冰草生长繁殖对温度、水分和刈割的响应  

Response of Agropyron cristatum Growth and Clonal Reproduction to Temperature,Moisture and Clipping

作　　者：韩鸿昆 刘军 屈璐昊 徐佳 杨季云[2] 白龙[2] HAN Hongkun;LIU Jun;QU Luhao;XU Jia;YANG Jiyun;BAI Long(Institute of Grassland and Ecology,Jilin Academy of Agricultural Sciences,Changchun 130033,China;College of Horticulture,Shenyang Agricultural University,Shenyang 110161,China)

机构地区：[1]吉林省农业科学院草地与生态研究所,吉林长春130033 [2]沈阳农业大学园艺学院,辽宁沈阳110161

出　　处：《中国草地学报》2023年第6期44-52,共9页Chinese Journal of Grassland

基　　金：吉林省农业科技创新工程人才基金项目(CXGC2021RCG007);国家自然科学基金项目(31600327);吉林省科学技术厅自然科学基金面上项目(20230101267JC)。

摘　　要：以无性系植物冰草为研究对象,通过综合分析冰草的生物量分配、表型可塑性及光合效率对不同温度、水分、刈割及其交互作用的响应机制,揭示气候变化下草地无性系植物在不同水热环境下的生存策略。结果表明:(1)增温抑制冰草的生长繁殖。增温环境下,冰草株高、生物量、分蘖数均有所降低,仅在水分适中(土壤田间持水量70%)时能够维持叶片数与叶面积不减少;增温中水处理中,冰草可通过提高净光合速率、蒸腾速率及气孔导度来保持光合产物及生物量的积累;中度刈割与70%的土壤田间持水量产生协同效应,可维持冰草光合作用,促进补偿生长。(2)干旱(土壤田间持水量35%)是抑制冰草生长繁殖的最主要因素,所有环境中干旱均使冰草的叶片数、叶面积、分蘖数与生物量显著下降(P<0.05);非干旱土壤(土壤田间持水量70%和100%)常温环境中,刈割促进冰草分蘖,更多的叶片促进光合作用及生物量积累,有利于冰草的生长繁殖;水分过多(土壤田间持水量100%)在常温环境下促进冰草地上生物量积累,在增温环境下反而产生抑制。综上所述,随着气候变暖与土壤干旱,冰草生活力迅速下降,应适时进行水分及刈割调节,缓解环境胁迫对冰草生长与繁殖的抑制作用。In this study,the response mechanism of Agropyron cristatum biomass allocation,phenotypic plasticity and photosynthetic efficiency to different temperature,soil moisture,cutting and their interactions was analyzed,the survival strategies of grassland clonal plants in different soil hydrothermal environments under climate change were revealed.The results showed that:(1)Warming inhibited the growth and reproduction of A.cristatum,with decreased plant height,biomass,and tiller number under warming conditions.Only when the soil water content was moderate(70%of the field water capacity),the leaf number and leaf area of A.cristatum could be maintained.Under warming and moderate soil water content conditions,A.cristatum could maintain the accumulation of photosynthetic products and biomass by increasing the net photosynthetic rate,transpiration rate,and stomatal conductance.Moderate cutting had a synergistic effect with 70%field water capacity,which could maintain photosynthesis of A.cristatum and promote compensatory growth.(2)Drought(35%field water capacity)was the main factor inhibiting the growth and reproduction of A.cristatum,with a significant decrease(P<0.01)in leaf number,leaf area,tiller number,and biomass in all environments.Non-drought soil(70%and 100%field water capacity)under normal temperature conditions promoted tillering of A.cristatum,and more leaves promoted photosynthesis and biomass accumulation,which were beneficial for its growth and reproduction of A.cristatum.Excessive moisture(100%soil moisture capacity)promoted the accumulation of aboveground biomass on A.cristatum under normal temperature conditions,while it actually inhibited the accumulation of aboveground biomass under warming conditions.In summary,with the intensification of climate warm‐ing and soil drought,the vitality of A.cristatum decreases rapidly.It is necessary to adjust soil moisture and cutting in a timely manner to alleviate the inhibition effect of environmental stress on the growth and reproduction of A.cristatum.

关 键 词：冰草 增温 土壤干旱 刈割 生长 繁殖 

分 类 号：S543.9[农业科学—作物学]