Abstract：
Gummy stem blight (GSB), a widespread disease causing great loss to cucurbit production, has become a major threat to melon cultivation. However, the melon-GSB interaction remains largely unknown. Here, full-length transcriptome and widely targeted metabolome were used to investigate the defence responses of resistant (PI511089) and susceptible (Payzawat) melon accessions to GSB pathogen infection at 24 h. The biosynthesis of secondary metabolites and MAPK signalling pathway were specifically enriched for differentially expressed genes in PI511890, while carbohydrate metabolism and amino acid metabolism were specifically enriched in Payzawat. More than 1000 novel genes were identified and MAPK signalling pathway was specifically enriched for them in PI511890. There were 11 793 alternative splicing events involving in the defence response to GSB. Totally, 910 metabolites were identified in Payzawat and PI511890, and flavonoids were the dominant metabolites. Integrated full-length transcriptome and metabolome analysis showed eriodictyol and oxalic acid were the potential marker metabolites for GSB resistance in melon. Moreover, posttranscription regulation was widely involved in the defence response of melon to GSB pathogen infection. These results not only improve our understanding on the interaction between melon and GSB, but also facilitate the genetic improvement of melon with GSB resistance.
摘要：
软糖枯萎病（GSB），一种广泛的疾病，对葫芦的生产造成巨大损失，已经成为甜瓜种植的主要威胁。然而,甜瓜-GSB的相互作用在很大程度上仍然未知。这里,使用全长转录组和广泛靶向的代谢组来研究抗性（PI511089）和易感（Payzawat）甜瓜在24小时对GSB病原体感染的防御反应。次级代谢产物的生物合成和MAPK信号通路在PI511890中特异性富集差异表达基因，而碳水化合物代谢和氨基酸代谢在Payzawat中特异性富集。在PI51890中鉴定了超过1000个新基因，并为它们特异性富集了MAPK信号通路。对GSB的防御反应涉及11793个可变剪接事件。完全正确,在Payzawat和PI511890中鉴定出910种代谢物，黄酮类化合物是主要代谢物。整合的全长转录组和代谢组分析显示，苦参碱和草酸是甜瓜GSB抗性的潜在标记代谢产物。此外，转录后调控广泛参与甜瓜对GSB病原体感染的防御反应。这些结果不仅提高了我们对甜瓜和GSB之间相互作用的理解，而且还有利于具有GSB抗性的甜瓜的遗传改良。
