On-farm evaluation and selection of promising salt-tolerant lines and varieties conducted jointly by researchers and farmer-partners in Northwest Luzon have resulted in their faster adoption and diffusion in areas affected by salinity.

This was in a PhilRice paper that made it to the finals in a competition, extension category, during the recent annual scientific meeting of the Crop Science Society of the Philippines.

The authors of the paper are Presentacion C. Alquiza, Dr. Nenita V. Desamero, Dr. Reynaldo C. Castro, Democrito Rebong II, Lorainne A. Ildefonso, Anielyn C. Yadao, and Annie Espiritu.

Alquiza reported 29 elite lines that have not yet reached the national cooperative tests (NCT), six NCT-evaluated elite lines and six varieties were evaluated in salt-stressed rice fields in Paruddun Norte, Aparri, Cagayan in the first season. The number of lines tested in the next season was slightly altered.

Field days were conducted before the trials were harvested so that farmers can visually evaluate and select the best lines based on their own criteria. The farmers preferred lines that are tolerant to salinity, have more productive tillers, produce dense panicles, non-shattering, medium height, early maturing (90 -100 days) for the June to October crop, and medium maturing (110 -124 days) for the crop in November to April.

The most preferred lines were not necessarily the top yielders. For the wet season, the number one choice of Cagayan farmers was PR24847, which yielded only 4.91 tons per hectare. In like manner, farmers in Currimao, Ilocos Norte preferred IR55423-01 with a yield of 3.78 t/ha over 97WS/SAL-147, which yielded 5.02 t/ha. For the dry season, C62-5 with a yield of 4.78 t/ha was the top choice in Cagayan.

The line IR55423-01 was chosen because of its long straw, which Ilocano farmers use as mulching material for garlic production.

Amazingly, among the three salt-tolerant varieties included in the farm trials, only NSIC Rc106 was selected as one of the top 10 lines during the wet season and PSB Rc50 during the dry season in Cagayan. Not one of them passed the preference of Currimao farmers. This implies that despite having undergone long and rigorous tests, varieties not chosen by farmers do not have the traits they prefer.

As a result of the farm trials, the top 10 elite salt-tolerant lines were already planted in 30 hectares in wet season 2004, Alquiza said. And in the following dry season, 108 farmers in Claveria, Buguey, Aparri, Sta. Teresita and Camalaniugan, Cagayan already planted in 64 hectares. The area could have been bigger but a strong typhoon hit Cagayan and washed out the seedlings.

In like manner, the diffusion and adoption of the top five lines selected by Currimao farmers are increasing. At the bottom line, farm trials like this could reduce the cost of variety development as well as assure their adoption, the researchers concluded. - PhilRice