Yang Xian'an, Wang Shiwei, Jiang Zhenbin, Zhang Cuifang, Zhao Long, Cui Yutong
College of Forestry and Landscape Architecture, Xinjiang Agricultural University, Urumqi 830052, China.
Key Laboratory of Forestry Ecology and Industry Technology in Arid Region, Xinjiang Agricultural University, Urumqi 830052, China.
Plants (Basel). 2024 Dec 15;13(24):3504. doi: 10.3390/plants13243504.
Whether the calyx tube of the Korla fragrant pear falls off seriously affects the fruit quality. 'Xinnonglinxiang' is a mutant variety of the Korla fragrant pear, which has a high calyx removal rate under natural conditions, and calyx tube fall seriously affects the fruit quality. The mechanism behind the high calyx removal rate of 'Xinnonglinxiang' remains unclear; thus, Korla fragrant pear (PT) and 'Xinnonglinxiang' (YB) with different degrees of calyx abscission were used as examples and the abscission areas of calyx tubes were collected in the early (21 April), middle (23 April), and late (25 April) shedding stages to explore the regulatory mechanism behind the abscission. The combination of the results of physiological, cytological, and transcriptomic methods indicated the highest number of differentially expressed genes (DEGs) in the middle of shedding. GO (Gene Ontology) enrichment analysis showed that the expression levels of genes related to the CEL (cellulase) and PG (polygalacturonase) activity functional pathways differed significantly in the two varieties during the three periods, whereas Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were significantly concentrated in the plant hormone signal transduction pathway in all three periods. The expression levels of genes related to the plant hormone signal transduction pathway differed significantly for the two varieties during calyx shedding. Five gene modules were obtained using Weighted Gene Co-Expression Network Analysis (WGCNA), and transcriptome data were correlated with five physiological index values. Two key modules that highly correlated with the Eth (ethylene) response were then screened, and 20 core genes were identified, with , , and likely the hub genes that are involved in the regulation of calyx shedding in the YB variety. The obtained results provide reliable data for the screening of candidate genes for calyx shedding and analysis of the regulatory mechanism behind a high calyx shedding rate, providing a theoretical basis upon which the calyx shedding rate of fruits can be improved through genetic improvement.
库尔勒香梨萼筒脱落与否严重影响果实品质。‘新农林香’是库尔勒香梨的一个突变品种，在自然条件下萼片脱落率高，萼筒脱落严重影响果实品质。‘新农林香’萼片脱落率高的背后机制尚不清楚；因此，以萼片脱落程度不同的库尔勒香梨（PT）和‘新农林香’（YB）为例，在脱落前期（4月21日）、中期（4月23日）和后期（4月25日）采集萼筒脱落区域，以探究脱落背后的调控机制。生理、细胞学和转录组学方法相结合的结果表明，脱落中期差异表达基因（DEG）数量最多。基因本体论（GO）富集分析表明，在三个时期，两个品种中与纤维素酶（CEL）和多聚半乳糖醛酸酶（PG）活性功能途径相关的基因表达水平差异显著，而京都基因与基因组百科全书（KEGG）富集分析表明，在所有三个时期，DEG显著集中在植物激素信号转导途径中。在萼片脱落期间，两个品种中与植物激素信号转导途径相关的基因表达水平差异显著。使用加权基因共表达网络分析（WGCNA）获得了五个基因模块，并将转录组数据与五个生理指标值相关联。然后筛选出与乙烯（Eth）反应高度相关的两个关键模块，并鉴定出20个核心基因，其中 、 和 可能是参与调控YB品种萼片脱落的枢纽基因。所得结果为筛选萼片脱落候选基因和分析高萼片脱落率背后的调控机制提供了可靠数据，为通过遗传改良提高果实萼片脱落率提供了理论依据。
