转C_4基因水稻籽粒产量及品质分析

为了分析C_4基因导入C_3水稻后对其籽粒产量及品质的影响,以日本水稻品种‘Kitaake’(Oryza sativa L.subsp.japonica)及其转玉米PEPC、PPDK、ME基因水稻为材料,测定C_4光合酶活性、光合速率、产量以及主要营养成分。结果表明,转C_4基因水稻的4种光合酶活性显著增加,PEPC基因的导入使光合效率显著提高,与对照相比各转基因株系籽粒中水分、灰分和淀粉质量分数无显著差异,而含有PEPC基因株系的蛋白质和脂肪质量分数显著增加,可溶性糖质量分数降低。可见,PEPC基因的导入加强了籽粒中蛋白质和脂肪的积累,从而使转基因水稻千粒质量和单株穗数显著提高,这可能是转基因水稻光合生产力提高的生理生化基础。

Grain Yield and Quality Analysis of Transgenic Rice Expressing C4 Enzymes

Taking untransformed rice (Oryza sativa L. subsp.japonica) and transgenic rice with different C₄ photosynthesis genes as materials,the activity of C₄ photosynthesis enzymes and the net photosynthetic rate (P_n),the moisture,ash,fat,starch,protein and total sugar mass fraction were measured. The results showed that C₄ photosynthesis enzymes activities in different transgenic rice had high expression and P_n of PEPC transgenic rice increased significantly. The moisture,ash and starch mass fraction in the transgenic rice were similar to that of control. The protein and fat mass fraction significantly increased in PEPC transgenic rice,the PEPC,PPDK transgenic rice and the transgenic rice with PEPC,PPDK and ME genes,while the soluble sugar mass fraction was significantly lower than those of the control The PEPC gene was beneficial to protein and fat accumulation in transgenic rice,and it maybe the physiological and biochemical basis for improving photosynthetic productivity in transgenic rice expressing C₄ enzymes.