元江普通野生稻渗入系籽粒镉评价及与农艺性状的相关性分析

Cd accumulation in grains of introgression lines of Yuanjiang common wild rice and its correlation with agronomic traits in rice

为探讨云南普通野生稻渗入系籽粒积累镉的能力,并分析其籽粒镉含量与田间农艺性状的相关性,于2019年3—10月在滇南某镉污染农田种植120份元江普通野生稻渗入系BC3F4株系,测定其籽粒镉含量,并就籽粒镉含量与渗入系材料主要农艺性状展开相关性研究。结果表明:120份渗入系材料籽粒镉含量差异极显著,籽粒镉含量在0.05~3.57 mg·kg^(-1)范围内,存在广泛的遗传多样性,从中筛选出镉低积累材料54份,高积累材料3份。120份渗入系材料含3种水稻类型(籼稻、粳稻及彩色稻),3种水稻类型籽粒镉含量在种内差异显著,变异系数大;在种间,籽粒镉含量彩色稻与籼稻、粳稻间均存在显著差异,而籼稻与粳稻间差异不显著。籽粒镉含量与渗入系株系产量及结实率间存在正相关性,相关系数分别为0.411和0.300,与其他性状无相关性。籼稻类、粳稻类产量与籽粒镉含量的相关系数分别为0.446和0.672,籼稻类、粳稻类结实率与籽粒镉含量的相关系数分别为0.362和0.634。研究表明,渗入系后代各株系间镉积累差异极显著,可从中筛选出低积累和高富集株系;渗入系株系籽粒镉含量与产量及结实率存在相关性,可作为田间判别株系镉含量的依据,并为镉积累相关基因挖掘提供理论依据。

This study aimed to evaluate the cadmium(Cd)accumulation capacity of Yunnan common wild rice by investigation of Cd accumulation in grains of introgression lines of Yuanjiang common wild rice and to explore the relationship between the Cd content in the grains and the main agronomic traits of rice.A total of 120 BC3F4 strains of Yuanjiang wild rice introgression lines were planted in a Cdcontaminated farmland in southern Yunnan from March to October in 2019.We detected the Cd content in the grains,evaluated the main agronomic traits,and also conducted a correlation analysis between them.The results were as follows:the minimum and maximum Cd accumulation in the 120 introgression lines were 0.05 mg·kg^(-1) and 3.57 mg·kg^(-1),respectively,indicating an extensive genetic diversity in Cd uptake in the grains of the introgression line progeny.Fifty-four low-Cd accumulation and three high-Cd-accumulation strains were screened from the 120 introgression lines.The 120 introgression lines were divided into three types,including indica,japonica,and colored rice.Each rice type exhibited a substantial difference in the Cd content in the grains with large variation coefficients.The Cd content in the grains of colored rice was significantly different from those of indica and japonica rice,whereas no significant difference could be detected between the indica and japonica rice.The Cd content in the grains positively correlated with rice yield and seed setting rate with correlation coefficients of 0.411 and 0.300,respectively,and no correlation with other traits.The correlation coefficients between the grain Cd content and indica and japonica yields were 0.446 and 0.672,respectively,and the correlation coefficients between the grain Cd content and seed setting rate of indica and japonica were 0.362 and 0.634,respectively.The Cd accumulation difference among the strains of the introgression lines was very significant,and low and high accumulation lines could be selected from them.We observed a correlation between the Cd content in the seeds of the introgression lines and the yield and seed setting rate,which could be used as a basis for the field identification of the Cd content in the lines and to provide a theoretical basis for mining Cd accumulation-related genes.