ABSTRACT: The study of adaptability and stability underlies the cultivar recommendation process for all crops. There is a considerable number of statistical methods available for this purpose, but little is known about their actual adoption by the Brazilian scientific community. The objective of this study was to carry out a systematic review of the scientific literature on the adaptability and stability methods used in maize and soybean in Brazil from scientific articles published between 1970 and 2017 in Brazilian journals. Article searches were carried out in journals indexed through the SciELO database. The articles were classified according to the year of publication and the adaptability and stability methods used. We also evaluated the pattern of association between methods. We found 113 articles on adaptability and stability in maize and soybean, in which 21 methods were listed. The most commonly used method was the Eberhart and Russell methodology. The Cruz, Torres, and Vencovsky along with the AMMI methods were also widely used. The number of articles using most methods decreased in the current decade, except for the GGE Biplot, MHPRVG, and Centroid methods. In studies with more than one method, the methods were more likely to be used together with the Eberhart and Russell methodology. Adaptability and stability in maize and soybean have been widely studied over the last several decades in Brazil, although the number of publications on this subject has decreased over this time period.

RESUMO A conservação dos órgãos da planta, como folhas e colmo, é essencial para que a cultura do milho atinja altas produtividades. O objetivo deste trabalho foi avaliar a influência da manutenção da área foliar, decorrente do uso de fungicidas, na integridade e composição do colmo e na produtividade do milho. O experimento foi conduzido em Uberlândia - MG, durante a segunda safra de 2016. O delineamento experimental foi o de blocos casualizados com seis repetições e seis tratamentos, sendo uma testemunha e os demais compostos por combinações de fungicidas pertencentes aos grupos químicos carboxamida, estrobilurina, triazol e ditiocarbamato. Avaliaram-se porcentagem de área verde foliar, densidade de colmo úmido e seco, força e altura de quebramento de colmo, teor de lignina e de celulose no colmo, produtividade de grãos e de matéria seca de colmo e quantidade de lignina e de celulose por hectare. Os tratamentos com fungicida proporcionaram maior área foliar e densidade de colmo, principalmente aqueles com carboxamida. Os fungicidas também aumentaram a força necessária ao quebramento de colmo e a altura de quebramento, porém não influenciaram o teor de lignina e de celulose no colmo. A produtividade de grãos e de matéria de seca de colmo e a quantidade de lignina e de celulose no colmo por hectare foram incrementadas pela aplicação de fungicidas, principalmente nos tratamentos com carboxamida. Aplicações de combinações de fungicida incluindo carboxamida proporcionam maior manutenção de área foliar, maior integridade de colmo, maior produtividade de grãos e maior formação de palhada.

ABSTRACT Conservation of vegetative organs, as leaves and stalks, is essential to achieve high maize production. The objective of this work was to evaluate the effects of leaf area maintenance due to fungicides spraying on stalk integrity, its chemical composition and grain yield. The experiment was conducted in Uberlândia - MG, during the second season of 2016. The experiment design was a randomized complete block with six replications and six treatments, representing combinations of fungicides belonging to carboxamide, strobilurin, triazole, and dithiocarbamate chemical groups, and the check treatment (without fungicides). The assessed traits were leaf green area, wet and dry stalk density, stalk breaking strength and height, stalk lignin and cellulose percentage, stalk dry matter, stalk lignin and cellulose content per hectare and grain yield. Treatments containing fungicides, especially the ones containing carboxamide, resulted in higher leaf green area and stalk density. Application of fungicides also increased stalk breaking strength and height; however, no effect was observed on stalk lignin and cellulose percentage. Grain yield, stalk dry matter production, and stalk lignin and cellulose contents per hectare were enhanced by fungicide application, with higher improvements in plants treated with carboxamide. Application of fungicides, mainly when combined with carboxamides, promotes higher maintenance of leaf green area, which leads to improved stalk integrity, higher grain yield, and higher straw production.

RESUMO Diversos estudos abordando a inoculação de cereais com micro-organismos diazotróficos são encontrados na literatura. Porém, em muitos experimentos os pesquisadores têm negligenciado a viabilidade da aplicação desses micro-organismos no sulco de semeadura, juntamente com as sementes, e o efeito da concentração das bactérias na fitoestimulação. Este trabalho teve como objetivo avaliar o efeito de doses de inoculante à base de Azospirillum brasilense aplicadas no sulco de semeadura do milho em combinação com diferentes doses de adubação nitrogenada. O experimento foi realizado em campo, em solo de cerrado. Adotou-se o delineamento estatístico de blocos ao acaso em esquema de faixas, composto por doses de nitrogênio (40; 100; 200 e 300 kg ha-1) e doses de inoculante líquido à base de A. brasilense aplicadas no sulco de semeadura (0; 100; 200; 300 e 400 mL ha-1). A dose de 200 mL ha-1 de Azospirillum se destacou na produção de grãos de milho. Este é o primeiro relato da aplicação eficiente de Azospirillum no sulco de semeadura do milho no cerrado brasileiro.

ABSTRACT Several studies addressing the inoculation of cereals with diazotrophic microorganisms can be found in the literature. However, in many experiments, investigators have overlooked the feasibility of applying these microorganisms to the furrow together with the seed, and the effect of bacterial concentration on phytostimulation. The aim of this work was to evaluate the effect of doses of an inoculant based on Azospirillum brasilense, applied to the seed furrow when planting maize, combined with different doses of nitrogen fertiliser. The experiment was carried out in the field, in soil of the cerrado region of Brazil. An experimental design of randomised blocks in bands was adopted, comprising nitrogen (40, 100, 200 and 300 kg ha-1) and doses of an A. brasilense-based liquid inoculant applied to the seed furrow (0, 100, 200, 300 and 400 mL ha-1). The dose of 200 mL ha-1Azospirillum was noteworthy for grain production. This is the first report of the effective application of Azospirillum in the seed furrow when planting maize in the cerrado region of Brazil.

O objetivo deste trabalho foi avaliar a influência da desfolha do milho no desenvolvimento e na produtividade de grãos. Seis ensaios foram conduzidos em diferentes safras e locais e em dois níveis de produtividade. Utilizou-se o delineamento de blocos ao acaso, com sete repetições. A desfolha foi realizada no estádio vegetativo V4 do milho (quatro folhas expandidas), e os tratamentos foram: remoção das duas folhas basais, remoção das quatro folhas expandidas, remoção total das folhas (secção da parte aérea) e testemunha (sem desfolha). Foram avaliados: duração do período vegetativo; e, em pré-colheita, altura de planta, altura de espiga, percentagem de plantas acamadas, força de quebramento de colmo, força de arranquio da planta e produtividade. A remoção das quatro folhas e a remoção total aumentaram a duração do período vegetativo e reduziram a altura de planta, a altura de espiga e a resistência do colmo ao quebramento. Esses níveis de desfolha também reduziram a produtividade, principalmente com a remoção total das folhas. A força de arranquio da planta não foi influenciada pela desfolha. A retirada de quatro folhas e do total das folhas reduz a produtividade de grãos, respectivamente, em 6,25 a 14,05% nos híbridos avaliados.

The objective of this work was to evaluate the influence of defoliation of maize on grain development and yield. Six trials were conducted in different growing seasons and locations and at two yield levels. A randomized complete block design was used, with seven replicates. Defoliation was made at the V4 vegetative stage of maize (four expanded leaves), and treatments consisted of: removal of the two basal leaves, removal of the four expanded leaves, total removal of leaves (aerial plant section), and a control (without defoliation). The following were evaluated: length of the vegetative period; and, at pre-harvest, plant height, ear insertion height, plant lodging percentage, stalk-breaking strength, force required to pull the plant, and yield. The removal of four leaves and the total removal of leaves increased the length of the vegetative period and reduced plant height, ear insertion height, and stalk strength against breaking. These defoliation levels also reduced yield, mainly with the total removal of leaves. The force required to pull the plant was not influenced by defoliation. Removal of four leaves and of all leaves reduces grain yield, respectively, in 6.25 to 14,05 in the evaluated hybrids.