制干辣椒果实辣椒素对干旱、盐及其双重胁迫的响应

Capsaicin of dry pepper fruit grown under drought, salt and combined stress condition

为明确干旱、盐等环境因素对制干椒辣椒素含量的影响,试验以红龙23号板椒为材料,从现蕾期开始设置不同土壤含水量65%(W1)、45%(W2)和NaCl(S1=120 mmol·L^(-1))及盐旱复合处理(W1S1、W2S1),利用高效液相色谱法分析转色期果实辣椒素素含量,并送样进行转录组测序。结果表明,W1处理下辣椒素含量较对照增加107.11%,W2处理时辣椒素含量下降73.01%;含盐处理均能提高辣椒素含量,其中W2S1处理的较对照高392%。盐、旱胁迫主要影响苯丙烷生物合成途径,其中HCT、4CL、CAD等基因表达受影响较大;聚类分析表明BCKDHE2、ENRb等基因主要响应干旱胁迫,CCR、GS2主要响应盐胁迫。由上可知,适度干旱和盐胁迫均能提高辣椒素含量;干旱加剧时与盐分的复合效应更显著,对辣椒素积累的促进作用更大。

Honglong 23 pepper was cultivated in pots stressed with drought and salt from budding to fruit color break to understand the effects of stress on capsaicin in pepper fruit for drying.Soil water contents were 65%(W1)and 45%(W2)of saturated content,NaCl concentration was 120 mmol·L^(-1)(S1),and combined stresses were W1S1 and W2S1.Capsaicin contents were measured with HLPC,transcriptional data was analyzed by Personal Biotechnology Co Ltd.The results showed that the capsaicin content of pepper fruit under W1 treatment was 107.11%higher than that of the control,and the capsaicin content with W2 treatment was 73.01%lower than that of the control.Salt treatments(S1,W1S1,W2S1)increased the capsaicin content,and the capsaicin content in W2S1 treatment was 3.92 times of the control.Salt and drought stresses mainly affected the phenylpropane biosynthesis pathway of capsaicin,and had a great impact on the expression of HCT,4CL,CAD genes in phenylpropane pathway.Cluster analysis showed that CPR,pAMT2 genes responded to the three stresses,while BCKDH E2,ENRb mainly responded to water stress,CCR and GS2 mainly responded to salt stress.Moderate drought and salt stress can increase the content of capsaicin in fruits.The combination of severe drought and salt had the most significant effect on capsaicin,while the mild drought and salt had little effect.