【目的】揭示土壤水分亏缺条件下节水抗旱稻根系的形态和生理指标的变化规律,阐明其节水抗旱的特异性生理基础。【方法】2015和2016年利用盆栽试验,以节水抗旱稻旱优113号(HY113)和高产水稻扬两优6号(YLY6)为试验材料,通过设置淹灌(对照...【目的】揭示土壤水分亏缺条件下节水抗旱稻根系的形态和生理指标的变化规律,阐明其节水抗旱的特异性生理基础。【方法】2015和2016年利用盆栽试验,以节水抗旱稻旱优113号(HY113)和高产水稻扬两优6号(YLY6)为试验材料,通过设置淹灌(对照)和干旱(土壤水势-38 k Pa左右)处理,研究干旱对节水抗旱稻与高产水稻根系形态结构和生理指标的影响及其与地上部生物量积累的关系。【结果】与淹灌相比,干旱处理显著降低了两个水稻品种的地上、地下干物质积累量,同时显著降低了节水抗旱稻HY113的根冠比(由0.18降为0.12),高产水稻YLY6的根冠比无显著变化。干旱处理下,两个品种的水稻根系活力均显著增加,但HY113的增加幅度显著高于YLY6,乳熟期HY113在2015和2016两年的平均增幅为38.7%,而YLY6为22.8%,其中2015年乳熟期HY113的根系活力从86μg·g^(-1)·h^(-1)增加至174μg·g^(-1)·h^(-1)。干旱处理下,HY113和YLY6的根系吸收面积均显著减小,但HY113的减小幅度显著低于YLY6。与高产水稻YLY6相比,节水抗旱稻HY113的根数、根体积和根干重均较少,总干物质积累量较少,但其根系活力和根系有效吸收面积较大。【结论】节水抗旱稻HY113具有根量少,但根系吸收效率高的特点,其在缺水条件下能维持较高的根系活力和根系吸收面积;在遭遇水分亏缺时HY113可通过减小根冠比,使得更多的干物质留在地上部分以保证籽粒产量。展开更多
Recent studies revealed that DNA methylation plays an important role in plant growth and development. In this study, a water-saving and drought-resistant rice variety Huhan 3 was subjected to drought stress from tille...Recent studies revealed that DNA methylation plays an important role in plant growth and development. In this study, a water-saving and drought-resistant rice variety Huhan 3 was subjected to drought stress from tillering to grain-filling stages in six successive growth cycles. The variations in DNA methylation pattern between the original generation （Go） and the sixth generation （G6） were analyzed by using methylation sensitive amplification polymorphism method. The results revealed that the methylated loci accounted for 34.3% to 34.8% of the total loci. Among these methylated loci, 83.1% to 84.8% were full- and hyper-methylated and 15.2% to 16.9% were hemi-methylated. The DNA methylation level decreased from the three-leaf to four-leaf stages in Huhan 3. Differentially methylated loci （DML） between generations or/and between different developmental stages accounted for 4.0% of the total loci, most of which were only related to plant development （57.9%）. Compared to Go, the DNA methylation pattern of G8 changed after drought domestication, at the three-leaf stage, de-methylation accounting for 59.1%, while at the four-leaf stage, re-methylation for 47.9%. Genome-wide alternations of DNA methylation were observed between the two seedling stages, and DML mainly occurred on the gene＇s promoter and exon region. The genes related to DML involved in a wide range of functional biology and participated in many important biological processes.展开更多
文摘【目的】揭示土壤水分亏缺条件下节水抗旱稻根系的形态和生理指标的变化规律,阐明其节水抗旱的特异性生理基础。【方法】2015和2016年利用盆栽试验,以节水抗旱稻旱优113号(HY113)和高产水稻扬两优6号(YLY6)为试验材料,通过设置淹灌(对照)和干旱(土壤水势-38 k Pa左右)处理,研究干旱对节水抗旱稻与高产水稻根系形态结构和生理指标的影响及其与地上部生物量积累的关系。【结果】与淹灌相比,干旱处理显著降低了两个水稻品种的地上、地下干物质积累量,同时显著降低了节水抗旱稻HY113的根冠比(由0.18降为0.12),高产水稻YLY6的根冠比无显著变化。干旱处理下,两个品种的水稻根系活力均显著增加,但HY113的增加幅度显著高于YLY6,乳熟期HY113在2015和2016两年的平均增幅为38.7%,而YLY6为22.8%,其中2015年乳熟期HY113的根系活力从86μg·g^(-1)·h^(-1)增加至174μg·g^(-1)·h^(-1)。干旱处理下,HY113和YLY6的根系吸收面积均显著减小,但HY113的减小幅度显著低于YLY6。与高产水稻YLY6相比,节水抗旱稻HY113的根数、根体积和根干重均较少,总干物质积累量较少,但其根系活力和根系有效吸收面积较大。【结论】节水抗旱稻HY113具有根量少,但根系吸收效率高的特点,其在缺水条件下能维持较高的根系活力和根系吸收面积;在遭遇水分亏缺时HY113可通过减小根冠比,使得更多的干物质留在地上部分以保证籽粒产量。
基金supported by the National High-Technology R&D Program of China (Grant No. 2012AA101102)the Project for High-Level Talents of China (Grant No. 2010C1120)Shanghai Key Program for Agriculture Science and Technology, China
文摘Recent studies revealed that DNA methylation plays an important role in plant growth and development. In this study, a water-saving and drought-resistant rice variety Huhan 3 was subjected to drought stress from tillering to grain-filling stages in six successive growth cycles. The variations in DNA methylation pattern between the original generation （Go） and the sixth generation （G6） were analyzed by using methylation sensitive amplification polymorphism method. The results revealed that the methylated loci accounted for 34.3% to 34.8% of the total loci. Among these methylated loci, 83.1% to 84.8% were full- and hyper-methylated and 15.2% to 16.9% were hemi-methylated. The DNA methylation level decreased from the three-leaf to four-leaf stages in Huhan 3. Differentially methylated loci （DML） between generations or/and between different developmental stages accounted for 4.0% of the total loci, most of which were only related to plant development （57.9%）. Compared to Go, the DNA methylation pattern of G8 changed after drought domestication, at the three-leaf stage, de-methylation accounting for 59.1%, while at the four-leaf stage, re-methylation for 47.9%. Genome-wide alternations of DNA methylation were observed between the two seedling stages, and DML mainly occurred on the gene＇s promoter and exon region. The genes related to DML involved in a wide range of functional biology and participated in many important biological processes.
