弱光及干旱条件下AMF对切花月季光合和AsA-GSH循环的影响

Effects of AMF on Photosynthesis and AsA-GSH Cycle in Cut Rose under Weak Light and Drought Conditions

旨在探究弱光及干旱条件下丛枝菌根真菌(AMF)对切花月季光合、AsA-GSH循环以及渗透调节物质的影响。盆栽条件下设置100%全光照(L1)、50%全光照(L2)2个光照处理组,80%土壤持水量(W1)和40%土壤持水量(W2)2个水分处理组,接种AMF[变形球囊霉(Glomus versiforme)+异形根孢囊霉(Rhizophagus irregularis)]及不接种对照(CK)共8个处理。结果表明,AMF能够侵染切花月季根系,显著提高切花月季生长品质。弱光和/或干旱胁迫下,与不接种对照相比,接种AMF能有效地促进切花月季叶片的净光合速率(P_(n))、蒸腾速率(T_(r))、气孔导度(G_(s))和水分利用效率(WUE)增加,降低细胞间隙CO_(2)浓度(C_(i));在L2W2处理条件下,与不接种对照相比,接种AMF使切花月季叶片中的抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)、单脱氢抗坏血酸还原酶(MDAR)和脱氢抗坏血酸还原酶(DHAR)活性分别提高5.2%、15.4%、21.7%和35.9%;接种AMF的抗坏血酸(AsA)含量与对照处理无显著差异,还原型谷胱甘肽(GSH)含量提高8.1%,GSH/GSSG比值增加7.9%;接种AMF后切花月季丙二醛(MDA)含量显著降低,可溶性糖、可溶性蛋白和脯氨酸(Pro)含量明显增加。结论认为AMF通过维持AsA/DHA和GSH/GSSG的稳定,提高AsA-GSH循环中相关酶活性,增加切花月季叶片可溶性糖、可溶性蛋白和脯氨酸含量而降低MDA含量来适应水分和光照的变化,形成适应光照和水分条件变化的生理生态对策来改善切花月季生长品质。

To explore the effects of Arbuscular mycorrhiza fungi(AMF)on photosynthesis,AsA-GSH cycle and osmoregulation substances in cut roses under low light and drought conditions,two light treatment groups were set under potted conditions:100%full light(L1)and 50%full light(L2).The relative soil moisture content was maintained at 80%of soil moisture capacity(W1)and 40%of soil moisture capacity(W2).A total of 8 treatments,including inoculation with AMF[Glomus versiform+Rhizophagus irregularis]and a control group(CK).The results showed that AMF could infect the root system of cut rose and significantly promote their growth and quality.Under low light and/or drought stress,compared with the control group,inoculation with AMF effectively promoted the increase in net photosynthetic rate(P_(n)),transpiration rate(T_(r)),stomatal conductance(G_(s)),and water use efficiency(WUE)of cut rose leaves,while reducing the intercellular CO_(2)concentration(C_(i));under L2W2 treatment conditions,compared with the control group,inoculation with AMF increased the activities of ascorbic acid peroxidase(APX),glutathione reductase(GR),monodehydroascorbic acid reductase(MDAR),and dehydroascorbic acid reductase(DHAR)in cut rose leaves by 5.2%,15.4%,21.7%,and 35.9%,respectively;there was no significant difference in ascorbic acid(AsA)content among AMF vaccinated individuals.The reduced glutathione(GSH)content increased by 8.1%,and the GSH/GSSG ratio increased by 7.9%;after inoculation with AMF,the content of malondialdehyde(MDA)in cut roses significantly decreased,while the content of soluble sugar,soluble protein,and proline(Pro)significantly increased.In conclusion,AMF adapts to changes in water and light by maintaining the stability of AsA/DHA and GSH/GSSG,increasing the activity of related enzymes,increasing the content of soluble sugar,soluble protein,and proline in cut rose leaves,while reducing MDA content.This adaptation allows it effectively utilizes weak light radiation,improves photosynthesis,and forms physiological and ecological strategies that adapt to changes in light and water conditions to improve the growth quality of cut rose.