M. R. Amin

Productivity and economics of maize–squash intercropping at different planting systems

The competitive behaviors of maize–squash intercropping at different planting systems were studied at Regional Agricultural Research Station, Hathazari, Chittagong, Bangladesh during the Rabi season of 2016–17 to find out the suitable planting arrangement of maize–squash intercropping for maximum productivity and economic return. There were seven treatments i.e . T 1 = sole maize, T 2 = 1 row maize (100%) + 1 row squash (6 plants/row), T 3 = maize paired row (100%) + 1 row squash (5 plants/row), T 4 = maize paired row (100%) + 1 row squash (4 plants/row), T 5 = maize paired row (100%) + 2 row squash (5 plants/row), T 6 = maize paired row (100%) + 2 row squash (4 plants/row) and T 7 = sole squash. Results revealed that the Maize Equivalent Yield (MEY) was highest (18.39 t/ha) in T 5 treatment, where Maize paired row (100%) + 2 row squash (5 plants/row) was consummated. The highest Land Equivalent Ratio (LER) 1.62 was found in T 5 treatment . Benefit-Cost Ratio (BCR) was also the highest (3.29) in T 5 treatment. Maize paired row (100%) and two rows of squash (5 plants /row) was the suitable row arrangement of the intercrops for judicious use of land consisting optimum populations of the component crops to produce more yield and economic profit J. Bangladesh Agril. Univ. 16(1): 23-26, April 2018

Purification and properties of glutamate-phenylpyruvate aminotransferase from the ruminal protozoan Entodinium caudatum

Entodinium species are important in catabolic protein metabolism by the mixed ruminal microbial population. This study was conducted to purify, and investigate properties of one of the enzymes involved in amino acid metabolism by Entodinium caudatum, glutamate-phenylpyruvate aminotransferase (GPA; EC 2.6.1.64). GPA was purified 74-fold from a cell-free extract by ammonium sulfate precipitation and column chromatography with phenyl-superose, DEAE-Toyopearl 650M, Sephacryl S-100 HR, and Sephadex G-100. The molecular mass of GPA was estimated by SDS–PAGE to be 65.0 kDa. The optimum pH was 6.0 and it was found to be reactive over a wide range of pH from 5.0 to 10.5. Maximum activity of GPA occurred at 45°C and the activity declined at temperatures over 55°C. GPA was stable below 60°C. Aminooxyacetate and phenylhydrazine were highly inhibitory, and SDS, EDTA, and some heavy metal ions also inhibited activity. The purification and characterisation of the enzyme will help to isolate the gene and ultimately to understand the role of GPA in both anabolic and catabolic amino acid metabolism by Entodinium caudatum.