摘要：
[Objective]In order to provide reference for developing cassava leaves as feed resources,nutritional compo-nents in leaves of cassava wild species and cultivars were studied. [Method]Nutritional components including crude lipid, crude protein,soluble sugar,starch,carotenoid and HCN contents in functional leaves of eight cassava germplasms (three cassava wild species and five cultivars) were determined. The expression levels of proteases(UGPase、AGPase、GBSSI and Linamarase) were determined using Western blotting method. [Result]Among eight cassava germplasms, wild species Mani-hot cecropiaefolia Phhl contained the highest starch content in functional leaves, which was 2.5 g/100 gDW, the highest sol-uble sugar content which was 30.0 g/100 gDW and the highest carotenoid content which wsa 91.9 mg/100 gFW, but protein and hydrocyanic acid contents were at moderate level. Cultivar SC9 contained moderate protein and soluble sugar contents in functional leaves, and the lowest HCN content which was 167 mg/kgFW. According to Western blotting analysis, expression levels of key enzymes, UGPase,AGPase and GBSSI, for sugar and starch metabolic pathway were the highest in M. cecropi-aefolia Phhl;while key enzyme Linamarase for SC9 HCN metabolic pathway was the lowest. Expression levels of all proteins were in accordance with related physiological indexes variation trend. Principal component analysis revealed that, the cassa-va germplasms with high starch and soluble sugar content in leaf were tend to contain low crude lipid content;and the ones with high soluble sugar, crude protein and carotenoid contents would contain low HCN content. [Conclusion]Comprehensive nutritional value of functional leaves in cassava wild species M. cecropiaefolia Phhl is high,which may be developed as feed resources for livestock and silkworm. HCN content in cultivar SC9 fresh leaf is low,thus it can be used as feed for silkworm.%[目的]研究不同木薯种质叶片的营养成分差异,为木薯叶作为饲料资源开发利用提供参考.[方法]测定8个木薯种质(3个野生种和5个栽培种)功能叶片的粗脂肪、粗蛋白、可溶性糖、淀粉、类胡萝卜素和氢氰酸(HCN)含量,并利用Western blotting测定功能叶片相关蛋白酶(UGPase、AGPase、GBSSI和Linamarase)的表达水平.[结果]8个木薯种质中,野生种Manihotcecropiaefolia Phhl功能叶片的淀粉、可溶性糖和类胡萝卜含量最高,分别为2.5 g/100 gDW、30.0 g/100 gDW和91.9 mg/100 gFW,蛋白质和HCN含量中等;栽培种SC9功能叶片蛋白质和可溶性糖含量中等,HCN含量最低,仅167 mg/kgFW.Western blotting分析结果表明,M.cecropiaefoliaPhhl叶片糖和淀粉代谢通路的关键酶UGPase、AGPase和GBSSI表达水平最高,SC9 HCN代谢通路的关键酶Linamarase表达水平最低,各蛋白质表达水平与相关生理指标变化趋势一致.通过主成分分析结果可看出,叶片淀粉和可溶性糖含量较高的木薯种质,粗脂肪含量较低;可溶性糖、粗蛋白和类胡萝卜素含量较高的木薯种质,HCN含量较低.[结论]野生木薯M.cecropiaefolia Phhl完全展开功能叶片的综合营养价值较高,可考虑作为畜禽和蚕用饲料资源开发利用;栽培种木薯SC9新鲜叶片HCN含量较低,也可优先作为蚕用饲料.
