Agronomic evaluation and farmers' acceptability of the System of Rice Intensification in Ilocos Norte, Philippines

To evaluate the performance of System of Rice Intensification and conventional rice production systems, a field experiment was conducted at PhilRice Batac Experiment Station during the wet season 2006. Thirty farmers in Ilocos Norte were interviewed for the documentation of the rice production practices, they also served as field evaluators of the experiment prior to harvest. The application of pure inorganic fertilizer and 50 percent inorganic and 50 percent organic fertilizer gave the best results in terms of agronomic parameters and grain yield compared with pure organic fertilization. Straw and root dry weight, root length, root pulling resistance, crop growth rate, total dry matter, leaf area, harvest index, and nitrogen and phosphorous uptake in grains did not differ significantly between pure inorganic fertilizer and 50 percent inorganic and 50 percent organic fertilizer but were generally higher than with pure organic fertilizer. The conventional method of planting 21-25 day old seedlings at 2-3 seedlings/hill, and with continuous irrigation gave more tillers, higher root pulling resistance, leaf area index, and harvest index and higher grain yield than SRI. Conventionally grown plants produced longer panicle, more filled grains, and higher 1000-seed weight than those under the SRI method. The reported yield levels of SRI were not obtained in the study because: 1) root damage on young seedlings when they were uprooted which affected tillering, 2) higher weed population due to intermittent wetting and drying irrigation, 3) low soil fertility in the experiment station, and 4) farmers' limited knowledge and skills on SRI techniques and practices. Grain yield under the two spacing did not differ significantly. Hence, for the variety used, 30- x 30 cm spacing may be recommended since it is more economical because of less seed requirement and less labor in transplanting. Farmer respondents believe that SRI practices are all important in maximizing yield. However, these are more labor intensive than their usual practices. The identified weaknesses of SRI in Ilocos Norte are: low soil fertility,high labor requirement, unavailability of good irrigation and high risk to environmental stresses (e.g. flooding and susceptibility to golden snails). Despite the constraints identified, most of the farmer evaluators mentioned their interest to try SRI in their rice fields. SRI has potential in Ilocos Norte but some modifications are needed to match Ilocos Norte conditions.