LOCAL ADAPTABILITY TESTS OF PROMISING QUALITY RICE LINES UNDER CONDITIONS IN THE ILOCOS REGION

摘要

Testing for location-specificity; the Philippine Rice Research Institute Batac Station evaluated six (6) quality rice lines under Ilocos Region conditions. The different lines - PJ3-1; PJ3-5; PJ7; PJ17; PJ(T)4 and PJ(G)6 -- which are progenies from crosses between Japonica and Indica rices -- were evaluated in 2000-2001 under irrigated and rainfed conditions. Among the six lines; four lines (PJ3-1; PJ3-5; PJ7 & PJ17) matured early; 110-117 days after sowing (DAS); and these are suited in the rainfedareas of the Ilocos Region. PJ(T)4; a tungro-resistant line; matured at 134 to 139 DAS while PJ(G)6; a glutinous line; matured at 128-137 DAS. These two lines are suited for rainfed lowland conditions. In DS 2000 and 2001; PJ3-1; 3-5; PJ7 and PJ17 were shorter than PJ(T)4 and PJ(G)6. However; during the wet season; the lines were taller; 103 cm to 107 cm; under the rainfed and irrigated conditions. PJ(G)6 and PJ(T)4 grew as tall as 108-115 cm. Despite their height; the lines were all resistant to lodging. They produced productive tillers ranging from 13 to 19. The yields obtained during the dry season ranged from 4.2 to 6.8 t /ha. Except for PJ(G)6; higher yields of 6.0 to 7.1 t /ha were produced iji the rainfed areas during WS 2001; except for PJ(G)6.In terms of crop stand and eating quality; PJ3-5; PJ3-5; PJ7 and PJ 17 are preferred since they are comparable with the quality of IR64; the leading rice variety in the Philippines. Cost and return analysis shows that the PJ line realized higher yieldsand incomes than the inbred lines used in the different locations.