Outline
- Abstract
- I. Introduction
- II. Current Approaches to Insect Pest Management in Organic Farming
- A. Prevention
- B. Biological Control
- C. Chemical Control
- III. Biology of Plant Volatiles
- A. Plant Volatiles: Chemistry and Biosynthesis
- B. Ecological Functions of Plant Volatiles in Plant-Insect Interactions
- IV. Insect Pest Management in Organic Farming Based on Plant Volatiles
- A. Cultivars with Enhanced Indirect And/or Direct Defense
- B. Polyculture
- C. Association with Beneficial Microorganisms
- D. Extracted Plant Volatiles for Pest Control
- V. Conclusion and Perspectives
- Acknowledgments
- References
رئوس مطالب
- چکیده
- کلیدواژه ها
- 1. مقدمه
- 2. رویکردهای رایج برای مدیریت حشرات آفت در کشاورزی ارگانیک
- الف. پیشگیری
- ب. کنترل بیولوژیکی
- پ.کنترل شیمیایی
- 3. بیولوژی (زیست شناسی) مواد فرار گیاهی
- الف. مواد فرار گیاهی: شیمی این مواد و بیوسنتز آن ها
- 4. مدیریت حشرات آفات بر مبنای مواد فرار گیاهی در کشاورزی ارگانیک
- الف. ارقامی با دفاع مستقیم و یا غیر مستقیم پیشرفته
- ب. چند کشتی
- پ. ارتباط با میکروارگانیسم های سودمند
- د. استخراج (عصاره گیری) مواد فرار گیاهی برای کنترل آفات
- 5. نتیجه گیری و چشم انداز آتی
Abstract
Organic agriculture is increasing in popularity worldwide due to the rapidly growing market for organic products. In organic production, insects present a major pest challenge that negatively impacts crop health and yield. To successfully manage an organic farmland, an effective insect pest management program is key. In this review, we first describe the approaches currently used for pest management in organic farming. Next, we review natural plant defense mechanisms, especially those based on plant volatile organic compounds. Chemically complex, plant volatiles have multiple ecological roles in plant-insect interactions including attracting pollinators, acting as cues for foraging herbivores as well as functioning as direct defense, indirect defense, or interplant priming. Based on the ecological roles of plant volatiles, we then discuss in-depth how pest management may be improved through a variety of strategies including using resistant cultivars, polyculture, using beneficial microorganisms such as mycorrhizal fungi and endophytes, and using plant-derived pesticides, all of which are reviewed in the context of plant volatiles. Lastly, integration of these different strategies based on the trait of plant volatiles for a successful and sustainable pest management program in organic farming is discussed.
Keywords: insect pests - organic farming - plant defenses - plant volatilesV. CONCLUSION AND PERSPECTIVES
Pest management is a key component in organic crop production systems. Because synthetic pesticides and genetically modified crops are prohibited in this system, pest management presents a challenging task for the success of organic production. One key strategy currently used for pest management in organic farming involves preventive measures through selection of insect-resistant varieties, planting trap crops, following crop rotation, and nutrient management. Other strategies involve control measures through releasing or attracting natural enemies of herbivores and employing organic pesticides. Facing the challenging task of effective pest management, in this article, we have extensively reviewed and discussed how we may improve current strategies and design new strategies based on the production of volatile organic compounds from various plants. Plant volatile compounds play important roles in mediating complex interactions between plants and organisms in the same ecosystem (Dudareva et al., 2006). These compounds are of great importance to plant defense as well as reproduction.
Volatile production is genetically controlled and can be affected by different biotic (herbivores, microorganisms like mycorrhizae, and endophytes) and abiotic (light, temperature, nutrients) factors. To successfully control pests in an organic system, it is important to understand the interactions of different components in a specific ecosystem. For instance, restriction of use of pesticides may result in increase in the pest pressure in some crop species or varieties. However, it may positively impact the biodiversity in the crop ecosystem and increase natural enemies’ populations. Therefore, it is important to emphasize the integration of different approaches that work synergistically and be in harmony with the nature. In addition to their roles in plantherbivore interactions, plant volatiles are involved in many other aspects of plant biology and ecology, such as defense against pathogens (Pichersky and Gershenzon, 2002). Volatiles released from below-ground tissues may have synergistic or allelopathic activity on the germination and growth of competitive neighboring plants. When leveraging the benefits of plant volatiles for enhanced defense against insects in organic farming, their potential negative impact also need to be considered. More basic research regarding the functions of plant volatiles, especially in an organic agroecosystem, is still needed. While much research in this area is still in its infancy, a multidisciplinary approach involving molecular biology, biochemistry, plant breeding, entomology, crop management and economics can facilitate the investigation and subsequently provide real world solutions for pest control in organic agriculture.