Contribution of breeding to increasing soybean grain yield and grain quality

The objective of this research was to determine the genetic gain in grain yield and grain quality accomplished by recently developed domestic soybean elite lines and to determine ways to improve these traits further. Realized gains were estimated by comparing recently developed most promising domestic soybean lines of maturity groups (MGs) 00, 0 and I with commercial cultivars (standards) in comparative field tests during three consecutive years (2002–2004) in Osijek, Croatia. Mean values, broad-sense heritability, genetic gain and relative genetic gain from selection were calculated for grain yield, protein and oil content in grain. The obtained results of biometrical analysis showed genetic improvement in productivity and quality of new domestic soybean elite lines within MGs 00, 0 and 1. The high agronomic performances of this breeding material will considerably contribute to the increasing and improving soybean production in our region as well as genetic improvement of domestic soybean cultivars further

Response of maize and soybeans to ameliorative fertilization in Bjelovar-Bilogora county

Maize and soybeans were grown under field conditions on acid soil (pH in KCl = 3.99). The field trail was conducted in spring 2004 as follows: a = ordinary fertilization, b = a + NPK-1, c = a + NPK-2, d = a + NPK-3 and e = a + NPK-4. The fertilizer NPK 10:30:20 was source of P and K (using in amounts 416, 1249, 2082, 2916 and 3748 kg/ha, for the treatments a, b, c, d and e, respectively. Nitrogen amount was equilized for all treatments by addition of adequate quatities of CAN (calcium ammonium nitrate: 27% N) were used. The experiment was conducted in four replicates. By application of the ameliorative rates of NPK fertilizer, grain yields of maize significantly increased to level of 14% compared to standard fertilization (12.33 and 14.00 t ha −1 , for the control and the second rate of NPK fertilization, respectively. Only the highest rate of NPK fertilizer resulted by significant increase of protein in grain. Residual response of soybean (the growing season 2005) to the fertilization was considerably higher compared to maize, because yields of soybeans were increased up to 32%. Protein contents in soybean grain were independent on the fertilization, while oil contents were increased up to 0.66% compared to the control

Response of soybean to foliar fertilization with magnesium sulfate (epsom salt)

Six cultivars of soybean ( Glycine max (L.) Merr.) maturity groups 0 and 1 were evaluated in relation to the response to foliar fertilization with two levels of Epsom salt (ESFF) on grain yield, protein and oil content in grain. A field study conducted in Eastern Croatia during four years (1998–2001). The obtained results showed significant increasing of grain yield, protein and oil content in grain affected by ESFF. At investigated traits were non significant differences between two treatment levels. Interaction ESFF with cultivars as well as with years was significant, respectively