N. 0. Aparra and N. G. Mamicpic
BNAS 51, Centennial and Kinangkong yielded 27.42, 14.32 and 5.41 t/ha of tubers, respectively, with a corresponding coefficient of variation (C.V.) of tuber yield among hills of 41.92, 46.02 and 107.65%. Yield among hills was slightly more uniform at a spacing of 60 x 75 cm (C.V. = 56.39%) than at 30 x 75 cm (C.V. 74.01%), although the difference in variability was not statistically significant. A high C.V. of tuber yield among hills (80.66%) was obtained by applying 200-190-230 kg/ha of N-P205-K20, while a low C.V. (54.81%) was observed at zero fertilizer application. Vine weight, vine number, vine diameter, leaf weight and leaf area were significantly and positively co5rrelated to root yield. Variability in vine weight, vine number and leaf weight were significantly and positively correlated to the variability in root yield.
Annals of Tropical Research 2 (3):(1980)