转反义Waxy基因改良龙特甫雄性不育系品质及其育种应用

Quality Improvement of Long-te-fu Male Sterile Lines with Antisense Wx Gene and Associated Application in Rice Breeding

通过转反义Wx基因育成了直链淀粉含量(AC)降低的籼稻龙特甫新保持系B(wxLB1,wxLB2),并转育成了相应的新不育系新龙保A1(wxLA1)和新龙保A2(wxLA2)。考察和测定了由新不育系和原不育系与恢复系配制的杂种F1代的农艺性状、直链淀粉含量、胶稠度及RVA谱。结果表明:由wxLA1,A2配制的杂种后代直链淀粉含量和粒重极显著地低于各自对照(CK1:LA/YH559,CK2:LA/MH63),胶稠度(GC)和崩解值(BDV)则明显高于对照,并达到极显著水平。而冷胶黏度(CPV)、消减值(SBV)、峰值时间(PeT)、起浆温度(PaT)和回复值(CSV)则显著或极显著低于对照。杂种后代淀粉胶稠度和RVA特征值变异来源分析显示,GC和RVA谱特征值主要受母本影响,且都达到极显著水平。综合结果表明,选择改良籼稻龙特甫雄性不育系品质是改善杂交稻米淀粉理化和蒸煮品质的有效途径。

In this study, we have generated the Long-te-fu new maintain lines B （wxLB1, wxLB2） with the low amylose content （AC） in seeds of these lines by trans-antisense Wx gene, and obtained the corresponding new male sterile lines of Xin-long-bao A （wxLA1, wxLA2） by transferring breeding. The agronomic traits, amylose content, gel consistency （GC） and the RVA profile eigenvalue of hybrid offspring by the new sterile lines and the original male sterile lines crossed with restorers respectively were tested, the results showed that the amylose content and grain weight were extremely significant lower than the respective control, the gel consistency （GC） and breakdown viscosity （BDV） were higher than the respective control obviously, and reached the extremely significant level. And the cold viscosity （CPV）, setback （SBV）, peak time （PeT）, pasting temperature （PaT） and consistence （CSV） were significant or extremely significant lower than the respective control. The analysis of variation source on gel consistency and RVA eigenvalue of hybrid offspring indicated that starch GC and the RVA eigenvalue mainly affected by the female parent and both reached to the extremely significant level. The integrative results showed that the improvement quality of the male sterile lines of Long-te-fu was an effective way to meliorate the starch physico-chemical and cooking quality of hybrid in indica rice.