AGRONOMIC EVALUATION OF PROMISING FCV TOBACCO VARIETIES IN KARNATAKA LIGHT SOILS
Abstract
Field experiments were conducted to evolve suitable agronomic packages for promising pre-release wilt resistant FCV tobacco lines FCH 221 and FCH 222 during 2009 and 2010 crop seasons on red sandy loam soils of Karnataka Light Soils (KLS). The treatments consisted of 2 levels of spacing and 2 levels of topping in main treatments and 3 levels of nitrogen in sub-plots in a splitplot design with three replications. The results revealed that 100 x 55 cm spacing (18,181 plants/ha) was better than 100 x 60 cm spacing (16,666 plants/ha). Adopting 22 leaves topping increased cured leaf and top grade equivalent yield by 4.6 and 5.4%, respectively as compared to lower topping at 20 leaves in line FCH 221. The N application at 60 kg/ha was found optimum for maximizing both the cured leaf and top grade equivalent compared to 50 or 70 kg N/ha. Similarly the recommended spacing of 100 x 55 cm with 18,181 plants/ha was ideal for the line FCH 222. Even though there was no significant differences between the two levels of topping, 20 leaves topping was found advantageous as there was improvement in productivity (up to 8.1%) over 22 leaves topping, especially during the dry season. The application of N at 60 kg/ha was found to be optimum dose as the application of N beyond 60 kg/ha did not significantly increase the yield of cured leaf or top grade equivalent. The cured leaf quality parameters like nicotine, reducing sugars and chlorides were not affected by various cultural practices adopted in both the lines. Hence, adopting 100 x 55 cm spacing and 22 leaves topping with application of 60 kg N/ha (in 2 splits) for line FCH 221 and 100 x 55 cm spacing and topping at 20 leaves with N application of 60 kg/ha (in 2 splits) in line FCH 222 would be the ideal agronomic practices for maximizing both the cured leaf and top grade equivalent yield with desired quality parameters in these lines under KLS conditions