Rice Crop Current Developments

GeoJournal, 1995

Losses caused by pests remain an important constraint to achieving high rice yields. Potentials of protecting these losses have stimulated innovations in pesticide development. Today the rice pesticide market is valued at US $ 3.0 billion per year. With reducing land available for rice production and increasing demand for food production, attention is turning towards intensification through higher fertilizer inputs and cropping. Such intensifications may in turn increase pest intensities and demand for more pesticides.

CABI Reviews, 2017

Rice is a staple food and the foundation of national stability and economic growth in many developing countries. Rice pests are major biotic constraints limiting rice production globally. This review discusses the biology, ecology, global distribution and plant damage and yield losses caused by insect pests, plant diseases, nematodes, rats and weeds. The interactions among insects, weeds and diseases are discussed. A proposed conceptual framework for arthropod pest management in organic crop production is explained. In this framework, arthropod pest management strategies are classified into four 'phases'. The framework prioritizes pest management options that will prevent damaging levels of pests (phase 1 and 2) and minimize the need for curative actions (phases 3 and 4). We adopt and modify this conceptual framework to structure a discussion on various rice pest management options in rice ecosystems. A detailed package of practices for managing rice pests is given. The rela...

Crop Protection, 2012

This review addresses four principles on which sustainable pest management in rice is to be grounded. The goal of modern pest management is to contribute to agricultural sustainability, with its different facets (food security, balanced relations between man-made and natural ecosystems, conservation of ecosystem services). The four principles are considered in turn within the classic Human-Pest-Environment-Crop framework. Biodiversity, as a first principle, is fundamental to the functioning of food webs. The second principle, host plant resistance (HPR), is a pro-poor, and an often highly efficient element that critically contributes to sustainable crop protection. HPR needs to account for the other principles in its implementation in order to sustain durable resistances over time and space. The third principle, landscape ecology, encompasses inter-linked levels of spatial hierarchies governing the performance of systems (pests, host plants, plant genotypic make-ups, plant and crop physiology, trophic chains, and the physical environment). The fourth principle, hierarchies, concerns the different levels of hierarchy in a landscape, from biological to social. This principle concerns the very fabric of human societies, which involve perceptions, knowledge, and attitudes, which translate into decision-making at several scales, from the individual farmer to policy-makers. This principle thus addresses psychological, policy, and decision-making dimensions. In this review, all organisms that may be harmful to rice are referred to as 'pests', including pathogens and animal pests. We do not address all rice pests, but proceed through a few key examples, nor do we enter into the specifics of pest management strategies covering the range of rice production situations. This is because of the very large range of rice pests, of the corresponding diversity of rice production situations worldwide, of the unprecedented rate of diversification of rice production in response to environmental, climatic, social, and economic drivers, and lastly because plant protection in rice faces emerging crop health challenges that continually call for new solutions in new contexts. The review shows that the considered framework e Human-Pest-Environment-Crop e applies, with each of its summits having a different bearing depending on the pest considered. The review further underlines the need for basic research across a range of disciplines, with novel approaches and methods, as well as the need for connecting hierarchy levels, from farmers, to consumers, to societies, the environment, and to policies.

Biological Control of Crop Diseases, 2002

There is sufficient need to document all the available data on biological control of rice diseases in a small volume. Part of this need rests on the global importance of rice to human life. In the first chapter, I have tried to show that rice is indeed life for most people in Asia and shortages in production and availability can lead to a food crisis. While rice is cultivated in most continents, biological disease management attains special relevance to rice farmers of Africa, Asia, and also perhaps, Latin America. These farmers are resource-poor and might not be able to afford the cost of expensive chemical treatments to control devastating rice pathogens such as Magnaporthe oryzae (blast), Xanthomonas oryzae pv. oryzae (bacterial leaf blight), Rhizoctonia solani (sheath blight) and the virus, rice tungro disease. In an earlier volume that I developed under the title, Biological Control of Crop Diseases (Dekker/CRC Publishers, 2002), I included transgenic crops generated for the management of plant pathogens as biological control under the umbrella of a broad definition. Dr Jim Cook who wrote the Foreword for the volume lauded the inclusion of transgenic crops and induced systemic resistance (ISR) as a positive trend toward acceptance of host plant resistance as part of biocontrol. I continue to subscribe to this view. This volume is small but presents adequate and important information on major rice diseases and research on biological control of rice diseases. If I presented the information on biological control alone, I feared that the reader will not get the whole picture. I do hope that this volume will be useful as a reference volume for all students and scientists in crop sciences and plant pathology. More than two third of the work that is covered in this volume comes from research that was carried out in my laboratory at the University of Madras in southern India during 1980-2006 and the research group that was headed by Dr. T. W. Mew at the International Rice Research Institute (IRRI) in the Philippines. A number of Ph.D dissertations were prepared from the research that was carried out in my laboratory and the reader has a chance to come across these in literature cited under each chapter of the volume. As I prepared the volume I realized how fortunate I was v vi Preface to have all these graduate students do doctoral research on biocontrol of different rice diseases and also felt thankful for the opportunities I have had to associate with Drs. Tom Mew and Swapan Datta at IRRI.

Integrated Pest Management Reviews, 1999

Deepwater rice has a distinctive pest complex due to prolonged deep flooding, extended growth duration and a complex environment. Flooding smothers weeds, prevents population buildups of some pests and diseases, and stimulates new growth which may compensate for early damage. Major pests are adapted to these aquatic conditions and exploit the succulent growth and mild weather extremes of this period. In Asia, yellow stem borer causes widespread damage by producing a loss of bearing stems, and lighter or empty panicles. No appropriate measures are known and control of this major pest is a daunting challenge. Stem nematode severely damages rice in several areas but varietal resistance is effective. Rats and hispa beetle are also injurious and many lesser pests are known. In West Africa's smaller Deepwater rice area, stem borers, leafeaters, birds and rats are damaging but their effect on yield is obscure. Farmers commonly employ cultural control methods, and insecticides are used in some areas but diseases are not treated. Pesticide use is restricted by application difficulties, contamination concerns and the low value of the crop. In Asia and Africa wild rices, grasses and sedges compete fiercely with rice before flooding; herbicides are not generally used but many farmers hand weed though the extent of yield loss is poorly understood. Pest management research in deepwater rice is difficult because of the nature of the agroecosystem. Most research has been carried out in Asia but the volume has seriously declined over the last decade.

Plant protection, 2023

This review article delves into the impact, epidemiology, and management of sheath blight disease in rice, caused by Rhizoctonia solani, which is a pernicious pathogen causing severe quality and production losses globally. Rice is a staple crop for almost two-thirds of the world's population, and sheath blight disease significantly affects rice cultivation in many countries, causing substantial annual losses in grain yield. The article provides comprehensive insight into the biology of the pathogen, including its host range, symptoms, disease cycle, and factors influencing its severity. In particular, the pathogen's virulence factors and the underlying mechanisms of its pathogenesis are explored in detail. The review also highlights the significant economic implications of sheath blight disease in rice and the consequent impact on food security and the livelihoods of farmers. Various management strategies, including chemical, cultural, and biological control measures, are discussed in this manuscript. These strategies offer potential solutions to mitigate the devastating effects of sheath blight disease on rice crops. In particular, the review emphasizes the importance of integrated pest management strategies that combine multiple control measures, including the use of resistant cultivars, fungicides, and cultural practices, to achieve long-term sustainable management of the disease. The manuscript concludes with recommendations for farmers, researchers, and policymakers working in agriculture sector to combat the disease's threat and reduce crop losses. The findings of this review article can serve as a valuable resource for stakeholders in the rice production industry to enhance their understanding of sheath blight disease and develop effective management strategies to protect the rice crop's health and yield.

Sheath blight of rice caused by Rhizoctonia solani Kuhn [teleomorph: Thanatephorus cucumeris (Frank) Donk] is of worldwide occurrence and is known to cause substantial yield losses. It is a major production constraint in high yielding varieties under intensive rice production systems. The pathogen has a very wide host range and exhibits considerable pathogenic and molecular variability. Due to non-availability of resistant cultivars, the management of sheath blight primarily relies on chemical control. However, the disease can be managed effectively through integration of effective cultural practices, botanical pesticides, bio-control agents and fungitoxicants. In this article, the information available on various aspects of this disease has been presented and discussed alongwith future strategies for disease management.

The golden apple snail or GAS (Pomacea canaliculata) is an important invasive pest in irrigated rice that feeds on young rice plants. In many countries in SE-Asia, governments have recently decreased their support of training courses for snail management, because farmers are now considered to know how to effectively manage this pest. Although a great number of sustainable control methods is recommended which do not involve the use of pesticides, it is uncertain whether these are taken up by farmers. Probably, the easiest way to control GAS, is the application of synthetic 'instant kill' molluscicides, which can have detrimental effects on the environment, non-target species, and health. The aim of this study was to develop ideas for solutions on how to achieve a sustainable management of GAS without or at least a decreased use of molluscicides. In a large-scale approach, we conducted interviews with rice farmers in seven regions across Vietnam and the Philippines, assessing the participation in training courses, knowledge on snail ecology, the methods of controlling and the utilization of the snail, and the farmers' suggestions on how to improve pest snail control. Only 23% of the farmers had previously received training in GAS management. We found that training neither had positive nor negative effects on the number of sustainable methods applied, molluscicide avoidance, concern about using molluscicides, or on the farmers' knowledge about GAS. As much as 74% of the respondents applied molluscicides. Contrary to recommendations, farmers applied only few sustainable control methods. All farmers had clear knowledge gaps about GAS, especially in species identification, which can even further the ongoing decline of native mollusks in rice landscapes. We conclude that the decision to phase out information campaigns has been taken to rash, and that trainings in our study regions carried through previously had limited success, and thus need revision. To decrease molluscicide use, and to promote sustainable management on the large scale, we synthesized our results, and we suggest that information for farmers might be provided through media often accessed, such as TV, radio or the internet (e.g. by entertainment − education). We further discuss the potential of community cooperation to achieve sustainability. As there are distinct limitations to these approaches, we have developed the concept of local GAS management and utilization companies (GASMUC) which could take over sustainable control and utilization of GAS, and native mollusk conservation for an entire community.

Trends in Biotechnology, 2009

This book deals with basic information on the biology and factors of abundance of common insect pests of rice