Investigation of Tank-Mixed and Reduced Rate of Imazethapyr, Bentazon and Sethoxydim on Soybean Antioxidant Enzymes Activity

Soybean antioxidant enzymes activity can change within different herbicide and herbicide active ingredient rates application but it is not corroborating to all herbicides and doses, hence more survey will help to identify herbicide effect on soybean antioxidant enzymes. Goals was to estimate five antioxidant soybean enzyme activities during herbicide tank-mix under different reduced rate exposure. Completely randomized factorial design with 3 replications was used to survey data variance and simple mean comparison used to compare treatment effect on enzymes activity. Herbicide treatment were apply at soybean v2 growth stage by backpack sprayer with v type nuzzle. There were two main treatment consist of herbicide treatment in 7 level composed of single exert of Imazethapyr, Bentazon and sethoxydim, doubled solution of Imazethapyr + Bentazon, Imazethapyr + sethoxydim and Bentazon + Sethoxydim and tripled solution, consist of Imazethapyr + Bentazon + sethoxydim active ingredients. Second treatment was herbicide different rates in 3 levels, where it was compose of: full herbicide dose (equals to 100% of producer recommended dose), reduced to 60% of recommended active ingredient per acre and reduced to 30% of recommended active ingredient per acre. Minimum SOD activity registered at imazethapyr + bentazon + sethoxydim which it was 1.9 iu that induced at reduced rate of 10, 96 and 37 gr a.i ha-1 respectively. In contrast ascorbate peroxidase increased dramatically at bentazon treatment over 960 gr a.i ha-1, which it raises from 1.2 i.u in control to 7.2. Lowest APX activity demonstrated at imazethapyr + bentazon + sethoxydim which used as reduced rate of 30% of full recommended dose of each solution that it fit to 10, 96 and 37 gr a.i ha-1 respectively. Maximum APX activity that registered 7.2 i.u recorded at bentazon in full rate of 960 gr a.i ha-1. Sethoxydim at full rate of 375 gr a.i ha-1 induced maximum CAT activity, where registered 5.2 i.u, which in compare of control treatment in raised 10 times. Accordance to other enzymes, minimum CAT activity obtained at reduced to 30% of label recommended of imazethapyr + bentazon + sethoxydim treatment. Throughout all treatment by reducing herbicide rates enzymes activity diminished, similarly tank-mixed herbicide lower enzymes activity which it led to promote using reduced herbicide rate on soybean.