Germinação de sementes de soja RR sob efeito do Glifosato

Abstract

This study aimed to verify if the use of glyphosate affects in the early development of soybean in the laboratory and, identify the abnormalities in the standard germination test, caused by the herbicide in Roundup Ready soybean cultivars. We used soybean seeds from the cultivars M8644IPRO M8349IPRO, M8210IPRO, BRS8280RR, M9056RR, and TMG1288RR. Seeds were treated with dosages of herbicide of 0, 10, 53, 74, 90, 100, 127, 159, 190, and 200 mg L-1. Standard germination test was carried out using the methodology established by R.A.S. After germination period soybean seedlings were evaluated taking as evaluation variables, normal seedlings, abnormal seedlings and dead seeds given in percentages. Characterization of the symptoms caused by the herbicide was performed by visualization of seedlings with symptoms and description of the morphological evidence. Statistical analysis was performed by the Winstat program, means were submitted to Tukey test at 5% of probability and, linear regression. According to the increasing doses, all cultivars tested showed more susceptibility to the appearance of abnormalities. BRS8280RR is the most susceptible cultivar tested. Doses of the herbicide higher than 53 mg L-1 i.e. equivalent to 7 liters per hectare cause phytotoxicity observed by abnormalities or invalidating the germination of seedlings.