摘要
【目的】探明不同地被覆盖物对干旱胁迫下银杏生长及抗旱性的影响,为银杏的抗旱栽植及合理防护提供参考。【方法】以3年生无性系扦插苗为试材,通过铺设或种植设置CK(未覆盖)、F_(1)(覆盖腐殖质0.25 kg)、F_(2)(覆盖木片0.25 kg)、F_(3)(覆盖草0.25 kg)4种覆盖处理方式,测定在干旱胁迫下不同地被覆盖处理土壤含水率、银杏苗生长状况、光合参数、丙二醛(MDA)及渗透调节物质含量。【结果】F_(1)的土壤含水率最高(18.84%),分别较CK、F_(2)、F_(3)增加42.97%、28.95%、34.76%,F_(1)与CK、F_(3)间存在显著差异,与F_(2)间差异不显著。F_(2)的银杏总生物量最高(95.38 g),分别较CK、F_(1)、F_(3)增加23.97%、23.50%、36.32%,各处理间差异不显著。F_(1)的根冠比最高(1.01)分别较CK、F_(2)、F_(3)增加5.21%、27.85%和16.09%,各处理间差异不显著。F_(1)的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)最高,分别为2.415μmol/(m^(2)·s)、0.090 mmol/(m^(2)·s)、3.556 mmol/(m^(2)·s),分别较CK增加21.30%、11.11%、17.44%;F_(2)的总生物量、胞间CO_(2)浓度(Ci)最高,分别为95.38 g、410.400μmol/(m^(2)·s),分别较CK增加23.97%、0.70%。MDA含量CK最高(0.011μmol/g),F_(3)、F_(1)、F_(2)分别较CK显著降低54.55%、63.64%、81.82%。可溶性糖(SS)含量CK、F_(3)均显著高于F_(1)、F_(2)。游离脯氨酸(Pro)含量F_(2)最高(47.06μg/g),分别较CK、F_(1)、F_(3)显著增高62.72%、194.86%、245.27%。SS含量与F_(3)的Gs呈显著正相关,与F_(1)的Ci呈显著负相关;Pro含量与F_(2)的生物量呈显著负相关;MDA含量与其他指标相关性不显著。【结论】干旱胁迫下银杏光合生理、MDA及渗透调节物质含量受覆盖物影响较大,可通过地被覆盖腐殖质和木片的方式促进银杏苗的生长及光合作用,一定程度上抑制MDA生成并积累渗透调节物质进行渗透调节,使其抗干旱胁迫能力增强。
【Objective】The effects of different mulches on the growth and drought resistance of Ginkgo biloba under drought stress were studied,which provided reference for planting for drought resistance and reasonable protection of G.biloba.【Method】Using 3-year-old clonal cuttings as experimental materials,four mulching treatments were established through laying or planting:CK(not mulched),F_(1)(mulched with 0.25 kg humus),F_(2)(mulched with 0.25 kg wood chips)and F_(3)(mulched with 0.25 kg grass).Then the measurement was conducted to determine the soil moisture content,growth status,photosynthetic parameters,MDA and osmoregulatory substance levels of G.biloba seedlings under drought stress.【Result】The soil moisture content of F_(1) was the highest(18.84%),which increased by 42.97%,28.95% and 34.76% compared with CK,F_(2) and F_(3),respectively.There were significant differences in F_(1) and CK and F_(3),but no significant differences between F_(1) and F_(2).The total biomass of G.biloba in F_(2) was the highest(95.38 g),and increased by 23.97%,23.50% and 36.32% compared with CK,F_(1) and F_(3),respectively,with no significant difference among treatments.The rootshoot ratio of F_(1) was the highest(1.01),which was 5.21%,27.85% and 16.09% higher than that of CK,F_(2) and F_(3),respectively,with no significant difference among treatments.The net photosynthetic rate(Pn),transpiration rate(Tr)and stomatal conductivity(Gs)of F_(1) were the highest,which were 2.415μmol/(m^(2)·s),0.090 mmol/(m^(2)·s)and 3.556 mmol/(m^(2)·s),respectively,and increased by 21.30%,11.11% and 17.44% compared with CK,respectively.The highest total biomass and intercellular CO_(2)(Ci)was observed in F_(2) with 95.38 g and 410.400μmol/(m^(2)·s),respectively,and increased by 23.97% and 0.70% compared with CK,respectively.The MDA content of CK was the highest(0.011μmol/g),which was 54.55%,63.64% and 81.82% higher than that of F_(3),F_(1) and F_(2),respectively,and was significantly different from F_(1),F_(2) and F_(3).The soluble sugar(SS)content of CK and F_(3) was significantly higher than that of F_(1) and F_(2).The content of Pro in F_(2) was the highest(47.06μg/g),which significantly increased by 62.72%,194.86% and 245.27% compared with CK,F_(1) and F_(3),respectively.SS content was significantly positively correlated with Gs in F_(3) treatment and negatively correlated with Ci in F_(1) treatment.There was a significant negative correlation between Pro content and biomass in F_(2) treatment,while there was no significant correlation between MDA content and other indexes.【Conclusion】Under drought stress,the photosynthetic physiology,MDA and osmoregulatory substances contents of G.biloba were significantly affected by mulch,indicating that it could promote the growth and photosynthesis of G.biloba seedlings by covering humus and wood chips,inhibit the production of MDA to a certain extent,accumulate osmoregulatory substances for osmoregulation,and enhance the the ability to resist drought stress.
作者
张筱
张海芹
高宇琪
夏梦洁
刘军
ZHANG Xiao;ZHANG Haiqin;GAO Yuqi;XIA Mengjie;LIU Jun(Qinling National Botanical Garden,Xi’an,Shaanxi 710404,China)
出处
《贵州农业科学》
2025年第12期135-144,共10页
Guizhou Agricultural Sciences
基金
秦岭国家植物园2023年国家重点野生动植物保护项目
中国科学院植物园体系建设2024年秦岭国家植物园建设。
关键词
银杏
干旱胁迫
光合生理
丙二醛
渗透调节
Ginkgo biloba
drought stress
photosynthetic physiology
malondialdehyde
osmoregulation
