摘要
内生真菌是生活在健康植物的茎叶内 ,形成不明显感染的一类真菌。以黑麦草 (LoliumperenneL .)为实验材料 ,研究在不同强度的干旱胁迫下内生真菌 (Neotyphodiumlolii)侵染对其叶片延伸生长、分蘖数和生物量的影响。结果表明 ,与非感染种群相比 ,内生真菌感染对黑麦草叶片延伸速率无明显促进作用 ;内生真菌感染种群具有明显较多的分蘖数 ;在重度胁迫并经过恢复期后 ,内生真菌感染种群具有较高的根冠比。
Endophytes are fungi that form inapparent infection within leaves and stems of healthy plants. Endophytes or endophytic fungi exist widely in the higher plants and are generally considered as mutual symbiotes to the host plants. The present study examined the association of an endophyte (Neotyphodium lolii) with its host plant, Lolium perenne cv. Pinnacle. Both endophyte status and drought stress level were considered. Endophyte-free (EF) plants were obtained by a mild heat treatment while endophyte-infected (EI) plants were germinated directly. After transplantation and four weeks of growth in pots, EF and EI plants were subjected to drought stress of different water status in the soil; soil moisture was maintained at 20% to 40%, 40% to 60%, 60% to 80%, and over 80% of the field capacity. Leaf extension rate and tiller numbers were measured during drought stress, and biomass was determined after recovery stage. Our objective was to determine the influence of endophyte infection on growth characteristics and drought resistance of the host plants. Leaf extension of Lolium perenne shifted during drought stress, while no significant superiority was found in EI plants as compared with EF plants. The EI plants tended to produce more tillers than the EF plants during drought stress. After severe stress and recovery stage, the EI populations had a significantly higher root/shoot ratio than the EF populations, while there was no significant difference in total biomass between EI and EF populations. Our results indicated that endophyte infection might enhance the drought resistance of the host plant by enhancing its tiller production during drought stress and its photosynthate allocation to roots between stress periods.
出处
《植物生态学报》
CAS
CSCD
北大核心
2002年第5期621-626,共6页
Chinese Journal of Plant Ecology
基金
国家重点基础研究发展规划项目 (G2 0 0 0 0 186 0 1)
国家自然科学基金项目 ( 39870 14 2 )
关键词
内生真菌感染
干旱胁迫
黑麦草
生长
Endophyte, Lolium perenne L., Drought stress, Leaf extension rate, Tiller number, Biomass
