Arid Zone Research ›› 2020, Vol. 37 ›› Issue (1): 193-201.

Previous Articles     Next Articles

Expressions of Morphological and Physiological Features of 4 Forage Species under Water Stress and Re-watering Process

ZHANG Jing-ge1, TIAN Fu-ping2, MIAO Hai-tao3, HUANG Ze1, 2, WU Gao-lin1, 3   

  1. 1. Key Laboratory of Soil Erosion and Dryland Agriculture in the Loess Plateau,Northwest A&F University, Yangling 712100,Shaanxi,China;
    2. Lanzhou Institute of Animal Husbandry and Veterinary Medicine,Chinese Academy of Agricultural Sciences/Lanzhou Loess Plateau Key Field Scientific Observation and Test Station of Ministry of Agriculture, Lanzhou 730050,Gansu,China;
    3. Key Laboratory of Soil Erosion and Dryland Agriculture in the Loess Plateau,Institute of Soil and Water Conservation,Chinese Academy of Sciences & Ministry of Water Resources,Yangling 712100,Shaanxi,China

  • Received:2019-03-14 Revised:2019-05-14 Online:2020-01-15 Published:2020-01-14

Abstract: Grassland is one of the main vegetation types in semiarid area. Research on the response and mechanism of forage to soil moisture content is of great significance for the sustainable utilization of water resources and the construction of ecological environment in this area. In this study, four grass species, response of forage morphology, water physiology, photosynthetic and physiological characteristics to water stress and water recovery process in the Loess Plateau were analyzed. The results showed that:   Under water stress, the aboveground morphological indexes (i.e., the single leaf area and shoot dry weight) of the grass species were in a decrease trend, but the underground ones (i.e., the root dry weight and root-shoot ratio) were in an increase trend. After re-watering, the forage morphological characteristics were obviously recovered, and an over compensation of Elymus nutans Griseb. and Lolium multiflorum Lam. occurred;   Under water stress, the water physiological characteristics of forage were significantly decreased, but they were gradually recovered after re-watering and resumed to the level of the control group after 2~3 weeks. These 2 species of leguminous forage could maintain a high water potential and had a strong water conservation capability, which belonged to a delayed dehydration by increasing water potential, and these 2 species of forages belonged to an enduring dehydration by developing low water potential under water stress; Under water stress, the photosynthetic physiological characteristics of forage were also in a significant decrease trend, and the short-term water stress could temporarily improve the photosynthetic capacity of forage; the photosynthetic characteristics of legumes and grasses were different in sensitivity and adaptation mechanism to drought. Leguminous forage closed the stomata in time to avoid drought so as to reduce water loss, while grasses sacrificed leaf water to keep stomata open to maintain normal plant growth.

Key words: forage; water stress, re-watering, morphological characteristic, physiological characteristic