木薯不同品种(系)生物积累量特性及其与淀粉积累关键基因表达相关性研究

Characterization of biomass and expression of genes involved in starch accumulation among different cassava varieties (lines)

以11个木薯品种(系)(SC205、SC5、SC8、Arg7、Rayong9、KU50、9I、R3、17Q、FB-1、FB-4)为材料,采用田间统计分析,实时定量PCR和皮尔森相关分析,对不同木薯品种(系)的生物积累量特性、淀粉积累关键基因的表达及两者之间的相关性进行分析。结果表明,品种(系)间在叶绿素含量、净光合速率、干物质积累率及相关途径重要基因表达水平上均存在显著差异。其中:块根产量高的品种或品系FB-1、SC5、SC8、KU50、SC205、Rayong9在块根成熟期保持较高的干物质积累量;而对于叶片叶绿素含量和净光合速率,SC205保持最高,品种(系)间存在差异(P<0.05),但与产量没有明显相关性;块根膨大期叶片净光合速率最高,且与叶绿素含量呈显著正相关。基因表达与产量性状的相关分析表明,块根形成期MeAGPS1的表达量及块根形成期和膨大期MeGBSS1的表达量与块根膨大期木薯块根的干物质率呈显著正相关,块根成熟期MeSBE2.2的表达量与块根成熟期木薯块根的干物质率呈显著正相关。

Biomass accumulation and expression of genes involved in starch accumulation in 11 different cassava varieties （lines） including SC205, SC5, SC8, Arg7, Rayongg, KU50,91, R3, 17Q, FB- 1 and FB-4 were used to study the characteristics of biomass accumulation and the correlation between them by the means of field test and statistical analysis, quantitative real-time PCR and Pearson correlation coefficient analysis. The results showed that;the chlorophyll content,net photosynthesis ratio, dry matter content of storage root and expression level of tested genes at three developing stages exhibited significant difference among various varieties （lines）; FB- 1, SC5, SC8, KU50, SC205 and Rayong9 displayed higher bioaccumulation and storage root yields at tuberous root mature stage; The chlorophyll content reached its peak and displayed significantly positive correlation with net photosynthesis ratio at enlargement stage,but no significant correlation with yield and other physiological index. Correlation analysis indicated that the expression leve~ of MeAGPSI （ formation stage） and MeGBSS1 （formation and enlargement stage） have significantly positive correlation with the dry matter content of storage root （enlargement stage）, and the expression revel of MeSBE2.2 has significantly positive correlation with the dry matter content of storage root in mature stage.