Evaluation of flower scent and its control by molecular breeding

1.为了揭示绞股蓝恶臭的传递途径，对其相关酶活性及前体的使用效果进行了研究。喷施L亮氨酸，3-甲基丁酸排放量增加3倍。丙酮酸脱羧酶(PDC)活性在开花前较高，开花后急剧下降。开花时催化合成3-甲基丁酸的丙酮酸脱氢酶(PDH)活性最高。在开放小花中，催化异戊酰辅酶A合成3-甲基丁酸的酰基辅酶A水合酶(ACH)活性也很高。意识到了关于花的气味的红色。有可能在四代后选择出强气味或弱气味品系。3.有可能检测到花香的AFLP标记。4.我们尝试克隆了PDC基因。用两对简并引物和两个RT-PCR引物，即5‘-Race法和3’-Race法，分离到约86%的基因。用此信息后的引物，用RT-PCR检测PDC基因的表达。该基因的表达水平随小花发育阶段的不同而变化。然而，PDC基因的表达与酶活性之间没有很强的相关性。5.使用异戊醇、苯甲醇和2-苯乙醇切花时，3-甲基丁酸的释放量降低到57%~39%。

1.In order to reveal the pass way of unpleasant odor emitted by Gypsophyla paniculata, enzymatic activity concerned and effect of precursor application was investigated. 3-methylbutylic acid emission increased three times by L-leucine application. Activity of pyruvate decarboxylase (PDC) was high in before opening florets, then decreased dramatically after opening. Pyruvate dehydrogenase (PDH) activity, which catalyzes 3-methylbutylic acid synthesis, was highest in opening florets. Acyl-CoA hydrase (ACH) activity, which catalyze 3-methylbutylic acid synthesis from isovaleroyl Co-A was also high in opening florets.2.Selection of Gypsophyla elegans var. carminea concerning the flower odor was realized. It was possible to select strong or weak odor lines after four generations.3.It was possible to detect AFLP marker for the flower odor.4.We tried to clone PDC gene. Using two pairs of degenerate primers, two RT-PCR primers, 5'-Race method and 3'-Race method, about 86% of the gene was isolated. Using the primers after this information, PDC gene expression was measured by RT-PCR. The expression level of this gene was changed with floret developmental stages. However, strong relationship between PDC gene expression and enzymatic activity could not be found.5.When isoamylalcohol, benzylalcohol and 2-phenylethylalcohol were applied to cut flower of G.paniculata, emission of 3-methylbutylic acid was decreased to 57 to 39%.