摘要
【目的】研究花期前后高温胁迫对不同耐热性玉米光合特性及产量品质的影响。【方法】以耐热基因型浚单20和热敏感基因型驻玉309为材料,分别于花前(吐丝前0—8 d)和花后(吐丝后0—8 d)进行高温处理,测定叶片的叶绿素相对含量(SPAD)、光合及叶绿素荧光参数、磷酸烯醇式丙酮酸羧化酶(PEPCase)和核酮糖二磷酸羧化酶(RuBPCase)活性及籽粒的产量和品质。【结果】花期前后高温胁迫导致2个基因型玉米产量显著下降,浚单20产量下降幅度小于驻玉309,且花后高温处理影响大于花前处理;高温处理降低了穗位叶净光合速率(Pn)、气孔导度(Gs)、最大光化学效率(Fv/Fm)、光量子产量(ΦPSII)、光化学猝灭系数(qP)、磷酸烯醇式丙酮酸羧化酶(PEPCase)和核酮糖二磷酸羧化酶(RuBPCase)活性,提高了细胞间隙CO2浓度(Ci)和非光化学猝灭系数(qN)。【结论】花期前后高温胁迫对玉米的光合有显著影响,导致玉米产量显著降低,品质受到显著影响。高温胁迫下耐热玉米基因型比热敏感玉米基因型具有较高的叶绿素含量和光合能力,产量和品质受高温影响较小。
[Objective] The objective of this study was to identify exogenous spermidine on photosynthesis and chlorophyll fluorescence under high temperature treatments during flowering （0-8 d before silking and 0-8 d after silking）. [Method] The heat-tolerant maize genotype XD20 and heat-sensitive maize genotype ZY309 were used in this study. Photosynthetic parameters, chlorophyll fluorescence variation, the activities of ribulose-1,5-bi-sphosphate carboxylase （PEPCase） and phosphoenolpyrovate carboxylase （RuBPCase） were investigated during flowering, [Result] The results showed that the heat-sensitive genotype got a significant reduction in grain yield with a more reduction rate under the treatment after flowering than before flowering. It was less affected for heat-tolerant genotype. SPAD, net photosynthetic rate （Pn）, stomatal conductance （Gs）, primarily photochemical efficiency （Fv/Fm）, actual photochemical efficiency （~PSII）, photochemical quenching （qP）, PEPCase and RuBPCase activities of ear-leaves were reduced. But intercellular CO2 concentration （Ci）, non-photochemical quenching （qN） were increased. [ Conclusion ] The results showed that there were significant effects of high temperature treatments during flowering on photosynthetic characteristics of summer maize, and the yield were significantly decreased. The heat-tolerant maize genotype has more photosynthesizing capacity and chlorophyll content than the heat-sensitive maize genotype.
出处
《中国农业科学》
CAS
CSCD
北大核心
2012年第23期4947-4958,共12页
Scientia Agricultura Sinica
基金
国家玉米产业技术体系专项资金(NYCYTX-02)
河南省重大公益性项目(091100910100)
国家公益性行业(气象)科研专项(GYHY201006041)
关键词
玉米
基因型
高温
产量
品质
光合特性
maize
genotype
high temperature
yield
quality
photosynthetic characteristics
