同源四倍体和二倍体水稻Wx基因与淀粉品质的遗传关系

用Wx 基因的(CT)n微卫星标记和切割的扩增产物多态性序列(cleaved amplified polymorphic sequence, CAPS)分子标记PCR Acc Ⅰ 对40份同源四倍体和14份二倍体水稻Wx基因型进行研究。利用484/485引物检测，Wx基因呈 Wx1、Wx2和Wx3 3种多态性；而用PCR Acc Ⅰ检测，Wx基因表现为G 型和T 型。同时，在测定稻米直链淀粉含量（AC）、胶稠度（GC）和糊化温度（GT）的基础上探讨它们与Wx基因的关系，结果表明AC、GC与Wx基因密切相关，GT与Wx基因相关不显著。综合分析表明，同源四倍体水稻中，92.0%的Wx1基因型材料为G 型，而Wx2基因型村料和800%的Wx3基因型材料为T 型。统计分析表明，Wx基因(CT)n微卫星标记检测与PCR Acc Ⅰ 分子标记检测的相关系数为0842，呈极显著正相关。

Genetic Relationships Between Wx Gene and Starch Quality in Autotetraploid and Diploid Rice

Wx genotypes of 40 autotetraploid rice and 14 diploid rice were tested by using the(CT)n microsatellite marker and a cleaved amplified polymorphic sequence(CAPS)molecular marker named PCR-Acc Ⅰ.Three microsatellite alleles were produced,i.e.Wx1,Wx2 and Wx3 in both autotetraploid and diploid rice.Comparatively,PCR-Acc Ⅰ molecular marker produced two genotypes,G-type and T-type for both autotetraploid and diploid rice.Analysis on relationship between amylose content(AC),gel consistency(GC)and gelatinization temperature(GT)of rice and Wx alleles showed that both AC and!GC were closely related to Wx genotypes,i.e.the materials with Wx1 genotype and G-type of Wx gene had higher AC and hasder GC,however,the materials with Wx2,Wx3 genotypes and T-type of Wx gene had lower AC and softer GC.On the other hand,GT was not significantly correlated with AC and Wx genotype,indicating that AC and GC of rice grain were probably controlled by Wx gene or other gene whose location was strictly linked to Wx gene,while GT of rice was not.Analysis by using microsatellite marker and PCR-Acc Ⅰ molecular marker showed that 92.0% of Wx1genotypes were G-type,but all Wx2and 80.0% of Wx3 genotypes were T-type in autotetraploid rice.The coefficient of correlation between Wx genotypes which revealed by(CT)n microsatellite marker and PCR-Acc Ⅰ molecular marker was 0.842,statistically significant at the level of 0.01.