Thermal Requirement, Heat and Radiation Use Efficiency of Kharif Soybean in Middle Gujarat Region as Influenced by Cultivars and Plant Geometry
Vibha Tak *
Agricultural Meteorological Cell, N. M. College of Agriculture, Navsari Agricultural University, Navsari- 396 450 (Gujarat), India.
M. M. Lunagaria
Department of Agricultural Meteorological, B. A. College of Agriculture, Anand Agricultural University, Anand- 388 110 (Gujarat), India.
V. B. Virani
Agricultural Meteorological Cell, N. M. College of Agriculture, Navsari Agricultural University, Navsari- 396 450 (Gujarat), India.
P. K. Parmar
Agricultural Meteorological Cell, N. M. College of Agriculture, Navsari Agricultural University, Navsari- 396 450 (Gujarat), India.
*Author to whom correspondence should be addressed.
Abstract
The present study proposes to measure the thermal requirements, heat and radiation use efficiency of kharif soybean cultivars (NRC 37, GS 1 and GS 2) in the central region of Gujarat. The findings of study conclude that among all the different geometry 30 x 10 cm produced highest seed (4403 kg/ha) and total biomass yield (5818 kg/ha) over the other two spacing because higher heat use efficiency (heat use efficiency (HUE) for Growing degree day (GDD)- 0.69 kg/ha/°C Day; HUE for Heliothermal units (HTU) - 0.14 kg/ha/°C Day hour; HUE for Photothermal units (PTU) - 0.05 kg/ha/°C Day hour). The cultivar NRC 37 (4415 kg/ha) produced highest seed yield followed by GS 1 (3799 kg/ha) and GS 2 (3670 kg/ha). Heat unit requirement of cultivar NRC 37 (GDD - 1952°C Day; HTU – 9894°C Day hour; PTU-25974°C day hour) was more as compared to GS 2 (GDD - 1951°C day; HTU – 9893°C day hour; PTU-25973°C day hour) and GS 1 (GDD - 1931°C day; HTU – 9809°C day hour; PTU-25681°C day hour), respectively. The radiation use efficiency (RUE) for seed yield and biomass are more in 45 x 5 cm geometry.
Keywords: Soybean, GDD, HTU, PTU, HUE and RUE