eChapters

Race: A subspecific category that is based on particular attributes, such as behavioral or physiological (other than morphological) differences; similar to a subspecies; often used in describing plant pathogens.

Race: Subspecies (q.v.).

Race: A naturally occurring group within a species usually visually indistinguishable but with some physiological difference from other members of the species, e.g., with a different plant host range. cf. strain.

Radial cell: A cell bordered anteriorly by a branch of the radius; the marginal cell (Hymenoptera).

Radial cross vein: A cross vein connecting R₁ and the branch of the radius immediately behind it.

Radial sector: The posterior of the two main branches of the radius.

Radiation: See Adaptive radiation.

Substantial onion losses occur after harvest through sprouting, rotting, physiological weight reduction and quality deterioration. Proper harvest timing, careful handling and effective curing are therefore essential for maintaining marketability and extending storage life. This chapter explains maturity indices, including appropriate levels of top fall, and compares field curing with forced-air methods. It examines topping, grading, packaging, transportation, storage temperature, relative humidity, ventilation and disease management. Physiological and biochemical changes occurring during storage are also considered. An integrated post-harvest approach combining correct maturity assessment, suitable harvesting, complete curing, careful handling, controlled storage and regular quality monitoring can considerably reduce losses and improve year-round onion availability.

Protected Cultivation

Protected cultivation (PC) may be defined as the “modification of the natural environment to achieve optimum plant growth” (Singh, 2005). Modifications can be made to both the aerial and root environments to increase crop yields, extend the growing season and permit plant growth during periods of the year not commonly used to grow open field crops. PC may also indicate comprehensive systems of ‘Controlled Environmental Agriculture’ in which all the aspects of natural environment are modified for maximum plant growth and economic return.

Pollination is one of the most essential ecosystem services which is effectual for crop productivity, biodiversity and human livelihood. Pollination is the process of transferring pollens from anther to stigma for plant reproduction and has direct impact on crop productivity. Conservation and management of pollinators is still ignored in the agriculture development program by the policy makers. In agricultural ecosystem, many agricultural crops are dependent on insects for their pollination, and assisted pollination may have to be done when natural pollination is insufficient in order to reduce potential yield loss (Klein et al., 2007). About 80% of the world’s flowering plant species are dedicated to animal pollination, mostly by insects (FAO, 2007). In 2005, globally, pollinators’ pollination services economic value was estimated to be about €153 billion (Gallai et al., 2009). The United Nations also reported that the economics of ecosystems and biodiversity by insect pollination was valued at £134 billion.

Agricultural biodiversity is known as crop genetic resources, although agroecosystems hold a wide diversity of other organisms that contribute toward their productivity and sustainability. Amongst these pollinators play the massive role in crop pollination and thus ensure that fruit or seeds are formed. Over 3 decades ago, the international community began to emphasize on the importance of pollinators. In agro-ecosystems, pollinators are essential for agriculture, horticultural and forage production as well as the production of seed for many root and fiber crops. Pollinators such as bees, birds and bats affect 35 per cent of the world’s crop production, increasing outputs of 87 of the leading food crops worldwide, plus many plant-derived medicines in our pharmacies (Klein et al., 2007). Food security, food diversity, human nutrition and plant diversity all rely strongly on animal pollinators. Pollination is an essential ecosystem service that enables plant reproduction and food production. The pollinators’ abundance and diversity play pivotal role for enhancement of the productivity, quality and maintenance of natural resources of plant biodiversity. The diminution of pollination abundance and their diversity certainly affect productivity, quality and plant biodiversity.

Insects are prevalent on this globe due to their varied adaptations and hence constitute the largest component of the animal kingdom. Only around 5 per cent of the total insect species, act as pests, rest either are beneficial like honey bees, lac insect, silk worms etc. or are harmless. Insect pests can be of medical, veterinary, house hold and agricultural importance, as these creatures harm our health, animals’ health, our belongings and also the agricultural health. Though all these components are equally important but, in this book, the last one i.e. agricultural health, have been taken into consideration. Insect pests cause around 20 per cent loss to our crops by directly or indirectly affecting the crops both quantitatively and qualitatively. The insects have different types of mouth parts which are used for sucking, biting and chewing, sponging and lapping, siphoning etc. for food required for their survival and the insects with sucking and biting, and chewing types of mouth parts cause much of the damage. The mites (Phylum Arthropoda) though do not belong to class Insecta but in some instances also are of economic importance as they cause economic damage to agricultural crops and produce.

Pollinators are organisms that help to transfer pollen from anther to stigma of the same species for fertilization and thereby produce seeds and fruits. Pollinators belong to diverse groups viz. insects, birds, reptiles, mammals, etc. Insects; bees butterflies, moths, wasps, flies, some types of beetles. Out of insect pollinators, bees are most important pollinator. Insect pollinators are critical to the production of many crops and play pivotal role to maintain the biodiversity. The decline in honeybee and other pollinator populations have more attention of scientific and public concern globally as well as in India. A number of factors have been observed as potential contributors to these declines and no single factor has been identified as the cause. The available science suggests that multiple factors responsible for population depletion and extinction, including loss of habitat and food sources, diseases, viruses, pests, and pesticide exposure. It is also known that certain pesticides can pose an immediate or “acute” threat to the insect pollinators and bees. In order to protect pollinators, the labels of pesticides that pose such risks should specify detailed directions of application to reduce potential exposure.

Introduction

The goals and ideas of organic farming and regenerative agriculture are quite similar. Organic farming is a method of cultivating crops that prioritizes ecological sustainability by eschewing the use of artificial chemicals and genetically modified organisms in favor of more traditional practices. Producing residue- free food while also improving soil health, biodiversity, and ecological balance is the primary goal of this method. To restore and improve the health of the soil, ecosystems, and communities involved in agricultural systems, regenerative agriculture goes above and beyond organic farming. The ultimate goal is the development of resilient and sustainable agricultural systems that can deal with the effects of climate change.

Regenerative agriculture and organic farming share a common set of values, including an emphasis on the importance of good soils to successful and sustainable farming. Crop rotation, cover crops, and composting are some of the methods advocated by these people to improve soil fertility, structure, and biological activity. Preservation and promotion of a wide variety of plant and animal life on and around farms is an aim of both organic and regenerative farming practices. Pest and disease management, pollination, and ecosystem stability are all bolstered by biodiversity. Both methods encourage using less or no man- made chemicals, such as those found in pesticides, herbicides, and fertilizers. Organic matter, compost, and biological pest management are just some of the natural inputs that these farmers rely on. Water, energy, and material resource conservation are fundamental to both organic farming and regenerative agriculture. To lessen agriculture’s impact on the environment, they advocate for methods including water management, efficient irrigation systems, and the use of renewable energy. Strong relationships and collaborations between farmers, customers, and local communities are prioritized by these methods. All along the agricultural supply chain, they are committed to fair trade, social equity, and transparency. Farmers may grow healthy, resilient, and sustainable farming systems by applying the holistic concepts of regenerative agriculture to conventional organic farming practices. In addition to strengthening the bond between agriculture and its natural surroundings, these methods also improve soil quality, lessen negative effects on the environment, increase biodiversity, and result in more nutritionally dense food.

Introduction

The growing interest in agricultural production over the past few decades has resulted in more farming systems that rely on chemical pesticides or chemical fertilizers, which has seriously harmed the soil, water, air, and climate while paying little attention to quality or concern for the agricultural system’s negative effects on ecosystems. But as time went on, scientific research began to focus on sustainable agriculture, organic farming, clean agriculture, and other ideas that eventually evolved into agricultural systems that maintain the balance in all areas of the agricultural and production process, as well as consumer and environmental concerns. These agricultural approaches have attracted the attention of numerous farmers, and many large farms are now interested in organic farming in the context of sustainable agriculture. The idea of sustainable agriculture is simply the production of food, fiber, other plant products, or even animal products using agricultural techniques that protect the environment, public health, and human societies from the detrimental effects arising from carrying out that process using the standard format as well as technology that also takes into account animal welfare, such that this type of agriculture will enable us to produce healthy foods without compromise (Bahlai et al., 2010; Muller et al., 2017, and Palmgren et al., 2015).

The Future of Sustainable Agriculture

The adoption of sustainable agriculture was made to raise awareness of their significance and to support the governments of plantations and businesses that operate within the parameters of sustainability, in particular organic agriculture, which is clean and recently devoted a lot of studies and research as well as major scientific conferences on sustainable agriculture, as were a lot of major exhibitions for organic goods and food made from organic ingredients around the world. Specifically, the potential role that organic agriculture could play in reducing the adverse effects of climate change, reducing deforestation rates, maintaining biological risk, and also arranging the steady increase in the world’s population, attracted attention to the level of international policy.

Introduction

According to research released not too long ago by the United Nations, the population of the entire planet is expected to reach around 8 billion by the end of the year 2022. As a consequence, the future demand for the production and distribution of food must be satisfied to provide sustenance for the expanding population of the world and to alleviate human suffering. However, in countries like India, food is wasted at an alarmingly high rate every year because there are insufficient facilities for cooling and storing food once it has been harvested. The majority of the losses began on the farm level since the fresh produce, which requires fast refrigeration after harvest in large quantities, was unable to be given, which led to the spoilage of the food. It is especially vital to shorten the amount of time between harvesting and first cooling to slow down the rate at which newly harvested fruits and vegetables breathe out carbon dioxide and exhale it. When keeping fresh fruits and vegetables, the two most important controlling parameters are temperature and relative humidity. These two factors work together to minimize the amount of water that is lost and to keep the product quality from deteriorating. Following their preferred ranges of temperature and relative humidity, fruits and vegetables can be divided into the following categories: (Table 15.1). For the objectives of on-farm cooling, the majority of fresh fruits and vegetables that are classified as belonging to groups 1 and 2 need to be concentrated, which necessitates maintaining an ideal temperature of less than 10°C and a relative humidity of more than 90%.

1. Detection means the existence of whatever do you want detecting but diagnosis is that the analysis in depth of existing thing.
2. Objectively look for, listen to the credible complains, symptoms that is sometimes not visible at all.
3. It is art or skill of identifying some abnormalities, i.e. which is below or higher than the normal permissible range/threshold.

Weeds pose serious problems to agriculture and environment. Weeds are plants that are undesirable to human activity at a particular time and place, and therefore, weeds will always be associated with human endeavours. In agriculture these not only cause huge reductions in crop yields but also increase cost of cultivation, reduce input efficiency, interfere with agricultural operations, impair quality, act as alternate hosts for several insect pests, diseases and nematodes. In non-crop areas, they affect aesthetic look of the ecosystem as well as native biodiversity and health and quality of life. Weeds are a big constraint in crop production and are responsible for heavy yield losses in almost all the crops. “Being fore-warned is fore-armed” is the principle behind preparation of perspective plans. Weeds are big constraints in crop production and are responsible for heavy yield losses in all crops. Out of the losses due to various biotic stresses, weeds are known to account for nearly one third. Proper management of weeds is essential to meet the growing demand of foodgrains, pulses, oilseeds and other crops by the ever increasing population. As per the projections of IFPRI, Washington there is a likelihood of shortfall of 41 per cent in the food grain production in the country by 2020.

Fungi include a large group of organisms and there are about 72,000 described species and the total number of species in the world may be as high as 1.5 million (Hawksworth et al., 1995). The infections that these fungi cause on a group of organisms viz. plants, animals, insects etc. may or may not be beneficial depending upon the type of host infected. With reference to insects, fungal infections in pest insects are beneficial which can be used effectively in biocontrol programmes. On the other hand, fungal infections in beneficial insects are harmful.

The entomopathogenic or entomogenous fungi mainly include those genera of fungi that associate with insects and some arthropods in a variety of ways. The association with the insects may be saprophytic, commensalistic, parasitic or pathogenic with the insect host. Some entomopathogenic fungi like Coelomomyces are obligate pathogens which can’t be cultured outside a living host, but most of them are however, facultative pathogens capable of growing without host insect. More than 750 spp of fungi, mostly deuteromyctes and entomophthorales from about 100 genera are pathogenic on insects and many of them offer great potential for pest management. The entomopathogenic fungi which have been most intensively investigated include Beauveria, Metarrhizum, Paecilomyces, Entomophthora, Verticillium, Hirsutella, Eryina, Mefarrhizium etc. Out of them Beauveria and Mefarrhizium have been extensively used in large scale for the control of several crop pests.

Insect collection is a source of recreation for many people and maybe a hobby for those who are interested in studying insects. Methods of collection and preservation of insects are the pre-requisite to studying the insects and their various internal and external organs. After collection, it becomes imperative to keep and preserve the insect specimens intact and safe for a longer time to further study the characters or to develop the insect collection museum. Let‘s have a look and do the different types methods of collection, and devices used for the collection and preservation of insects including immature stages in this practical session.

Collection

 The purposes of insect collection are:

To know the occurrence of a particular insect in a particular locality.

Taxonomic study of insects.

Identification of insects.

To study the bionomics and rearing of insects for various entomological experiments.

To develop the insect repository etc.

INTRODUCTION

The first significant economic contribution of host plant resistance in agriculture was made in 1890 when European grape vines were successfully grafted on resistant root stock to save the French Wine industry from viteus vilifaliac (Fitch). Studies from the past century have led to the development of resistant varieties in about 15 crops to about 50 key insect pests. During the last 20 years alone, more than 500 insect resistant cultivars of rice, maize, cotton, sorghum, alfalfa and wheat have been developed and released world wide (Dhaliwal and Arora, 2001). The insect resistant varieties are grown on millions of ha. annually and help the farmers to save billions of dollars in insecticide costs (Dhaliwal and Arora, 2001). The role of Host Plant Resistance in Integrated Pest Management is discussed below.

Introduction

Advent of agriculture in India dates back to around 2000 BC, the period of Indus Valley Civilization. South and East Asia also witnessed the start of agriculture around the same time. The crops were grown only during the monsoons. Winters served as a closed period for crops as well as for the pests. Even at that time a number of insect pests were known to cause serious damage to different crops. Agriculture has been revolutionized during the few decades since World War II (Kupatt et al., 2005). Introduction of high yielding varieties and associated technology resulted in tremendous increase in the production from the same piece of land. The results of these changes include a dramatic reduction in time and resources needed to provide an unprecedented quantity of quality food and fiber. The initial introduction of plant protection agents as wonder material did not lasted long, as very soon their ill effects on human health and environment were witnessed.

INTRODUCTION
 
In India tremendous progress has been made in agriculture. In absence of check on population growth, it may cross 1.5 billions by 2030. As a consequence per capita availability of land 0.13 ha will further reduce to 0.1 hectare in 2020 A.D. The demand of growing population for food and fibre require country to produce higher yields from presently cultivated land. Currently an average of 2790 calories of food available each day for every human on the planet, (23 per cent more than in 1961 and enough to feed every one). The production targets and required yield to feed the ever increasing current population with present available resources will require the growth rate of 2.35 and 2.2 per cent in rice and wheat, respectively and as high as 4.45 and 3.38 per cent for pulses and oil seeds, respectively. This requires national average yield to be increased by 30-50 per cent, which is not a cakewalk. India will require producing additional 5-6 million tones annually to keep pace with ever-increasing national food and nutritional requirements. Recurrent famines, starvation death and lack of resources led to green revolution, which as of now has turned our begging bowl to agriculturally advanced cereal exporting country.

Pesticide Formulation

Pesticide formulation is the process by which the pesticide is put into a form which can be easily produced, stored, transported and applied by practical methods in order to achieve a safe, convenient economic and effective method of pest control.

When a pesticide active ingredient (a.i) is manufactured, it is not in a usable form as it may not mix well with water or may be unstable. Therefore, it is mixed with other compounds to improve its effectiveness, safety, handling and storage. These other compounds can include solvents, mineral clays, stickers, wetting agents, or other adjuvant. The mixture of a.i. and inert (inactive) ingredients is called a pesticide formulation. Some formulations are premixed while others must be mixed before use. A single a.i. is often made into several formulations.

INTRODUCTION

While the world has been changing during the last few years both politically and economically in unexpected and remarkable way, food security remains an unfulfilled dream of billions of people. With the world population crossing six billion marks, the demand for food grains is increasing at an alarming rate. Increasing population, on the other hand, has led to decrease in cropping area. In order to meet the global food demand we have to increase the productivity. Insects have always been a major cause of yield-loss in agriculture. They account for 20-30% of crop-loss. Several approaches e.g. physical, chemical and biological have been used with varying degree of success to reduce such losses.
 
The insect pest management is one of the most important yield destabilizing factors in almost all the crops. While for some insects, genetic sources of resistance are available in the respective plant germplasm, for many others germplasm is almost devoid of effective resistance genes. It is because of this factor that conventional breeding strategies have not been successful in breeding insect pest’s resistant varieties. The only means available at present for managing the insect is extensive application of insecticides and pesticides. Excessive usage of the pesticides causes, on one hand, environmental pollution and on the other, it forces the insects to develop resistance against these chemicals. Application of the pesticides also imposes additional economic burden on the farmers.

High performance liquid chromatography (HPLC) was developed during late 1960s and early 1970s. Today it is a widely accepted separation technique for both sample analysis and purification in a variety of areas. HPLC, basically a highly improved form of column chromatography and popularly known as liquid chromatography, like other forms of chromatography, whether paper, thin layer or gas chromatography, needs two essential components, the stationary and the mobile phase. It has the unique ability to separate and quantitate residues of polar, non volatile and heat labile chemical compounds. HPLC uses high pressure pumps up to 400 atmospheres that makes it much faster, short and narrow columns packed with micro particulate phase and a detector. To affect a separation, mixture to be analysed is dissolved in a solvent (ideally this solvent is identical to mobile phase) and then forced to flow through analytical column along with mobile phase. In the column the constituents of mixture get resolved and are detected with a suitable detector by a proper choice of column, mobile phase and detector. HPLC is a technique having high degree of versatility. There are several excellent texts published over the last decade which may be consulted for general information on the instrumentation in liquid chromatography