Preface The growing human population at an alarming rate is a major challenge facing agriculture in the 21st century. It is expected to rise to 9 billion or more during the mid of this century requiring food productivity to be doubled as compared to present, posing a great challenge on the part of the agricultural scientists to develop high yielding production technology and intensification in crop produce practices. Intensification would have serious implications of increased use of pesticides to control incidence of emerging pests for quick results. The increased use of pesticide would pose more problems in the form of development of insecticide resistant populations, resurgence of pest populations and pollution of the environment. These challenges have resulted in reorientation of pest management strategies in the form of ecofriendly approach of integrated pest management (IPM). The IPM has been widely practised and accepted in countries with temperate climates, however, such a progress has been inconspicuous by its absence in areas with tropical climates which constitute around two-third of earth's surface. The tropical areas have great diversity of land utilization and farming practices which have the potential of more ecological imbalances compared to temperate areas. Long activity periods in the absence of cold winter allows many insects to produce more number of overlapping generations. Furthermore, hot and wet conditions encountered in tropics affect the performance of pesticides and biology of the pests.

1.1 Introduction The human population is growing rapidly at an alarming rate, disproportionately to the production of food supplies, which will necessitate production of more food in the near future. The human population has already crossed the 7 billion mark and is expected to rise over 8-10 billion by 21st century. More than 800 million people are reported to suffer from malnutrition (Matson et al., 1997).  Thereby necessitating the need for more food production. Presently, agriculture faces the double challenge of feeding a fast growing population and at the same time prevents the degradation of the agricultural resource base. There appear to be two options for developing countries; either to improve agriculture through modernization, by emphasizing pesticides, fertilizers, machinery and modern varieties of crops; or use sustainable agriculture, promoting improved traditional, small-scale techniques (Pretty, 1999).

2.1    Introduction The hot and usually wet conditions in tropics adversely affect the performance of insecticides as well as biology of the pests. Pesticide usuage is declining throughout the world, but in tropics it is likely to increase threatening basic biological components of pest management, environment and safety of people.  Pest management in tropical agriculture is basically influenced by high diversity of organisms, diversity of physical features and ecosystems, moderate seasonal weather changes, and the human factor. The high biological diversity of the tropics includes a wide range of interacting organisms from which have been identified pests that affect health crops and livestock as well as cultural practices for pest management.  Physical features of the tropics are also diverse, and include high-altitude temperate zones, rain forests, savannah woodlands, grasslands, and desert zones. Each zone has its own biological diversity either existing in isolation or overlapping with others. Moderate seasonal weather changes in the tropics affect populations indirectly, through modification of interactions between organisms.

Introduction The tropics extends on  vast region of the earth surface ranging from 23½°C North to the Tropic of Cancer and 23½°C South to the Tropic of Capricorn. Several countries of Asia, Africa and Latin America include tropical areas. The tropical regions are the warmest area on the earth with average temperatures ranging between 20°C and 35°C. More than 80 % of the area in tropics supports forests and savannah and only 15% is under deserts, shrubs and grasses. About 5% of the area is under mid or high altitude with moderate climatic conditions. Evidently, the tropics support great diversity of physical and climatic conditions in different ecologies and different ecosystems. Temperature and daylight length is much higher throughout the year which induces more number of insect pests, their generations causing more damage in tropics. The increased menace of insect pests requires frequent and repeated use of chemical pesticide to mitigate the insect pest damage.

4.1 Introduction Insecticides, biocontrol agents and resistant varieties are the three important pest management tactics in vogue across the globe. Though several biocontrol agents have been recorded on major pests of economically important crops, mass multiplication techniques for most of them are yet to be perfected, and in several instances, the inundative releases of natural enemies are costlier than chemical insecticides. Moreover, unlike perennial crop ecosystems, the annual crop ecosystems like rice, cotton, sugarcane, pulses, etc. are frequently disturbed and hence, inoculative releases of biocontrol agents are often impractical. Above all, in spite of sustained effort from dedicated plant breeders across the globe, the resistant varieties with outstanding yield potential are very limited in numbers. Genetic engineering of crop plants though paved the way for introducing insecticidal genes more precisely and efficiently, the poorly understood ecological and sociological implications of genetically engineered crops in their target environment resist their strong footing in the pest management programmes in most of the crops especially of food crops. In this backdrop, insecticidal interference is inevitable to manage the insect pests, and they are the only weapon whenever the pest population crosses the economic threshold level.

5.1 Introduction Rainfed agriculture accounts for about 60-95% of farmed land in major areas of the world covering Saharan Africa, Latin America, North Africa and East Asia and South Asia. Agriculture in about 60 percent of 142 m ha of net cultivated area in India is rainfed without access to any source of irrigation. Rainfed agriculture is mostly practiced in arid, semi-arid and sub-humid regions where the rainfall is low in quantity, erratic in distribution and is also characterized by high inter-year variability. Together with poor and degraded soils, this limits the length of growing season as well as the choice of crops that can be grown sustainably. Coarse cereals, pulses, oilseeds and cotton dominate the cropping pattern in the regions where rainfed agriculture is concentrated. More importantly, these rainfed regions provide a livelihood to a majority of the rural poor, and as a result they are often described as concentrations of mass poverty and hotspots for civic strife. The productivity of crops grown in rainfed areas is considerably lower than its potential and much lower than that of irrigated crops. Enhancing the productivity of rainfed crops is therefore important from the viewpoints of growth, equity and sustainability.

6.1 Introduction The sensitivities of plants and of crop yield to a changing climate, is a major challenge for the agricultural research community to relate these findings to the broader societal concern with food security. This chapter reviews the direct effects of climate on both crop growth and yield and on plant pests and pathogens and the interactions that may occur between crops, pests, and pathogens under changed climate. The better understanding of the roles of pests and pathogens in crop production systems that might   make to enhanced food security is discussed. Evidence for the measured climate change on crops and their associated pests and pathogens is starting to be documented. Globally atmospheric CO2 has increased, and in northern latitudes mean temperature at many locations has increased by about 1.0–1.4 °C with accompanying changes in pest and pathogen incidence and to farming practices. Many pests and pathogens exhibit considerable capacity for generating, recombining, and selecting fit combinations of variants in key pathogenicity, fitness, and aggressiveness traits that there is little doubt that any new opportunities resulting from climate change will be exploited by them.

7.1 Introduction Sustainable agricultural systems must be adopted to increase the food production keeping in view of increase in human population. In tropical countries, insect pests are major challenges to increase food production by causing significant damage in the crop fields and stored grains and their products. Interventions by implementing timely integrated pest management strategies are necessary to reduce the yield losses. Efforts to control insect pests have predominantly relied on the use of broad-spectrum insecticides.  However, indiscriminate and irrational applications of insecticides have created the problems such as insecticide resistance, resurgence, secondary pest outbreak and the presence of residues in food and environment (Ansari et al., 2013). Globally, to reduce the pesticide dependence, various technologies have been developed using different approaches to monitor and maage insect pests which are discussed in this chapter.

8.1 Introduction Vegetables are cultivated over an area of about 19 million ha globally, with an annual production of 268 million tonnes; Asia and Africa account for more than 90% of the hectarage and production (FAO, 2011). Vegetable crops contribute to human and environmental health. Most vegetables can supply plant proteins, vitamins (especially vitamins A and C), folic acid, minerals such as iron and calcium, and dietary fiber to the human diet (Fowler, 2011). Vegetable legumes also fix atmospheric nitrogen in the soil, thus improving soil fertility. Their haulms can be used as high quality livestock fodder. Most vegetables are high-value, repeat-cycle crops that can help lift small-scale farmers out of poverty in developing tropical countries (Genova et al., 2010). However, vegetable production is often constrained by several severe biotic- and abiotic factors that reduce yields and profits.

9.1 Introduction Cereal crops are of global importance and the lifeline of the human civilization. The four most important cereals grown for human food in the tropics are rice, maize, sorghum and pearl millet. There are other minor cereals of tropical origin which are of local importance in the tropics. These include finger millet (Eleusine coracana), a staple food in parts of East and Central Africa; barnyard millet (Echinochloa frumentacea), cultivated in India and Southeast Asia; foxtail millet (Setaria italica), grown in parts of India; and teff (Eragrostis tef), which is confined to the Ethiopian highlands. The winter cereals wheat and barley are also grown to a limited extent in the tropics, largely at high altitudes: for example, wheat in Kenya and barley in Ethiopia. Wheat and barley are important crops in the Indian subcontinent, and are grown there in the cool season at low altitudes, but the bulk of the crop area lies outside the tropics.

10.1 Introduction Grain legumes such as chickpea, pigeonpea, cowpea, field pea , lentil, ,  and Phaseolus beans are the principal source of dietary protein among vegetarians, and are an integral part of daily diet in several forms worldwide. They are an important component of cropping systems to maintain soil fertility because of their ability to fix atmospheric nitrogen, extract water and nutrients from the deeper layers of the soil as compared to cereals, and add organic matter into the soil through leaf drop. However, grain legumes are mainly grown under rainfed conditions and the productivity levels are quite low mainly because of severe losses due to insect pests and diseases.  Average grain yield of pulses (0.86 t/ha) is only about one-fourth the average yields of cereals (3.54 t/ha).  Production and productivity of grain legumes is constrained by several biotic and abiotic factors, and suffer an average of 31.9 to 69.6% loss in crop productivity due to insects, diseases, drought, weeds,  and soil fertility. Pod borers (Helicoverpa and Maruca), Fusarium wilts, viral diseases, Ascochyta blight and Botrytis gray mold (Chen et al., 2011).

11.1 Introduction Tropical Root and Tuber Crops serve as primary or secondary staple to meet the calorie needs of one fifth of world’s population. These crops have myriad and complex roles to play in the food security and reduction of hunger and elimination of poverty. The starch content, pharmaceutical and nutraceutical value endow these crops with an extra ordinary range of potential and uses. Root and tuber crops are also greater sources of industrial raw materials for biodiesel and starch derived materials.

Introduction Banana (Musa sp; family: Musaceae) is the most popular commercial soft fruit crop grown in equatorial and subtropical regions of the world and also serves as a staple food since the dawn of recorded history in many countries (FAO, 2012). It has bounties of significance to the human beings and is one of the 4th most important food in the world after rice, wheat, and maize. Musa species grow in a wide range of environments ranging from the edible bananas and plantains of the tropics to cold hardy fiber and ornamental plants. They thrive well in an average annual temperature of 20°C and well distributed rainfall of 200 cm per year (Simmonds, 1959; Wardlaw, 1961). Banana is a large, perennial, monocotyledonous herb 2-9 m in height that arises from large, subterranean rhizomes called ‘corms’. Musa fruits are variable in size, shape, and color. They are generally elongate cylindrical, straight to strongly curved, 7-40 cm long, and 2-8 cm in diameter. The fruit apex is an important attributes in variety identification.

13.1 Introduction Citrus is one of the important fruit crops in India with the production of 111.47 lakh tons from 10.78 lakh hectares with the productivity of 10.34 tons/ha at national level as compared to 25-30 tons/ha in advanced citrus producing countries (NHB, 2013). The productivity and quality of citrus is severely affected by several factors; insect pests being one of them. More than 250 insect pests were reported to attack citrus in India. A total of  22 insect species  in Punjab (Atwal, 1976) ; 50  insect species  in  Karnataka;  42 insect species  in  North-Eastern Hilly region (Pathak and Rao, 1999);  20 insect species in West Bengal and  about a dozen  insect species  in central India have been reported on different citrus cultivars. Further, the pest occurrence and distribution in India indicated that about 21 species are common throughout the citrus growing areas and remaining species may occur in some areas either occasionally or rarely. Of the reported insect pests, Asian citrus psyllid (Diaphorina citri Kuwayama), citrus blackfly (Aleurocanthus woglumi Ashby), whitefly (Aleurolobus marlatti (Quaintance) and Dialeurodes sp.), leaf-miner (Phyllocnistis citrella Stainton), lemon butterfly (Papilio demoleus Linn.), leaf folder (Psorosticha zizyphi Stainton), aphids (Aphis spp. and Toxoptera spp.), thrips (Scirtothrips spp.), mealy bugs (Planococcus citri Risso), scales (Coccus hesperidus Linn), fruit sucking moth (Eudocima spp.), fruitfly (Bactrocera sp.), citrus trunk borer (Anoplophora versteegi Ritsema), bark eating caterpillar, lndarbela spp.

14.1 Introduction Sugarcane, basically a tropical crop in nature, requires a suitable high temperature, a lot of sunshine and rainfall ranging from 1250-2500 mm for its growth and yield. Relatively speaking, it is an intensive user of water as compared to rice and other crops. The total water requirement to mature the crop is about 64-80 acre inches.  Although globally but Brazil and Mexicos in Americas, India, Pakistan, Thailand and China in Asias, Australia and Africa, the Caribbean and to a smaller degree in southern Europe and the Middle East are major sugarcane growing areas in the World (Khan and Jamil, 1983). Historically famous for sugar, this crop has now attained a significant nadir for biofuel production (Mino, 2010). Sugarcane, a perennial grass, is exposed to all sorts of biotic and abiotic adversaries. The variation in weather parameters like sunlight, temperature, rainfall, humidity and solar radiation affect the different phases of growth like germination, tillering, cane formation and cane stalk elongation, as well as the maturity and ripening phases of plant (Malik, 2009).

15.1 Introduction In recent years, the role of plant secondary metabolites as protective constituents in the human diet has been a growing area of research. Unlike the traditional vitamins, they are not essential for short-term wellbeing, but there is increasing evidence that modest long-term intakes can have favourable impacts on the human health. Teas, coffee and cocoa represent plantation cash crops grown in many of the warmer, less developed regions of the world. They serve as stimulant beverages and their demand is ever increasing day by daily. However, production of these beverages is under the severe threat due to attack from various pests and diseases which cause considerable damage.

16.1 Introduction According to Howard (2001) the major world crop palms are coconut palm (Cocos nucifera L), African oil palm (Elaeis guineensis Jacq.) and date palms (Phoenix dactylifera L). Many other palm species provide products for international commerce and also grown as ornamentals. Some palm species are of local or regional importance and have great potential for expanded development and distribution. In general, commercial production of palms regularly starts on or near natural habitats with little agricultural development.

17.1 Introduction Cotton is a major fibre crop of global importance and has high commercial value. It is grown commercially in the temperate and tropical regions of more than 100 countries. Specific areas of production include countries such as China, USA, India, Pakistan, Uzbekistan, Turkey, Australia, Greece, Brazil, Egypt etc., where climatic conditions suit the natural growth requirements of cotton. These include periods of hot and dry weather and adequate moisture obtained through irrigation. Cotton crop is considered as one of the most important cash crops that influenced the industrial and agricultural economy of the different cotton growing countries of world. Thus, cotton is an immensely important crop for the sustainable economy of these countries and livelihood of the farming community. Cotton crop is considered as one of the most important cash crops that influenced the industrial and agricultural economy of the different cotton growing countries of world. Cotton cultivation and textile industry provide livelihood to million persons, therefore any failure of cotton crop significantly influence the economic growth of cotton belt and textile sector.

Plantation crops are high-value commercial crops of greater economic importance which play a pivotal role in the world economy. These include coconut, arecanut, tea, coffee, rubber, cocoa, oil palm, cashew. In this chapter only Cashew and Rubber are dealt with since the other plantation crops have been dealt in the earlier chapters.

19.1. Introduction A wave of research on insect pheromones has been initiated in early 1960’s in response to public concern and alarm about chemical pesticides to develop an elegant and ecologically safe technology for the control of insect pests. Pheromones, a class of semiochemicals are considered as ‘Biochemical Pesticides’, belong to the subdivision of Biorational pesticides which include “Microbials” (Viruses, Bacteria, Pathogens etc.) and “Biochemicals” (insect plant growth regulators, semiochemicals etc.). The term biorational (biological + rational) pesticides can be defined as the use of specific and selective chemicals, often with a unique modes of action, that are compatible with natural enemies and the environment, with minimal effect on non-target organisms. Biorational control is based on a diversity of chemical, biological and physical approaches for controlling insect pests which results in minimum risk to man and the environment (Horowitz  et al., 2009).

Chemical ecology is the study of ecological interactions between organisms mediated by chemical produced by those organisms. In short it is considered as the ecological functions of the chemicals. An insect, in various stages of its life history, performs various activities like host plant location, host plant selection,  feeding and oviposition, mating, escape from its natural enemies etc. and the chemicals play a crucial role than visual and audio signals. Chemical ecology encompasses the studies of these chemicals based interactions.

21.1 Introduction Plants and insects share a wonderful relationship. Both are dependent on each other at different levels and chemicals emitted by plants connect them to a large extent.  “Plants” contribute to a major share of occupancy on earth and makes several organisms such as insects & microbes and also humans to depend on them for their survival. This dependency leading to several interesting interactions between plants & insects which are often utilized by humans for their own benefit. Plants maintain incredible communication with their associated organisms. Since plants are rich banks of chemicals and constantly emit them in to its immediate environment which contributes in communication between insects and plants. Insects are the major organisms that have a long relation with the plants and there are several incredible ways how plants can interact with insect species.

22.1  Introduction Plant pests have been part of man’s environment for a long time. Traditional agriculture, which included diverse crops and indigenous crop management practices, provided little opportunity for pests to build up and spread rapidly (Smith and Allen, 1954). Crop production is constantly threatened by increasing difficulties in controlling insect pests, which are a major impediment to improved livelihoods of poor farmers. However, in the quest to increase food production for the growing population, use of pesticides became a norm in crop management. Pesticides became an integral part of the process owing to losses from weeds, diseases and pests reducing the harvestable produce. Use of pesticides along with high yielding varieties, irrigation and improved seed did result in increased productivity. But the rampant use of these chemicals, under the adage, ‘if little is good, a lot more will be better’ has played havoc with human and other life forms.

23.1 Introduction Cultural methods have been in practice for pest management in traditional systems of agriculture since time immemorial. The worldwide awareness of safe environment provided the impetus to foster non-chemical pest management strategies. Of these strategies, cultural control constitutes the most farmer-oriented approach, where the weak points in the biology and behaviour of insects are exploited and pressure is exerted on the population by manipulating the environment.  In addition to the cultural practices, the other widely used approach is the use of physical control methods which hold promise and provide an attractive alternative to current practices, particularly when integrated into a general control scheme incorporating cultural methods, plant breeding, biological or behavioural methods and pesticides. In physical control methods, the physical environment of the pest is modified in such a way that the insects no longer pose a threat to the agricultural crop.

24.1 Introduction Taxonomy, which includes identification and classification has transformed into systematics and biosystematics in the recent times and is integrating itself into the biodiversity, which is now a global phenomenon occupying the main thrust of human life (Narendran, 2001). The magnitude and cause of this biodiversity is the central problem of taxonomy and one of the key problems of science as a whole, not to speak of pest management. The science of taxonomy started in the late eighteenth century by a Swedish biologist, Carl Linnaeus who with a small number of similar minded scientists pioneered a standard system of using two Latin names for an organism, denoting “genus” and “species” which is still in vogue. This led to referring of biological organisms by an universally agreed name and identity, and further providing means for their realistic classifications. When these identifications and classifications got strengthened further with accumulated biological knowledge, it allowed the development of modern biology on a sustainable and stable base.

Like other sciences, the insect–pest management research is also based on scientific methods requires formulation of hypothesis from observed facts through logical arguments which in turn, verified through objective methods. For instance, in integrated pest management the entomologists are primarily concerned with the estimation of insect-pest population, its distribution pattern over time and space, its relationship and fluctuation in population with the effect of weather parameters and ultimately its control measure through the judicious use of chemicals, biological control agents and resistant varieties etc. Two major practical aspects of scientific investigation are as      ·    collection of data and      ·    interpretation of the collected data.

26.1 Introduction The green revolution brought dramatic changes in productivity of rice and wheat and the production increased tremendously using high yielding wheat and rice varieties coupled with fertilizers and pesticide use to meet urgent demands of food. The world population is growing rapidly at an alarming rate. It has crossed 7 billion mark and is expected to become between 8.3 and 10.9 billion by 2050 (United States Census Bureau (USCB). India is second largest populous country of the world with 17.4 % of world population. Such an enormous overpopulation will result in extreme pressure on environment, global food supplies and energy resources. The less arable land and fewer renewable and non-renewable resources, the food production has to come from increases in production rather than expansion of cultivable areas.