Biological Response Mechanism For The Interaction Between Nitrogen And Planting Density Of High Yield Peanut Variety

The high-yield peanut cultivars need reasonable canopy structure and scientific fertilization to give full play to its yield potential. As a newly rised peanut production area, it is necessary for Liaoning province to deeply research the suitable fertilizer and density level and the field configuration of high-yield peanuts, In this study, using high yield peanut cultivars as materials, root system growth of high-yield peanut under interaction between fertilizer and density, relationship between nutrient absorption pattern and yield, identify the suitable fertilizer and density interaction form of Liaoning high-yield peanut were done under field condition trials. On the base of the former researches, population physiological response mechanism on reasonable fertilizer and density planting high-yield peanut was discussed, and the field configuration form to fully express high-yield potential of high-yield peanut was formed. Main results as follow:1. High-yield peanut varieties’root change morphologically and physiologically under interaction between fertilizer and density. Specific root length, root vitality and kernel yield has a significant positive relation with correlation coefficient0.715**and0.556*respectively. Among them, N2M2and N2M3show a better result with bigger specific root lengh and stronger root vitality.2. Interaction between fertilizer and density has a certain effect on peanut yield. Among9treatments, N2M2(N-input105kg, density150thousands points per ha,2grain per pot) reaches the highest with a population yield7205.55kg·hm-2, followed by N2M3(N-input105kg·hm-2, density180thousands points per ha,2grain per pot) with a yield of6828.60kg·hm-2. Both treatments show a well-growth root system, strong ability to uptake the nutrient, which is propitious to good intake and utilization of nutritient for peanut population. They also show a better canopy structure, higher light energy efficiency, and a balanced growth between top and root.3. A model to anticipate yield on the base of peanut leaf nutrient content was founded by analysis of relation between peanut yield and leaf nutrient content during seedling, pegging, pod-setting and pod-filling stage. The coefficient of determination (R2) of the multiple linear regression(MLR) model is0.982, and Standard error of estimate(SEE) is176.129kg/hm2. This model can be a technic to precisely anticipate peanut yield, and providing a diagnosis basis for assuring the amount and the date of top dressing.4. The Crop Growth Rate (CGR) has a significant positive relation with Leaf Area Index (LAI) and Pod Growth Rate (PGR) in earlier stage, while a significant negative relation with LAI in middle stage, and a significant positive relation with population Net Assimilation Rate (NAR) and PGR in later stage. A larger LAI in earlier stage is propitious to dry matter accumulation in earlier stage and to promote pod growth earlier. A smaller LAI in middle stage is propitious to improve leaf net assimilation rate and hense increase the speed of plant and pod growth. The result in this experiment shows that earlier flowering time and more flower number, small LAI of upper plant, average distribution of leaf area are the physiological basement for a dense-planting population to gain a higher yield.5. Different field configuration forms were compared to analyze their effect on high-yield peanut population photosynthetic physiological parameter, yield and yield related traits. Results show that, the LAI, population net dry matter accumulation amount, photosynthetic potential, population transparency rate and CGR of two rows in one wide ridge is higher than one row in one narrow ridge and three rows in one wide ridge. Kernel rate, hundred nut weight and nut yield show a same tendency. Peanut population get a suitable structure configuration, can use light more efficiently and reach a higher yield under cultivation form of two rows in one wide ridge.