在大田栽培条件下,以高蛋白花生品种KB008、高脂肪品种花17(H17)和高油酸/亚油酸(O/L)品种农大818(818)为试验材料,研究了3种类型花生品种籽仁中蛋白质、脂肪含量及与品质合成相关的碳、氮代谢酶活性差异.结果表明:KB008的蛋白质含量显著高于H17和818,而可溶性糖含量和O/L值显著低于其他两品种.KB008籽仁中氨基酸组分含量均高于其他两品种,特别是谷氨酸和赖氨酸含量显著高于后两者;油酸含量显著低于、而亚油酸含量显著高于其他两品种.3种类型花生在整个生育期中叶片的硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、谷氨酸脱氢酶(GDH)、谷氨酸合成酶(GOGAT)和谷丙转氨酶(GPT)活性均以KB008最高,其次为H17.3种类型花生在结荚期的叶片磷酸烯醇式丙酮酸羧化酶(PEPCase)和1,5-二磷酸核酮糖羧化酶(RuBPCase)活性大小均表现为KB008〉H17〉818,说明较高的PEPCase和RuBPCase活性有利于蛋白质合成与积累.叶片中蔗糖合成酶(SS)活性大小表现为H17〉818〉KB008,KB008的磷酸蔗糖合成酶(SPS)活性显著低于其他两品种,而H17的SPS活性在花后60d时仍保持较高活性,说明较高的叶片SPS、SS活性有利于花生籽仁脂肪的形成.
Taking high-protein peanut cultivar KB008,high-fat peanut cultivar Hua17(H17),and high-oleic acid/linoleic acid(O/L) peanut cultivar Nongda818 as test materials,a field experiment was conducted in 2010 and 2011 to study the differences in the contents of protein,fat,and their components of the seed kernels,and the differences in the activities of the carbon and nitrogen metabolism enzymes related to the quality synthesis in the blades.As compared with that of H17 and Nongda818,the seed kernel of KB008 had significantly higher protein content but significantly lower soluble sugar content and O/L ratio,and the contents of the amino acid components,especially glutamic acid and lysine,in the seed kernel of KB008 were significantly higher.During the whole growth period,the activities of nitrate reductase(NR),glutamine synthetase(GS),glutamate dehydrogenase(GDH),glutamate synthase(GOGAT),and glutamate pyruvate transaminase(GPT) in the blades of the three cultivars were in the order of KB008H17 Nongda818.At pod setting stage,the activities of PEPCase and RuBPCase in the blades of the three cultivars were ranked as KB008H17 Nongda818.The higher PEPCase and RuBPCase activities of KB008 facilitated the protein synthesis and accumulation.The sucrose synthase(SS) activity in the blades was in the order of H17 Nongda818KB008.The sucrose phosphate synthase(SPS) activity of KB008's blades was significantly lower than that of the other two cultivars,while the SPS activity of H17's blades was still higher even in the 60 days after anthesis,suggesting that the higher activities of SS and SPS in the blades were in favor of the fat formation in peanut seed kernel.