Effect of time and frequency of topping a bushy sweet potato (VSP-2) on storage root and cutting production [Philippines]
1986
Villamayor, F.G. Jr. | Perez, R.D. (Visayas State Coll. og Agriculture, Baybay, Leyte (Philippines). Philippine Root Crop Research and Training Center)
Using a bushy sweet potato (VSP-2), the effect of topping on storage root and vine cutting production was studied. In the first experiment, all terminal cuttings at least 16 m long were cut either at 38, 45, 52 or 59 days after planting (DAP). The storage root yield was not significantly affected by the time of topping. Meanwhile, the number of cuttings (Y) is related to the time of topping (X) by the equation Y = 0.31X - 9.58 which is significant at 1% level (r = 0.997). In the second experiment, the treatment was the frequency of topping, once to five times. Topping started at 32 DAP and repeated successively at interval of 2 wks depending on the frequency. Only terminal shoots reaching 25 cm long were cut. The number of cuttings produced (Y) is related to the frequency of cutting (X) by the equation Y = 92.37 X - 21.41 which is significant at 1% level (r=0.988). On the other hand, topping significantly reduced yield. The total storage root yield in t/ha (Y) is related to the frequency of topping by the equation Y=18.15-2.12 x which is significant at 1% level (r = -0.953).
显示更多 [+] 显示较少 [-]