Xu Junxu, Li Qingzhu, Li Ye, Yang Liuyan, Zhang Yongchun, Cai Youming
Forestry and Pomology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.
Agricultural Technology Extension Service Station of Langxia Town, Shanghai, China.
Front Plant Sci. 2021 Jan 20;11:615547. doi: 10.3389/fpls.2020.615547. eCollection 2020.
species have great ornamental and medicinal values; however, their low regeneration efficiency significantly restricts their commercial production. Exogenous hormone application is an effective way to promote bulblet development, but their effect on has not been verified to date. In the present study, we examined the effect of different exogenous hormones on bulblet development in , and found that gibberellic acid (GA) significantly inhibited, whereas paclobutrazol (PBZ), abscisic acid (ABA), and ethrel promoted bulblet development, especially PBZ, a GA biosynthesis inhibitor. Furthermore, GA reduced endogenous cytokinin (CK) content, as well as the activities of carbohydrate metabolism enzymes, including sucrose synthase (SUS) and glucose-1-phosphate adenylyltransferase (AGPase), by downregulating the expression levels of , , and genes encoding AGPase large and small subunits. This resulted in the decrease in carbohydrate accumulation in the bulblets, thus hindering their development. PBZ had the opposite effect to GA on carbohydrate metabolism; it decreased endogenous GA and GA, thereby promoting bulblet development. ABA promoted endogenous auxin content and the activities of starch synthesis enzymes, especially soluble starch synthase (SSS) and granule-bound SS (GBSS), through the up-regulation of the expression levels of , , and genes, which could also result in the accumulation of carbohydrates in the bulblets and promote their development. In addition, ethrel application partly promoted bulblet development by promoting endogenous CK content. Although the accumulation of carbohydrates and the activity of starch enzymes were increased by ethrel treatment, we hypothesized that the effect of ethrel on regulating carbohydrate metabolism may be indirect. Our results could provide a basis for improving the propagation efficiency of for production, as well as propose some directions for future research.
某些物种具有很高的观赏和药用价值；然而，它们较低的再生效率严重限制了其商业化生产。外源激素的应用是促进小鳞茎发育的有效方法，但迄今为止其对[具体内容缺失]的影响尚未得到验证。在本研究中，我们研究了不同外源激素对[具体物种缺失]小鳞茎发育的影响，发现赤霉素（GA）显著抑制小鳞茎发育，而多效唑（PBZ）、脱落酸（ABA）和乙烯利促进小鳞茎发育，尤其是GA生物合成抑制剂PBZ。此外，GA通过下调[相关基因缺失]、[相关基因缺失]以及编码AGPase大亚基和小亚基的基因的表达水平，降低了内源细胞分裂素（CK）含量以及碳水化合物代谢酶的活性，包括蔗糖合酶（SUS）和葡萄糖-1-磷酸腺苷酰转移酶（AGPase）。这导致小鳞茎中碳水化合物积累减少，从而阻碍其发育。PBZ对碳水化合物代谢的影响与GA相反；它降低了内源GA和GA，从而促进小鳞茎发育。ABA通过上调[相关基因缺失]、[相关基因缺失]和[相关基因缺失]基因的表达水平，促进了内源生长素含量和淀粉合成酶的活性，特别是可溶性淀粉合酶（SSS）和颗粒结合型淀粉合酶（GBSS），这也可能导致小鳞茎中碳水化合物的积累并促进其发育。此外，乙烯利处理通过促进内源CK含量部分促进了小鳞茎发育。尽管乙烯利处理增加了碳水化合物的积累和淀粉酶的活性，但我们推测乙烯利对碳水化合物代谢的调节作用可能是间接的。我们的研究结果可为提高[具体物种缺失]的生产繁殖效率提供依据，并为未来的研究提出一些方向。
