Resumo A pulverização de herbicidas sobre a rebrota do eucalipto é uma prática comum no setor florestal. Entretanto, observa-se a necessidade de várias operações em uma mesma área para controle das brotações. Objetivou-se avaliar a eficiência dos herbicidas glyphosate e imazapyr, aplicados no fuste principal antes do corte raso das árvores, no controle de brotações de eucalipto. Foram implantados sete tratamentos representados por doses de 3,0; 4,0 e 5,0 mL/fuste de glyphosate (Gli-Up® 360 g i.a L-1) e das doses de 0,3; 0,5 e 0,7 mL/fuste de imazapyr (Chopper Florestal® 250 g i.a. L-1), além de um tratamento-testemunha. A aplicação dos herbicidas foi realizada em inserções feitas nos fustes das árvores. Aos 30 dias após aplicação dos herbicidas, realizou-se o corte das árvores. Aos 150 dias após o corte das árvores, foram realizadas avaliações do número de brotações por cepa, número de cepas com presença de brotações, altura e a eficiência de controle das brotações. A aplicação de glyphosate promoveu redução do vigor das brotações. Porém, observou-se emissão de brotações em pelo menos 80% das cepas avaliadas. A aplicação da dose de 3 mL de glyphosate promoveu porcentagens de 80% de eficiência de controle. Contudo, observou-se que operações de controle adicionais seriam necessárias. A aplicação de imazapyr mostrou-se ineficiente com controle inferior a 25%. Portanto, conclui-se que a aplicação de glyphosate no fuste da árvore em pré-corte reduz o vigor de brotações de eucalipto. Adicionalmente, a aplicação de imazapyr, nas doses e forma de aplicação testadas, não é recomendada para controle de brotações de eucalipto.

Abstract Herbicide spraying on eucalyptus regrowth prior to planting reform is a common practice in the forest sector. However, several operations are needed in the same area for an effective sprout control. The objective of this work was to evaluate the efficiency of the herbicides glyphosate and imazapyr, applied to the main stem before the harvesting of the tree to eucalyptus sprouts control. There were set up 7 treatments, with application of doses of 3.0; 4.0; and 5.0 mL/stem of glyphosate (Gli-Up® 360g i.a L-1) and doses of 0.3; 0.5; and 0.7 mL/stem of imazapyr (Chopper Florestal® 250g i.a. L-1), in addition to a control treatment. The herbicide spraying consisted of the directed spraying of the herbicides on incisions carried out on the stem of the trees. The harvest of the trees was carried out 30 days after the herbicide spraying. Assessments about the number of sprouts per stump were carried out, the number of stump with presence of coppice, height and control efficiency of the coppice 150 days after harvesting. The glyphosate spraying promoted reduction of the sprout development and vigor. However, even with this reduction, it was observed presence of sprouts in at least 80% of the assessed stumps. The spraying of the dose of 3 mL of glyphosate promoted values next to 80% of control efficiency. Nevertheless, it was observed that new control operations would be necessary. The spraying of imazapyr was inefficient with control efficiency values less than 25%. In conclusion, the application of glyphosate to the main stem before the harvesting of the tree presents reduction in the eucalyptus sprout development. Additionally, the application of imazapyr, in the doses and form application tested, is not recommended to eucalyptus sprout control.

Resumo Ramas de batata-doce apresentam características satisfatórias para alimentação animal, porém não têm sido exploradas na forma de feno. Objetivou-se avaliar o uso de ramas de batata-doce para a produção de feno e a divergência genética em clones de batata-doce. Foram avaliados dez clones de batata-doce, conduzidos a campo em blocos ao acaso e cinco repetições. Foram determinados o teor de matéria seca, as produtividades de massa verde e massa seca (PMS), a relação folha e haste das ramas e a produção total e comercial de raízes (PRC). Obtidos os fenos, avaliaram-se as características MS, PB, FDN, FDA, lignina, amido, açúcares solúveis, macro e micronutrientes. Estimou-se a divergência genética entre os clones de batata-doce. O clone UFVJM-54 aliou alta PRC com maior PMS. Os fenos apresentaram teores de PB variando de 11,99 a 15,09%, FDN 47,22 a 55,55%, FDA 22,92 a 28%, e 6,87 a 13,72% de LIG. De forma geral, os teores de minerais nos fenos foram satisfatórios. Os clones foram separados em cinco grupos diferentes. As ramas de batata-doce podem ser utilizadas para a produção de feno. Os clones UFVJM-37, UFVJM-46 e UFVJM-54 são recomendados para cruzamentos com os demais genótipos.

Abstract Sweet potato branches have satisfactory characteristics for animal feed, but have not been exploited in the form of hay. The objective of this work was to evaluate the use of the sweet potato branches for the hay production and genetic divergence in sweet potato clones. Were evaluated ten sweet potato clones, conducted on the field in randomized blocks and 5 repetitions. Dry matter content, green mass and dry mass yield (DMY), leaf and stem ratio of branches and total and commercial root production (CRP) were determined. Gotten the hays, were evaluated the characteristics: DM, CP, NDF, ADF, lignin, starch, soluble sugars, macro and micronutrients. The genetic divergence among the sweet potato clones was estimated. The UFVJM-54 clone allied high CRP with bigger DMY. The hay presented content of CP ranging from 11.99% to 15.09%, NFD 47.22 to 55.55%, ADF 22.92 to 28%, and 6.87 to 13.72% of LIG. In a general way, the contents of minerals in hays were satisfactory. The clones were separated into 5 different groups. The sweet potato branches can be used for the hay production. The UFVJM-37, UFVJM-46 and UFVJM-54 clones are recommended for crossing with the other genotypes.

RESUMO As águas residuárias podem ser consideradas como uma fonte hídrica e nutricional excelente para as plantas cultivadas. Porém, a presença de altas concentrações de sais e de compostos tóxicos pode afetar negativamente as plantações. Avaliou-se o efeito da irrigação com diferentes concentrações de água residuária tratada sobre o acumulo de nutrientes e os aspectos fisiológicos do milheto (Pennisetum glaucum (L.) R. Br.) cultivado em solo argiloso e franco arenoso. O estudo foi conduzido em casa de vegetação (16°40’57,50” S; 43°50’26,07” O; 650 m) em esquema fatorial 5 x 2, consistindo de cinco níveis de concentração da água residuária tratada (0, 25, 50, 75 e 100%), combinado com dois tipos de solo (argiloso e franco arenoso). O delineamento estatístico do experimento foi em blocos casualizados com quatro repetições. O aumento na concentração de água residuária tratada na água de irrigação aplicada em solo argiloso e franco arenoso favoreceu o aumento da fotossíntese líquida, taxa de transpiração, condutância estomática, teor de clorofila foliar e acumulo de macro e micronutrientes nas plantas de milheto. Plantas de milheto cultivadas em solo argiloso apresentam aumento médio de 23% na capacidade de troca de gases e de 71% no acumulo de macro e micronutrientes, quando comparado com os tratamentos em solo franco arenoso. Portanto, a água residuária tratada contribui para o aumento da capacidade de troca de gases e maior acumulo de nutrientes em plantas de milheto, o que representa uma alternativa para a redução da demanda por água doce e uso de fertilizantes químicos.

ABSTRACT Wastewater can be considered an excellent nutritional and water source for cultivated plants. However, the presence of high concentrations of salts and toxic compounds can negatively affect crops. The effect of irrigation with different concentrations of treated wastewater on the accumulation of nutrients and gas exchange aspects of millet (Pennisetum glaucum (L.) R. Br.) grown in clay soil and sandy loam soil was analyzed. This study was conducted in a greenhouse (16°40’57,50” S; 43°50’26,07” O; 650 m) in a 5 x 2 factorial design, consisting of five levels of concentration of treated wastewater (0, 25, 50, 75, and 100%), combined with two types of soil (clay and sandy loam). The experiment was designed in randomized blocks with four replicates. The increase in treated wastewater concentration in irrigation water applied to clay soil and sandy loam soil favored the increase of net photosynthesis, transpiration rate, stomatal conductance, leaf chlorophyll content and accumulation of macro- and micronutrients in millet plants. Millet plants grown in clay soil showed an average increase of 23% in gas exchange capacity and 71% in accumulation of macro- and micronutrients, when compared with treatments in sandy loam soil. Therefore, treated wastewater contributes to the increase in gas exchange capacity and greater accumulation of nutrients in millet plants, which represents an alternative for reduced demand for fresh water and use of chemical fertilizers.

ABSTRACT. The aim of this study was to obtain information for the genetic improvement of kale through repeatability and phenotypic stabilization studies and to compare methodologies that represent the reliability of the estimated parameters. Thirty-three half-sib progenies were evaluated in a randomized block design with three replicates and six plants per plot. Eight harvests were evaluated in terms of the yield of fresh leaves, number of shoots, number of leaves and average mass of leaves. Then, a phenotypic repeatability and stabilization study was performed, estimating the genetic parameters σ2a, σ²g, σ²e, and the coefficient of environmental variation and repeatability using the frequentist and Bayesian methodologies. To evaluate the reliability of these estimates, intervals were obtained using the frequentist, Bayesian and bootstrap methods. It was verified that the reliable selection of progenies of half-sib of kale can be achieved in four harvests that were realized between 95 and 170 days after planting. It was observed that the frequentist and Bayesian methodologies are better suited to obtain reliable estimates of the genetic parameters evaluated, as the last one provided smaller amplitudes for the obtained intervals. The bootstrap methodologies are not recommended for phenotypic repeatability and stabilization studies in kale.