Bringing Medicinally Important Traditional Rice Accessions into Cultivation: dicinally Important Traditional Rice Accessions into Cultivation: Study on Agronomic Characters and Yield Potential

Abstract

Some traditional rice cultivars of Sri Lanka constitute natural medicines and used as popular remedies. However, presently these cultivars are not grown in the farmer fields in Sri Lanka due to less yield potential. Green revolution introduced a package of technologies with modern irrigation projects, pesticides, inorganic fertilizers and improved crop varieties. Those improved high yielding varieties out performed in the presence of adequate irrigation, pesticides, and fertilizers. In the absence of these inputs traditional varieties recorded significantly lower yields and they were gradually eliminated from the farmer field with time. In the present study some medicinally important traditional rice cultivars were grown in the field conditions and their agronomic characters and grain yield were evaluated. Rice cultivar Bg379/2 was used as a reference modern rice cultivar. None of the rice cultivars recorded a significantly equal yield and number of fertile tillers with those of the modern rice cultivar. Among tested rice cultivars Weda Heenati recorded 14.46 g/plant While all the other cultivars recorded less than 6.6 g/plant. However, due to less tillering ability of the traditional rice cultivars, many rice cultivars including Dik Wee accessions, Gonabaru, Rathel and Weda Heenati recorded higher harvest indices than that of modern rice cultivar Bg379/2. Filled grain percentage of Kuruluthudu 2 was significantly equal with the value of modern rice cultivar. The hundred grain weight of Kuruluthudu 2, Rathel and Weda Heenati were in between 1.3-1.5g (very small) while the highest value (3.2) was in Bg379/2. However, the economical yield per plant in all the traditional rice cultivars is significantly lower than that of modern reference variety. Present study categorizes medicinally important traditional rice cultivars according to age, tillering ability, fertility and plant height using IRRI standard evaluation system. Grain yield/plant and harvest index give the expected yield potential of each cultivar at the Held conditions.