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旱地小麦在进化过程中经受了自然和人工的双重选择,其中人工选择在品种驯化和改良过程中扮演了关键的角色.本文综述了人工选择下旱地小麦进化特征、生理可塑性、形态可塑性和种群属性演变等几个相对独立、但又相互联系的问题,探讨了旱地小麦适应逆境胁迫的生理生态机理,并勾画了其进化路线.在旱地小麦从二倍体到六倍体的漫长进化历程中,自然选择对小麦适应外界环境起到关键作用;随着人工选择的介入,以产量为主要目标的性状选择不断得到强化,从群体上呈现适应逆境的形态特征.人工选择下旱地小麦的水分及养分利用效率不断提升,生物量分配呈现出地下部减少、地上部增加的分配特征,对密度胁迫和高温胁迫的耐受性不断增强,但单位面积光合速率呈逐渐降低趋势.旱地小麦生产是复杂的群体过程,而非简单的个体反应.人工选择提高了旱地小麦的种群适合度和个体繁殖分配,强化了与环境的协同性,却弱化了其自然种群属性.本文还对旱地小麦的进化图进行了描绘,对气候变化下旱地小麦育种和栽培管理提出几点建议.
Dryland wheat has undergone both natural and artificial selection during its evolution, and artificial selection plays a key role in species domestication and improvement.This paper reviewed the evolutionary characteristics, physiological plasticity, morphological plasticity and population properties of dryland wheat under artificial selection Evolution and other several relatively independent but interrelated issues discussed the physiological and ecological mechanisms of dryland wheat to adapt to the stress of stress and outlined its evolutionary path.In the long evolution of dryland wheat from diploid to hexaploid, Natural selection plays a key role in adapting wheat to the external environment. With the intervention of artificial selection, the selection of traits with yield as the main objective is continuously strengthened, and the morphological characteristics of adapting to adversity are presented from the group. Artificial selection of water and nutrients of dryland wheat Utilization efficiency is increasing, the biomass allocation shows the decrease of the underground part, the increased distribution characteristics of the shoot part, the increasing tolerance to the density stress and the high temperature stress, but the photosynthetic rate per unit area shows a decreasing trend. The dryland wheat production is complex The process of grouping, rather than simple individual responses, increases the availability of small drylands Wheat population fitness and individual reproductive allocation, and strengthen the synergy with the environment, but weakened its natural population attributes.This paper also described the evolutionary map of wheat in dryland, the climate change in dryland wheat breeding and cultivation management Point suggestions.