Oscar Mitsuo-Yamashita’s research while affiliated with State University of Mato Grosso and other places

Destruction of the harvest of cotton stalks should be done after it. However, destruction by ploughing prevents continuing with direct sowing, which makes chemical management an ally in soil conservation. The objective was to identify the most effective dose of 2,4-D, associated with different herbicides and the timing of administration for the control of transgenic cotton shoots for tolerance to glyphosate and glufosinate. The treatments consisted of the use of the herbicide 2,4-D, alone at doses of 670 and 1 340 g ha-1, and associated with the herbicides carfentrazone, flumiclorac, chlorimuron, flumioxazin and imazethapyr at three application times: 0 days after mechanical mowing (0 DAMM), 25 DAMM, and 0 DAMM + 25 DAMM. Regrowth evaluations were performed at 15, 30, and 45 days after the first and second applications, determining the dry biomass of the shoots. In terms of herbicide use time, the best results are obtained when they applied at 0 DAMM + 25 DAMM. Higher doses of 2,4-D (1 324 g ha-1) make it more efficient; in relation to herbicides, variations were perceived in their behavior depending on the time of evaluation, the application, and the dose of 2,4-D used. During the last measurement period, 45 days after application, 2,4-D+carfentrazone and 2,4-D+flumiclorac had the lowest dry shoot masses. The experiment was conducted in 2014. It was concluded that there is a lower rate of cotton regrowth when the application of the herbicides is repeated at 0 DAMM and 25 DAMM. The 1 324 g ha-1 dose of 2,4-D is more efficient. 2,4-D+carfentrazone and 2,4-D+flumiclorac promoted lower dry mass 45 days after administration of the treatments.

The aim of the present study was to investigate the use of homeopathic preparations to reduce the harmful effects caused by auxin herbicide residues on seed germination and early development of cucumber seedlings. The statistical design was completely randomized (DIC) in a 3x5+2 factorial scheme, with four replications. The treatments were the combination of three homeopathic preparations (Nux vomica, Carbo vegetabilis and Arsenicum album), in five centesimal dynamizations (6CH; 12CH; 18CH; 24CH and 30CH), plus two controls (T0= distilled water and TH = herbicide (Artys™) without homeopathic treatment). Each experimental unit consisted of transparent acrylic boxes (Gerbox™) with 25 cucumber seeds, distributed over two sheets of paper for germination and moistened with homeopathic treatments. The experimental units were kept in a BOD germination chamber (in a controlled environment at 25 ºC and 12 ho of light). On the tenth day after the installation of the experiment, the following variables were evaluated: percentage of germination, shoot length, root length, phytointoxication, percentage of dead seedlings and total dry mass. The homeopathic treatment of cucumber seeds contaminated with picloram + 2,4-D herbicide (Artys™) causes positive changes, causing interesting effects on seed germination, but it is not efficient for the total neutralization of the effect caused by the herbicide 2 picloram + 2,4-D and development of early cucumber seedlings. However, for some variables, the results are inconclusive with the preparations (Nux vomica, Carbo vegetabilis and Arsenicum album), and their ultradilutions (6CH, 12CH, 18CH, 24CH and 30CH), requiring more research to evaluate and describe the complexity of properties inherent to homeopathic treatment.