FARSHID ALIPOUR-ABOOKHEILI1, HAMID-REZA MOBASSER2, MORTEZA SIAVOSHI3* AND FARSHID GOLMAEI2
1 Department of Agronomy, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 Department of Agronomy, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran.
3 Department of Agricultural Science, Payame Noor University, I.R. of Iran.
In order to investigate the effects of plant density and planting season on phonological traits, yield and yield components of Soybean (Line 033) were carried out at Research Farm of Islamic Azad University, Qaemshahr Branch, in two consecutive years 2016 and 2017. This experiment was conducted as split plot in randomized complete block design with three replications. The planting season was in three levels: spring (May 17), summer (July 6) and summer delay (August 6) as main factor and sub factor including four plant densities (20, 40, 60 and 80 plants per m2). The results showed that the plant height and the distance from the first pod to the surface of the ground for spring cultivation in the second year and for densities of 60 and 80 plants per m2 were higher than the first year, while the number of branches for the first year was more than the second year. Yield was increased (38.1%) with increasing plant density up to 80 plants per m2 while number of pods per plant and number of seeds per pod decreased. Maximum grain yield for the second year was obtained by spring planting and also in the same year with density 60 and 80 plants per m2 because of increase in number of pods, number of seeds per pod and 100 seed weight. In general, soybean (line 033) with low stem production capacity in Mazandaran province, Iran is recommended for spring planting and density of 60 plants per m2.
Keywords: Grain yield, Plant density, Planting season, Soybean and Year.