Herbigation in a cherry orchard - translocation and persistence of pendimethalin in the soil.

摘要

Application of herbicides with irrigation water (herbigation) has many advantages - uniformity, flexibility, avoidance of heavy machinery, cost efficiency etc. On the other hand, localized water and chemical applications are associated with a possibility of undesirable impacts on the crops and the environment. The subject of the present paper is the fate of the soil herbicide pendimethalin in the root zone and its effects on soil microbial activity. Three variants of herbicide application - microsprinkling, drip irrigation, and a back sprayer, as well as a non-treated control, were set in three replications in a sweet cherry orchard. In all treated variants, the herbicide was applied at a dose of 6.0 L/ha in 2.0 m wide row strips, after a water application rate of 5.0 mm. The investigation objectives were addressed from periodical soil sampling - 30, 60, 90 and 120 days after the treatment from the 0-5 cm and 5-10 cm layers for studying the herbicide migration and decomposition in the soil, and 7, 30, and 45 days after the application from the 0-10 cm and 10-20 cm layers for the soil microbial activity. Bioassay, with oat as a test plant, and standard microbiological methods, respectively, were used for analyzing the soil samples. The herbigation, especially by microsprinkling, increased herbicide efficiency - biological and economical - and did not have a negative effect on the fruit trees and the environment.