根际微生物响应再生稻衰老的演变特征及其延效机制
Evolution characteristics of rhizosphere microorganisms in response to ratoon rice senescence and underlying carry-over effect mechanism
郭春林 1林满红 1陈婷 2陈鸿飞 2林文芳 3林文雄4
作者信息
- 1. 福建省农业生态过程与安全监控重点实验室/作物生态与分子生理学福建省高校重点实验室,福建福州 350002
- 2. 福建省农业生态过程与安全监控重点实验室/作物生态与分子生理学福建省高校重点实验室,福建福州 350002;福建农林大学菌草与生态学院,福建福州 350002
- 3. 福建农林大学生命科学学院,福建福州 350002
- 4. 福建省农业生态过程与安全监控重点实验室/作物生态与分子生理学福建省高校重点实验室,福建福州 350002;福建农林大学菌草与生态学院,福建福州 350002;福建农林大学生命科学学院,福建福州 350002
- 折叠
摘要
探索根际微生物响应再生稻生育后期植株衰老进程的菌群演变规律及其生态对策是防止作物早衰发生,促进耕地土壤肥力和作物生产力协同提升的关键.本研究选用 2 个具有亲缘关系的常规再生稻品种黄华占(Huanghuazhan,HHZ)和丰华占(Fenghuazhan,FHZ)为供试材料,采用高通量测序等方法研究再生稻生育后期根际菌群随植株衰老进程而发生的多样变化、菌群演变生态策略和物种间生态位关系.结果表明,2 个具有紧密亲缘关系的供试品种其生育后期的自然衰老变化趋于一致.但在同等施肥条件下,丰华占生育后期的所有相关生理指标衰败速度均明显高于黄华占,即呈现早衰现象,并显著影响其头季和再生季稻的干物质积累与籽粒灌浆结实,进而减产.进一步分析结果证实,根际微生物多样性与再生稻植株的衰老进程紧密关联,具体表现在随着再生稻生育后期的推进,FHZ 根际微生物多样性 Chao 1 指数和 Shannon 指数下降幅度更大,根际微生物生态位宽度变小.进一步分析发现,HHZ头季稻成熟期较FHZ头季稻成熟期根际土壤显著提高了地杆菌属(Geobacter)、卤囊菌属(Haliangium)、亚硝酸盐氧化菌属(Candidatus_Nitrotoga)以及硝化螺菌属(Nitrospira)的相对丰度(0.61%、0.17%、0.42%和 0.045%);而在慢生根瘤菌属(Bradyrhizobium)、鞘脂单胞菌属(Sphingomonas)以及芽单胞菌属(Gemmatimonas)上HHZ较FHZ显著下降了 0.29%、0.76%和 0.15%;HHZ根际上调的微生物在土壤的营养循环和有效性转化上起到重要功能作用,其根际土壤微生物生态位宽度比FHZ高36.81%,反映了根际微生物对资源利用的差异,是微生物适应土壤胁迫环境的生物印迹.本研究认为植物早衰发生是根际微生物生态对策的结果,再生稻头季植株根际土壤微生物群落结构差异对其再生季具有显著的延效作用.因此,加强再生稻头季后期的根际调控,强化根际土壤微生物菌群的合理构建,促进根际正效应形成,是活化土壤营养环境,防止再生稻早衰发生,进一步提升再生季稻产量的关键.
Abstract
The objective of this study is to investigate the ecological strategies and evolutionary patterns of rhizosphere microor-ganisms at the late stages of ratoon rice growth,which is crucial for preventing premature crop senescence,enhancing crop productivity,and improving soil fertility in cultivated land.In this study,two genetically related conventional ratoon rice varieties,namely Huanghuazhan(HHZ)and Fenghuazhan(FHZ),were selected as the experimental materials.We employed high through-put sequencing and correlation analysis to explore the changes in diversity,ecological strategies,and inter-species niche relation-ships of rhizosphere microbiota at the late growth stage of ratoon rice with respect to plant aging.The results demonstrated a con-sistent trend in the natural aging changes at the late growth stages of both varieties.However,under identical fertilization condi-tions,FHZ exhibited a significantly higher decay rate of all relevant physiological indicators compared to HHZ at the late growth stage.This observation suggested that the premature aging greatly impacted dry matter accumulation,grain filling,and seed-setting in both seasons,ultimately leading to reduced crop yield.Further analysis confirmed a close relationship between rhizosphere microorganism diversity and the aging process of ratoon rice.Specifically,FHZ showed a significant decrease in rhizosphere microbial diversity index and niche width during the development of ratoon rice's late growth period.Conversely,Agrobacterium(0.61%),Halocystium(0.17%),Nitrite Oxidizing Bacteria(0.42%),and Nitrospiridium genera(0.045%)were more prominent in HHZ during main crop maturity period(HMR)compared to FHZ's main crop maturity period(FMR).On the other hand,Bradyrhizobium(0.29%),Sphingomonas(0.76%),and Gemmatimonas(0.15%)displayed an opposite pattern for these genera.Furthermore,we observed that up-regulated microorganisms in HHZ's rhizosphere played a crucial role in nutrient cycling and availability as well as soil transformation processes.Additionally,the niche breadth of rhizosphere soil microorganisms was 36.81%higher in HHZ compared to FHZ,indicating their adaptive response to soil stress environments.This phenomenon re-flected the variations in resource utilization by rhizosphere microorganisms,thereby elucidating the evolutionary dynamics and competitive ability for resources among them,ultimately impacting the growth,development,and yield of ratoon rice plants.This study suggests that plant premature senescence is a consequence of an ecological strategy employed by rhizosphere microorgan-isms.Furthermore,differences in the structure of rhizosphere soil microbial communities during the initial season significantly delay their regeneration season in ratoon rice cultivation.In conclusion,enhancing regulation within the rhizosphere environment,establishing a rational construction of rhizosphere soil microbial communities,and promoting positive effects on plant growth are crucial processes for activating soil nutrients,preventing premature senescence in ratoon rice plants,and further improving its yield.
关键词
再生稻/早衰/根际微生物/根际效应/栽培调控Key words
ratoon rice/premature senescence/rhizosphere microorganisms/rhizosphere effects/cultivation regulation引用本文复制引用
基金项目
国家重点研发计划项目(2016YFD0300508)
国家重点研发计划项目(2017YFD0301602)
福建省科技厅对外合作项目(2018I0002)
出版年
2024
国家科技期刊平台
NSTL
万方数据