Effect of presowing treatment of seeds with insecticides on nodulating ability, nitrate reductase activity and plastid pigments content of lucerne (Medicago sativa L.)
Institute of Forage Crops, Gen. Vl. Vazov Str. 89, Pleven 5800, Bulgaria;e-mail: viliana.vasileva@gmail.com
Abstract:
To determine the effect of presowing treatment of seeds on the nodulation ability, nitrate reductase activity and plastid pigments content of lucerne (cv. Obnova), a pot trial was carried out at the Institute of Forage Crops – Pleven, Bulgaria. The insecticides Promet 400 SK (furathiocarb) at the dose of 3 L, and Carbodan 35 ST (carbofuran) at the dose of 1, 2 and 3 L 100 kg-1 seeds were used. It was found that the insecticides tested did not depress the nodulation. Nodule number and specific nodulation ability when treated with Carbodan 35 ST at the dose of 3 L 100 kg-1 seeds exceeded that of the control by 23% and 7%, respectively. The root length for the variants with presowing treatment of seeds was higher as compared to the control by 7 to 26%. The variant with Carbodan at the doses of 2 and 3 L 100 kg-1 seeds and Promet increased nitrate reductase activity in roots, and that with Carbodan at the dose of 1 L 100 kg-1 seeds- in the leaves. Total content of plastid pigments increased in all variants with Carbodan and was lower than the untreated control in the variant with Promet.
Key words:
lucerne, nitrate reductase activity, nodulation, plastid pigments, root mass