Effects Of S₃₃₀₇ And DTA-6 On The Growth And Yield Of Stevia Rebaudiana

Phytochemical control technology is an important technical measure to improve crop yield.The effects on plant morphology,dry matter accumulation,photosynthetic physiological characteristics,and leaf carbon metabolism of Stevia rebaudiana were studied.The regulator S₃₃₀₇ and the regulator DTA-6 were analyzed.The regulation effect on stevia is to provide a theoretical basis for the regulation effect and action mechanism of regulators S₃₃₀₇ and DTA-6 on stevia.The experiment was conducted in 2017-2018,the dose screening experiment was conducted in 2017,and the pot experiment was conducted in 2018.The pot experiment was conducted using a completely random test method in the pot plant of the National Coarse Grain Technology Research Center in Daqing City,Heilongjiang Province,and the stevia variety Huinong 3 was used as the test material.The experiment is divided into two parts:（1）S₃₃₀₇ root soaking and leaf spraying: S₃₃₀₇ root soaking time is 8 hours before transplanting,the concentration is 0.04 mg/L;S₃₃₀₇ leaf spraying time is 35 d after transplanting,the concentration is 50 mg/L;the control（CK）is a stevia plant without treatment with a regulator.（2）Leaf spray of regulator DTA-6: The leaf spray time was 80 days after transplanting,and the concentration was 60 mg/L;the control（CK）was stevia plants without regulator treatment.The main results of the study are as follows:1.Compared with the control CK,the root soaking treatment of regulator S₃₃₀₇ can obviously promote various morphological indexes of Stevia rebaudiana plants and increase the accumulation of dry matter above the plants.Increased photosynthetic parameters such as chlorophyll content,leaf area index,photosynthetic potential,Pn,E,Gs,and Ci of Stevia rebaudiana.The content of sucrose,soluble sugar,and starch in the leaves were higher than that of the control CK,and the Re A/STV value in the leaves increased significantly,S₃₃₀₇ Compared with CK,the root soaking treatment increased the yield per plant by 27.4%.2.Compared with the control CK,the regulator S₃₃₀₇ leaf spray treatment significantly increased the plant height,stem thickness,number of branches,main stem leaf age and main stem node number,and promoted the accumulation of dry matter above the Stevia plant.Increased the chlorophyll content,leaf area index,photosynthetic potential,Pn,E,Gs,and Ci of Stevia rebaudiana,the content of sucrose,soluble sugar and starch in the leaves were higher than that of the control CK,and the Re A/STV value in the leaves increased significantly compared with CK Compared with CK,the yield per plant increased by 29.9%.3.Compared with the control CK,the regulator DTA-6 leaf spray treatment significantly promoted the morphological indicators such as plant height,stem thickness,branch number,main stem leaf age and main stem node number,etc.The accumulation of dry matter in the above-ground leaves of Stevia rebaudiana plants promoted photosynthetic parameters such as chlorophyll content,leaf area index,photosynthetic potential,Pn,E,Gs,and Ci of Stevia rebaudiana.CK,the invertase activity in the leaves is higher than the control CK,compared with CK,the Re A/STV value in the leaves of stevia plants is significantly increased,and the yield per plant is increased by 32.4% compared with CK.In summary,S₃₃₀₇ and DTA-6 can effectively promote the plant morphogenesis of regulators,increase the accumulation of carbon metabolites and leaf photosynthetic capacity,and thus increase the yield per plant of stevia plants.From the overall performance,the effect of spraying DTA-6 on the leaf yield of Stevia rebaudiana 80 days after transplanting was the most significant.