接种AM真菌对烤烟生长、营养及抗旱性的影响

Effects of Arbuscular Mycorrhizal Fungi on Growth,Nutrition and Drought Resistance of Flue-cured Tobacco Seedlings

试验利用漂浮育苗技术,接种丛枝菌根真菌根内球囊霉(Glomus intraradices 193,编号BEG-193)、幼套球囊霉(Glomuse etunicatum,编号BEG-168和BGC-HEB07A)生产菌根烟苗,研究了AM真菌对烤烟生长、营养和抗旱性的影响。结果表明,烟苗生长对水分供应比较敏感,轻度干旱使它们的生物量降低27.24%。在干旱条件下,接种BEG-193和BGC-HEB07A的烟苗生物量显著高于不接种,接种BEG-168无效。接种AM真菌总体上有益于提高烟苗的氮、磷、钾含量和吸收量。此外,干旱使叶片丙二醛含量显著增加了1.71倍(轻度干旱)和5.56倍(重度干旱);而只有在重度干旱条件下叶绿素含量和根系活力才会显著降低,说明干旱容易造成膜脂氧化伤害。接种AM真菌之后,干旱时叶片丙二醛含量低于但叶绿素含量和根系活力高于不接种的烟苗,说明接种AM减轻了干旱对细胞膜的伤害作用,并保持了较强的光合作用和养分吸收能力。接种AM真菌对烟苗生物量、营养状况、丙二醛、叶绿素和根系活力的影响因菌株不同而异,也与干旱程度有关。在生产菌根苗的过程中,选择适宜的菌株是必要的。

Flue-cured tobacco seedlings were grown in the culture boxes floating on nutrient solution and inoculated without and with Glomus intraradices 193（BEG-193）and Glomuse etunicatum 168 and HEB07A（BEG-168 and BGC-HEB07A）,respectively.Thereafter,the seedlings were used to investigate the growth,nutrition and drought resistance.The results indicated the sensitivity of the seedlings to water stress and the decrease in biomass by 27.24% in light drought compared with normal water supply.The seedling biomasses inoculated with BEG-193 and BGC-HEB07A were higher than that without inoculation,while there was no difference between BEG-168 inoculation and non-inoculation.Fungal inoculation increased generally in the concentration and absorption of nitrogen,phosphorus and potassium.In addition,malondialdehyde increased by 1.71（light drought）and 5.56 folds（serious drought）,respectively.However,chlorophyll and root activity were reduced only in serious drought condition.The results suggested easy damage of membrane lipoids under water stress.It was observed the lower malondialdehyde but the higher chlorophyll and root activity following fungal inoculation compared with non inocculation.Therefore,fungal inoculation might reduce the damages of membrane lipoids and keep photosynthesis and root activity.It is necessary to point out the influence of fungal inoculation on growth,nutrition,malondialdehyde,chlorophyll and root activity varied in fungal strains and drought degrees.Suitable fungal stains should be selected in tobacco seedling cultivation.