Impacts of Ozone Stress on Dry Matter Accumulation and Distribution of Rice Genotypes with Different Ozone Sensitivity
SHAO Zaisheng;MU Hairong;ZHAO Yipeng;PENG Bin;WANG Yulong;WANG Yunxia;YANG Lianxin;Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops , Yangzhou University;Xuzhou Institute of Agricultural Sciences of the Xuhuai District of Jiangsu Province;College of Environmental Science and Engineering , Yangzhou University;
【Objective】The dry matter accumulation and distribution of rice with different ozone sensitivity in response to ozone stress were studied in order to provide reference for ozone-tolerant rice breeding.【Method】Twenty-three rice cultivars or lines were grown in glasshouse-type fumigation chambers with low ozone concentration as control(C-O3, 10 n L/L) and high ozone concentration as elevated O3 treatment(E-O3, 100 n L/L) from a week after transplanting until maturity. The effects of ozone stress on dry matter accumulation and distribution of rice genotypes were determined, as well as the relationships between their responses to ozone stress and the ozone-induced changes in the above-ground biomass at maturity stage. Based on the ozone-induced changes in the above-ground dry weight, these rice genotypes were clustered into three types by the MinS Sw(dynamic clustering method-minimum sum of squares within groups) method.【Result】Compared to the control, ozone stress decreased the above-ground dry weight of three rice types A, B and C at maturity by 19%, 39% and 52%, respectively, and significant treatment effects were detected in B and C. Ozone stress slightly increased the leaf dry weight of rice type A, but significantly decreased that of B(-11%) and C(-25%). Ozone stress significantly decreased stem dry weight by 26%, 41% and 57%, panicle dry weight by 34%, 59% and 62% of rice types A, B and C, respectively. Ozone stress significantly increased the ratio of leaf to above-ground dry weight(+46%), but significantly decreased that of stem(-8%) and panicle(-24%). Ozone level and rice eype interacted with the measured parameters to various degress, which gave rise to small changes in rice type A compared to type B and C.【Conclusion】The above results indicated that, ozone concentration of 100 n L/L seriously inhibited the growth of rice organs, decreased assimilates allocation to stems and panicles, but greatly increased assimilates allocation to leaves, resulted in the decrease of mechanical strength of rice stems. In general, these ozone-induced changes in ozone-sensitive rice genotypes were more obvious than those in ozone-resistant rice types.
【Fund】： 国家自然科学基金面上项目(31371563和31471437);; 江苏省自然科学基金资助项目(BK20151298和BK20161161);; 江苏省普通高校研究生科研创新计划资助项目(XKYCX17_053)
【CateGory Index】： S511;X515
【CateGory Index】： S511;X515