Abstract:
The objective of the research was to investigate the effects of irrigation levels,
poultry manure (PM), cow dung (CD), NPK and their interactions on the
growth and yield, quality and shelf life of Orange Fleshed Sweet Potato
(OFSP) in evaporative cooling structures. Sixteen treatments (four levels of
irrigation and four soil amendments) with three replicates were laid out in a
Randomized Complete Block Design (RCBD). Irrigation levels did not
significantly influence soil physical properties studied (bulk density, pore
volume and particle density). Water stress (application of 70 % CWR)
increased root yield, water use efficiency, marketable root yield, jumbo root
yield and number of roots per plant as compared to full irrigation while growth
of leaves, branches and dry matter content were reduced. Soil amendment
significantly improved root and marketable yield better under reduced
irrigation (70 % CWR) than under full irrigation. PM, CD and NPK
significantly increased marketable yields by 40.96 %, 30.34 % and 21.36 %
respectively as compared to the control. Cool chamber evaporative structure
(CC) reduced root percentage shrinkage, decay, weight loss and weevil
infestation in storage while sprouting increased. Soil amendment significantly
reduced percentage root decay. Reduced irrigation increased carotenoid and
fibre content while sugar content of roots was decreased. Storage in
evaporative cooling structure increased the percentage content of sugar, starch,
fat, and phenol of roots while fibre, protein, and ash were reduced after 13
weeks of storage.
