The Study On Differences In Physiological Characteristics Of Two Peanut Quality Types

This experiment was carried out to study the differences of physiological characteristics,carbon and nitrogen metabolism enzyme activities of different quality type peanut leaves withchosen high-protein representative varieties of KB008, high oil representative varieties ofH17and aimed to providing the theory of producing high quality special-purpose peanut topeanut quality breeding.This experiment was carried out in the high yield field agricultureexperimental station of Shandong Agricultural university in2012, the main results were asfollows：1Differences in photosynthetic characteristics of two peanut quality typesIn the process of peanut seeds forming, the leaf net photosynthetic rate, phi PS Ⅱ,Fv/Fm, chlorophyll content of two peanut quality types were were showing the change trendthat afte flowering rised firstly then fell,the change trend of intercellular CO2concentrationfirstly lower then rised. after flowering0-45d, net photosynthetic rate, phi PS Ⅱ, Fv/Fm andchlorophyll content of high oil variety H17leaf were significantly higher than the high proteinvarieties KB008, while the intercellular CO2concentration was lower than KB008, afterflowering30d stomatal conductance of KB008was significantly higher; After flowering45d, KB008leaf net photosynthetic rate, phi PS Ⅱ, Fv/Fm, stomatal conductance andchlorophyll content was significantly higher than H17, intercellular CO2concentration waslower than the H17. The prophase and metaphase stages showed that photosyntheticperformance of high oil variety was more higher in the prophase and metaphase,thephotosynthetic performance of high protein varieties was more stronger in the late growthperiod, this maight be related to the formation and accumulation of fat faster and more earlythan the protein in peanut seed kernels.2Differences in soluble sugar and nitrogen content in leaves of two peanut quality typesAfter flowering, the soluble sugar content of two peanut quality types leaf firstly sloweddown, and then gradually increased, at flowering60d reached the peak, then fell rapidly. thesoluble sugar content of high oil variety H17began to increase slowly after flowering30d,and the soluble sugar content of high protein varieties KB008after flowering45d began toincrease, and the increase rate was significantly higher than H17. In the whole growth period, soluble sugar content of KB008leaf was significantly higher than H17, That might be thereason whythe high protein variety were susceptible to pests.The nitrogen content of two peanuts quality types leaf presented the trend of graduallyreducing with advancement of growth period. After flowering0-45d the the reducingamplitude of nitrogen content of high oil variety H17was less than high protein varietiesKB008,after flowering45d, was exceeded KB008. Except for podding period (afterflowering45d), the nitrogen content of KB008leaf belowed H17, the nitrogen content ofKB008leaf was significantly higher than the H17in the rest of the growth period, it showedthat higher nitrogen content of high protein varieties was beneficial to accumulating moreprotein in the seed kernel, That was the material basis for the high protein varietiesaccumulated more protein.3Differences in leaf senescence of two peanut quality typesin the the process of whole growth period, the SOD, POD, CAT activityof two qualitytype leaf tended to rise firstiy,then fell. SOD, POD activity of high protein varieties KB008leaf were significantly higher than that of high oil variety H17in every growth period, H17blade CAT activity15-45d after flowering was higher than the KB008, after flowering45dCAT activity significantly belowed KB008, the MDA content of H17was higher than KB008leaf at every growth period, in the whole growth period, the soluble protein content of KB008leaf was significantly higher than H17. That indicated that the high protein varieties becameaging slower than high oil variety,that was good for the formation and accumulation of theprotein.4Differences in nitrogen and carbon metabolism enzyme activities in leaves of twopeanut quality typesAfter flowering, the NR activity of two peanuts quality types leaf gradually reduced, GSGOGAT activity increased firstly and then decreased.The trend of GDH activity was morecomplex: decreased firstly, after flowering15d reached the minimum, then gradually rised,after flowering45d reached the maximum then slow down. Throughout the process ofgrowth period, the NR GS, GDH and GOGAT activity of high protein varieties KB008leafwere significantly higher than high oil variety H17, but with the process of growth period, thedifference between nitrogen metabolism enzyme activity of two varieties leaf graduallybecame narrow. Overall, during the reproductive period the nitrogen metabolism enzymeactivityof high protein varieties KB008leaf was significantly higher than high oil varietyH17.That showed that the assimilation of nitrogen of high protein varieties leaf assimilationwas more stronger,the assimilation of nitrogen of high oil variety leaf assimilation was more weak, higher nitrogen metabolism enzyme activity was important enzymology basis that highprotein varieties seed kernel protein content was significantly higher than high oil variety.After flowering, SS and SPS activityof two peanut quality types of in presented parabolictrend. SPS and Ru BPC ase activity of high oil varietyH17d leaf after flowering0-45SS, wassignificantly higher than high protein varieties KB008, after flowering45, the SS and Ru BPCase activity of KB008and H17gradually became closed. in the prophase and metaphasestages,the SS, SPS and RuBPC ase activity of higher oil variety was significantly higher thanhigh protein varieties, it was the important physiological basis that high oil seed kernelsynthesis accumulation more fat content.