Integrated Pest Management Practices Research Articles

Side‐effect of integrated pest management and conventional spraying on the composition of epigeic spiders and harvestmen in an apple orchard (Araneae, Opiliones)

The effect of two different integrated pest management (IPM) practices and conventional spraying (CHEM) on the composition of epigeic spiders and harvestmen in an apple orchard was investigated over 4 years. Conventional spraying included more frequent and nonselective pesticide applications, whilst IPM plots were treated with selective pesticides and less frequently. One of the IPM plots was undersown with various plantings, the other with grass, and the plot under conventional spraying was covered with weeds. In total, eight species of harvestmen and 65 species of spiders were recorded whose abundance peaked in spring and autumn. Arachnids were on average over the 4 years less abundant on both IPM plots than on CHEM which seems to be due to lower plant density of weed cover. Seasonal oscillations were only slightly different in particular seasons between plots, in particular during spraying. In 1992 the arachnids were a little more abundant on the conventional spraying plot, in 1993 on IPM plots and during subsequent 2 years the difference diminished. The seasonal abundance appeared to be influenced by herbicide applications. Species diversity of all plots were higher than in crop fields, but did not reveal disagreement between plots. The numerical hierarchical classification (TWINSPAN) detected that the composition of arachnids was influenced in particular by annual variation. The arachnid assemblages of the studied plots were not found to be markedly different during the whole study. The effect of IPM practices and conventional spraying on the composition of epigeic arachnids was far less apparent than it was in arboreal species. However, nearly 20% of spiders were found common with crown stratum. Some of them occupied both strata, a few occurred in epigeon only accidently, while others moved vertically during the season. Thus the epigeic fauna seems to support arboreal spiders.

Cost Effectiveness of Pest Management Strategies in Peanut (Arachis hypogaea L.) Grown in North Carolina

Abstract Reducing costs associated with pest management in peanut (Arachis hypogaea L.) production systems in the United States will become increasingly important due to changes in federal legislation that reduced support prices and removed the escalator provision. The federal peanut program may be eliminated completely in 2002 at which time peanut most likely will be marketed at the world price, which is substantially lower than the current quota price. Eight experiments were conducted during 1997 and 1998 to evaluate pest control, pod yield, gross value, and economic return with preventive and integrated pest management (IPM)-based disease, insect, and weed management strategies. Preventive strategies included prophylactic applications of herbicides, fungicides, fumigant, and insecticides. IPM strategies involved host-plant resistance, targeting pesticide applications based on economic thresholds, and other thresholdbased practices to manage pests. Preventive and IPM weed management strategies provided similar economic return in seven of eight experiments. Early leaf spot, caused by Cercospora arachidicola, control was similar when fungicides were applied biweekly or based on weather advisories. However, scheduling fungicide sprays using weather-based advisories eliminated one to three fungicide applications per year. Biweekly applications of fungicides increased damage from twospotted spider mite (Tetranycychus urticae) in one experiment compared with applications using weather-based advisories. Fumigation by metam sodium for Cylindrocladium black rot (CBR), caused by Cylindrocladium crotalarie, was needed in one of three experiments where this disease was present. Resistance of the cultivar NC 12C to CBR was not sufficient to prevent yield and economic loss where damage exceeded 10% plant loss. Iprodione was applied preventatively for suppression of Sclerotinia blight, caused by Sclerotinia minor. However, this disease developed in only one of four experiments where fungicide was applied. Aldicarb applied infurrow and acephate applied postemergence based on damage thresholds controlled tobacco thrips (Frankliniella fusca) similarly in seven of eight experiments. In one experiment, aldicarb was more effective than acephate. Failure to apply chlorpyrifos for southern corn rootworm (Diabrotica undecimpunctata) control resulted in yield and economic loss in three experiments. Chlorpyrifos controlled potato leafhopper (Empoasca fabae) and prevented possible yield loss caused by this insect. Collectively, these data demonstrate the complexity of pest management in peanut and some of the weaknesses associated with current pest control and IPM practices. The importance of accurate identification of pests and detailed field histories also was demonstrated in these studies. Likewise, a thorough understanding of the impact of production practices on pest development and timely implementation of pest control tactics is critical for adequate plant protection.

Managing diffuse environmental contamination from agricultural pesticides: An economic perspective on issues and policy options, with particular reference to Europe

There are widely held concerns over environmental contamination from agricultural pesticide applications, and a current policy objective in many Western European countries is to reduce usage levels. However, it appears that existing arrangements to control usage, and thence contamination, are inadequate to achieve the levels of environmental quality currently demanded; policy innovation and reform are needed. This review examines some of the problems of controlling pesticide contamination, and the potential policy instruments for achieving pesticide use reduction for environmental improvement. Particular attention is given to the role of market mechanisms to achieve environmental policy aims, especially through the introduction of financial incentives for producers to switch to integrated pest management practices involving the use of less pesticides. Instruments such as input taxes seem administratively and politically feasible, but need careful design and implementation if environmental objectives with regard to pesticides are to be achieved. Environmental economics can make an important contribution to practical agri-environmental resource management if linked with more explicit acknowledgement of the characteristics of agro-ecosystems.

Effects of Insecticide Attributes on Within‐Season Insecticide Product and Rate Choices: The Case of U.S. Apple Growers

AbstractWe use a random utility framework to examine within‐season choices of insecticide products and application rates made by U.S. apple growers. Impacts on pesticide choices of insecticide efficacy, environmental safety, user safety, and regulatory attributes, as well as integrated pest management (IPM) practices, are investigated using cross‐sectional data from the USDA Fruit and Nut Chemical Use Survey. The results show that the product and rate choices are most influenced by efficacy and user safety attributes, respectively. Impacts of IPM practices are mainly on the choice of insecticide products, but effects differ by practice and by product.

Effective control of yellow stem borer and rice leaf folder in transgenic rice indica varieties Basmati 370 and M 7 using the novel δ-endotoxin cry2A Bacillus thuringiensis gene

Transgenic rice indica varieties Basmati 370 and M 7 expressing the novel cry2A (Bt) insecticidal gene were generated by particle bombardment. Molecular and biochemical analyses in R0 and R1 populations confirmed stable integration and expression of this novel Bt transgene. We estimated that the gene product was expressed up to 5% of total leaf protein. Insect feeding bioassays demonstrated that the Cry2A protein was effective against the yellow stem borer and the rice leaf folder, two major rice pests in the Indian Subcontinent. This is the first report of the control of major rice pests using this specific Bt gene. The cry2A gene can now be used in combination with other insecticidal genes for pyramiding resistance against insect pests. This will delay, or perhaps in combination with integrated pest management practices, prevent evolution of insect populations resistant to single insecticidal genes.

Southeastern Tomato Growers Adopt Integrated Pest Management

Multidisciplinary integrated pest management (IPM) teams from seven states in the southeastern United States (Alabama, North Florida, Georgia, Kentucky, North Carolina, South Carolina, and Tennessee) met to develop standards for adopting IPM in fresh-market tomato (Lycopersicon esculentum L.) production. Teams were composed of growers, private consultants, extension personnel, and faculty. IPM practices available for use on tomatoes in the southeastern United States were identified and a survey to assess the current level of adoption of IPM practices was developed. The survey also allowed growers to identify insect, disease, and production problems; beneficial technology and research developments; and other information relevant to IPM adoption. In northern Florida, Georgia, Kentucky, North Carolina, and South Carolina, IPM adoption by tomato growers was classified as medium or high on >75% of the fresh-market tomato acreage surveyed. It appears these states may have met the federal mandate for IPM adoption. Tomato producers listed early blight, late blight, bacterial spot, bacterial speck, and bacterial wilt as the main disease problems; tomato fruit worm, thrips, and aphids as the primary insect problems; and poor weather conditions, government regulation, and labor as their primary production problems. Twenty-six percent of the producers throughout the region felt that the development of insect- and disease-resistant varieties would be most helpful to increase production.

Integrated Pest Management perceptions and practices and insect populations in grocery stores in south-central United States

Objectives of this study were to examine Integrated Pest Management (IPM) perceptions and practices in grocery stores, and to quantify by location, the occurrence and abundance of stored product insects. The first objective was accomplished by surveying grocery store employees of 322 grocery stores in Oklahoma, Arkansas and Texas using a 28 question survey. Grocers lacked knowledge of IPM practices, yet over half were interested in learning more about IPM. Present management practices are pesticide intensive with limited use of alternatives including sanitation, stock rotation and trapping. Presently, grocers depend on pest control companies to find and control problem insects in the store. Insects reported by grocers as problems were weevils, cockroaches, flies and ants. Extensive trapping in eight Oklahoma grocery stores targeted pet foods, cake mixes, and back room areas. Trapping studies showed stored product insects were abundant in all stores. The most prevalent insects found in traps included the Indian meal moth, Plodia interpunctella (Hübner); merchant grain beetle, Oryzaephilus mercator (Fauvel); and drugstore beetle, Stegobium paniceum (L.). Stored product insects were concentrated in pet food areas and were readily found in the stores.

Economic Impact of Insecticide Resistance in the Colorado Potato Beetle (Coleoptera: Chrysomelidae) on the Michigan Potato Industry

Insecticide resistance in Colorado potato beetle, Leptinotarsa decemlineata (Say), in Michigan was first reported in 1984 but caused severe economic problems beginning in 1991. Surveys conducted by the Michigan Potato Industry Commission and Potato Growers of Michigan from 1991 through 1994 document the increased Colorado potato beetle control costs and yield losses resulting from insecticide resistance. In 1991 and after, statewide mean control costs were as high as $306/ha; costs for districts most seriously affected were as high as $412/ha. This is in contrast to $35-74/ha in the upper peninsula of Michigan, where resistance is not a problem. Yield losses were as high as 12.2% statewide and as high as 20.5% in seriously affected districts. Costs plus losses to the industry were $13.3 million in 1994 (13.7% of crop value). In response to these losses, nearly 100% of the crop was under some type of integrated pest management program. Scouting (96% of crop area) and crop rotation (78% of crop area) were the most common integrated pest management practices. The introduction of new insecticides may reduce or eliminate yield losses. However, costs of resistance will continue to accrue because relatively inexpensive insecticides are no longer effective and newly developed products are up to 5 times more costly. Long-term increased cost to the Michigan industry caused by insecticide resistance in Colorado potato beetle is estimated at $0.9 to $1.4 million/yr ($44 to $69/ha; $18 to 28/acre).

Pest Management Practices of Crop Consultants in the Midwestern USA

A mail survey was conducted of independent crop consultants in 12 midwestern U.S. states working in corn (Zea mays L.), soybeans [Glycine max (L.) Merrill], wheat (Trilicum aestivum L.), and grain sorghum (Solghum bicolor L. Moench.) during 1993. The survey was conducted to document the acreage of crops monitored by crop consultants, and some of their operational characteristics. Kansas and Nebraska had the greatest reported acreage of crops scouted, over 3 million and 1 million acres, respectively. Total acres scouted were highest for corn, followed by soybeans, wheat, alfalfa (Medicago sativa L.), and sorghum. Acres contracted with crop consultants varied from 0.4 to 40.0% of the total 1993 harvested acres, depending on state and crop. The most common interval reported between field visits was once a week. Averaged over all states, the highest consulting fees were charged for alfalfa ($4.80), with less charged for corn ($4.31), sorghum ($4.26), soybeans ($4.07), and wheat ($3.74). There was a great range in fees within crops across the region (e.g., corn fees varied from $3.21-6.13/acre). Planting time application of insecticides was the most commonly used corn rootworm (Diabrotica virgifera virgifera LeConte and D. barberi Smith & Lawrence) control. Postemergence applications of insecticides for larval rootworms (cultivation time applications and chemigation) were used primarily in Kansas and Nebraska. Foliar sprays for adult corn rootworm control were also most common in these states. Use of crop rotation varied greatly across the region (23.8-83.7% of acres were corn after another crop). Additionally, across all states except Missouri, there was a significant correlation between frequency of rotation in corn and insecticide use against corn rootworms; ie., states with higher frequencies of rotated corn treated a lower percentage of corn acreage for corn rootworm controL The diversity of crop consultant activity across the region has implications for future adoption of IPM practices on midwestern field crops.

Activity pattern of fish in rice fields

The culture of fish in rice fields is a traditional integrated farming practice which faced a decline during the Green Revolution in Asia but today has new scope with the increased adoption of integrated pest management practices. A widely used system is digging a pond within or adjacent to the rice field so that fish have free access to pond and field. Systematic knowledge on the activity pattern of fish in rice fields is lacking to date, but is crucial for understanding their role in this ecosystem as well as their potential as biocontrol agents of rice pests. We therefore conducted a study to determine the spatial and temporal distribution of Oreochromis niloticus (mixed sex), O. niloticus (all male) and Cyprinus carpio at three times of day (07:00 h, 12:00 h and 17:00 h) during early, middle and late rice crop development in the dry and wet season. Nets were installed in the rice fields that served as barriers against fish movement during sampling. In addition, ponds were netted to allow sampling of all fish. Results show that regardless of fish group or sampling time, more than 50% of the fish can be found in the rice field. In the wet season, fish distribution within the rice field was uniform with 16–18% of the fish sampled in each of the four field compartments, whereas in the dry season significantly ( P < 0.01) more fish were caught in the first compartment adjacent to the pond. The results are discussed in view of the changing conditions in the rice field due to crop development. The presence of large numbers of fish in the rice field provides evidence for the hypothesis that fish are potentially important predators of rice pests.

Integrated pest management of coffee for small-scale farmers in East Africa: needs and limitations

Coffee in East Africa (Kenya, Tanzania and Uganda) is an important cash and export crop for small-scale farmers. The crop suffers heavy yield losses due to damage caused by a wide range of indigenous pests (insects, diseases, nematodes and weeds). Current recommended pest control measures include a combination of cultural, resistant/tolerant cultivars and the use of broad spectrum chemical pesticides. Chemical pesticides are far more popular at the farm level than any of the other recommended pest control measures. Coffee pest control strategies are often aimed at individual pests with little consideration of the implications for the total coffee pest complex and its agro-ecosystem. This unilateral approach has resulted in increased pest pressure on coffee and some of its companion crops, outbreak of new pests of coffee, development of pest strains resistant to the cheap and commonly available chemical pesticides, increased environmental problems, increased health risks to man and livestock and an overall increase in the costs of coffee production, thus forcing many farmers to neglect their coffee plantations. Measures to alleviate the above problems, particularly the high production costs, are needed to improve coffee production and increase the cash return to the small-scale farmer. Integrated pest management (IPM) offers the best prospects for solving the above problems. However, lack of national IPM policies, poor extension systems, inefficient research-extension-farmer linkage and the lack of a holistic approach will delay the development and implementation of appropriate, acceptable and sustainable IPM practices.

Reducing the Pollution Potential of Pesticides and Fertilizers in the Environmental Horticulture Industry: II. Lawn Care and Landscape Management

Optimizing growing conditions and, thereby, plant growth reduces the susceptibility of plants to many disease and insect pest problems. Educating lawn or landscape management professionals and homeowners about plant health management reduces the need for chemical intervention. Pesticides combined with N and P fertilizers contribute to water pollution problems in urban areas; thus, it is important to manage the amount, timing, and placement of chemicals and fertilizers. To educate consumers applying pesticides and fertilizers in residential gardens, we must educate the sales representatives and others who interact most closely with consumers. Evidence suggests that knowledge about the effects of chemicals is limited and that warning labels are not read or are ignored. Integrated pest management (IPM) offers alternatives to conventional chemical treatments, but such methods are not used commonly because of their relatively high cost and their uncertain impact on pests. Pest detection methods and using pest-resistant plants in landscapes are simple and, in many cases, readily available approaches to reducing the dependence on chemical use. Research on effective, low-cost IPM methods is essential if chemical use in landscape management is to decrease. Current impediments to reducing the pollution potential of chemicals used in the landscape include the limited number of easily implemented, reliable, and cost-effective alternative pest control methods; underfunding of research on development of alternative pest control measures; limited knowledge of commercial operators, chemical and nursery sales representatives, landscape architects, and the general public concerning available alternatives; reluctance of the nursery industry to produce, and of the landscape architects to specify the use of, pest-resistant plant materials; lack of economic or regulatory incentive for professionals to implement alternatives; inadequate funding for education on the benefits of decreased chemical use; and the necessity of changing consumer definition of unacceptable plant damage. We need to teach homeowners and professionals how to manage irrigation to optimize plant growth; use sound IPM practices for reducing disease, weed, and insect problems; and minimize pollution hazards from fertilizers and pesticides.

Arthropod pest and natural enemy abundance under second-level versus first-level integrated pest management practices in apple orchards: a 4-year study

The authors conceive of second-level integrated pest management (IPM) in apple orchards as involving integration of multiple management tactics across all classes of pests. From 1991–1994, a second-level IPM pilot project was carried out in six commercial Massachusetts apple orchard blocks (2–4 ha) in which pest and natural enemy populations and injuries to fruit were compared with those in adjacent blocks receiving first-level IPM practices (considered to be integration of tactics within a single class of pests). The approach to second-level IPM was use of chemically based tactics for arthropod, disease and weed control during the first part of the growing season (up to mid-June for arthropods) and thereafter use of only biologically based tactics (cultural, behavioral and biological control methods). This article deals with findings on arthropod management. As expected, total injury to fruit by insects causing damage before mid-June did not differ between second-level (4.7%) and first-level (4.8%) IPM blocks. Total injury to fruit by insects active after mid-June averaged about the same (0.5%) in both types of blocks in 1991 and 1992, but in 1993 and 1994 it averaged more in second-level blocks (4.8%) than first-level blocks (1.9%). This was particularly true for Grapholitha prunivora Walker and leafrollers and less so for Cydia pomonella (L.) and Rhagoletis pomonella (Walsh). Among foliar pest arthropods and their natural enemies, populations of aphids and aphid predators and populations of spider mites and mite predators averaged about the same in both types of blocks. Populations of leafminers averaged lower and parasitoids of leafminers averaged greater in second-level blocks. Populations of leafhoppers averaged greater in second-level blocks. Pesticide use against fruit-damaging insects averaged 37% less in second-level than in first-level blocks, but against foliar-damaging arthropods, it was not less. Some refinements of second-level IPM tactics for arthropod control are needed before second-level IPM practices can be recommended broadly to commercial growers in New England as an economical and reliable alternative to first-level IPM.

Integrated Pest Management of Insects, Plant Pathogens, and Weeds in Dryland Cropping Systems of the Great Plains

In this article, we trace the development of the concepts and practices of Integrated Pest Management (IPM). Tactics used in IPM of insect pests, plant pathogens, and weeds are discussed, with particular emphasis on application to dryland cropping systems of the Great Plains. Recommendations are made for guiding the development of IPM in such systems. Introduction Insect pests, plant pathogens, and weeds pose a considerable threat to the dryland cropping systems of the Great Plains. The concepts and practices of Integrated Pest Management (IPM) provide an approach to managing these pests. The objectives of this paper are to review and synthesize existing information about IPM and to discuss the application of IPM specifically in the dryland cropping systems of the Great Plains. Literature Summary Many descriptions of IPM have been provided in the literature. The description used here is: “IPM is the judicious use and integration of various pest control tactics, in the context of the associated environment of the pests, in ways that complement and facilitate biological control and other ecological processes that reduce pest impact, to meet economic and environmental goals. IPM addresses the basic causes of pest problems in a holistic manner.” Table 1 lists categories and sub-categories of IPM tactics. Decisions regarding what tactics to use and when and how to use them are a critical aspect of IPM, The concept of the economic injury level (EIL) was developed as a decision tool for managing insect pests in the 1950s and has become a major component of IPM. There are, however, limits to its usefulness, particularly in dryland cropping systems. Study Description Published IPM practices specific to the dryland cropping systems of the Great Plains were reviewed and discussed, with particular emphasis on the use of the EIL and the tactics of pest resistant cultivars, crop rotations, and planting date. In addition, management systems were reviewed for wheat streak mosaic virus, wheat stem sawfly, and Russian wheat aphid. Applied Questions What are the IPM tactics that are most appropriate for IPM in dryland cropping systems of the great plains? The tactics to be emphasized in dryland systems are those that can be designed into the cropping system to reduce the likelihood of pest problems developing. Examples are: cultivars resistant to the pest, crop rotations, certain types of biological control, and planting date adjustment. Tactics such as pesticides, that are applied once a pest problem is active, have limited usefulness because of the expense of gathering information about the current status of pests and the cost of applying the tactic. In low value, dryland cropping systems, the potential increase in economic return from the use of these tactics typically does not justify the cost. Is the EIL concept useful in IPM in the dryland cropping systems of the great plains? Yes. However, its usefulness is limited by the relatively low value of the crops grown in dryland systems and the expense associated with acquiring and interpreting the information required for use of the EIL in IPM decisions. Another important limitation to the usefulness of the EIL is the expense of applying the tactics (mostly pesticides) that are available for use against an active pest problem. Recommendations To best meet the needs for IPM in the dryland cropping systems of the Great Plains, management tactics must be built into cropping systems design. This will require a systems approach with teams of individuals from many disciplines working together. Adoption of such systems will be enhanced if the teams include expertise in research and extension and if producers are closely involved from the earliest stages. Table 1. IPM tactics. Pesticides Host plant resistance Biological control Importation and release Conservation Augmentation Cultural practices Rotations lnterplantings Cover cmps Planting density Pest-k planting materials Planting date Harvesting date Tillage Sanitation Field size Adjacent land uses Soil fertility management lmgation management

Survey of Integrated Pest Management Practices in Central Illinois

The Clinton Administration set a goal to develop and implement integrated pest management (IPM) programs on 75% of the managed acres in the USA by the year 2000. In order to document current IPM practices and identify limitations to further adoption, a direct mail survey was sent to 988 farmers in eight central Illinois counties. Survey results indicated that 65% of the farmers hired a custom herbicide applicator, but only 7% hired a professional crop scout to monitor their fields. Forty one percent of the farmers reported they scout their fields weekly, while an additional 35% said they scout fields at least two to three times per growing season. Only 3% of the farmers said they seldom or never scout their fields. Economic thresholds were used to make insect control decisions by 34% of the farmers. In contrast, only 9% of farmers used economic thresholds as a basis for weed management. Sixty nine percent of the farmers responding to the survey were very concerned about the effects of pesticides on applicator health. Understanding how farmers make their pest management decisions may help identify current barriers to the successful adoption of IPM.

Weed Mapping as a Component of Integrated Pest Management in Cranberry Production

A system of mapping weed infestations in cranberries (Vaccinium macrocarpon Ait.) was developed that enables growers to incorporate integrated pest management practices into their weed control program. This system provides growers with information on the location of weeds and the area of weed patches, but differs from other weed mapping systems in that information on control priorities is included on the maps. Weed management efforts can then be directed to the most economically damaging weeds first. The mapping system also provides growers with a permanent record that can be used to communicate with staff and to evaluate weed management strategies.

Productivity and Profitability of Paddy Production in the Muda Scheme, Malaysia

The Malaysian government's policies of price support and subsidies for rice production, free fertilizers and provision of agricu ltural extension services have enabled the farm ers to increase rice output over tim e, particularly after 1984. The Muda A gricultural D evelopm ent A uthority (M A D A) im proved the efficiency of water distribution and w ater use by investm ents in tertiary canals and farm roads and by improved data feedback systems. The farmers have also responded to labour and water shortages by adopting direct seeding in place of transplanting of rice and by integrated pest management practices. This paper presents a description of levels and changes in productivity and profitability of paddy production in the M uda irrigation scheme in Malaysia. It has been noted that, over the 1980s, there w as a substantial reduction in rainfall and overall availability of water resources for irrigation in the region. Despite these adverse factors, farm ers were able to increase total crop output by about 16% over the decade (1980-82 to 1990-91). Paddy output per unit of w ater released from the reservoirs increased by alm ost 45% in that period. The cost of production of paddy declined marginally over time for land owners as a result of reduced labour costs for transplanting rice. For tenants, the cost of production increased by about 17% owing to a substantial (50%) rise in land rents. H ence, higher yields have not resulted in higher incomes for farm ers despite an increase in output price subsidies.

Modern varieties ? Their real contribution to food supply and equity

Green revolution technology, centered on high-yielding varieties, has revolutionized rice production since the late 1960's. These varieties are characterized by higher yield potential, better grain quality, shorter growth duration, multiple resistance to diseases and insects and tolerance to problem soils. High yielding varieties are now planted to 70% of the world's rice lands. Most countries in the Asian rice belt have become self sufficient in rice and some have exportable surpluses. The real prices of rice have declined in most countries. This price decline has benefitted the urban poor and rural landless. Labor requirement has also increased from higher intensity of cropping and resulted in growth of income of the rural landless workers. Availability of rice varieties with multiple resistance reduced the need for application of agrochemicals and facilitated the adoption of integrated pest management practices. The population of rice consumers is increasing at the rate of 2% annually. However the rate of growth of rice production has slowed to 1.2%. To reverse this trend, rice plant types with higher yield potential are being developed.

Development of an Integrated Pest Management Module for Cotton in Andhra Pradesh

In an attempt to develop an integrated pest management (IPM) strategy for cotton pests four modules comprising integrated pest control tactics, judicious use of pesticides, farmer's practice and untreated control were evaluated. The approach, consisting of limited use of pesticides coupled with biocontrol measures and other resistance management strategies, was found economically viable for sustaining cotton production in addition to conserving and augmenting natural enemies in the cotton ecosystem. IPM practice also resulted in a higher cost:benefit ratio (1:5.3 and 1:6.1) in comparison with the farmer's practice (1:2.5 and 1:1.6).

ALTERNATIVE MANAGEMENT TECHNIQUES FOR ORCHARDS

Concerns about the impacts of agricultural practices on the environment dictate that all management techniques must be examined from the perspective of minimizing such impacts. Integrated pest management practices such as scouting, use of biological controls, improvement of pesticide application techniques, tree-row-volume spraying, and consideration of the environmental impact of alternative chemical controls offer opportunity for minimizing the adverse impact of pesticides. Improved spray equipment with canopy sensors and spray recovery systems improve deposition and reduce pesticide waste. Applying nutrients on the basis of need as indicated by leaf and soil analyses offers the best means of assuring optimal crop performance and minimizing the potential for contamination of surface and ground water supplies. Soil management practices must be evaluated for their potential to minimize soil erosion and competition, and for their potential contribution to pest management. Ground covers that are nonsupportive of nematodes, disease, or insect pest populations merit additional research. Methods for managing ground covers with low rates of growth regulators or herbicides to minimize invasion by problem weeds, reduce the need for mowing, and regulate competition, while retaining their beneficial attributes in minimizing soil erosion and maintaining soil structure, would be advantageous to orchardists and the environment.