作物学报2018，Vol.44Issue(4)：581-590,10.DOI:10.3724/SP.J.1006.2018.00581
穗分化期外施24-表油菜素内酯(EBR)促进水稻源、库及籽粒灌浆的生理机制
Physiological Mechanisms of Promoting Source, Sink, and Grain Filling by 24-Epibrassinolide (EBR) Applied at Panicle Initiation Stage of Rice
摘要
Abstract
Grain weight and yield of rice are clearly related to grain filling ability, which is strongly affected by source and sink. Studies of Brassinosteroids' effects on growth, development and yield of rice have been reported. In order to further set forth the relative physiological characteristics and relationship, we set up field experiments to study the impacts of 24-epibrassinolid (EBR) sprayed at the panicle initiation stage of Nipponbare on source capacity, sink size, sink activity and grain filling. Both T1 (0.2 μmol L–1EBR) and T2 (1 μmol L–1EBR) treatments increased the source capacity by improving the accumulation of photosyn-thate and its translocation during grain filling stage. Both EBR treatments increased the sink size through different manners: T1 treatment increased the grain weight markedly but had little influence on panicle and grain amounts; and T2 treatment signifi-cantly increased number of panicles and grains per panicle whereas had little influence on grain weight. Two EBR treatments en-hanced the sucrose lyase activity in both superior and inferior grains, especially for the activity of Acid Invertase (AI) in inferior grains. AI accelerated the transportation of photosynthate and the synthesis of starch in inferior grains. T1 and T2 significantly increased rice yield by an average of 5.6% and 15.2%, respectively, with 9.1% more in T2 than in T1. Therefore, compared with grain weight enhancement in T1, the increase of panicle and grain numbers in T2 had greater impact on rice yield. In summary, two EBR treatments at panicle differentiation stage can increase the source capacity, sink size and sink activity of rice, and then promote photosynthates accumulation and distribution, which is beneficial to grain filling. On the basis of sufficient photosyn-thates and strong sink activity, sink size enlargement can significantly increase the rice yield.关键词
水稻/源强/库容/库活性/籽粒灌浆Key words
rice/source capacity/sink size/sink activity/grain filling引用本文复制引用
李赞堂,王士银,姜雯宇,张帅,张少斌,徐江..穗分化期外施24-表油菜素内酯(EBR)促进水稻源、库及籽粒灌浆的生理机制[J].作物学报,2018,44(4):581-590,10.基金项目
本研究由国家自然科学基金项目(31571589,31071351),国家重点基础研究发展计划(973计划)项目(2015CB150401)和中国农业科学院创新工程项目资助.This work was supported by the National Natural Science Foundation of China(31571589,31071351),the National Basic Research Program of China(973 Program,grant No.2015CB150401),and the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS). （31571589,31071351）
