Effect of gamma irradiated sodium alginate on red amaranth (Amaranthus cruentus L.) as growth promoter

In order to study the growth promotion behavior of sodium alginate (SA) on vegetable (red amaranth, Amaranthus cruentus L.), 3% aqueous solution of SA was irradiated by γ-radiation (Co-60) of various total doses (12.5–50.0 kGy) at a dose rate of 3.5 kGy/h. Viscosity of the irradiated SA was found to decrease with increase in the radiation dose. The average molecular weight was also decreased from 104 to 103 orders. Red amaranth was cultivated in 18 different individual plots and SA solution (150 ppm) was applied on red amaranth after 10 days of seedlings at every 6 days interval. The morphological characters of vegetables were studied randomly in different unit plots. The irradiated SA of 37.5 kGy at 150 ppm solution showed the best performance. Dry matter of red amaranth significantly increased at 37.5 kGy of irradiated alginate treatment which was about 50% higher than that of the untreated samples. The effect of SA on red amaranth was found significant increase; i.e. plant height (17.8%), root length (12.7%), number of leaf (5.4%) and maximum leaf area (2%) compared to that of the control vegetative plant production.