Abstract
The objective of this study was to evaluate the performances of three cassava genotypes on yield, physiology and morphological traits under different fertilization regimes. A field experiment was conducted in a split-plot design for two consecutive seasons in the Mansa district of the Luapula Province of Northern Zambia in the highly weathered Chromi-haplic Acrisol soils. Four fertilization regimes, control-M3, lime-M1, NPK fertilizer-M4 and NPK fertilizer + lime-M2 were the main plots, while three varieties (Mweru-V1, Bangweulu-V2 and Katobamputa (local)-V3) were subplots. Periodic measurements of leaf area index, light interception, yield and yield components from 75 days after planting (DAP) up to 410 DAP and daily weather measurements of data were recorded. Fertilization significantly increased the radiation use efficiency (RUE) and light extinction coefficient (K) in two seasons compared to the control. Significant fertilization regimes and varietal effects were observed for seasonal LAI, stem yield, root yield, biomass, harvest index (HI), tuber number, root diameter, plant height and SPAD (chlorophyll index). A significant year’s effects on root yield, yield components and physiological performances were observed while significant fertilization × variety interaction was observed on seasonal LAI, tuber number, root diameter, plant height and SPAD. Significant fertilization × year interaction effects were observed on root yield, yield components and physiological performances. Variety × year interaction was significant for seasonal LAI, stem yield, harvest index and plant height and no three-way interactions were observed on all the traits. NPK fertilizer + lime and NPK fertilizer treatments may be adopted to increase the response of cassava varietal yield, physiology and morphological traits in low soil nutrient conditions under high rain-fed conditions.
Highlights
Introduction conditions of the Creative CommonsYield differences between attainable yields and farmers’ actual yields are huge for cassava in Zambia [1]
Stem yield is highly influenced by root yield, leaf matter, SPAD, harvest index (HI), plant height (PH), root diameter, mean leaf area index (LAI), tuber number and radiation use efficiency (RUE)
This study showed that applying NPK fertilizer + lime or NPK fertilizer only treatments significantly resulted in higher yield when compared to lime or the control in cassava cropping systems
Summary
Introduction conditions of the Creative CommonsYield differences between attainable yields and farmers’ actual yields are huge for cassava in Zambia [1]. A major limitation for cassava productivity is inherently low soil. Manioc (Manihot esculenta Crantz), is a low input crop with the ability to yield well in adverse environments with low fertility and acidic soils where other crops failed [3,4]. The northern part of Zambia is characterized by highly weathered, leached soils with extreme acidity where crop production is dominated by cassava [5]. Cassava yield is limited by the availability of nitrogen (N) phosphorus (P) and potassium (K). Recent studies report that a sufficient supply of potassium (K) and nitrogen (N) is critical for yield stability and productivity [6]. Availability of K is critical for cassava bulking and substantially limits cassava root yield if the crop is repeatedly grown without adequate fertilization due to the large export of K in the harvested tubers [7]. Low organic matter may limit nitrogen, affecting plant canopy development for cassava [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
