Genetical studies on the Response Mechanisms of Crops to Environmental Changes of Temperature

从遗传性状表达的角度，从群体水平、个体水平和植物新陈代谢水平研究作物对环境温度变化的响应；在群体水平研究中，根据植物营养条件对环境效应的响应，利用计算机图像分析技术诊断作物形态和颜色的变化；在个体水平研究中，研究植物在几个生长阶段对温度的响应特征。将水稻离体根培养在液体培养基中，从品种比较来看，它们对温度的反应与单株非常相似。我们可以分离出几个对环境温度有不同反应能力的人工突变体。在这些突变体中，我们现在把注意力集中在减数分裂阶段具有不同抗冷性的突变体上，因为日本东北地区的冷害需要…此外，从水稻植株发育过程的基因表达来看，水稻营养生长期存在从幼体到成体的阶段转换，并说明了温度对这一阶段转换的影响。水稻花粉体外培养的发育受温度的影响很大，不同的基因型对温度的反应能力也不同。在代谢水平的温度响应研究中，对大麦的抗冷性进行了研究，指出甜菜碱在叶片中的积累与抗寒性密切相关。我们分别从水稻和油菜中克隆了几个花药特异基因和花蕾特异基因。植物在花器官发育过程中的温度响应研究正在进行中。同时对白菜型油菜转化体系进行了研究，以获得转基因植株。可选育出再生能力强、抗药性强的菌株。较少

Response of crops to the environmental changes of temperature was studied at the levels of population, individual and metabolism of plants in view of genetical character expression.In the studies at population level, changes of shape and color of plants were diagnosed by computer image analysis in view of plant nutritional conditions responding to environmental effect.In the individual level studies, several features of the response to temperature were investigated on the plants at several growth stages. The excised radicles of rice plant were cultured in a liquid medium,and their responses to temperature were very similar to that of individual plants in view of varietal comparison. We could isolate several artificial mutants that had different ability of response to environmental temperature. Of these mutants, we are now concentrating our attention to the mutants which has different chilling resistance at meiotic stange, because the chilling damage in the Tohoku district in Japan nece … More ssitates the strong chilling resistant varieties.Furthermore, we could point out the existence of phasic transition from juvenile to adult during vegetative growing stage in rice in view of gene expression of developmental program of plant, and the effect of temperature to the phasic transition was illustrated. The development of rice pollen in vitro culture is affected by temperature profoundly, and the response ability differed among genotypes.In the studies on the temperature response at the metabolic level, could resistance of barley was investigated and it was pointed out that accumulation of glycinebetaine in leaves related closely to the resistance to cold. We could clone several anther specific genes and flower bud specific genes from Oryza sativa L. and Brassica campestris L., respectively. Investigations on the temperature response of plant in the development of flower organs are in progress. Transformation system in B.campestris was also studied to obtain transgenic plants. We could select promisable strains which had high regeneration ability and strong resistance to antibiotics. Less