Identification of IPM for white stem borer (WSB)
Agusan del Norte is endowed with rich soil, favorable climate, and even rainfall distribution throughout the year. Although these features are ideal for rice production, average yield remains low at 3.42 t/ha per cropping season. One reason observed was the constant pest and disease infestation brought forth by asynchronous planting and the occurrence of floods and typhoons. Moreover, since rice was plantede throughout the year, food supply for the insect pests was secured and favored insect proliferation and survival.
To control the infestation of white stem borer (WSB), Scirpophaga innotata Walker, Batay-an et al. (PhilRice-Agusan) developed management practices using planting and sowing dates based onlunar phase and mechanical egg mass removal as IPM options. The options were subjected to economic analyses to determine their profitability. Thestudy was conducted for two cropping seasons per year in 2002-2004.
Findings
- Planting date in Agusan del Norte significantly affected the incidence of WSB. To avoid high WSB damage and increase yield, best planting date for PSB Rc82 and Angelica was December 15 (for November-April cropping season) and July 1 (for May-October cropping season).
- PSB Rc 82 rice variety sown during the last quarter lunar phase had significantly less percent deadhearts (2.15-3.29%) and whiteheads (3.58-15.45%) than those sown during the other lunar phases. This resulted in yields of 4.00-4.28 t/ha compared with the traditional yield of 3.4 t/ha.
- Mechanical removal of egg masses in the field significantly reduced WSB damage (deadhearts and whitehead) which resulted in higher yields of 4.98 t/ha and income of Php42,828 t/ha per season than those of the untreated (4.25 t/ha at Php 36,550 t/ha per season).
- The population of natural enemies was greatly reduced by 49-54% through the application of insecticides.
Cultural methods based on planting date, lunar phase, and mechanical egg mass removal could lead to significant reduction of WSB damage
Source:
PCARRD, 2006. Highlights 2005, Los Banos, Laguna
Organic Farming Information Network
Philippine Council for Agriculture, Forestry and Natural Resources Research
and Development (PCARRD)
©2006