Study On The Defoliation Cause And Improvement Measures Of Ficus Microcarpa L. F. During Storage And Transportation

Storage and transportation is a necessary period for exporting Ficus microcarpa L.f.,and it can impact Ficus microcarpa′s ornamental value exactly whether measures of storage and transportation is good or bad.According to the problem that the leaves of Ficus microcarpa shed during storage and transportation,which effects its ornamental value.This experiment chose grafted Ficus microcarpa as test material,used theory of environment stress impacting plants' growing and metabolism,having observed leaves' ultrastructure and chosen lowest critical temperature and antistaling agent,designed orthogonal tests considering factors of temperature, antistaling agent,packaging methods,and Chose 10℃,13℃and 16℃;Chose 5mg/L KT,600mg/L 0.1 %brassinolides,500mg/L aspirin as antistaling agent factor;Chose 1%Xian-liang wax,0.03mm polyethylene film,no packaging as packaging methods factor.Analyzed data with DPS software,studied the defoliation and weight loss rate and the changing rule of physiological and biochemical metabolism including antioxidant system,carbohydrates,endogenous hormone and so on during storage and transportation,and chose the optimum combination of improving Ficus microcarpa′s ornamental value after storage and transportation,and found the principal factor that effected Ficus microcarpa′s commodity quality,so it would as reference basis for implementing the technology of storage and transportation.The main results were as follows:1 Observed with optics microscope,there were stomas in both the upside and downside epidermises of young leaf,but only in downside epidermis of old leaf.Compared the down side epidermises of young and old leaf,we found that stomas in downside epidermises of young leaf were smaller and more,and that in old leaf were bigger and fewer.These differences of structure could make young and old leaves differ in respiration and transpiration and so on physiological metabolism during storage and transportation.2 Made olefin slice using leafstalk and scanned by electron microscope,we found that the cells in parenchyma of young leafstalk were bigger,but that of old leafstalk smaller and more.It is maybe caused by that old leafstalks senescence and generate abscission zone.The vascular bundle in young leafstalk was more regular and closer than that in old leafstalk.These differences indicated that the supporting force of old leafstalk weakened more than that of young leafstalk and exfoliated more easily. So the structure of young leaf could be more adaptive for the bad storage and transportation condition.3 The simulation test under 6℃,8℃,10℃condition showed that Ficus microcarpa could be injured by chilling during storage and transportation at 6℃,and the recovery speed of growth vigor at 8℃was less than at 10℃,so 10℃was the lowest critical temperature for Ficus microcarpa during storage and transportation.Using reagents to Ficus microcarpa based on the production storage and transportation condition,We found that effect of 5mg/L KT and 600mg/L 0.1%brassinolides are best, their defoliation rate were 20.96%,35.48%,and reduced 59.80%,31.97%than CK,and the 10mg/L 6-BA and 500mg/L aspirin were better,but the effect of spermidine was not obvious.The changes of these physiological and biochemical indexs showed that Ficus microcarpa was aging,so senescence was the direct cause of defoliation.4 During storage and transportation of the orthogonal experiment,the defoliation rate was increasing gradually,the content of water,chla,chlb,chl and Car of the leaf in Ficus microcarpa fell, and so fell the ratio between Chla and chlb,however,the ratio of Car and Chl went up.the activity of CAT of Ficus microcarpa′s leaf fell rapidly,the activity of SOD went up first and then fell,the activity of POD went up all the time.Meanwhile,after storage and transportation 14days the content of MDA and REC went up rapidly,electrolytic leaks,and enhanced the cell membrane.The content of starch, sucrose,fructose fell all along,but the content of total soluble sugar went up first,after storage and transportation it began to fall.The content of ABA of the leaf in Ficus microcarpa showed rising trend, and the GA₃ decreasing tendency.5 It was found from orthogonal experiment that 13℃,1%Xian-liang wax,5mg/L KT or 13℃, 1%Xian-liang wax,600mg/L 0.1%brassinolides were optimum combination.They could reduce the activity of protective enzyme' falling speed,delay and reduce the falling of carbohydrates content,and delay the content of MDA and REC to go up and delay and reduce the falling of content of ABA and GA₃,improve Ficus microcarpa′s ornamental value obviously.We obtained conclusion that reagent was the principal factor that effected Ficus microcarpa′s defoliation rate,and temperature was second,0.03mm polyethylene film was the principal factor that effected Ficus microcarpa′s water loss rate,and temperature was the principal factor that effected Ficus microcarpa′s changes of photosynthetic pigments,protective enzyme,carbohydrates,ABA and GA₃.