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Defining-Commercial Plant Breeding

The term commercial plant breeding originates by putting prefix ‘commercial’ before ‘plant breeding’ and is used as an adjective to plant breeding which surely is a noun. Naturally, commercial plant breeding remains largely plant breeding with slight twist that commercial plant breeding aims at delivering commercial products to be delivered to the end users that is the farmers as per the need of the consumers/markets. Thus, the farmers plant those products (open-pollinated cultivars and hybrids) which are easily accepted by the consumers and which are easy to be handled by the traders as the products reach to the traders and then from traders to the retailers and ultimately to the consumers. Along with consumers’ acceptance, these kinds of products must meet certain level of yield, maturity and resistance/tolerance to diseases and pests. Accordingly, these are designed and bred by the commercial seed companies which operate as per demand of the markets. Private seed companies operate on a business model and generate their own revenue to keep the companies running and therefore these seed companies are bound to design and breed commercially viable products. Thus, all plant breeding activities which occur at the research farm and laboratory of private seed companies aimed at designing and delivering commercially viable products are called as commercial plant breeding activities. While designing such project and running the plant breeding activities at the research farm and laboratories of the private seed companies, the emphasis has to be on ‘how to do’ and ‘how quickly to do’ rather than ‘why to do’. ‘Why to do’ issue is not totally ignored and this gets due consideration while formulating the research project based on extensive deliberations between various departments, namely, R&D, Sales and Marketing, Product Development, and Seed Production.

The term commercial plant breeding is generally not in use in public sector research institutes and the agricultural universities and certainly not in class room teachings and discussions while teaching courses on plant breeding and related courses under the domain of plant breeding. There the focus is on theory in contrast to applications which form the backbone of commercial plant breeding as practiced by the commercial organizations such as private sector seed companies which have to earn revenue by selling the products to meet the operational expenditure of running the companies and also to earn profit to run the activities of the company on long term basis in a sustainable manner and to invest in R&D. Therefore, a working definition of commercial plant breeding could be as follows.

1. Introduction

Nursery raising is as old as agriculture and has many advantages compared to direct seeding in special situations like vegetable cultivation and other high value plants. There are several types of nurseries to cater different crop species like ornamental plants, fruit plants, forest plants and vegetables, although the fundamental concept of all these nurseries is the same. With the advent of drip system, soilless media and plasticulture the nursery system has also become more modern and automated. A nursery is a area or place for growing and looking after young seedlings/plants until they are ready for planting in the main field. 

The Government of India has established boards for important crops. The boards are statutory bodies which help in guiding the production and export. The main objectives for setting up the boards are -

To monitor and promote the export of primary items.

To empower the producers by providing trainings and close guidance.

To conduct research to improve the commodity, e.g. Central Coffee Research Institute, Coir Research Institute etc.

To advise the government on policy matters such as price fixing, fixing quota for export and signing trade agreements.

To promote the commodity by opening offices and outlets in India and abroad.

To showcase the commodity by participating in trade fairs and exhibitions.

1. FRUIT CROPS

1.1 Physiological Disorders

A wide variety of physiological disorders are found in apple fruit, but the susceptibility varies with variety, pre-harvest factors and post harvest conditions. Disorders can be considered in three categories:

1. Disorders that develop only on the tree: Most important is watercore in which intercellular air spaces in the core and cortical tissues become filled with liquid, Presence of watercore in fruit at harvest creates problems in certain varieties such as ‘Delicious’ because fruit with moderate or severe watercore can develop breakdown during storage.
2. Disorders that develop on the tree and during storage: Bitter pit is a disorder characterized by development of discrete pitting of the cortical flesh. Rapid cooling, CA storage and application of postharvest calcium drenches may be able to reduce its occurrence.
3. Disorders that develop during storage: Senescent breakdown disorders, chilling disorders and disorders associated with inappropriate atmospheres during storage are common disorders. The most common disorders associated with temperature and atmospheres are superficial scald, soft scald, low temperature breakdown, brown core, internal browning, low O2 injury, and high CO2 injury.

A

Abnormal seedling: Abnormal seedlings are those seedlings which do not show the capacity for continued development in to normal plants when grown in good quality soil under favourable conditions of water supply, temperature and light.

Abortion: Loss of reproductive structures (e.g. a flower or an ovule) during development or arrest of development of any organ so that it remains imperfect or fails to reach maturity.

Absolute humidity: The amount of water vapour present in a given volume of atmosphere, usually expressed in g water per kg dry air, or g water per cubic meter air.

ABSTRACT

The tissue culture derived black pepper plants of variety Panniyur 4 were compared with conventional propagules for its vegetative growth and field performance. The in vitro derived plants recorded better rooting, survival rate and shoot growth than the conventional propagules. More than 90% of the TC derived plants recovered after primary hardening and 99% recovered after secondary hardening, while it was only 70% in conventional propagules at both the hardening stages. The secondary roots developed in TC derived plants were observed to be far more superior in number and length. The initial growth rate in terms of plant height, number and size of leaves was much better in TC derived plants. The TC derived plants developed numerous bearing shoots - laterals - in the first year of growth and started bearing in the first year itself. The performance was superior to conventional propagules in which production of laterals and bearing begins much later. Thus the performance of TC derived plants was rated as superior to conventional propagules.

ABSTRACT

Protoplast isolation of Piper nigrum L.and Piper colubrinum Link. was attempted using axenic leaves at two different osmotic potentials viz. 0.60 and 0.65 molar (M) osmoticum. In Piper nigrum, highest protoplast yield (6.90 x 10⁴ protoplasts ml^-1) was observed in the enzyme combination 1.40 per cent cellulase and 0.310 per cent pectinase while in Piper colubrinum, highest protoplast yield (13.0 x 10⁴ protoplasts ml^-1) was observed in the enzyme combination 1.0 per cent cellulase and 0.217 per cent pectinase during 21 h of digestion. In both the species, 0.6 M osmoticum was found to be optimum to maintain the osmotic potential of the isolation solution. Filtration-centrifugation technique was found to be superior in purifying the protoplasts of Piper species compared to sucrose floatation method. Centrifugation at 1000 rpm for three minutes was found to be best in purifying Piper nigrum protoplasts. For purifying Piper colubrinum protoplasts, 600 rpm for three minutes was found optimum. The protocol developed for protoplast isolation in Piper species can be used for biotechnological means like somatic hybridization between the two and gene transfer to develop foot rot resistant black pepper lines.

The food plants of world are damaged by more than 10,000 species of insects, 30,000 species of weeds, 1,00,000 diseases (caused by fungi, bacteria, viruses and other microorganisms and 1000 species of nematodes (Hall, 1995). The global losses due to various categories of pests vary with the crop, geographic location and weather. Total yield losses from different pests to all the crops have been estimated to be US$ 500 billion worldwide (Oerke et al., 1994). In India, the current losses due to insect pests in principal field crops have been estimated to be Rs. 6, 89,400 million (Dhaliwal et al., 2004). In addition, there is loss of Rs. 60,000 million due to insect pests during storage. Thus, total losses to major crops and food grains in storage caused by insect pests are estimated to be Rs. 750 billion annually (Dhaliwal and Arora, 2006). Among regions, losses in Asia and Africa almost reaches 50 percent whereas in Europe (28.2%), North America (31.2%) and Oceania (36.2%) are below average. Losses due to animal pests in Asia (18.7%) are almost double those in developed countries and losses from weed competition in Africa and Asia are approximately double than those in Europe (Oerke et al., 1994). To combat such heavy losses mostly chemical pesticides are used by the farmers but indiscriminate use of pesticides has led to severe ecological consequences like destruction of natural enemy fauna, effect on non target organisms, residues in consumable products including packed pure and mineral water and ultimately resistance to the pesticides, to which we solely rely. Insecticides are always required to suppress rapidly expanding insect pest populations. Strategies should be employed to increase efficiency and accelerate insect mortality by combining microbials with sub lethal doses of chemical insecticides and botanicals. Biointensive pest management (BIPM) is the recent trend in Indian farming and attracting the farmers for higher income to their produce. This has resulted due to increased awareness among the end users and concerns about the deteriorating ecological situations among the eco-campaigners.

Microbial pesticides consist of disease causing microorganisms, which are disseminated in the pest populations in large quantities in a manner similar to application of chemical pesticides. It includes bacteria, viruses, fungi, nematodes and some protozoans. Pathogens may exert controlling effect by means of their invasive properties, toxins, enzymes and other substances (Lewis, 2006). The use of microbial insecticide has been proved to be a viable alternative to chemical insecticides, especially in management of forest insect pests. The combination of particular active ingredients and their ability of replication in host populations in the fields define the major differences between microbial insecticides and chemical insecticides. These differences have practical implications for their use in insect pest management programmes.

Composites defined as advanced generation populations maintained by random mating in the material constituted through mixing of equal quantity of seeds of crosses showing less inbreeding depression in F2 over F1. The components of composites inbreds, open-pollinated populations, locally available open-pollinated cultivars, hybrids, advanced generation lines, improved populations. Mixing the seeds of several phenotypically outstanding lines produces a composite variety and encouraging open pollination to produce crosses in all combinations among, the mixed lines. The lines used to produce a composite variety are rarely or not tested for combining ability with each other like as done in case of synthetics where the combining ability of the component lines is invariably tested for GCA. Composite are commercial varieties and are maintained by open - pollination in isolation. While mixing the seeds of various genotypes, care should be taken that the component lines are similar in maturity height, seed size, colour, etc. so that the composite maintained through random mating in isolation manifests a reasonable degree of phenotypic uniformity. The variety is maintained by open pollination. Farmers can use their own seed for 3 to 4 years.

1. INTRODUCTION

Juices and pulps are produced from a wide variety of fruits and vegetables around the world, while some medicinal plants and herbs are also used for preparation of extract of beneficial bioactive compounds. These juices and extracts contain very high proportions (upto 75-90%) of water. Due to their seasonal nature, these products can not be produced round the year in various parts of the world. Preservation, storage, transportation and marketing of single strength juices, pulps and extracts is not at all economical due to the presence of large quantities of water. Under these circumstances, the technology of concentration offers many advantages.

In chemistry, concentration, as a state, may be defined as “the abundance of a constituent divided by the total volume of a mixture” and can be mathematically explained in four types i.e. mass concentration, volume concentration, molar concentration and number concentration. Generally, the term concentration can be applied to any mixture (solid or liquid) but most frequently it refers to the presence of solutes in solvents. Mass concentration is defined as mass/volume (m/V) of mixture and represented in kg/m³, volume concentration as volume of a constituent divided by the volume of all constituents of the mixture (v/V) and represented in m³/m³, molar concentration as moles of a constituent divided by the volume of all constituents of the mixture (n/V) and represented in mol/m³, while, number concentration is defined as the number of entities of a constituent in a mixture divided by the volume of the mixture (N/V) represented in 1/m³.

In food technology or fruit juice industry in particular, concentration refers to a process of separation of water (or any other solvent) from the solids of the pulp, juice, extract by making use of any of the three basic methods i.e. evaporation, freezing and membrane technology. Pulps, juices and extracts are the basic material used for preparation of various types of processed products. But due to their bulk and presence of large quantities of water they are difficult to store and transport. Concentration of juices, not only provides microbial stability, but also reduces the costs of packaging, transportation and storage by reducing the bulk of the material. Concentrated juice, contains far less water than normal, or “not-from-concentrate” forms of juice.

Plant genetic resources represent both the basis for agricultural development and a reservoir of genetic adaptability that acts as a buffer against environmental changes. The erosion of these resources threatens world food security. From an agricultural utilitarian standpoint, plant genetic resources can be considered limited and perishable natural resources. PGR forms a distinct group and include all plant species, which contribute to people livelihoods by providing food, medicine, feed for domestic animals, fibres, clothing, shelter, energy and other uses and are subject to cultivation by man as well as the wild relatives of these species. Genetic diversity simply means all the variety of genes that exist in a particular variety or species. They provide the raw material (genes) which, when used and combined in the right way, produce new and better plant varieties, and are an irreplaceable source of such characteristics as resistance to disease, local adaptation, and productivity. Plant genetic resources are now, and will continue to be in the future, of inestimable value independently of whether scientists use them by means of conventional plant breeding or modern genetic engineering. These genes are dispersed throughout local cultivars and natural plant populations that have been selected over thousands of years by farmers and nature for their characteristics of adaptation, resistance and/or productivity. The road to a continuous increase in the production and quality of food lies through the protection and efficient utilization of plant genetic resources; this requires their conservation, evaluation, documentation and exchange.

Introduction

National Gene Banks are now entering into an era of increased activity and responsibility, particularly for managing their own indigenous germplasm activities extending from collection to actual use of the genetic variation in crop improvement programmes. However, these tasks must be achieved with limited resources in best possible time frame. The core collection offers a potential opportunity to meet these challenges. Recognising that the sheer size of a germplasm collection could deter its use, Frankel (1984) proposed that it could be pruned to a ‘core collection’, which would represent, “with minimum repetitiveness, the genetic diversity of a crop species and its relatives”. The core collection consist of a limited set of accessions derived from a germplasm collection, chosen to represent the genetic spectrum in the whole collection, and including as much as possible of its genetic diversity (Brown, 1995). The remaining accessions would not necessarily be discarded but would be managed as a ‘reserve collection’. The proposal, the rationale, purposes and general principles of core collections have been critically examined (Brown, 1989 a and b). As to the size of a core collection, sampling theory of selective neutral alleles in finite populations indicate that about 10 % drawn randomly from the whole collection was relatively efficient in retaining its allelic variation (about 70 % retained). The core collection concept has attracted considerable discussion and debate in the past and has met criticism in many areas. Most of these concerns appear to arise from misuse or misunderstanding of the core approach and a number of core collections have been established during the past decade.

Food waste and loss is an enormous issue worldwide. The FAO states that ‘Hunger is still one of the most urgent development challenges, yet the world is producing more than enough food’, but a vast amount of what is produced gets lost on its way from the field to the consumer. According to the FAO, about 30% of cereals, 20% of dairy products, 35% of fish and seafood, 45% of fruits and vegetables, 20% of meat, 20% of oilseed and pulses and 45% of roots and tubers are lost or wasted. Postharvest food loss is defined as measurable qualitative and quantitative food loss along the supply chain, starting at the time of harvest till its consumption or other end uses. Food losses can either be the result of a direct quantitative loss, for example, during the process of harvest or transport or arise indirectly due to losses in crop quality such as undesired sprouting or water loss. Postharvest food loss consists of many factors, which have not changed much in the last 40 years and so postharvest food loss in general has not changed much. Figure 1 illustrates the main reasons for food loss along the supply chain and is based on ‘The food pipeline’ published by Bourne in 1977. Food loss is highest during storage due to pathogens (insects, bacteria and moulds), environmental conditions (e.g. rain, humidity, heat and frost), sprouting and quality loss (rancidity, water loss and saccharification) or animals (rodents and birds). Recently published data for Switzerland have shown that about 53%-55% of the initial fresh potato production and 41%-46% of the initial processing potato production are lost mostly due to pathogen infection, saccharification, water loss of tubers and early sprouting during storage (Buchholz et al, 2018).

Drought is one of the most frequent and widely spread stress factors that limit the production of vegetables in the world. Nearly every piece of cultivated land including those in the irrigated areas could be subjected to drought. However, the frequency, duration, severity, timing and extent of drought vary greatly from region to region.

The stress caused by deficit water in the living plant system, which is capable of inducing a potential injury, is called drought stress. Drought can also be defined as scarcity of water for plants and can be due to soil, atmospheric and physiological factors. In our conditions, the great damage to the production of vegetables is brought about by soil drought, which occurs when rapidly available water is spent from zone of the active rhizosphere. That particular moment represents the beginning of drought and as the water reserves in the soil become closer to the lower limit of optimum moisture, the drought becomes more intensive. Under such conditions, plants survive on the limited water available in the active rhizosphere and deeper soil layers, and this water is used to maintain essential life processes at the expense of crop yield.

The lack of precipitation causes drought; the area of cultivable soil in our country under irrigation is very small and so is the possibility to diminish the negative consequences of occasional shortage of precipitation. Aiming to reduce damage caused by drought, a huge number of research-experiments on drought, especially on tolerance has been conducted worldwide. Here, the attempts have been made to review the work done on drought tolerance by national and international centers.

Abstract

Dual inoculation of Rhizobium + VAM coupled with recommended NPK doses was found to produce the highest bean pod (6.38, 6.40 qha-1) and straw (35.11,35.35 qha-1) dry matter production and resulted in higher macro and micronutrient contents in bean leaves which were to the tune of 4.05, 4.06%N,0.44, 0.49 %P, 2.65, 2.66 %K, 2.65, 2.67%Ca, 64.67, 64.59 ppm Zn, 242, 242.2 ppm Fe, and 36, 36.33 ppm Mn. Under this treatment increase in bean pod and straw dry matter production during the years 2002 and 2003 was to the tune of 130, 131 and 81, 83 per cent, respectively over control.

Arecanut is an important traditional plantation crop of India and South-Eastern Asia. Also known as “betel nut”, the kernel is obtained from its fruit. It is mostly used by the people as masticatory and is an essential requisite during several religious, social and cultural functions of India. Arecanut has been widely used in East Africa, South-East Asia, and the Pacific Ocean islands, providing economic security for millions of people and for many sole means of livelihood in the Indian sub-continent. Arecanut is commercially cultivated in Bangladesh, China, India, Indonesia, Malaysia, Myanmar, Philippines, Sri Lanka, Thailand and Vietnam. Its current world production is 17.96 lakh tonnes from 12.26 lakh ha (FAO STAT, 2020).

Biodiversity is a matter of concern to everyone as most of the economic sectors depends on it e.g. agriculture depends on it for wild genetic resources and biological control, human health depends on nature for many pharmaceuticals, industry requires raw materials which come from the nature, tourism increasingly base its attraction on natural amenities linked to biodiversity, water resources require intact vegetation to protect watershed and prevent siltation, disaster prevention needs natural vegetation to help people to respond to drought and the lists goes on and on (Mc Neely, 2004). Each of these sectors needs to be reminded of its reliance on biodiversity and provided with opportunity to invest in insuring the continued survival of the biological basis of their prosperity. Thus biodiversity has emerged as an integral aspect of human life and hence undoubtedly one of the keystone of sustainable development. Biodiversity in arid lands are under severe threats due to habitat destruction (Manuder and Clubbe, 2002), invasion of species (O’Kennen et al., 1999) dilution of customary conservation practices, climate change (Given, 1994; WCMC, 1992), increasing human population, unsustainable exploitation of natural resources, grazing pressure etc.

India is floristically extremely rich with about 33 per cent of its botanical wealth (over 15,000 species of higher plants) being endemic. There are about 141 endemic genera distributed over 47 families (Nayar, 1980) the 4,900 endemic species, a large number are localised in the Himalayas (about 2,532 species), compared with the peninsular tract (1,788 species), and the Andaman and Nicobar Islands (185 species). Indian region is a major centre of domestication and diversity of crop plants (Zeven and de Wet, 1982; Arora, 1991). About 33 per cent of the cultivated plant species have theirorigin in this region (Damania, 2002). The Indian sub continent is a centre of domestication and diversification of several economically useful wild plant species comprising about 3,000 plants of edible value, 4,000 species having known reputed medicinal value, 700 plants of traditional and social significance, 500 fibre-yielding species, 400 fodder plants, 40 plants having insectivorous uses, 300 gum and dye yielding plants and 100 aromatic and essential oil-yielding species (Arora, 1991).

Biofertilizers can directly or indirectly influence the growth of plant. The direct influence can be through production of phytohormones or making the nutrients available to plants. The indirect effect can be through management of plant pathogens through biological control. Therefore, the purposeful introduction of biofertilizer inoculants to plant microbiome represents an environmentally sound option that holds a prominent position in order to reduce the dependency on agrochemicals (Adesemoye and Kloepper, 2009; Abhilash et al., 2016; Aloo, et al., 2019).

Microbes in soil can rarely exists as single cells and survive near the plant root canopy or in bulk soils or endophytes or even on plant surfaces (Lorito, 2006). The soil microflora occurs as complex members of microbiota (Hacquard, 2015). Microbial consortia (MC) are unique mixture of organisms which respond to the environment stress and adapt to stresses due to internal beneficial interactions among the microbial community. Ecosystem’s physiological functions by microflora is carried out by more than one microbial species with the functional diversity and succession among different microbial components. The microbial balance among the different microflora of a MC will consist of a continuous shift between actively growing cells and non-dividing cells of the microbial consortia. It has been reported that different microbial populations “talk” to each other by “quorum sensing” mechanism in a given environment by exchanging specific chemical signals (Thompson, 2015). Natural microbial consortia holds many specific properties like stability, functional diversity and perform complex functions. The natural consortia have generated an interest in manpulating synthetic consortia for the benefit of application (Minty, et al., 2013).

It has been well established that the biofertilizers are beneficial to plants and are cost-effective inputs for sustainable production system. However, there are some constraints with respect to its production, which are presented below:

10.1 Production constraints

10.1.1 Raw material

Eventhough there are large number of biofertilizer formulations, only few are considered as good carrier materials for biofertilizers such as peat and lignite. Moreover, its availability in India is limited and the quality is lacking for these carrier materials. Hence, a cost effective and locally available material with increased shelf-life is the need of the hour.

10.1.2 Specificity and availability of strains

As the microbial strains used as biofertilizers are specific to soil and agro-ecological conditions, availability of specific strains for the specific host and soil edaphic factors are inadequate.