This study was carried out during 2015 and 2016 seasons to examine the effect of spraying chitosan at 0.25 to 1.0% once, twice or thrice on growth, nutritional status of the trees, yield and fruit quality of Succary mango trees grown under Aswan climatic conditions.
Treating the trees once at growth start, twice at growth start and just after fruit setting or thrice at the same previous two dates and one month later with chitosan at 0.25 to 1.0% substantially improved all growth again aspects, chlorophylls a & b, total chlorophylls, total carotenoids, N, P, K, Mg, Zn, Fe, Mn, fruit retention %, yield and both physical and chemical characteristics of the fruits relative to the control. The promotion was related to the increase in concentrations and frequencies of application of chitosan. All the investigated parameters were unaffected with increasing concentrations from 0.5 to 1.0% and frequencies of applications from twice to thrice
Conclusively, the best results with regard to yield and fruit quality of Succary mango trees grown under Aswan climatic conditions were obtained due to treating the trees twice at growth start and again just after fruit setting with chitosan at 0.5%.