烯效唑对番茄苗上胚轴的矮化作用及机制分析OA

The high temperature and small temperature difference between day and night in horticultural facilities are easy to occur in summer,which causes tomato(Solanum lycopersicum)seedlings to overgrow,especially the epicotyl,resulting in lower yields and economic losses.As an inhibitor of gibberellin synthesis,uniconazole can delay cell elongation and inhibit the seedling to overgrow.In order to clarify the effect of uniconazole on epicotyl dwarfing in tomato,0,15,45 and 75 mg/L uniconazole solutions were sprayed on long internode'DH'tomato seedlings,and the morphological indexes of tomato seedlings were measured at 7 d intervals after spraying,such as epicotyl length,epicotyl thickness,plant height,leaf width and leaf length,and measured the quality indicators of tomato fruits after planting.The results showed that 45 mg/L of uniconazole significantly reduced epicotyl length and plant height in tomato seedlings,and significantly increased soluble protein and soluble solids contents in tomato fruits.The expression of genes in the gibberellic acid(GA)and indole-3-acetic acid(IAA)regulatory pathway in the tomato epicotyl at 7 d after uniconazole treatment were analyzed.The results showed that the majority of genes in the GA regulatory pathway genes showed up-regulated expression patterns.Auxin response factor 13(SlARF13)gene in the IAA regulatory pathway also showed up-regulated expression patterns,whereas SlIAA33 gene showed down-regulated expression patterns.Therefore,GA2ox3 and GA2-β-dioxygenase8 gene in the GA pathway and the SlARF13 and SlIAA33 genes could be used as candidate genes for tomato epicotyl dwarfing.This study provides a theoretical basis for the subsequent application of uniconazole in tomato seedling.