Preliminary Study on Photochemical Activities in Chloroplasts of Flag Leaf Sheathes for Super Hybrid Rice Liangyoupeijiu

By using a super high-yielding hybrid rice combination Liangyoupeijiu,its male parent 9311,female parent Pei'ai 64S and a three-line hybrid rice combination Shanyou 63 as experimental materials,the techniques of an artificial reaction system for photosynthetic membrane,and 32Pi isotopic labeling and so on,were used to study the photochemical activities of the flag leaf sheathes for Liangyoupeijiu.The means of PS Ⅰ reducing capacity of the flag leaf sheathes and blades for Liangyoupeijiu were 6.35 and 15.31 μmol/(mg·h)higher than those for Shanyou 63,respectively;the means of PSⅡoxygen release activities of flag leaf sheathes and blades for Liangyoupeijiu were 6.16 and 9.89 μmol/(mg·h)higher than those for shanyou 63 respectively,the calcium contents in extracts,the Mg2+-ATPase activities on the chloroplast membranes,the cyclic photophosphorylation activities of the flag leaf sheathes and blades for Liangyoupeijiu were also higher than those for Shanyou 63;the means of noncyclic photophosphorylation activities of the flag leaf sheathes and blades for Liangyoupeijiu were 0.25 and 0.31 μmol/(mg·h)higher than those for Shanyou 63,respectively;the photochemical avtivities of the flag leaf sheathes and blades for Liangyoupeijiu were significantly higher than those of its parents at most stages,showing heterosis over mid-parent or heterobeltiosis.It suggested that rice flag leaf sheath had completely the same kind of the photochemical activity characters as rice flag leaf blade with quantitative differences.High photochemical activities of the flag leaf sheath for Liangyoupeijiu may be one of the important reasons that Liangyoupeijiu performed super high-yielding property.