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Sciarid(mushroom flies): Bradysia paupera, Lycoriella auripila: Sciaridae

The larvae feed on the mycelial attachments and restrict the growth of the spawn. The maggots also feed on the developing mushrooms or pinheads and thus cause loss in yield. They also bore the developing mushrooms and render them hollow.

Melons (Cucumis melo) are annuals with climbing, creeping or trailing vines of length up to three meters. The desert types quench thirst and add to the nutrient content of main diet. The non-desert types are used as vegetables. Muskmelon (Cucumis melo., 2n=2x=24) encompasses the netted, salmon -flesh cantaloupe, the smooth – skinned green fleshed ‘Honey Dew’, the wrinkled, white – fleshed, ‘Golden Beauty’ and several other dessert melons in USA.

Origin: Not known with certainty but, 40 or more wild species of Cucumis are found to occur in the tropics and subtropics of Africa. Wild species of Cucumis occur in Africa and it is likely that it originated in African continent. It does not appear to have been known to the ancient Egyptians, not to the Greeks and seemed to have reached Europe towards the decline of Roman Empire. Although melon was introduced into Asia at a comparatively later date there are undoubtedly well developed secondary centers of origin of C. melo in India, China and then Southern USSR. In India Oriental pickling melon (C. melo var conomon) and snap melon (C. melo var momordica) are unique and have considerable variability in Western Ghats of India. They are popular desert and preserving melons cultivated in Warm humid tropical condition of South India. It is also considered that China as primary center of origin and Indo-Burma as secondary center of origin. It has been introduced to Europe and from Europe to the USA by the early travelers. At present muskmelon is being cultivated throughout the world under tropical and subtropical climatic conditions. Polymorphism in leaf, flower, fruit shape and colour (Kirkbride, 1993), allowed the classification of horticulturally important melons into seven groups.

Melon or muskmelon (Cucumis melo L., 2n = 2x = 24, family Cucurbitaceae, mostly andromonoecious, cross-pollinated as well as self-pollinated) has latest global production close to 30 million tons where top ten producing countries are China (16.0 million tons), Turkey (1.8 million tons), Iran (1.6 million tons), Egypt (1.1 million tons), India (1.0 million tons), Kazakhstan (0.9 million tons), USA (0.8 million tons), Spain (0.7 million tons), Italy (0.6 million tons), Guatemala (0.6 million tons). India produced 1.2 million tons melons from 54000 ha acreage during 2017-18 giving a productivity of 22 tons/ha (MAFW, 2018).

US melons encompass the netted, salmon-flesh cantaloupe; the smooth-skinned green fleshed ‘Honey Dew’, the wrinkled-skinned, white-fleshed ‘Golden Beauty’ and several other dessert melons. Other forms with different fruit characters (white-fleshed, green-fleshed, having striped thin skin and juicy) are commonly found in India and in Orient as indigenous land-race cultivars. These are getting displaced by the cultivar types as cantaloupe, Madhuras and Galia due to their long shelf life.

Melon is mainly cultivated for the consumption of the fruits which can be harvested immature; in this case, the fruit is not sweet and can be eaten raw, cooked or pickled. In most cases, the fruit is harvested at maturity with high sugar content (mainly sucrose). Fruit is mainly eaten raw; marginal uses are cubes canned in syrup, in “fruits confits”, candies, ice-creams, biscuits and also in cosmetics. Locally, seeds can also be consumed (Pitrat, 2008).

Melons are annual plants that have up to three meters of climbing, creeping, or trailing vines. Several of them are consumed as dessert fruits while a few varieties/types are used for vegetable purposes. Generally, the fruits of commercial varieties are sweet, juicy, delicious with good nutritional and medicinal properties and a daily intake of 120-150 g can help in weight loss, better eye and skin health (Shivapriya et al., 2021).

Currently, muskmelon is being cultivated throughout the world, especially under tropical and subtropical climatic conditions. In India, muskmelon is grown in 54,000 ha with a production of 1.23 million tons (NHB, 2018). The estimated national seed requirement per year is about 27 tons with a value of about Rs. 27 crores. The crop is cultivated mainly in rabi season (November to February sowings), thus limiting its availability in the market during summer. Rarely, melons are cultivated for the off-season market, and those fetch a premium price. The total value of muskmelon fruits in the domestic market is estimated as Rs.1231 crores.

Muskmelon, Cucumis melo under the family Cucurbitaceae (Chromosome number: 2n = 2× = 24) is a highly relished crop because of its attractive flavour, sweet taste and refreshing effect. It is an important crop of Africa, Middle East, Asia, Southeast Asia, Japan, USA, South and Central America, France, Spain, Israel and many eastern European countries. Mature fruits are eaten fresh as a dessert fruit, canned or used for syrup or jam. Muskmelon is quite rich in ß carotene, vitamin B9, vitamin C and minerals like potassium and low in calorie content.
Origin, domestication and adaptation in India
The genus Cucumis, which includes cucumber (Cucumis sativus) and melon (Cucumis melo), has numerous wild African species, and it has therefore been assumed that melon originated in tropical Africa in eastern region, south of Sahara Desert. This proposition is supported by the presence of true wild melons which can still be found in some African countries. Some botanists consider melons native to the Levant and Egypt, while others place their origin in Iran, India, Afghanistan or Central Asia. Sebastian et al (2010) reported that the wild progenitor of C. melo occurs in India, and they confirmed that the Southeast Asian Cucumis hystrix is the closest relative of cucumber and most surprisingly, the closest relative of melon, Cucumis picrocarpus was from Australia. The wild forms of muskmelon reported from India are feral escapes derived from local cultivars.

The initial symptom of Alternaria brassiciola appears as small, dark colored spots which enlarge rapidly to form circular lesions. Under humid conditions a bluish velvety fungal growth is seen in the centre of these spots. Spots caused by Alternaria brassicae are almost similar to those produce by Alternaria brassicicola but are comparatively smaller and lighter in colour. When many spots are formed on the leaves, the leaves turn yellow and dry prematurely. Formation of pods and seeds are adversely affected.

Alternaria Blight
Diagnostic Symptoms
• Symptom first appear on the lower leaves as small circular brown necrotic spots which slowly increase in size.
• Many concentric spots coalesce to cover large patches showing blightening and defoliation in severe cases.
• Circular to linear, dark brown lesions also develop on stems and pods, which are elongated at later stage.
• Infected pods produce small, discolored and shriveled seeds( Fig.2).
Etiology
Scientific Classification
Kingdom : Fungi
Phylum : Ascomycota
Class : Dothideomycetes

Vegetables are cheaper source of carbohydrates, proteins, minerals, vitamins and dietary fibers, and hence, assume a place of very great importance in the diet of individuals. All kinds of vegetable are grown almost universally. India occupies the prime position in the production of vegetable crops and is the second largest producer of vegetables in the world. The area and production of vegetables in India have been increasing during the post-green revolution period, and the country is heading towards another revolution in the form of Golden Revolution. However, there is an utmost requirement for genetic improvement of vegetable crops in terms of productivity, qualitative characters and resistance to biotic and abiotic stresses. For any genetic improvement programme, the presence of genetic variation is pre-requisite and mutation is the ultimate source of this heritable variation.

Mutation technique that holds promise of generating a much wider desirable variability than classical breeding has been refined. Out of 2275 mutant varieties worldwide in all crops, as many as 66 mutants are in vegetables. In terms of percentage, China, India, USSR, The Netherlands, The United States of America and Japan account for 26.8, 11.5, 9.3, 7.8, 5.7 and 5.3%, respectively of mutagen varieties in all crops. Such varieties are 3% in case of vegetables. After mutation treatment by a mutagen to a specific plant, DNA alterations (deletion, duplication, inversion, translocation, or transposition of larger DNA fragments, or simple basic pair changes) occur and lead to the DNA sequence change. Hence, new characteristics of that plant are established. In fact, induced mutations supply us with many new plant lines, which may be used as primary materials for crop breeding. Hence, mutation breeding seems to be an effective and ultimate option to improve vegetable crops in the shortest possible time. A large number of new promising varieties in different crops, including vegetables, have successfully been developed worldwide using various mutagens (Chopra, 2005).

22.1 Introduction

Mutations are sudden heritable changes in the genotype of an organism. De Vries (1900) for the first time used the term mutation (mutare in Latin means ‘to change’) for the appearance of new types in evening primrose (Oenothera) plant. In 1901 he put forth the idea of producing mutations artificially for use in crop improvement. Alberto Pirovano (1922) was first to use X-rays and ultraviolet rays for inducing mutations in plants, but his work remained unknown. So, Muller (1927) became the first known to induce mutation in Drosophila fly using X-rays. Though Stadler (1928) had started working simultaneously on barley and maize and induced mutations, he was late in reporting mutation due to longer life cycle of these plants compared to Drosophila. Mutation may be gene mutation (the result of change in the nuclear gene or plasma gene) or chromosomal mutation (change in chromosome number, structure or chromosomal aberrations of various types).

Mutation is defined as a sudden heritable change in gene or in chromosome structure. The process of hereditary change is termed mutation and the individuals affected by the change are called mutants. Besides recombinations, mutations are the cause of genetic variation from which every breeding activity proceeds. By means of mutations, the multiplicity of the types of a population is not only increased by one genotype, but also by large number of further new genotypes due to possibility of subsequent recombinations of mutant with the existing genotypes.

Mutation breeding is a method that uses physical radiation or chemical means to induce genetic variation in plants to develop new crop varieties. Mutation can be defined as a sudden heritable change in the character of an organism which is not due to either segregation or recombination. Mutation is the source of most genetic variation and the motor of evolution. It is a natural process, which occurs spontaneously and slowly over generations in plants, animals and all living beings. It involves alteration of their DNA, leading to the development of changes within the organism. Mutation may be sped up through the treatment of physical or chemical mutagens to achieve alteration in characteristics that are useful for the development of new variety of a plant species.
Spontaneous mutations
Spontaneous mutations are the net result of all that can go wrong with DNA during the life cycle of an organism (Glickman et al., 1986). Thus, the types and amounts of spontaneous mutations produced are the resultant of all the cellular processes that are mutagenic and those that are anti-mutagenic. Spontaneous mutations occur naturally without any apparent cause however, there are two possible sources of origin of these mutations.

Sustainability refers to productive performance of a system over time. It implies use of natural resources to meet the present needs without jeopardizing the future potential. The Technical Advisory Committee of the Consultative Group of International Agricultural Research has defined sustainability as “Successful management of resources for agriculture to satisfy changing human needs while maintaining or enhancing the quality of the environment and conserving natural resources” (TAC, 1989). A sustainable system must be sustainable both ecologically and economically.

During the past several decades, production of horticultural crops has undergone a tremendous change in both developed and developing countries due to the development and use of fertilizers, pesticides, mechanization, soil fumigation, container production in soil-less media, breeding, micropropagation, pathogen elimination and a number of other innovations for attaining its future stability and sustainability. Recently, in modern horticulture, enhanced productivity depends heavily on inputs of fertilizers and pesticides to maintain an economic level of productivity. On the other hand, social and economic pressures are demanding that agricultural/horticultural practices, that have a damaging impact on the environment and pose risk to health of mankind, be curtailed. Thus throughout the world, agriculture including horticulture is at crossroads in terms of its future stability and sustainability. The solution for the above lies in developing new technology with reduced use of fertilizer and pesticides besides maintaining a sustainable level of productivity. The increased concern about the sustainability and undesirable side-effects of chemistry-based agriculture is prompting many researchers to more seriously evaluate alternative approaches. One such effort was put forth in the management of microbes that live in the rhizosphere soil around the roots of nearly all terrestrial plants. It has been believed that the main orchestrators of microbial activity in the rhizosphere are mycorrhizal fungi.

Mycotoxins are naturally occurring toxins produced by certain molds and can be found in food. The molds grow on a variety of different crops and foodstuffs including cereals, nuts, spices, dried fruits, apples and coffee beans, often under warm and humid conditions. Mycotoxins can cause a variety of adverse health effects and pose a serious health threat to both humans and livestock. The adverse health effects of mycotoxins range from acute poisoning to long-term effects such as immune deficiency and cancer. A scientific expert committee jointly convened by WHO and the Food and Agriculture Organization of the United Nations (FAO), called JECFA, is the international body responsible for evaluating the health risk from natural toxins including mycotoxins. International standards and codes of practice to limit exposure to mycotoxins from certain foods are established by the Codex Alimentarius Commission based on JECFA assessments.

Mycotoxins are toxic compounds that are naturally produced by certain types of molds (fungi). Molds that can produce mycotoxins grow on numerous foodstuffs such as cereals, dried fruits, nuts and spices. Mold growth can occur either before harvest or after harvest, during storage, on/in the food itself often under warm, damp and humid conditions. Most mycotoxins are chemically stable and survive food processing. Several hundred different mycotoxins have been identified, but the most commonly observed mycotoxins that present a concern to human health and livestock include aflatoxins, ochratoxin A, patulin, fumonisins, zearalenone and nivalenol/deoxynivalenol. Mycotoxins appear in the food chain as a result of mold infection of crops both before and after harvest. Exposure to mycotoxins can happen either directly by eating infected food or indirectly from animals that are fed contaminated feed, in particular from milk.

Introduction

Manipulating and controlling matter at the nanoscale, usually at dimensions less than 100 nanometers, is the focus of nanotechnology, also abbreviated as “nanotech,” a revolutionary branch of engineering and science. Particular material characteristics and behaviours, drastically different from their macroscopic equivalents, become apparent at this very microscopic size. With nanotechnology, we can design and build buildings, gadgets, and materials with hitherto unseen levels of control and accuracy.

Horticulture in the hills has special significance and specific requirements to sustain it for the improvement of the lot of the people living in the hills. The national policy on horticulture has to be so oriented so that it recognizes the varied agro climatic and soil conditions. The dynamic process of development and extension has to be specifically designed to cater to the requirements of the hill states; which, because of the difficult terrain, are by and large under-developed as compared to the rest of the country. The new national policy on horticulture should take into account the following points in order to make temperate horticulture a self sustaining enterprise.

Aims and Objectives

It has become evident that in order to achieve the food production targets of the future, a major effort will be required to enhance the seed replacement rates of various crops. This would require a major increase in the production of quality seeds, in which the private sector is expected to play a major role. At the same time, private and Public Sector Seed Organisations at both Central and State levels, will be expected to adopt economic pricing policies which would seek to realise the true cost of production. The creation of a facilitative climate for growth of a competitive and localised seed industry, encouragement of import of useful germplasm, and boosting of exports are core elements of the agricultural strategy of the new millennium.

Biotechnology will be a key factor in agricultural development in the coming decades. Genetic engineering/modification techniques hold enormous promise in developing crop varieties with a higher level of tolerance to biotic and abiotic stresses. A conducive atmosphere for application of frontier sciences in varietal development and for enhanced investments in research and development is a pressing requirement. At the same time, concerns relating to possible harm to human and animal health and bio-safety, as well as interests of farmers, must be addressed.

Globalization and economic liberalization have opened up new opportunities as well as challenges. The main objectives of the National Seeds Policy, therefore, are the provision of an appropriate climate for the seed industry to utilize available and prospective opportunities, safeguarding of the interests of Indian farmers and the conservation of agro-biodiversity. While unnecessary regulation needs to be dismantled, it must be ensured that gullible farmers are not exploited by unscrupulous elements. A regulatory system of a new genre is, therefore, needed, which will encompass quality assurance mechanisms coupled with facilitation of a vibrant and responsible seed industry.

1. INTRODUCTION

The Technology Protection System (TPS) or “Terminator Technology” as it has been called, allows plant breeders to genetically modify and protect their crop rights so they produce seed for one generation only. TPS was co-developed by the US Department of Agriculture (USDA) and Delta and Pine Land Company in 1998. They received U.S. Patent 5723765 entitled “Control of Plant Gene Expression”. The patent was based on research conducted under a Cooperative Research and Development Agreement (CRADA) between Delta and Pine Land Co. and the ARS USDA. The CRADA was signed in 1993.

Various methods are employed to dry flowers and foliage. The method adopted for drying depends largely on the character of the plant, that is to say whether the plant is glabrous, succulent or not succulent, hardy or delicate in nature. The suitable method for drying any given plant has to be studied elaborately. However, the different methods of drying are described broadly in this and consequent chapters.

The major drawback of dried arrangements and other dry flower products is that they are dull and lack the brightness of fresh flowers. To overcome this problem, flowers are bleached and dyed. This enhances the visual appeal of the product. Both chemical and natural dyes can be used. Squires (1971) reported on the use of various types of paints to colour dried foliage and flowers using brushes or by dipping and spraying. Enamel paints, interior paints, poster paints and tube paints could be employed for this purpose. Tampion and Reynolds (1971) explained the three ways by which dyeing can be carried out for fresh flowers. They are as follows:

Although the thriving dye industry in many countries throughout the world is now predominantly serviced by synthetic dyes, the knowledge of the plants used to produce natural dyes still survives among some dyers, who use plant dyes to some extent. Nonetheless this indigenous knowledge is rapidly being lost as increasingly less information is being passed on to succeeding generations. Thus several countries are taking steps to revitalize this natural dyes industry. In this article the history of natural dye plants is presented; several plants from selected countries, which are used in the dyeing process are documented, together with some general methods of dye production and fabric dyeing; pattern production and the chemical constituents of some of these plants. The potential for the sustainable utilization of this important ecofriendly renewable natural resource is discussed.