ABSTRACT Selection and dosage of desiccating herbicides may bring benefits to bean harvesting and its seed quality. This study aimed to assess yield, apparent specific mass and coloration of azuki bean seeds after pre-harvesting desiccation with different herbicides and doses and subsequent storing. In a first trial, we tested paraquat 400 (g ai ha-1), ammonium glufosinate (400 g ai ha-1), glyphosate (720 g ai ha-1), flumioxazin (30 g ai ha-1) and control. In second and third trials, we tested various doses of saflufenacil (0, 50, 75, 100, 150 and 200 g ai ha-1) and flumioxazin (0, 20, 25, 30, 35 and 40 g ai ha-1). All treatments were divided into plots and the dates of evaluation (at harvest and six months after harvest) into subplots with four replications. Even after storage, paraquat, ammonium glufosinate, glyphosate and flumioxazin had no effect on yield, specific mass or even coloration of azuki bean seeds. None of the doses of saflufenacil and flumioxazin impaired yield, specific mass and L* value of seeds, which is associated to lightness. Nevertheless, after six-month storage, the seeds desiccated with saflufenacil and flumioxazin lost color intensity and purity as function of the dose.

RESUMO Objetivou-se, nesta pesquisa, avaliar o efeito do uso do herbicida saflufenacil como dessecante em pré-colheita e do armazenamento sobre a qualidade fisiológica e sanitária de sementes de feijão-azuki. Foram testadas seis doses do herbicida saflufenacil (0, 50, 75, 100, 150 e 200 g a.i. ha-1) e duas épocas de avaliação da qualidade das sementes: colheita e seis meses após a colheita. A aplicação do dessecante ocorreu na maturidade fisiológica do feijoeiro azuki e as sementes colhidas foram armazenadas em sacos de papel (Kraft) em ambiente natural, a 25,4 ± 3 ºC de temperatura e 67,3 ± 3% umidade relativa. O saflufenacil pode ser utilizado até a dose de 65 g a.i. ha-1 sem prejudicar a qualidade fisiológica das sementes. O armazenamento provocou queda na percentagem de germinação, aumento no número de plântulas anormais e redução no tamanho e da massa seca das plântulas. A dessecação em pré-colheita e o armazenamento reduzem a infestação Cladosporium, Fusarium, e Rizhopus nas sementes de feijão-azuki.

ABSTRACT The objective of this study was to evaluate the effect of using the herbicide saflufenacil desiccant pre-harvest and storage on the physiological and sanitary quality of azuki bean seeds. Six doses of saflufenacil herbicide (0, 50, 75, 100, 150 and 200 g a.i. ha-1) were tested and two evaluation periods of seed quality: harvest and six months after harvest. The desiccant application occurred at physiological maturity of azuki bean and seeds were stored in paper bags (kraft) under natural conditions - 25.4 ± 3 °C temperature and 67.3 ± 3% relative humidity. The saflufenacil may be used up to a dose of 65 g a.i. ha-1, without harming the physiological seed quality. The storage caused a drop in the percentage of germination, increase in the number of abnormal seedlings and reduction in size and dry mass of seedlings. Desiccation pre-harvest and storage reduces the infestation of Cladosporium, Fusarium and Rizhopus on the azuki bean seed.