Agronomic characteristics of elite soybean lines and the response to pod shattering

Abstract The soybean productivity can be increased simultaneously by improving the genetic potential and saving the yield losses due to pod shattering. The research aimed to evaluate the agronomic characters and seed yield of 14 soybean elite lines and two check varieties, and to identify their resistance to pod shattering. The experiment was conducted in two stages, i.e. field, and laboratory research. The field experiment was conducted in Mojokerto (East Java, Indonesia) from February to May 2019, and arranged in a randomized block design using 16 soybean genotypes with four replications. The pod shattering resistance was evaluated using the oven-dry method in the laboratory of ILETRI, Malang. The agronomic characters of days to flowering, days to maturity, 100 seed weight, and seed yield were significantly different among genotypes, meanwhile, the other agronomic characters (plant height, number of nodes, number of branches, number of empty pods, number of filled pods, seed weight per plant) were not significantly different. The range of seed yield of 14 elite lines was 2.76 – 3.14 t/ha, and the check varieties of Anjasmoro and Gema were 2.56 t/ha and 2.76 t/ha, respectively. All elite lines have a large seed size but medium maturity. The shattering evaluation obtained two resistant lines and twelve elite lines as very susceptible to pod shattering. Combination of the characters of high yield (based on the LSI value) and shattering resistance resulted in two elite lines with high yield and shatter-resistant, and eleven high yielding lines but susceptible to pod shattering. Those elite lines could be recommended for varietal development, but with the implication that the high yielded lines and susceptible to shattering need to be harvested immediately after maturity, thus were suggested to be developed in areas with no labor scarcity. On the contrary, it was possible to delay harvest for the resistant elite lines without causing significant yield losses.