Zhou Hang, Liang Xiaoyan, Feng Naijie, Zheng Dianfeng, Qi Deqiang
College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang 524000, China; Shenzhen Reseach Institute of Guangdong Ocean University, Shenzhen 518108, China.
College of Agronomy, Heilongjiang Bayi Agricultural University, Daqing 163000, China.
Ecotoxicol Environ Saf. 2021 Aug 14;224:112619. doi: 10.1016/j.ecoenv.2021.112619.
Studying the mechanism of drought stress in soybean root at vegetative cotyledon (VC) stage by soaking seeds with uniconazole revealed new insights into soybean stress physiology. Therefore, a completely random pot experiments with different time gradients for water cut-off (24, 48, 72, 96 and 120 h, respectively) were carried out with uniconazole (0.4 mgL) with respect to morphological, microscopic, ultramicroscopic, physiological, and molecular studies on varieties Hefeng55 (H50, drought tolerant variety) and Kenfeng16 (K16, drought susceptible variety). Results revealed that uniconazole effectively alleviated the inhibition on root growth caused by drought stress, increased the number of root tips, significantly reduced lignification of vessels, alleviated the damage of mitochondria and nucleus caused by drought stress, further strengthened osmotic adjustment system and antioxidant system, especially when the soil moisture content was less than 14%, broke expression restriction of IAA due to drought stress, and inhibited GA generation; finally, we found that high-intensity drought stress significantly increased the expression levels of GmNAC003, GmNAC004, GmNAC015, GmNAC020, GmHK07, GmRR01, GmRR02 and GmRR16 genes relating to drought tolerance, while uniconazole had a significant inhibitory effect on GmNAC003, GmNAC004, GmNAC015, GmNAC020, GmRR01, GmRR02 and GmRR16 genes. Our results provided a reference for the mechanism of drought resistance in legume and the effect of uniconazole on alleviating drought stress.
通过用烯效唑浸种研究大豆子叶期（VC）根系干旱胁迫机制，为大豆胁迫生理学提供了新见解。因此，以合丰55（H55，耐旱品种）和垦丰16（K16，干旱敏感品种）为材料，进行了完全随机盆栽试验，设置不同断水时间梯度（分别为24、48、72、96和120小时），并施加烯效唑（0.4mg/L），开展形态学、显微镜、超显微镜、生理学及分子研究。结果表明，烯效唑有效缓解了干旱胁迫对根系生长的抑制，增加了根尖数量，显著降低了导管木质化，减轻了干旱胁迫对线粒体和细胞核的损伤，进一步增强了渗透调节系统和抗氧化系统，尤其在土壤含水量低于14%时，打破了干旱胁迫对生长素（IAA）表达的限制，并抑制了赤霉素（GA）的生成；最后，我们发现高强度干旱胁迫显著提高了与耐旱性相关的GmNAC003、GmNAC004、GmNAC015、GmNAC020、GmHK07、GmRR01、GmRR02和GmRR16基因的表达水平，而烯效唑对GmNAC003、GmNAC004、GmNAC015、GmNAC020、GmRR01、GmRR02和GmRR16基因有显著抑制作用。我们的研究结果为豆类作物抗旱机制及烯效唑缓解干旱胁迫的作用提供了参考。
