大豆根系分泌物中氨基酸组分与抗大豆胞囊线虫的相关性研究

Correlation Analysis of Amino Acids Components in Soybean Cultivars Root Exudates and Resistance to Soybean Cyst Nematode

以5种对大豆胞囊线虫(soybean cyst nematode,SCN)不同抗性的大豆品种为试材,对其根系分泌物中的氨基酸组分进行测定,并对氨基酸组分与抗大豆胞囊线虫之间的相关性进行了分析。研究结果表明:感病品种根系分泌物能够刺激胞囊的孵化,而抗病品种根系分泌物对胞囊的孵化未表现明显刺激作用。同时,在研究不同抗性品种根系分泌物对SCN二龄幼虫趋化性的影响时还发现,感病品种根系分泌物对SCN二龄幼虫表现了明显的吸引性。在供试的5种大豆品种根系分泌物中共检测到了14种氨基酸,只有精氨酸和脯氨酸在抗感品种中均未检测到。根系分泌物中,氨基酸的总含量在感病品种中的平均表达量为87.90mg.L-1,显著高于在抗病品种中的平均表达量(26.77 mg.L-1),其中谷氨酸、甘氨酸、丙氨酸、亮氨酸、赖氨酸和苯丙氨酸等的表达量与抗病性呈一定负相关,而酪氨酸和半胱氨酸的表达量与抗病性呈一定正相关。

Root exudates were collected from five soybean cultivars with different resistance to SCN. Free amino acids from the exudates were detected using an automatic amino acid analyzer and their relationships with the resistance of soybean cyst nematode were studied. The results indicated that the types and contents of amino acids examined were different in these root exudates. Root exudates of susceptible cuhivars stimulated hatching cyst of SCN, and attracted to the J2 of SCN. Fourteen kinds of amino acids were detected in root exudates, but arginine and Proline were not found.The general amino acid content decreased along with the decrease of resistance capability in these soybean varieties. A significant negative relationship was found between the disease resistance and the contents of glutamic acid, glycine, alanine, teucine, lysine and phenylalanine. The resistance to SCN was highly correlated with the contents of tyrosine and cysteine.