转Bt基因水稻的碳代谢特性

Research on Carbon Metabolism Characteristics of Transgenic Bt Rice

【目的】评价外源Bt基因导入对水稻碳代谢特性的影响。【方法】以转Bt基因水稻克螟稻1号及其非转基因亲本秀水11,以及克螟稻1号与3个杂交水稻恢复系明恢63、R3027和99亚162杂交和连续回交而育成的农艺性状和抗虫性稳定品系的3对近等基因系为材料,对叶绿素与可溶性糖含量、RuBP羧化酶、蔗糖合成酶及蔗糖磷酸合成酶活性、干物质及有机碳积累量等碳代谢指标进行了测定。【结果】分蘖盛期克螟稻1号的叶绿素a含量、可溶性糖含量、干物质和有机碳含量均极显著低于秀水11(P<0.01),叶绿素b含量、蔗糖合成酶和蔗糖磷酸合成酶活性显著低于秀水11(P<0.05),但其它3对Bt水稻与非Bt水稻间所有生理指标均无显著差异;齐穗期克螟稻1号蔗糖磷酸合成酶活性显著高于秀水11,而干物质和有机碳积累量则显著低于秀水11;BtR3027蔗糖合成酶活性显著低于R3027,而Bt99亚162可溶性糖含量和蔗糖磷酸合成酶活性则显著高于99亚162;成熟期所有Bt水稻与各自非Bt水稻间干物质重和有机碳积累量差异均不显著。【结论】克螟稻1号大多数碳代谢指标的显著变化主要是由无性系变异引起的;3对近等基因系中Bt基因对个别碳代谢指标的影响是短暂的,且与Bt基因所处的遗传背景有关。

[Objective] The objective of this study was to evaluate the effect of transgene CrylAb on carbon metabolism characteristics in rice. [Method] Transgenic Bt （CrylAb） rice KMD1 and its parent Xiushui 11, as well as three pairs of Bt and non-Bt rice near-isogenic lines which were derived from the progeny of crosses and continuous backcrosses between the KMD 1 and Minghui 63, R3027 and 99Ya162, respectively, were field grown and measured for the content of chlorophyll and soluble sugar, the activity of RuBPCase, sucrose synthetase and sucrose phosphate synthase in leaves, the dry weight and organic carbon accumulation per plant at different developmental stages. [Result] At tillering stage, KMD 1 had significant lower contents of chlorophyll a, chlorophyll b and soluble sugar, lower activities of sucrose synthetase and sucrose phosphate synthase, and lower dry weight and organic carbon accumulation than those of Xiushui 11, but no significant differences between other 3 pairs of Bt and non-Bt rice lines were observed in all physiological indexes tested. At full heading stage, the activity of sucrose phosphate synthase of KMD 1 was significantly higher than that of Xiushui l 1, although its dry weight and organic carbon accumulation were significantly lower, while Bt R3027 showed a significant lower sucrose synthetase activity and Bt 99Ya162 showed significant higher soluble sugar content and sucrose phosphate synthase activity than the non-Bt type, respectively. At maturity stare, no si~,nificant difference~ ware.found in dry weight and organic carbon accumulation in four pairs of Bt and non-Bt rice lines. [ Conclusion ] Significant change of most physiological indexes related to carbon metabolism in transgenic rice KMD 1 was resulted from somaclonal variations, while the effect of CrylAb gene on individual index in other 3 pairs of Bt and non-Bt rice near-isogenic lines was transitory and related to the genetic background of Bt gene incorporation.