Page 6 - 《广西植物》2024年第10期
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1 8 0 8 广 西 植 物 44 卷
WANG Xinyeꎬ ZHANG Minꎬ TIAN Xiaolongꎬ YUAN Pingꎬ LI Hongxiaꎬ
∗
LUO Zhenbiaoꎬ YUE Qianqianꎬ ZHAO Liang
( Moutai Instituteꎬ Renhuai 564500ꎬ Guizhouꎬ China )
Abstract: Glutinous sorghum is an important raw material for the production of Baijiu (Chinese liquor). During its
growth processꎬ glutinous sorghum requires a substantial amount of chemical fertilizers. As an environmentally friendly
fertilizerꎬ microbial agent has a great application prospect in future. The aim of this paper was to develop a growth
promoting microbial agent for glutinous sorghum. In this studyꎬ the glutinous sorghum leaves were used as experimental
materials to isolate and screen microbial strains with plant growth hormone indole acetic acid ( IAA) production
ability. Phylogenetic analysis was performed to determine the taxonomic status of these microbial strains based on the 16S
rDNA conserved sequences. The effects of strains on glutinous sorghum seed germination were analyzed by soaking the
seeds with bacterial suspension. The effects of strains on the sorghum seedlings growth were analyzed by pot
experiment. The results were as follows: (1) Four microbial strains capable of producing IAA were isolated and screened
from glutinous sorghum leavesꎬ designated as HY1 ̄1ꎬ HY1 ̄2ꎬ HY1 ̄3ꎬ and HY1 ̄4. Among themꎬ HY1 ̄1 exhibited the
 ̄1
highest IAA production per unit concentration which was 2.56 molL . (2) Bayesian inference tree analysis based on
the 16S rDNA sequences revealed that all four strains belonged to Bacillus subtilis. (3) HY1 ̄1ꎬ HY1 ̄2ꎬ HY1 ̄3ꎬ and
HY1 ̄4 could promote the glutinous sorghum seed germination rates. Compared to the control groupsꎬ the germination
rates of glutinous sorghum seeds soaked in bacterial suspension significantly increased by 40.04% to 165.52%. Among
themꎬ HY1 ̄1 demonstrated the most prominent promotion effectꎬ with a germination rate increase of 165.52%. (4)
HY1 ̄1 strain was selected for a pot experiment. After 30 days of inoculation on the roots of glutinous sorghum seedlingsꎬ
the plant heights of the seedlings significantly increased by 29.17%ꎬ and total phosphorus content increased significantly
by 5.12%. The rhizosphere substrate of glutinous sorghum exhibited a significant increase in available nitrogen content by
31.70% and available phosphorus content by 28.88%. In conclusionꎬ HY1 ̄1ꎬ an endophytic bacterium in glutinous
sorghum leavesꎬ can promote the growth of glutinous sorghum plants by secreting the plant growth hormone IAA and
providing necessary nutrients. This study provides genetic resources for the further development of microbial agent
targeting the growth promotion of glutinous sorghum.
Key words: plant endophytic bacteriaꎬ isolation and screeningꎬ plant growth hormone IAAꎬ seed germinationꎬ glutinous
sorghum growth promoting
糯高粱胚乳中支链淀粉含量较高ꎬ蒸煮后黏 生菌主要是通过垂直传播和水平传播的方式获得
性强ꎬ是酿 造 优 质 白 酒 的 重 要 原 料 ( 丁 延 庆 等ꎬ (Balint et al.ꎬ 2013)ꎬ叶片的内部组织是一个吸引
2019)ꎮ 高粱产量的提高离不开肥料的使用ꎬ氮肥 大量细菌和真菌的环境ꎬ含有丰富的微生物资源
是高粱增产的主要因素ꎬ磷肥次之ꎮ 然而ꎬ持续的 (Vandenkoornhuyse et al.ꎬ 2015)ꎮ 宿主植物为内
高化肥投入会造成肥料利用效率降低、土壤环境 生菌提供持续的营养供应ꎬ作为回报ꎬ内生菌通过
破坏、水体污染等问题( 陈同斌等ꎬ 2002ꎻ董二伟 磷酸 盐 溶 解、 氮 固 定、 植 物 生 长 激 素 吲 哚 乙 酸
等ꎬ 2012)ꎮ 微生物有机肥既能增加植物养分的 (IAA)产生、铁载体产生、ACC(1 -氨基环丙烷 ̄1 ̄
供应量、促进植物生长、提高产量、改善农产品品 羧酸)水解酶合成等促进植物对营养元素的吸收ꎬ
质及农业生态环境ꎬ也能减轻植物病虫害、减少化 直接或间接促进植物生长( Cueva ̄Yesquén et al.ꎬ
肥使用量ꎮ 因此ꎬ微生物有机肥在可持续农业战 2021)ꎮ 植物内生细菌与寄主植株在长期共同进
略发展中的地位日趋重要( 李西强等ꎬ 2013)ꎮ 植 化过程中形成了密切的相互关系ꎬ成为化肥和其
物内生菌存在于植物的根、茎、叶、树皮、花和种子 他微生物制剂的最佳竞争者ꎬ其合理应用将减少
里ꎬ对 植 物 的 健 康 和 发 育 有 良 好 的 促 进 作 用 化学农药和肥料对环境的污染ꎬ有利于保持生态
(Dudeja et al.ꎬ 2011ꎻSantoyo et al.ꎬ 2016)ꎮ 叶内 平衡(梁志超等ꎬ 2019)ꎮ