Microstructural,Physiological And Biochemical Analysis Of Two Potato(Solanum Tuberosum L.)Clones Under Drought Stress

Drought is the major abiotic stresses that impact plant growth and reduce the production of crops.The mechanism of plant drought resistance is a very complicated reaction process.Plant have evolution produced a wholeset of drought resistance mechanism,including morphological characteristics changed,physiological and biochemical and anatomical structures have changed under drought stress.Roots system play an important role for absorbing nutrients and moisture from the soil and supporting for the vital organs growth.In this study,the different drought resistance two potato materials was planted in PVC pots under natural conditions.Here we examined the microstructure alteration,physiological responses in potato(Solanum tuberosum L.C16:CIP397077.16 and C19:CIP398098.119)materials to gradient water stress with three times continuous observations(15,30,and 45 days after drought,respectively),in combination with the comprehensive drought resistant coefficient(CDC),comprehensive drought resistant index(CDI),membership function values(CDM)and drought resistance of comprehensive evaluation values(D).The main results of this study were as follows::1.The C119 comprehensive drought resistant coefficient(CDC),comprehensive drought resistant index(CDI),membership function values(CDM)and drought resistance of comprehensive evaluation values(D)were higher than C16,which indicated that C119 drought resistance stronger than C16.The developed root system potato C119 material have a strong drought resistance that drough have an small effect on it.2.Plant height,stem diameter,chlorophyll content,root activity,water content of stem and leaf of C119 were lower than C16.The developed root system of potato was strong drought resistance,and the impact of drought stress was small in the drought conditions.The C16 of MDA content were higher than C119.Compared two variety potato of activities with control antioxidant enzymes that SOD,POD and APX were higher.The activities of C16 antioxidant enzymes including SOD,POD and APX were higher than C119.3.The results of the morphological changes of two potato varieties leaves and roots under drought stress showed that fence tissue cells found deformation,the space becomed loose,the epidermal cell size was irregular,the cell space gap becomed larger,and the thickness of the sponge tissue increased first and then decreased.The higher root system of C119 thickness,palisade tissue and spongy tissue thickness were higher than C16,the roots developed a higher degree of potato varieties under drought conditions by increased the thickness of palisade tissue and improved the rate of utilization of energy and water storage capacity of leaf,enhanced the efficiency of photosynthesis.With the increased of the thickness of C119 root endodermis and the decrease of the thickness of cortical parenchyma,the root water uptake capacity was enhanced,thus potato with higher root system had stronger adaptability and resistance for drought.