Yield and nitrogen uptake by cocoyam as affected by nitrogen application and spacing
1981
Igbokwe, M.C. | Ogbonnaya, J.C. (Natonal Root Crops Research Institute Umudike, Umuahia (Nigeria))
Three amounts of N (0, 40 and 80 kg/ha) were tested on cocoyam, Colocasia spp. planted at 80, 60, and 40 x 100 cm at Umudike, Nigeria. Basal dressing of P, K, and Mg were given at 40, 75, and 20 kg/ha respectively. Averaged over all population means, application of N at 40 kg/ha increased yields of corms and cormels by 4.47 t/ha (P=0.05). The largest yield increase of 8.99 t/ha due to N dressing was achieved with 40 kg/ha at a spacing of 100 x 60 cm. But when averaged over all N rates, the mean yields of corms and cormels with respect to the various spacings were not significantly different even though plant heights increased with population density. Observed significant increase in yield due to N was related to an extra 15.3 kg/ha taken up in the tuber when 40 kg/ha was given. This was equivalent to an apparent recovery of 38.3% of the applied N. Tuber yields were more related to the number of cormels than of corms at harvest.
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