中国水稻科学2024，Vol.38Issue(4)：437-446,10.DOI:10.16819/j.1001-7216.2024.230805
根际饱和溶解氧对水稻分蘖期光合及生长特性的影响
Effects of Rhizosphere Saturated Dissolved Oxygen on Photosynthetic and Growth Characteristics of Rice at Tillering Stage
摘要
Abstract
[Objective]Studying the regulatory effects of rhizosphere saturated dissolved oxygen(RSDO)during the tillering stage on rice photosynthesis and chlorophyll fluorescence parameters is of great significance for improving rice light energy utilization efficiency and optimizing rice oxygen nutrition cultivation theory.[Method]This study conducted a hydroponic experiment using three ecological types of rice varieties,namely lowland rice,deep-water rice,and upland rice,as experimental materials.Two treatments,rhizosphere saturated dissolved oxygen(RSDO)and natural growth(CK),were set up to measure chlorophyll fluorescence parameters,photosynthetic characteristics,and dry matter accumulation during the rice tillering stage.[Result]Under the conditions of rhizosphere saturated dissolved oxygen,the leaf light response curves of lowland rice and deep-water rice decreased.When the light intensity exceeded 500μmol/(m2 s),the difference in curves with the control group increased.The fitting of the light response curve indicates that rhizosphere saturated dissolved oxygen reduces the maximum net photosynthetic rate(Pnmax),apparent quantum efficiency(Q),dark respiration rate(Rd),and light compensation point(LCP)of rice leaves.The maximal photochemical efficiency(Fv'/Fm'),the actual photochemical efficiency(ΦPSⅡ),electron transfer rate(ETR),and photochemical quenching coefficient(qp)of the three rice varieties under RSDO were lower than those of CK,while the non-photochemical quenching(NPQ)and 1-qp were increased.Rhizosphere saturated dissolved oxygen can increase the nighttime respiration rate(Rn)and intercellular CO2 concentration(Ci)of rice.The leaf chlorophyll a,chlorophyll b,and total chlorophyll contents of three rice varieties all showed RSDO＜CK,while carotenoid content and relative conductivity showed RSDO＞CK.The saturated dissolved oxygen in the rhizosphere significantly reduced the aboveground dry matter mass and leaf area index of lowland rice and deep rice,with a decrease of 12.6％,9.4％,and 9.2％,6.6％,respectively,compared to the control.There was no significant difference between the treatments of upland rice varieties.[Conclusion]RSDO inhibits the synthesis of photosynthetic pigments in rice leaves,reduces leaf PSⅡperformance and light energy utilization efficiency,which is not conducive to early rice growth.Compared to lowland rice and deep-water rice,upland rice has better adaptability to RSDO.关键词
水稻/根际氧/荧光参数/光响应曲线/光系统Ⅱ/叶绿素/分蘖期Key words
rice/rhizosphere oxygen/fluorescence parameters/light-response curve/PS Ⅱ/chlorophyll/tillering stage引用本文复制引用
胡继杰,胡志华,张均华,曹小闯,金千瑜,章志远,朱练峰..根际饱和溶解氧对水稻分蘖期光合及生长特性的影响[J].中国水稻科学,2024,38(4):437-446,10.基金项目
国家重点研发计划资助项目(2022YFD2301404) （2022YFD2301404）
国家自然科学基金资助项目(31771733) （31771733）
浙江省水稻新品种选育重大科技专项(2021C02063-3). （2021C02063-3）
