Effects Of Bagging On Fruit Development And Quality Of Pitaya

Pitaya(Hylocereus)is a kind of newly popular tropical and subtropical fruit,which is mainly cultivated in South China.Harvest time for pitaya is mainly from summer to autumn with high temperature and humidity.Pitayas are easily to be vulnerable to disease and pests during this period which seriously affect the eating quality and commodity value.Bagging is a green,safe,convenient,effective method to produce high quality fruit and to prevent pests and diseases.In this study "Hongguan No.1"(red skin with red flesh)and "Hongbaoshi"(red skin with white flesh)pitayas were used as the material to explore effects of three different fruit bags i.e.black non-woven bag,yellow wax paper bag and black mesh bag on fruit development and quality of pitaya.Difference in fruit coloration,rates of diseases,the appearance and internal quality as well as storage quality were analyzed among the three different fruit bags.The aim of the present study is to screen a suitable bag for pitaya production.The main results were as follows:1.In summer,two days earlier color changing were detected when the pitaya fruits were performed in black non-woven and yellow wax paper bags.Black non-woven and yellow wax paper bags also had a better appearance in term of higher values of L* and a*.In autumn,the optimum bag is black non-woven bag which could make "Hongguan No.1" pitaya 3-5 days earlier color changing,followed by the yellow wax paper bag.No significant difference in mature period was detected between the black mesh bag and control.2.Difference in fruit quality of "Hongguan No.1" was detected between different bagging treatments from summer to autumn.Pitaya weight was increased after bagging of black non-woven bag and yellow wax paper during June to October.However,weight per fruit and fruit diameter were significantly lower than that control(P<0.05)from August to September compared to higher edible rate and lower peel thickness were detected in October.3.Difference in storage quality was detected between different bagging treatments.There are 28 days storage period for control(with bagging)compared to 35 days for bagging treatments.The yellow wax paper bag can improve the total phenol and flavone contents.Higher betalain contents were detected in the presence of black non-woven bag compared to higher TSS contents for black mesh bag and control.4.The black non-woven bag and yellow wax paper bag can prevent dragon fruit from damaging by birds,mouse and flies.The black mesh bag was secondary.However,pitayas are easily to be vulnerable to aphids after bagging in October.Highest aphid infestation rate was detected for yellow wax paper bag(31.6%),followed by black non-woven bag(20.4%),and the lowest(6.5%)was black mesh bag.