Breeding for the New Rice Variety “Tainan-Sen. 15” and its Characteristics
S. L. Chuang, G. C. Lin
Tainan-sen 15 is a new indica rice variety developed by Chiayi Branch Station of Tainan District Agricultural Improvement Station. The female parent of this variety is Nan-Sen 2, which has cold tolerance and high-yielding abilities. The male parent, IR 22, which was obtained from IRRI is a disease resistant line. These parental lines were held the crosses in the first crop season in 1971 and this new rice variety was selected out in the second crop season 1973. Then it passed through 3 different classes of comparative yield trials and local as well as regional yield trials in the whole island. Meanwhile it also was subjected to the cold tolerance, disease resistant, and rice quality tests. The results showed that it was a quite prominent rice variety. In May 1980, this new variety had been authorized by the New Crop Variety Scrutiny Committee held by the Department of Agricultural and Forestry for registration and release to farmers. This new rice variety possesses the good characteristics from its parents, such as: cold tolerance, anti-lodging, disease resistance and good rice quality, etc. Its grain color is yellow with black purple apicule rarely and awnless. Its plants were half-dwarf, 84.6 cm high in the first crop season, 96.9 cm high in the second crop season. Its stalk is tough and not easily lodged. Since it has good tillering ability, so it could produce numerous panicles, 20.7 panicles in the first crop season, 16.8 panicles in the second crop season. It takes 119 days for this new rice variety to ripen in the first crop season, 103 days in the second crop season. The yield in the high class test was 7095 kg/ha in the first crop season with 18.9% increase over the ck variety Chianung-sen, 11,5228 kg/ha in the second crop season the same as those of ck variety. In the local yield trial it produce 7313 kg/ha in the first crop season with 9.0% increase over the Taichung native 1. 5501kg/ha in the second crop season having 12.5% better than those of Taichung native 1. The yield trial in the direct seeding was 6084 kg/ha with 7.1% increase over the ck variety Chianung-sen 11 in the first crop season, 5574 kg/ha in the second crop season having 17.3% better than those of Chianung-sen 11. In the disease and pest resistant test the results had been summarized as follows: 1. It is resistant or intermediate resistant to the rice blast disease. 2. It is resistant or intermediate resistant to the bacterial leaf blight. 3. It is susceptible to the sheath blight of rice. 4. It is susceptible to the brown planthoppers.
This new rice variety showed intermediate tolerance to coldness and fertilizer but had the excellent rice quality. The milled rice percentage was high, reached 79.3% in both crop seasons. The amylose content in the grains was high.
To sum up it is a middle long grain indica rice variety with high-yielding, anti-lodging abilities and good rice quality. It also showed resistance to coldness, the bacterial leaf blight and the rice panicle blast disease, which were easily to infect the long grain indica rice varieties. Through various yield trials the results revealed that this variety could be adopted for cultivation in the first and second crop seasons in the whole island and the intermediate crop season in Chianan area and proved that it is a good variety for direct seeding else.