Sustainable management on pests by agro-biodiversity

Agro-biodiversity is essential for global food production,livelihood security and sustainable agricultural development.Human communities worldwide have played a central role in shaping nature′s diversity and its associated functions.Both natural processes and human activities have generated and sustained rich genetic,species and ecosystem diversity.Within agro-systems this agro-biodiversity performs many closely inter-related social,economical and environmental functions.1) Promoting food and livelihood security.Dynamic and complex rural livelihoods usually rely on diverse plant and animal both in wild and in different stages of domestication.Different types of agro-biodiversity are used by different people at different times and in different places,hence contribute to livelihood strategies in a complex fashion.2) Maintaining productive and environmental sustainability.In addition to contributing to environmental sustainability,agro-biodiversity helps sustain many production functions both in low input and high input agriculture.Available evidence is summarized for the following functions: soil organic matter decomposition,nutrient cycling,pollination,pest control,yield formation,soil and water conservation,impact on climate and water cycling,biodiversity conservation and influence on landscape structure.3) Contribution on the resilience of rural economies. But this agro-biodiversity has been losing at an alarming rate.This paper identifies the dominating reasons for this loss and outlines the basic methods and mechanisms for the construction and restoration of field biodiversity.After the review of the negative effect of simplified agriculture in the fossil oil driven agriculture and the positive effect of integrating human activity with nature in traditional agriculture,the necessity and possibility of sustainable management of pests by biodiversity in agriculture is discussed,and the general methods used in construction and restoration of field biodiversity was summarized in ecosystem diversity,species diversity and genetic diversity levels.Based on the knowledge of plant pathology,agricultural ecology,plant nutrition science,plant physiology and other related disciplines,the basic principles for sustainable management on pests by agro-biodiversity was summarized into seven aspects,that is groups heterogeneity effect,dilution effect,field micro-environment effect,induced resistance effect,physical obstacle effect,physiological effect and allelopathic effect.It is well-known that fossil oil driven agriculture meets the needs of present generation by paying heavy cost from our future generations.Traditional agriculture has rich ecological philosophy behind,however it is hard to meet the ever-increasing needs of the society.More and more scientists,decision makers and producers are seeking for sustainable agricultural production systems with low input,high efficiency,and high diversity.Agro-biodiversity can improve important ecological functions.It is a golden key for the stable,healthy,productive and sustainable field ecosystem,and for the sustainable management of pests.For this purpose,we should pay our attention to four aspects:(1) the increase of interrelationship among different crop species;(2) the research on dominant pests and their natural enemies with their biological and ecological characteristics and their favorable environmental factors;(3) the discovery of production systems with comprehensive and sustainable management methods to control pests by using agro-biodiversity;(4) the development of integrated agronomic technology and agricultural machinery to match these agro-biodiversity models.