Litsinger JA. 1984. Assessment of need-based insecticide application for rice. Philippine Ministry of Agriculture-IRRI Technology Transfer Workshop March 15, 1984, IRRI, Los Banos, Philippines, 13 p. C54

Prices in Filipino Pesos (7.3 pesos per US$1). Palay means husked rice. Pesticide containers in liters (l), grams (g) or kilograms (kg). The last column on the right is the percentage increase over the time period 1976-83.

page 5

a/ Yield difference between complete control and untreated check was zero or negativeb/ Yield difference between complete control and untreated check was less than the value of one application of 0.4 kg ai monocrotophos EC/hac/ Yield difference between complete control and untreated check was less than the value of one application of 1 kg ai carbofuran G/ha

Table 4. Comparison of the profitability of need-based (economic threshold) or calendar-based prophylactic insecticide treatment, Philippines, 1976-83.

Environment More profitable More profitable Crop culture than prophylactic than ET Province Cost (Pesos/ha) Application no. (no. crops) Cost (Pesos/ha) Application no. (no. crops)

Insect susceptible varietyRainfed dryland rice

Batangas (Tanauan) 57 0 2 254 1 0

Rainfed wetland rice

Cagayan (Tuegegarao) 50 0 2 546 1 0

Insect resistant variety

Rainfed wetland riceTransplanted single crop

Pangasinan (Manaoag) 277 1.3 1 772 2.3 2

Cagayan (Tuegegarao) 50 0 2 546 1 0

Second rice crop

Pangasinan (Manaoag) 333 1.1 1 451 1.3 4

Iloilo (Oton) 141 0.6 2 392 1.3 1

Direct-seeded first crop

Pangasinan (Manaoag) 145 0.5 2 207 1 2

Iloilo (Oton) 50 0 1 266 1 2

Cagayan (Tuegegarao) 96 1 1 193 1 1

Pre-germinated direct seeding (wet seeded rice)

Pangasinan (Manaoag) 332 1.4 3 560 1.4 0

Iloilo (Oton) 247 1.3 1 392 1.2 3

Irrigated transplanted riceWet season

Laguna (Calauan) 462 2 1 517 1 0

Nueva Ecija (Zaragoza) 406 1.7 2 477 1 0

South Cotabato (Marbel) 501 2.1 2 444 1.4 0

Dry season

Laguna (Calauan) 60 0 1 566 1 0

Nueva Ecija (Zaragoza) 437 1.4 0 497 5 2

Cagayan (Gadu) 164 0.5 1 591 1.3 0

Pangasinan (Manaoag) 52 0 1 437 1 0

Economic threhsold (ET) treatment Prophylactic treatment

page 8

Economic thresholds mentioned herein were in effect action thresholds.page 9

Insecticiede dosage (kg ai/ha). AI means active ingredient.