The possibility of increasing soybeann mutant lines production

Four promising mutant lines from induced mutation of soybean variety ORBA : 68/PsJ, 69/PsJ, 227/Bd, and 104/Bd, were planted with 6 different plant densities at Citayam experimental station. The plant densities were: 10 x 20 cm; 15 x 20 cm; 20 x 20 cm; 10 x 40 cm; 15 x 40 cm; 20 x 40 cm. This experiment was carried out during the dry season 1985 using a factorial design in 4 replications and with plot size of 1 x 2 m2. The results showed that yield per plant decreased as the plan density increased, but the yield per plot of ORBA or its mutant lines on a certain plant density might increase up to 100% as compared to the control plot with 20 x 40 cm plant density. Mean while, another experiment with a similar design was carried out to see the posible increase of mutant lines productions when use in a multiple cropping system. For this purpose, the plants were planted under a shelter (+50% reduction of light intensity). There were 6 shelter treatments : without shelter, sheltered at the planting time sheltered 7 days after planting (DAP), 21 DAP, 35 DAP, and 49 DAP. Although the yield per plant reduced in line with duration of sheltering, sacrificing yield for certain duration of sheltering of a definite mutant line was not significantly difference. (author). 3 refs.; 4 figs.; 7 tabs