genetically Engineered Organisms or Cells
(To be notified under the EP Act, 1986)
G.S.R. 1037(E) : In exercise of the powers conferred by sections 6, 8 and 25 of the Environment (Protection) Act, 1986 (29 of 1986) and with a view to protecting the environment, nature and health, in connection with the application of gene technology and micro-organisms, the Central Government hereby makes the following rules, namely:-

The genetically engineered (GE) seeds developed using recombinant DNA technology often referred to as transgenics or genetically modified organism (GMOs) provide an usually adaptable, scale neutral technology for the farmers. Even small farmers can benefit from such seeds provided the seeds are made available at reasonable cost. While growing such seeds the existing crop management practices are usually sufficient. The transgenics or GMOs are also defined as those organisms with a gene or gene construct of interest that has been introduced by molecular or recombinant DNA techniques. These exclude organisms produced by conventional breeding as well as organism produced by rearrangement of genetic materials by physical methods or by chemical means. Thus, GMO’s carry trangene(s) which when integrated and expressed stably and properly, confer either a new trait to the organism which was hitherto not present (such as insect resistance), or enhance an already existing trait such as nutritional quality (Prasana 2001).

Many developing countries, for example India, China, Thailand, Brazil, Mexico, Egypt and South Africa, utilise the so-called modern biotechnology, based on genetic engineering and genomics. Agricultural biotechnology is the most widespread biotechnology in developing countries, but only a few of them are able to carry out all of the research and development activities leading to the commercialization of genetically modified seeds. These include basic research in molecular and cell biology and genetics, greenhouse and field trials according to  internationally agreed biosafety standards, risk assessment and management, respect for intellectual property rights relating to the transferred genes and to the creation of new crop varieties, production of genetically modified (GM) seeds by private corporations or working in cooperation with the public agricultural research sector, extension activities aiming at delivering the new seeds to the farmers and biovigilance in the fields of GM crops so as to detect any abnormalities or any hazards caused to the environment and to conventional crops (Sasson and Elliot, 2004).

Squashes and pumpkins are vegetable crops of the genus Cucurbita. They are grown in temperate, subtropical and tropical regions of the world. These crops are common elements in home gardening and subsistence agro-ecosystems in most countries and are produced on commercial scale in some countries. The economic botany, genetics and evolutionary history of Cucurbita has been reviewed by Whitaker and Davis (1962) and Whitaker (1974).

Hybrid vigour in plants has long been noted, and the first suggestion that it be exploited in vegetables was by Hayes and Jones in 1916. F1 hybrid eggplants were used on commercial scale in Japan before 1925. Demonstration of the value of hybrids in corn in the early 1920’s gave impetus to a few exploratory studies in other crops. Methods of its application to large scale field production of hybrids in vegetable crops were first proposed in 1932 using the self incompatibility system in cabbage and in 1943 using the cytoplasmic genetic male sterility system in onion. Today hybrid varieties are common in several vegetable crops viz., sweet corn, onion, tomato, summer squash, ordinary cabbage, cucumber, watermelon, muskmelon, asparagus, sweet pepper, chilli pepper, spinach, broccoli, Chinese cabbage, eggplant, Brussels sprout, Chinese radish, red beet, celery, bottle gourd, bitter gourd, okra, etc. India figures prominently in commercial exploitation of heterosis in vegetable crops like cabbage, tomato, okra, watermelon, muskmelon, eggplant, bottle gourd, bitter gourd and cucumber.

The information under this section is primarily based on Yordanov (1983). It is almost unanimously accepted that heterosis manifestation in tomato is in the form of the greater vigour, faster growth and development, greater earliness, and productivity, higher resistance to disease and adaptability unfavourable environmental conditions. The first step towards a large scale extension of hybrid tomato cultivars in the practice and proper organization of hybrid seed production took place in Bulgaria. After the second world war tomato heterosis breeding developed quickly in the Netherlands, England France, USA, Japan and other countries. In India, tomato hybrid cultivar on commercial scale was introduced in 1973 by Indo American Hybrid Seed Company.

Floral Biology and Crossing

Pearl millet spikelets bear 2 types of florets, one being bisexual and the other staminate. A singIe pistil with 2 feathery and 3  anthers is enclosed between the lemma and palea. The unisexual staminate florets are sessile and borne below the bisexual flowers. These have 3 anthers and lack the female organs. Pearl millet is a highly protogynous species and thus  highly cross pollinated.
 
The time of panicle exertion from boot leaf varies in inbreds and hybrids. Bhatnagar and Kumar (1960) observed that spike takes 6 days to emerge from the sheath with the maximum emergence on the fourth or fifth day. The stylar branches protrude first from the florets at the tip of the head and gradually proceed downwards. Most of the stylar branches on the earheads emerge by the third day. There exists a great variation in the time taken for the complete emergence of the styles in the hybrids than in the inbred lines (Tewari et al.,1971). Anthesis in pearl millet is completed in two phases. The first involves the bisexual florets while the second involves staminate florets. It has been generally observed that the anthers in the sessile male florets emerge 2-3 days after the anthers have emerged in the bisexual florets. Thus most heads continue to shed pollen for 4-6 days.The largest number of anthers emerged between 8 PM and 2 AM. Environmental factors like temperature and humidity have significant role in the anther emergence.

Hybrid Rice

People’s Republic of China announced the successful development and use of F1 rice hybrids in the late 1970s. The first hybrid rice combinations were put into commercial production in China in 1976. Since then commercial exploitation of hybrid rice attracted the attention of researchers around the world. It is accepted that about 20% yield advantage of hybrid rice would be usually required to meet the extra cost of seed production and the future rice demands of a growing world population. Realizing the prospects of hybrid rice, IRRI intensified research on this and organized an ‘International Symposium on Hybrid Rice’ on 6-10 October 1986 at the Hunan Hybrid Rice Research Centre, Changsha, China where Prof. Yuan Longping and his co-workers had made their names in development of hybrid rice. The proceedings were brought out in form of a book entitled ‘Hybrid Rice’ in 1988 by International Rice Research Institute, Philippines. This book documents the information exchanged, and presents for the first time, in English, much of the Chinese literature on hybrid rice.

Hybrid technology is one of the options to boost crop productivity. Hybrids give more yield than improved varieties under optimum crop production conditions. Further, uniform size, earliness, better adaptability to adverse environments, better transportability due to better keeping quality and resistance to stresses are certain additional advantages of growing hybrids with better monetary return to the growers. Hence in coming years, hybrid technology has to go a long way in our country to meet the future challenges (Kalloo et al., 2000). Thus, it is pertinent to have an overview of the methods of the hybrid seed production technology. Various methods are as follows:

The purpose of seed storage is to preserve planting seed from one season  to the next. Further, the objective of seed storage is to maintain seed quality for the longest duration possible. 

Relative Humidity and Temperature Influence Seed Storability

The two most important factors that influence the storability of seed are relative humidity and temperature. The effects of relative humidity and its subsequent effect on seed moisture and the temperature of the storage environment are highly inter- dependent. Harrington (1963) gave two useful thumb rules for relative humidity and temperature in reference to storage life of the seed. These rules are as follows :