植物耐虫性研究进展

Plant tolerance against insect pests and its mechanisms

本文简要介绍了植物耐虫性的含义、发生范围、耐虫性的进化过程和遗传特性、耐虫性机理以及影响植物耐虫性表达的非生物和生物因子。植物耐虫性机理的研究涉及光合作用能力变化、同化产物的再分配、内源激素的变化、休眠分生组织的激活和补偿生长、储藏器官的利用、植物物候学和植株株型结构的变化等。研究表明, 植物受害后光合作用强度的变化与其耐虫性没有相关性, 有些耐虫植物受害后光合作用能力增加, 有些植物光合作用强度无明显影响或者下降较少;害虫取食为害可促进耐虫植物的同化产物得到最大程度利用, 能激活耐虫植物的休眠分生组织, 产生超补偿作用; 耐虫植物受害部位细胞分裂素含量显著升高; 虫害引起物候学变化小的植物具有较强的耐虫性; 植物的冠层结构、叶形态、根茎比、茎蘖数等植株株型变化与耐虫性有关。影响植物耐虫性表达的因子主要有温度、大气 CO2浓度、土壤营养水平、农用化学物质、植株年龄、害虫分布类型和取食方式、植物共生物等。不同植物在相同温度下对同一种害虫的耐害性差异大,其主要原因可能是由于温度的变化引起同化产物的分配和再分配以及气孔关闭对气体交换和光合作用能力的影响; 生长在高CO2含量大气中的植物, 对害虫的为害有较强耐受性。

The paper reviewed meanings, examples, evolution and genetic traits of plant tolerance against insect pests and its potential mechanisms, as well as abiotic and biotic factors affecting expression of plant tolerance. Potential mechanisms of tolerance including photosynthetic activity, reallocation of available assimilates, change in inner hormone, compensatory growth and activation of dormant meristems, utilization of stored reserves, and changes in plant phenology and plant architecture after the damage. It has been found that there is no direct relationship between photosynthetic activity change of plants after insect pest damage and its tolerance: for some plants the photosynthetic activity is increased, some unaffected, or even reduced. After damage, assimilates of tolerant plants are utilized to the greatest extent, dormant meristems is activated and overcompensation is induced. Insect damage induces a significantly increased supply of leaf cytokinins or root-derived cytokinins in damage place of tolerant plants. Less change in plant phenology may be one of the more widespread mechanisms of tolerance. Plant size, leaf morphology, root-shoot rations, stem number and so on are related to its tolerance. Main factors affecting tolerance expression are temperature, global CO (2) levels, soil nutrient available levels, agrochemicals, plant ages, distribution type and feeding strategies of insects, plant mutualisms, pollinators, endophytic fungi, mycorrhizal fungi and facilitating plants. Under different temperatures the same plants may have different tolerance to the same pest species. The main cause is that change of temperature results in allocation and reallocation of available assimilates and effects of spiracle closing on gas exchange and photosynthetic ability. Plants grown in high CO (2) concentration has stronger tolerance. Soil nutrient level has stronger effects on plant tolerance expression than temperature. High concentration of phosphorus and potassium increases tolerance level. The distribution type of insects within a field can affect plant compensation for damage, and feeding pattern of insects, pollinator movement, infection of endophytic fungi and mycorrhizal fungi can also influence plant tolerance. The importance and application prospects of plant tolerance in integrated pest management were also discussed.