Effects of Different Types and Rates of Micronutrient Application on Growth, Fruit Yield, Nutritional Value and Phytochemical Components of Pawpaw in Ogbomoso

Abstract

An experiment aimed at investigate the appropriate rates of boron and zinc applications required for optimum fruit yield of pawpaw was carried out at Teaching and Research farm of Ladole Akintola University of Technology, Ogbomoso, Nigeria. The experimental design used was a 2 x 5 factorial experiment in a randomized complete block design and replicated three times. The treatments involved two micro nutrients and five rates of micronutrient which gave ten treatment combinations. The micronutrients were zinc and boron and the rates were 0ml, 10mls, 15mls, 20mls and 25mls in 2021 planting seasons. Seedlings raised in the nursery were transplanted at 12 weeks old. Application of treatments was done at one week after transplanting. These rates were applied to the base of the pawpaw plant according to each treatment combinations. Data collection commenced at point of transplanting and it was carried out at every four weeks interval till twenty four weeks (24 weeks) after transplanting for vegetative growth. At maturity fruits at ripe stages were harvested according to the treatments. Fresh weight of fruits, fruit length and diameter were measured. The fruit qualities were assessed by determining the nutritional composition, mineral physiochemical and phytochemical content of the fruit. Data collected were analyzed by using analysis of variance (ANOVA) by SAS (2009) and significant means were separated using Duncan multiple range test at 5% probability level. The results indicate that boron and zinc had significant effect on the fruit yield, nutritional, and phytochemical properties of pawpaw. Boron gave highest physicochemical analysis (moisture content and pH) while TSS, and Beta carotene were influenced by Zinc application. Mineral elements were also increased by zinc application. It results indicate also that higher quantity of micronutrient produced high quality pawpaw. Keywords: pawpaw, micronutrients, zinc, boron, nutritional, phytochemical. DOI: 10.7176/JBAH/13-4-03 Publication date: March 31 st 2023