间作和轮作通过根冠互作调控作物产量形成的生理生态机制

Eco-physiological mechanism of crop yield formation regulated by intercropping and rotation through root-shoot interaction

作物轮作和间作是提高农业资源利用效率和作物生产力的重要途径。平衡协调的根冠关系是作物正常生长发育和产量品质形成的保证。轮作能增加土壤养分和有机质含量、改善土壤结构,改变土壤微生物多样性及其生态功能,影响根系形态和功能,进而调控地上部冠层的生长发育和产量品质形成;间作一方面改变地下部微生态,并通过根系间的交流与互作,影响根系形态和功能,另一方面改变冠层小气候,影响作物株型和群体结构特征,调控地上部冠层光合生产、同化物分配和产量形成。间作和轮作通过改变根冠的生态生理打破了原有的根冠关系,并通过根冠互作实现根冠关系再平衡来调控产量和品质的形成。以两种作物宽幅间作、年际种植位置互换为特征的交替间作新模式兼具轮作和间作的作用,能更有效地调节和再平衡根冠关系,促进作物产量形成。本文提出了根冠关系再平衡的观点,并从这一角度论述了作物间作和轮作,特别是交替间作促进作物产量形成的效应和机理。

Crop rotation and intercropping are important ways to improve the utilization efficiency of agricultural resources and crop productivity.The balanced and coordinated root-shoot relationship is the guarantee for the normal growth and development of crops and the formation of yield and quality.Crop rotation can increase the content of soil nutrients and organic matter,improve soil structure,change soil microbial diversity and ecological function,affect root morphology and function,and then regulate the growth and development of aboveground canopy and the formation of yield and quality.On the one hand,intercropping changes the underground micro ecology and affects the root morphology and function through the exchange and interaction between root systems.On the other hand,intercropping changes the canopy microclimate,affects the characteristics of plant architecture and population structure,and regulates the aboveground canopy photosynthetic production,assimilate partitioning and crop yield formation.Intercropping and crop rotation can break the original root-shoot relationship by changing the physiological ecology of root and shoot,and realizes the re-balancing of root-shoot relationship through root-shoot interaction to regulate the formation of yield and quality.The new alternate intercropping model characterized by wide-stripe intercropping and interannual exchange of planting position in two crops has double functions of rotation and intercropping,which can more effectively adjust and re-balance the root-shoot relationship and promote the formation of crop yield.This paper puts forward the viewpoint of root-shoot relationship re-balancing,and discusses the effects and mechanisms of intercropping,especially those of alternate intercropping to promote the yield formation.