Preface   India is an agricultural country and its major population and economy too are dependent directly or indirectly on agriculture and related activities. In the efforts to increase the food production and make the country self sufficient in food grains, modern technology adopted since ‘Green Revolution’ in the middle sixties has paid a significant role, in this, the contribution of pesticides was more in addition to fertilizers, irrigation, genotypes and seeds. Plant protection is an integral part of the crop protection and pesticides proved to be valuable means in plant protection to ensure plenty food. However, the synthetic pesticides posed risk to human safety and health and also environmental pollution. Furthermore, repeated and heavy applications of pesticides add to the cost of production and misery to farmers. The reflected adverse effects of pesticides enforced the scientists and chemists throughout world to search for safer pesticides. Throughout history, plant products have been successfully exploited as insecticides, repellents and antifeedents. The number of options in discovery and development of natural plant products as pest controlling agents is larger than for synthetic pesticides. The search and use of safer plant derived products called botanicals are increasing now as a viable component of Integrated Pest Management (IPM) concept. The future pest management programmes for sustainable agriculture and public health emphasizes on plant extracts called botanicals and isolated potent plant products and their derivatives in addition to safer synthetic pesticides. The usage of plant products is being encouraged all over the world. Many old practices of pest control are being reconsidered and one of them, the most common is isolation of certain chemicals and preparation of extracts that can be used effectively. Fortunately, India is rich with verities of herbal plants, vast sea wealth, strong cultural heritage and traditional practices. The natural products will be the effective pest management tactics in future. However, a strong will and concrete efforts are required to exploit the pest management efficacy of the natural products.

India is an agricultural country and nearly 70% of its population is dependent directly or indirectly on agriculture and related activities. At present, about 173 million hectares of land is under agriculture of which about 143 million hectare are cultivated without fallow. Mounting pressures of teeming population and shrinking land (due to urbanization) have necessitated the production of increasingly more food per unit area. In the efforts to increase the food production and make the country self-sufficient in food grains, modern technology adopted since ‘Green Revolution’ in the middle sixties has paid a significant role. Higher yields in almost all crops were possible with exotic and high yielding genotypes and availability of seeds, heavy doses of fertilizers, frequent irrigation, labour and repeated applications of pesticides. However, several genotypes particularly hybrids proved to be susceptible to pests and disease pathogens. Insect-pests, diseases and weeds are important biotic-constraints inflicting 20-25% losses in agricultural production. Farmers were therefore compelled to use pesticides extensively and frequently. Plant protection is an integral part of the crop production and pesticides proved to be valuable means in plant protection to ensure plenty food. However, some of the pesticides are highly hazardous and their residue remains undetected and posses risk to human safety and health. Moreover, the repeated and incorrect applications without following need-based criteria have resulted in several secondary side effects 2. For instance, increased resistance of pests to insecticides, harmful to beneficial and non-target insects and animals, undesirable effects on crop plants and environmental hazards. Safety has become a major worry in factories and outside the working places. Besides these, repeated and heavy pesticide applications add to the cost of production and misery to farmer. These ill effects of synthetic pesticides have aroused interest in alternate methods of plant protection.

Introduction In agriculture and public health sectors, a variety of pesticides are still in uses that are toxic chemicals and having broad-spectrum actions. They kill target species but also harm the ecosystem seriously by affecting desirable organisms, thus, badly impairing prey-predator relationship. Most of these pesticides are persistent or non-biodegradable and hence exhibit biological magnification by accumulating at higher concentration in the organism, which are on the top of the food chain. The other drawbacks of repeated use of pesticides are eradication of natural enemies of pests, increased level of pesticide residues in soil, water, food and fodder crops, resistance of pests to pesticides and resurgence of minor pests in addition to the environmental pollution. It is clear that once used pesticide may persist, somewhere causing serious harm to the mankind and his ecosystem. The increasing incidence of pesticide harms is fueling the need for new pesticides, which are toxicologically safe, more selective and efficacious and environment-friendly. Now the natural compounds, thus, have increasingly become the focus of those interested in discovery of pesticides. Tens of thousands of secondary products of plants have been identified and there are estimates that hundreds of thousands of these compounds exist. There is growing evidence that most of these compounds are involved in the interaction of plants with other species-primarily the defense of the plants from plant pests. Thus, these secondary compounds represent a large reservoir of chemical structures with biological activity. This resource is largely untapped for use as pest management agents3, 4. The extraction of such chemicals from plants and derivatives of potent compounds are being encouraged all over the world under the Integrated Pest Management (IPM) approaches. The natural compounds and their synthetic derivatives are more selective in action, completely biodegradable and environment-friendly. In short, natural ways of pests control have already been established and are receiving much attention these days.

Introduction In man’s continued effort to enhance food production, new high yielding crop varieties and new techniques for crop and field management are being constantly evolved resulting in a parallel increase in disease occurrence which calls for their efficient management. Of the various management strategies available for disease management, the chemical strategies have so far dominated our thinking. Over emphasis on chemical control of plant diseases has caused serious imbalances in the agro-ecosystem1-2. The shift to exploration of non-chemical strategies is likely to correct the imbalance in our approach and subsequently improve the understanding of Integrated Disease Management (IDM). IDM is defined as ‘a disease management system that utilizes all suitable techniques in a compatible manner to reduce and maintain pest pathogen population at levels below those causing economic injury.’ Fungi are the important group of pathogens. In continuation of our work on natural pest management agents the present investigation aims at the preparation of different types of aqueous extracts of locally available four Indian medicinal plants viz., Datura stramonium Linn (Datura), Ricinus communis Linn. (Castor), Vitex trifolia Linn. (Nirgudi) and Nerium indicum Mill. (Kanher); study of stability of these extracts at room temperature; and evaluation of their anti-fungal potencies. This study will help to preserve and increase the pest management potency and efficacy of natural products.

Introduction The biological systems on the earth are in a dynamic equilibrium. In this attempt to live comfortably man disturbs this equilibrium in many, one of which is the cultivation of crop plants to meet his requirements for food, clothing and shelter. Intensive and extensive n of crop plants provides not only better crops but also better ties for pests and diseases to attack these crops. The greater loss due to the pests and diseases, the greater the attempt to these damages. Bacteria are one of the important disease since time immemorial. Bacteria are found in every ble habitat. They are unicellular, but display a variety of ‘cal forms. The present investigation on the botanicals  has been aimed at preparation of different types of aqueous extracts of locally available medicinal plants viz., Datura stramonium (Datura), Ricinus Castor), Vitex trifolia (Nirgudi) and Nerium indicum (Kanher); the study concentration and stability of these extracts at room temperature; and evaluation of their anti-bacterial activities. This study will be helpful to preserve and increase the pest management potency and efficiency of plant derived products.

Introduction There are a number of estimates of post-harvest losses. The most conservative estimates for the handling losses at about 10 per cent, a quantity good enough to feed at least 60 million people. Storage loss occurs due to quantitative and qualitative damages caused by insects, mites, fungi, rodents, birds, heat, moisture, etc. Several hundred insect species have been reported to be associated with stored grains and milled and processed foods, but some 50 of these species are considered injurious. Under Indian conditions, the most important insect pests of stored grains are Sitophilus oryzae (Rice weevil), Tribolium castaneum (Red flour beetle), Rhizopertha dominica (Lesser grain borer), Callasobruchus spp. (Pulse beetle), etc. The use of repellents to ward off insects has been a very old practice of mankind. The simple fly swatters, feather dusters, hand fans, mosquito nets etc., are some of the physical repellants still in use. In our own country, mustard oil or turmeric (haldi) water is also used as a mosquito repellent. Fire and smoke are the two oldest insect repellents known to man. To get rid of wasp nests from our dwelling or ward off honeybees during honey extraction, smoke is normally employed. Similarly sandal dhoop is often burnt to purify air (i. e. to ward off insects) in our houses. Chemicals that prevent insect damage to plants or animals by rendering them unattractive or offensive are called repellents. A more broad-based definition would be: non-poisonous or mildly poisonous chemicals that induce avoiding (oriented movements in insects away from their source. Repellents are more important in the protection of man and his animals from insect attacks than in the protection plants.

Introduction The food problem in the world is expected to become more serious if the world population keeps growing at the present rate. Out of various strategies to solve the problem, the post-harvest handling of the grains is of paramount importance. Tribolium species is major pest of stored grain and grain products in the tropics. Control of this insect relies heavily on the use of synthetic insecticides, which has led to many problems such as increasing costs of application, pest resurgence, pest resistance to pesticides and lethal effects on non-target organisms in addition to direct toxicity to users and disturbances of the environment. Thus, insecticides of natural origin are rational alternatives of synthetic insecticides. Several botanicals, natural products and their derivatives have been reported and exhibit better efficacy and potency against the stored grain pests. In the present investigation, an attempt has also made to test ovicidal, larvicidal and adult emergence suppression potentials of the extracts of some of the locally available Indian medicinal plant viz., Datura stramonium, Ricinus communis, Vitex trifolia and Nerium indicum against T. castaneum against T. castaneum, commonly called as Red flour beetle.

Since the wide introduction of organochlorines and other synthetics in early 50’s farmers have heavily relied on the chemical pesticides for pest control. Over emphasis on chemical control has caused serious imbalances in the agro-ecosystem. The enormous quantities of chemicals, poisonous to microbial life, that fall on earth gets mixed up well with soil. Some problems like non-target effects of chemicals as well as latrogenic diseases are being experienced. Coupled with these, the increasing awareness of impeding pollution, health hazards and development of resistance have intensified the search for alternative strategies. In the present investigation, the attempts have been made to test the stability and pest management efficacy of the plant extracts of some Indian medicinal plants, namely, Datura stramonium, Ricinus communis, Vitex trifolia and Nerium indicum. In the earlier chapters detailed methodologies and the results have been elaborated. This chapter embodes the comprehensive inter- and intra-comparative results and discussion on the basis of selected plants, extraction media, pest species and bioassay followed by conclusions. The hot sterilized water extracts of R. communis were found to be more stable (i.e. 20 days to start the fermentation). In overall study the plant extracts were stable or viable means active for three to four weeks only. In most cases, the activity of cold and hot water extracts was found to be increasing with fermentation however the decrease in the activity of some extract was also observed. The highest mean anti-fungal activity was reported for R. communis extracts followed by D. stramonium and N. indicum aqueous extracts, whereas no any anti-fungal potency was reflected by V. trifolia against test fungi species. R. communis and N. indicum extracts, the cold water method extraction showed greater positive effects in terms of mean anti-fungal potency as compared to the hot water extracts. The water extraction of D. stramonium was found to be more effective in anti-fungal activity study.