The Effect Of Plant Growth Regulators On The Growth And Yield Of Peanuts

The ideal plant type and coordinated metabolic relationship play an important role in the formation of peanut yield.The experiment was carried out from 2016 to 2017 in the No.7 test site of the 8th operation area of Heping Ranch in Daqing City,Heilongjiang province to study the relationship between plant growth regulators and peanut growth and development,physiological metabolism and yield.The�Sili'peanut cultivar was used as test material,and three different kinds of plant growth regulators including amine fresh ester?DTA-6?,gibberellin?GA3?,kinetin?KT?were chosen to use in the field experiment.By screening and mingling of various concentrations of plant growth regulators to study the effects on peanut growth,photosynthetic characteristics,physiological metabolism and yield.The aim of this study was to find the optimal concentration of regulator and to increase the yield of penuts.The main findings are as follows:1.Different concentrations of plant growth regulator DTA-6,GA3 and KT significantly promoted the dry matter accumulation of peanut leaves,stems,roots and pods,and increased the yield.The optimal concentration for DTA-6 was 40 mg/L and KT was 30 mg/L.The increase rate can reach 29.65%compared to CK group when application DTA-6 at the rate of 40 mg/L.On this foundation,the level of dry matter accumulation and yield reached maximum when the combination of S₃₃₀₇?30 mg/L?and DTA-6?60 mg/L?were applied to peanut,and the yield was higher than the treatments of S₃₃₀₇?30 mg/L?,DTA-6?40 mg/L?or CK,and increased by 23.68%,20.19%,35.57%.2.Different concentrations of plant growth regulator DTA-6,GA₃ and KT could increase net photosynthetic rate,stomatal conductance and intercellular CO₂ concentration of peanut leaves,enhance photosynthesis of peanut plants,increase transpiration rate and water use efficiency of leaves,promoting leaf water metabolism,and both photosynthesis and water metabolism index showed an increasing trend with the increase of application concentration.DTA-6 concentration at 60 mg/L and 40 mg/L increased net photosynthetic rate,stomatal conductance,leaf transpiration rate and water use efficiency by 238%,210%,144%and 38%respectively compared with CK.3.Different concentrations of S₃₃₀₇307 and DTA-6 promoted the leaf carbon and nitrogen metabolism,and significantly increased the leaf starch contents,soluble protein contents,nitrate nitrogen and free amino acid contents.Antioxidant enzymes activity,SOD,POD and CAT were increased,however,the MDA content decreased in leaves.The most prominent combination concentration were 30 mg/L for S₃₃₀₇,and 60 mg/L for DTA-6 or 60 mg/L for S₃₃₀₇,and 20 mg/L for DTA-6.4.Different concentrations of mixed S₃₃₀₇307 and DTA-6 agent significantly improve the main stem diameter of peanut plants,promote the growth of peanut side branches,and increase the number of peanut branches,the optimal concentrations for S3307 is 30 mg/L and DTA-6 is 40mg/L.The largest number of flowers was found when the concentrations for S₃₃₀₇307 is 60 mg/L and DTA-6 is 20 mg/L.