Farmers' estimates of percent whiteheads (WH)  [1993]

Lazaro, A.A. Rubia, E.G. Almazan, L.P. Heong, K.L. (International Rice Research Inst., Los Banos, Laguna (Philippines))

Access the full text:

A study was conducted to compare farmers' estimates with actual counts of WH [whiteheads] caused by stemborers (SB) in 24 ricefields in Munoz, Nueva Ecija, Philippines in Nov 1992. Farmers equated percent WH to percent yield reduction. They all expected about the same reduction in yield as the WH estimate they had given. An estimate of 30% WH meant the farmer was expecting a yield loss of 30% compared with a season without SB damage. Farmers' estimates compared with actual yield reductions were nonsignificant using t-test. On the other hand, computed percent WH differed significantly from actual reductions in yield. This means that farmers made good estimates of their expected yield losses due to SB. Actual percent damage, however, did not coincide with percent yield reduction, which disproved their statement that percent WH equals percent yield reduction. About 70% of the farmers obtained yield losses greater than actual SB damage. The estimates they gave, however, were fairly close to percent yield loss they obtained. This means that factors other than WH caused greater yield reduction. Farmers attributed these differences to factors such as poor soil, lack of fertilizer, late planting, and unfavorable weather

Other subjects

  • agricultores
  • oryza sativa
  • insecte depredateur des tiges
  • rendement des cultures
  • agriculteur
  • perte de recolte
  • perdidas de la cosecha
  • rendimiento de cultivos
  • insectos daninos del tallo

From the journal

International Rice Research Notes (Philippines)

ISSN : 0115-0944