Effects Of Simulated Drought Stress On Growth And Microtuber Yield Of Potato Plantlets In Vitro

Using the plantlets of Varieties Kexin 1,Shepody,K1 and K2 as experimental mateial,the effects of drought stress on potato seedling growth and micro tuber formation were determined by supplying different concentrations of mannitol and sorbitol in the culture media.The experiments were performed from 2015 to 2016 and the results showed as follows.1.The leaf numbers and plant heights decreased with drought stress increase for all potato varieties,the same as the water content in all organs.However,with the increase of drought stress the root dry matter increased first and then decreased,especially for Varieties K1 and K2.It shows thatal though common in the changes of the morphological index and biomass of different varieties suffered from drought stress,the changes of root biomass were different among varieties,which are visual differences of drought resistance of potato varieties.2.The solube sugar of most potato varieties decreased when suffered from drought stress.However,its contents in the stem of K2 variety is highest under 0.1mol/L mannitol treatment.The starch content in different organs was decreased first and then increased under drought stress.3.It is different on micro tuber time under the drought stress.The tuberization was earliest under 0.1mol/L mannitol and sorbitol compared with other treatments.The total numbers of tuber and the rates of medium and large tuber decreased with the increase of drought stress concentrations.