Growth performance and nutritional concentrations of two kale (Brassica oleracea var Acephala ) varieties in response to fertilizer types in Awka, Southeast Nigeria

Purpose: Soil nutrient depletion is an endemic factor that constitutes one of the greatest limitations to crop production in the tropics. Identifying high yielding kale varieties that thrive best with the most cost-effective fertilizer type can help meet the nutritional deficits of most families in Africa in line with WHO recommendations. The propose of this study was to determine the effect of fertilizer type and variety on growth, calcium (Ca), iron (Fe), and vitamin concentrations of kale.Method: Two kale varieties, curly and lacinato, and three fertilizers, ۲۰۰ kg ha-۱ NPK ۲۰:۱۰:۱۰ (NPK۲۰۰), ۱۶ t ha-۱ poultry manure (PM۱۶), and ۱۰۰ kg ha-۱ NPK ۲۰:۱۰:۱۰ + ۸ t ha-۱ poultry manure (NPK۱۰۰+PM۸) were evaluated in a ۲×۳ factorial in randomized complete block design (RCBD) with ۳ replications. Data collections were based on selected agronomic, vitamins, and minerals parameters.Results: Fertilizer type, variety and their interaction significantly affected (p<۰.۰۵) agronomic traits, minerals, and vitamin contents of kale. PM۱۶ influenced the most significant increases in plant height, leaf number, Ca, Fe, and vitamin-A concentrations whereas, NPK۱۰۰+PM۸ treated plants recorded higher leaf area and weight. Curly variety showed superiority in leaf area, leaf weight, Fe, and vitamin-A whereas, lacinato was higher in plant height, leaf number, Ca, vitamin D and E. Lacinato variety on NPK۲۰۰ treatment was highest in Ca, vitamin D and E concentrations while curly variety on PM۱۶ was highest in Fe and vitamin A.Conclusion: PM۱۶ and NPK۱۰۰+PM۸ best improved growth, mineral and vitamin concentrations in kale and were therefore recommended for use.

Keywords:

Kale minerals , Vitamins in Kale , Fertilizer type , Varietal effect , Poultry manure