Response Characteristics Of Different Strawberry Varieties During Water Stress

Strawberry (Fragaria ananassa Duch.),one of perennial herb temperate fruit trees with high nutritional value,earned the name"Queen of fruits". However, because of shallow root system, larger leaves, strong transpiration, it is easy to cause water deficit under drought conditions, and which has a serious impact on strawberry production and quality.with annual Aiersangta, stars, the generals, Opel, a ghost angrily Gan, Maria, red Ruiguang as material, the growth, physiological and biochemical indicators were studied with persistent drought in the field circumstances, to discuss the drought-resistant mechanism of strawberry and to establish drought resistance evaluation index system and to provide scientific and theoretical basis for further studies of the drought-resistant varieties breeding and cultivation production.Water stress seriously affected the growth of strawberry plants. as the time went, the root-shoot ratio was increased, Opel increased 38.6 percent which was the largest among seven strawberry varieties, while the general increased 17.0 percent which was the lowest among seven strawberry varieties.With the strengthening of water stress, the chlorophyll content, net photosynthetic rate,stomatal conductance, transpiration rate and intercellular CO2 concentration of seven kinds of strawberries dropped. When the srawberry met with severe stress, the above indicators dropped to the lowest level, of which the most obvious one is the general,its net photosynthetic rate dropped by 90.11 percent,and Opel fell 69.30 percent. After Rehabilitation of water, the above indicators are several different levels of increase, but have not reached the level of control.With the extension of water stress, the proline, soluble sugar, soluble protein content of strawberry leaves increased; MDA content increased too, which caused permeability of cell membranes increas nad made cell injury; the performance of SOD and POD activity lowered after increasing. But different varieties SOD, POD increasement and activity was significantly different. After rehabilitation of water -SOD, POD activity decreased.With the increase of water stress, strawberry endogenous hormone contents have greater changes, ABA content increased, IAA, ZR and GA3 declined. ABA content of Opel and Elsanta showed rapid increase, the generals, All stars and a ghost angrily dry turned on fast - slow - fast rising trend. IAA, ZR and GA3 of different species declined differently, Opel decreased faster in the pre-growth period, and declined slowly in the latter part, while the general performed contrarily. After rehabilitation of water, the ABA declined, IAA, ZR, GA3 increased.Use of fuzzy math functions method, under drought condition the physiological and biochemical indicators of seven Strawberry were compared, the order of seven strawberry drought-resistant ability was: Opel> Elsanta > Red Ruiguang>All Stars> ghost angrily Gan> Maria> major general.