The Selection Of Growing Media Of Banana Tissue

Banana is one of the most important economic crops in the tropical and subtropical regions, and is also one of the most important varieties of fruit trees in southern China.The banana planting industry is an important prop industry in Hainan.In the industrial development process,the2nd grade plantlet of seedling production process is an important link related to the banana seedling quality.To find the best ratio of culture substrate of banana’s tissue culture seedling,the study selected Brazilian Banana as experimental object and adopted the orthogonal experiment among the16different proportions of coir-based media with krasnozem,organic fertilizer and sand.The main purpose of this experiment is to provide some theory basis that can promote efficient development of banana industry.The results are as follows:From the growth state treatment13(cocoanut coir dust+krasnozem+organic fertilizer+river sand at a ratio of4:0:0.05:0.1(V/V)) showed the best growth quantity and growth vigor. From the stem diameter,plant height,above ground biomass (dry weight),leaf area of5,6leaf position,refoliation,the spad value of the3d leaf from the bottom up,the leaf length and width of the2d leaf from the top to the bottom,the under ground biomass (dry weight) and root activity respectively,it increased49.78%,49.68%,95.83%,35.18%,12.20%,12.56%,20.44%,23.80%,183.33%and18%than contrast.From the leaf and root SOD,POD activity,it increased52.34%,14.42%,55.63%and6.67%than contrast.From the net photosynthetic rate (Pn),stomatal conductance (Gs),transpiration rate (Tr),intercellar CO2concentration (Ci),PS Ⅱ maximum photochemical efficiency (Fv/Fm),PS Ⅱ actual photochemical efficiency (ΦPS Ⅱ),photochemical fluorescence quenching coefficient (qP) and PS Ⅱ electron transport rate (ETR),it increased17.04%,54.55%,107.83%,7.94%,4.10%,6.29%,18.88%,36.89%than contrast.While at the level of increment of the initial fluorescence (Fo) and coefficient of photochemical fluorescence quenching (NPQ),it reduced14.17%and10.29%than contrast. After the seedling, leaf nutrient of N,P,K respectively,increased94.48%,490.54%,54.86%than contrast.The secondary and trace elements also increased significantly than contrast.The heavy metal of Ni and Cd content in leaves decreased significantly than contrast.After5days of natural drought stress relative to the contrast treatment13(cocoanut coir dust+krasnozem+organic fertilizer+river sand at a ratio of4:0:0.05:0.1(V/V)) which maintained a stable microenvironment did not show a significant stress-induced and therefore had the best drought resistance.From the leaf and root accumulation of proline,water soluble protein,water soluble sugar,membrane permeability and malondialdehyde,it decreased42.34%,31.38%,19.35%,20.53%,34.04%and26.19%,37.96%,48.48%,26.19%,24.62%than contrast.From the substrates aspect,treatment13(cocoanut coir dust+krasnozem+organic fertilizer+river sand at a ratio of4:0:0.05:0.1(V/V)) had batter physical and chemical characteristics than contrast, and it is more suitable for nutrient regulation for lacking of potential nutrient supply.lt decreased86.27%compared to the contrast on bulk density.From total porosity,aeration porosity,water-holding porosity,ratio of large pores and small pores,pH,EC,it increased39.34%,142.86%,25.93%,92.31%,13.81%,103.45%than contrast. And the night thermal insulation performance is better than contrast.The ratio of Exchangeable Al,Mg,Ca to CEC,is0.28,6.91and2.80times of contrast.The content of organic matter,available P,available K,available B,available Zn and total N is increased395.25%,2531.25%,5.82%,146.88%,24.38%,64.29%compared with contrast.The available N,available S,available Cu,total P,total K,total Ca,total Mg,total Mn,total Cu,total Zn,total Fe,total Al,total Ni,total Pb,total Cd are lower than the contrast.With steady performance, the chemical characteristics, available nutrients content and total nutrient content of all substrates during cultivation changed little,the law is not obvious.The nutrient is adequate for seedings.Treatment13(cocoanut coir dust+krasnozem+organic fertilizer+river sand at a ratio of4:0:0.05:0.1(V/V)) have the advantage over contrast in that it put an end to soil borne fungi and nematodes,reduce pesticide use,avoid the nursery environment pollution,prevent soil compaction,conducive to root growth,shorten the field growth slowing seedling,early emergence time,improve germination rate,reduce weight,reduce transportation costs,expand market space,reduce labor input,saving labor costs,increase revenue,meet the requirements of agricultural production,is conducive to the banana intensive management,improve the competitiveness of the banana industry at home and abroad,in line with the objectives of sustainable development in our country.