玉米光温敏雄性不育系CB1208-82的生理生化代谢研究

自交系"CB1208-82"是浙江大学新发现的玉米光温敏雄性不育材料,探究其雄性不育的生理生化机制,测定其不育株/可育株在雄穗不同发育时期叶片中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)的活性和O~(2-)产生速率、丙二醛(MDA)、过氧化氢(H_2O_2)、叶绿素、可溶性糖和游离脯氨酸含量。结果表明,从整体上看,不育株叶片中的抗氧化酶活性总是低于同期可育株,并且不育株叶片中的MDA和H_2O_2含量、O~(2-)产生速率高于同期可育株,说明叶片中抗氧化酶活性低、活性氧积累多可能是引起雄性不育的原因之一。不育株叶片中的叶绿素、脯氨酸和可溶性糖的含量均低于同时期的可育株,特别是在雄穗发育初期可溶性糖含量显著低于可育株,说明光合效率低及营养物质缺乏可能会导致雄穗发育异常。

Physiological and Biochemical Metabolism Studies on the Photo-thermo-sensitive Male Sterile Line of Maize CB1208-82

Using photo-thermo-sensitive male sterile line in hybrid seed production is an important way to achieve heterosis. The photo-thermo-sensitive male sterile line "CB1208-82" was newly discovered in Zhejiang University. In order to explore the physiological and biochemical mechanism for male sterility, the activity of superoxide dismutase(SOD), catalase(CAT), peroxidase(POD) and ascorbate peroxidase(APX), the production rate of O₂^-, the contents of malondialdehyde, H₂O₂, chlorophyll, soluble sugars and free proline in leaves at different stages of male ear development were determined and analyzed. The results showed that, as a whole, the antioxidant enzyme activity in the leaves of sterile plants was always lower than that of fertile plants at the same period. The content of MDA, H₂O₂ and the production rate of O₂^- in the leaves of the sterile plants were higher than those of fertile plants at the same period. It is suggested that the low activity of antioxidant enzymes in the sterile plant leaves and the accumulation of active oxygen may be the reasons for male infertility. The contents of chlorophyll, proline and soluble sugar in the leaves of the sterile plants were lower than those of the fertile plants at the same stage, especially in the early period of the male ear development, the soluble sugar content was significantly lower than that of the fertile plants, which indicated that the low photosynthetic efficiency and the lack of nutrient substance might lead to the abnormal development of the male ear.