Suitable Soluble Fertilizer Amounts And Periods Of Peanut Under Drip Fertigation And Its Physiological Effects

In order to explore the suitable soluble fertilizer amounts and periods of peanut under drip fertigation and discuss its physiological effects,field experiments were conducted by setting different amounts?Pure nutrient amounts,90⁹00kg/hm²?and different proportion of fertilization in each periods?apply 20%⁸0% of fertilizer in pod-pin stage,average apply residual fertilizer in pod formation and pod filling stage?to research the effects on growth of plants,physiological characteristics of leaves,yield,quality,fertilizer use efficiency and economic benefit of different treatments.The main findings were as follows:1.Effect of soluble fertilizer amounts on growth,physiological characteristics of leaves,yield and quality and nutrient uptake of peanut.Main stem height,side-branch length,above-ground biomass,yield increased as the increase of fertilizing amount when soluble fertilizer amounts were between 90⁵40 kg/hm².When applied 360kg/hm² soluble fertilizer,yield reached a high level,pod yield increased 7.52%,kernel yield increased 16.65% compared with traditional fertilization;continue to increase the amount of fertilizer,main stem height,side-branch length,stems+ leaves biomass increased significantly but the yield increasing was not significant;When applied over 720kg/hm² soluble fertilizer,yield was reduction.Under the same nutrient application condition?360kg/hm²?,yield of peanut increased significantly by higher pods number and kernel rate;on the other hand,it also increased the antioxidant enzyme activity,soluble protein content and SPAD value of leaves and decreased the MDA content of leaves during yield formation period,which delayed the senescence,shedding of the leaves,and prolonged illumination time.The distribution of nutrient in pods and fertilizer use efficiency was also higher when applied 360kg/hm² soluble fertilizer.2.Effects of different proportion of fertilization in each periods on growth,physiological characteristics of leaves,yield and quality and nutrient uptake of peanut.Increasing fertilization proportion in pod-pin stage was beneficial to promote the vegetative growth of the plant.Increasing fertilization proportion in pod formation stage and pod filling stage moderately promoted the reproductive growth of plants more,and it could also delay the decrease of green leaves number and SPAD value in the later growth stage,increase the content of soluble protein,decrease MDA content of leaves,delay the senescence of leaves to prolong the light time.Yield,quality of seed and fertilizer use efficiency reached maximal value at the same time when applying 60% soluble fertilizer in pod-pin stage,and 20% each in pod formation stage and pod filling stage.At this time,pod yield increased 7.82%,kernel yield increased 18.33% and fertilizer use efficiency increased 21.51% compared with traditional fertilization.3.Economic benefits of peanut under drip fertigation.When the amount of soluble fertilizer was 180kg/hm²,the economic benefit was the best,and when the amount of soluble fertilizer was 360kg/hm²,applying 60% in pod-pin stage,and 20% each in pod formation stage and pod filling stage benefited the most.The negative effect from high cost of soluble fertilizer exceeded the positive influence from income of kernel became to the main limiting factor to improve the economic benefit of peanut under drip fertigation.4.Suitable soluble fertilizer management scheme of peanut under the condition of drip fertigation.When the effective nutrient content of soluble fertilizer?N: P₂O₅: K₂O = 20: 20: 20?was in the range of 180³60kg/hm²,and apply 60% in pod-pin stage,20% each in pod formation stage and pod filling stage under drip fertigation,pod yield,fertilizer use efficiency and economic benefits of peanut can reach a higher value at the same time,to achieve the purpose of saving fertilizer and efficiently production.