Evaluation of Pine Kraft Lignins for Controlled Release of Alachlor and Metribuzin

Abstract
The controlled release of metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] and alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide] from pine kraft lignin was studied using14C-labeled herbicides and3H-labeled lignin with soil thin-layer chromatography. NB-5203-58 series and PC940 series kraft lignins adsorbed and desorbed metribuzin as soil plates were developed with water. PC671, a formulated kraft lignin control release product, did not provide controlled release with metribuzin. NB-5203-58B and PC940C were the most effective of their respective series of kraft lignins. PC940C also provided controlled release of alachlor.