中国农业科学2012，Vol.45Issue(18)：3883-3891,9.DOI:10.3864/j.issn.0578-1752.2012.18.021
山东小麦品种更替过程中光合特性的演变
Evolution in Photosynthetic Characteristics of Wheat Cultivars Widely Planted in Shandong Province Since 1950s
摘要
Abstract
[Objective] The evolution in photosynthetic characteristics of historical wheat cultivars was investigated in order to understand the main yield-limiting factors and guide future breeding strategies for improving light use efficiency. [Method] Changes in grain yield, harvest index (HI) and photosynthetic parameters of eight landmark wheat cuitivars widely planted in Shandong province in different years since 1950s were investigated in the fields. [Result] The grain yield and HI showed a significant linear improvement in Shandong province with the cultivars changed, however, the biomass did not increase obviously. The chlorophyll content (Chl a and Chl b), net photosynthetic rate (Pn), stomatal conductance (Gs), carboxylation efficiency (CE), photochemical efficiency (ΦPSn) of photosystem Ⅱ (PS Ⅱ), and respiratory rate ? of flag leaves from all historical cultivars reached their maximal values between flowering date and 10 days after anthesis (DAA), then declined gradually, and the reduced rate of varieties after 1980 was less than the varieties before 1980. The intercellular CO2 concentration (Ci) and the non-photochemical quenching (NPQ) increased persistently after the flag leaves were full expanded. The decrease of Pn was not caused by stomatal factors. The carboxylase activity of ribulose bisphosphate carboxylase oxygenase (Rubisco) was crucial for the earlier reduction of Pn after flowering rather than chlorophyll content, while the chlorophyll degradation, ΦpSⅡ and NPQ played important roles in further reduction at the late duration of grain filling. The photosynthetic characteristics improved with the cultivar evolution derived from both the increase in chlorophyll content, Pn, Gs, CE and ΦPSⅡ and their longer duration, and which may be the physiological basis of the grain yield improvement. However, the respiratory rate also enhanced with the cultivar change and which was disadvantage to yield increase. [ Conclusion] Improved photosynthetic characteristics and lengthened duration played important roles in genetic gain in grain yield of Shandong wheat. The HI of Shandong wheat can be improved further, while it should be independent of plant height reduction. The future breeding for yield increase through improving light use efficiency should take all steps involved in photosynthesis as a whole.关键词
小麦/品种演变/光合特性/籽粒产量/遗传改良Key words
wheat/ cultivar evolution/ photosynthetic characteristics/ grain yield/ genetic improvement引用本文复制引用
彭芹,郭骞欢,张西斌,程敦公,戴双,李豪圣,赵世杰,宋健民..山东小麦品种更替过程中光合特性的演变[J].中国农业科学,2012,45(18):3883-3891,9.基金项目
国家重点基础研究发展计划(2009CB118505)、国家自然科学基金(31171551,31271635)、现代农业产业体系建设专项(CARS-03-1-8)、转基因生物新品种培育科技重大专项(2011ZX08002-003)、作物生物学国家重点实验室开放课题资助项目 （2009CB118505）
