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对超级玉米杂交种的选育与推广的思考 总被引:7,自引:2,他引:7
Super maize was a science and technology innovation for enhancing maize cultivars yield ability on the basis of maize heterosis utilization at present.This paper discussed the significance of super maize breeding,indicating that the objective of super maize should consider the approved efficiency of cultivar,the character of high yield and stable yield and the determination of yield index in high yield tackling field,except"super high yield,high-quality,multi-resistant,wide-suitable,easy production of seed",also proposed higher requirements for germplasm-innovation,plant type selection and plant characters.Aiming at present status of super maize popularization,suggesting that we should accelerate to establish reginal trial appoved criteria,pay attention to finy varieties with suitable cultivation method,high-yield demonstration and high-yield tackling trial. 相似文献
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超高产夏玉米花粒期不同部位叶片衰老与抗氧化酶特性 总被引:3,自引:0,他引:3
为探讨超高产玉米叶源衰老特征, 揭示其抗氧化关键酶及膜脂过氧化特性, 为玉米衰老调控和高产栽培提供依据, 本研究在大田条件下, 以我国创高产纪录的夏玉米为例, 从单株水平上对高产纪录试验(EHYR)和普通生产田(MCFF)玉米叶片衰老及抗氧化酶特性比较表明, EHYR产量达19 349 kg hm-2, 是MCFF的2.28倍。MCFF和EHYR叶片分别在开花后30 d和50 d进入速衰期, MCFF叶片衰老比EHYR提前20 d;速衰期EHYR叶面积降幅比MCFF低5.7%。EHYR在籽粒灌浆后期, 中上部叶片净光合速率较高, 可溶性蛋白含量明显高于MCFF, 而MDA含量则维持较低水平。在叶片衰老过程中, 自开花后20 d开始, EHYR上部和中部叶片SOD活性较高, 下部叶片则以SOD、POD和CAT三者活性较高;MCFF仅中部叶片POD和CAT活性较高。EHYR叶片衰老程度与CAT活性极显著负相关, MCFF叶片衰老与SOD和POD活性显著负相关, 且二者叶片衰老进程中SOD、POD、CAT的直接作用大于间接作用。与MCFF相比, EHYR叶片除具较高SOD和POD活性外, 在籽粒灌浆后期同时保持较高CAT活性和可溶性蛋白含量是降低膜脂过氧化程度, 延缓叶片衰老的重要原因。开花后20 d是EHYR与MCFF叶片衰老出现差异的生理临界点, 因而在此时期之前调控更有利于延缓衰老。 相似文献
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