Preparation Of Copper-based Foliar Fertilizers And Its Effects On Growth And Disease Control Of Grape,celery And Eggplant

Grape,celery,and eggplant are the main fruits and vegetables in China.Downy mildew,gray mold and other diseases are easy to occur in their growth,which are controlled by copper fungicides.Up to now,there are many kinds of copper fungicides sold on the market.But there are also many problems with copper fungicides,such as unstable effect,the imperfect production technology and the serious soil pollution.Therefore,it is urgent to use novel copper fungicides which have better bactericidal activity,low toxicity and no pollution to the environment.Copper-based foliar fertilizers,produced by National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources,Shandong Agricultural University,had roles of sterilization and nutrition.They are novel copper suspending agents which were based on the traditional Bordeaux mixture and added with iron,zinc,boron,calcium and other nutrient elements.Anionic surfaceactive agent,wetting agent and dispersing agent were also added to improve utilization efficiency.Elucidating the mechanisms for increasing yield and the effect of application of copper-based foliar fertilizers can provide strong theoretical support for the popularization and application of copper-based foliar fertilizers in fruits and vegetables.A two-year?2014-2015?field experiment was conducted with a high-yielding cultivar‘kyoto'in the Yellow River Delta of China in order to investigate the effect of copper-based foliar fertilizer combined with chelate iron?Cu-Fe?on the growth and yield of grape.Similarly,to explore the impact of copper-based foliar fertilizer combined with zinc and boron?Cu-ZnB?and copper-based foliar fertilizer combined with chelate calcium?Cu-Ca?on the growth of celery and eggplant,potted experiments were conducted in Shandong Agricultural University.A pot experiment was conducted at an intelligent greenhouse to investigate the leaching rate of copper-based foliar fertilizer?CBFF?on eggplant leaves and its effects on disease control of gray mold,yield,biomass,available copper content and total copper content in soil under simulated rainfall intensity.The main results were as follows:?1?The process and product test of copper-based foliar fertilizer combined with chelate iron which produced by horizontal sand millThe grinding time of horizontal snad mill was 30 min under the stationary grinding medium,feed rate and slurry proportion.Under this condition,the particle size D50 and D97of product were 2.65 and 11.09?m,respentively,with the specific surface area 1481.30m²·kg^-1,pH 8.23,and the suspenison percetage more than 70%.The results of fourier transform infrared spectroscopy,XRD pattern,SEM images,and EDX spector and maps revealed that Cu?OH?₂ and chelate iron?EDDHA-Fe?were combined stably.?2?Effects of foliar application of copper-based foliar fertilizers on the yield,quality,and disease index of table grape,celery and eggplantGrape yield sprayed with 1.0 g·L^-1 Cu-Fe was 10.1-10.2%,7.5-9.7%,and 2.6-3.7%higher than the Control,BDM,and 1.0 g·L^-1 CBFF treatments,respectively,across the two-year test.Sprayed with 1.0 g·L^-1 Cu-ZnB?Cu-ZnB1?significantly increased celery yield by 18.6-20.4%,13.8-14.8%and 4.5-5.5%,compared with Control,BDM and 1.0 g·L^-1 CBFF respectively,in the two growth seasons.In the grape harvest stage of two seasons,disease index sprayed with 1.0 g·L^-1 CBFF and 1.0 g·L^-1 Cu-Fe was decreased by 32.6-40.9%and28.9-33.3%,respectively,compared with BDM treatment.The disease index of celery in Cu-ZnB1 was significantly decreased by 77.1-79.0%and 45.5-49.3%compared with Control and BDM treatments at 120 DAT.In the experiment of eggplant,compared with water and BDM,the yield in the treatment sprayed with Cu-ZnB was increased by 12.3%and 8.6%,and the treatment with Cu-Ca was increased by 10.0%and 6.4%;the yield of eggplant in CRK treatment was increased by 6.8%compared with potassium chloride treatment?K?.Disease index of Cu-ZnB and Cu-Ca treatments were significantly decreased by 27.4-30.9%compared Control and CRK treatment decreased disease index by 16%compared to KCl treatment.Treatment sprayed with 1.0 g·L^-1 Cu-Fe significantly increased soluble solid,vitamin C,soluble sugar contents and sugar acid ratio,compared to Control and BDM treatments.Cu-ZnB1 treatment increased soluble solid and vitamin C content and reduced nitrate content of celery and eggplant fruits.?3?Effects of foliar application of copper-based foliar fertilizers on the plant and soil nutrient element concentrationThe Fe concentration of leaves in Cu-Fe treatments were increased markedly by20.1-48.6%compared to other treatments and the leaf SPAD value,chlorophyll content and photosynthetic indices were all markedly increased by spraying Cu-Fe,owing to its improved wettability and uniformity to grape leaves than others.In Cu-ZnB1 treatment,Zn content of celery leaves was significantly increased 17.6-49.6%and B content was improved by10.6-15.2%,compared with Control,BDM and CBFF1.Also,Cu-ZnB1 treatment significantly increased SOD,POD and CAT activity and decreased MDA content of celery leaves,compared with other treatments.Ca concentration of leaves with Cu-Ca sprayed was significantly increased by 22.7%and 22.8%compared with Control and Cu-ZnB treatment and decreased by 5.8%compared with BDM treatment.Cu concentration of grape,celery,and eggplant leaves sprayed with CBFF,Cu-Fe,Cu-ZnB,and Cu-Ca was significantly decreased compare with the BDM treatment.As results of surface tension and contact angel on the leaves of the whole copper-based foliar fertilizers,available Cu concentration sprayed with CBFF,Cu-Fe,Cu-ZnB,and Cu-Ca were significantly decreased in the 0-20 cm soil depth of 2015 and in the soil of celery and eggplant pots,compared with BDM.Hence,application of copper-based foliar fertilizers could decrease Cu accumulation in plants and soils compared with traditional Bordeaux mixture.?4?Effects of copper-based foliar fertilizer on eggplant growth and disease Control under simulated precipitation conditionThe results showed that the surface tension of CBFF was decreased by 37.0%and 33.4%respectively,compared with the surface tension of deionized water and traditional Bordeaux mixture.The contact angles between CBFF and eggplant leaves were decreased by 28.1%and31.2%compared with that of deionized water and BDM.At the seedling stage,initial flowering stage and fruit stage of eggplant,compared with the BDM treatments,the leaching rates on eggplant leaves in CBFF treatments under the simulated rainfall intensity of 17.1mm·h^-1 were significantly decreased by 33.2%,10.2%,and 32.0%,respectively;the leaching rates under the simulated rainfall intensity of 33.7 mm·h^-1 were decreased by 19.3%,15.2%,and 19.2%,respectively;the leaching rates under the simulated rainfall intensity of 58.7mm·h^-1 were decreased by 15.5%,11.5%,and 20.9%,respectively.At the fruit stage,compared with BDM treatment,the disease control effect of CBFF treatment on gray mold was increased by 51.6%under no rainfall situation;the control effect on gray mold of the CBFF application under the simulated rainfall intensity of 33.7 and 58.7 mm·h^-1 increased by70.8%and 181.0%.The use of CBFF also significantly increased the plant height,stem diameter and biomass of eggplant at fruit age of eggplant.At fruit stage,under no rainfall situation,the available copper content in soil sprayed with CBFF was remarkably reduced by18.8%when compared with BDM treatment.But for the total copper content in soil,there were no significant difference among all those treatments.Under the simulated rainfall intensity of 17.1,33.7,and 58.7 mm·h^-1,CBFF significantly decreased the available copper content in soil by 23.9%,41.8%,and 45.3%,respectively,and also decreased the total copper content of soil by 4.3%,9.1%,and 18.0%,compared with BDM treatment.These results demonstrate that spraying with CBFF on the leaves of eggplants under the simulated rainfall intensity of 17.1,33.7,and 58.7 mm·h^-1 not only significantly decreases the leaching rate of protective agent,promotes the control effect of gray mold and increases the yield and biomass of eggplant,but also reduces the accumulation of copper in the soils.