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Culturing of sweet sorghum is being considered as an excellent option for ethanol production, from an agronomical and industrial point of view. At present, information regarding the best soil water tension for beginning sweet sorghum irrigation is not available; hence, this study aimed to determine the adequate soil water tension under field conditions for beginning irrigation of four cultivars of sorghum. Two experiments were conducted at Nova Porteirinha, MG, in a randomized block design with sub-subdivided plots having four replications. Each experiment comprised six treatments of soil water tension (plots)-20, 40, 60, 80, 100, and 120 kPa-for resuming sweet sorghum irrigation, and four sweet sorghum cultivars (subplots)-BRS 508, BRS 509, BRS 511, and CMSXS647. After planting, the soil water level in the plots was elevated to field capacity (10 kPa), and then the treatments were applied. During treatment application, irrigation was resumed when the soil water tension reached the limit established in order to elevate the soil water tension to 10 kPa. The amount of water replaced during each irrigation was determined by generating a soil water retention curve for the experimental area. The following parameters were evaluated: green mass production, juice volume, soluble solids (Brix), and tons of Brix per hectare (TBH). The different soil water tensions and cultivars, agricultural year, and interaction between tension and year significantly affected (p ? 0.05) the characteristics evaluated, according to the F test. The agronomical characteristics of the evaluated cultivars showed linear relationship with water supply in the soil. According to TBH, irrigation of sweet sorghum needs to be performed when the soil tension reaches 20 kPa. The TBH values did not differ significantly among the four cultivars at the 5% significance level according to Tukey test.

This work was carried out in order to evaluate the intercropping of forage grasses with grain sorghumin two localities of Minas Gerais State. Two experiments were set in experimental areas of the Empresa de PesquisaAgropecuária de Minas Gerais (Epamig), in Leme do Prado and in Jaíba. The design was in randomized blockswith four replications. Grain yield, plant height and productivity of dry matter were affected by the cultivation site.Highest productivity of forage dry matter was observed in the sorghum Panicum maximum Jacq. intercropping, inthe two localities. Single sorghum presented greater grain yield in both localities. The intercropping of sorghum withBrachiaria decumbens and sorghum with Andropogon gayanus presented greater grain yield in Jaíba and Leme doPrado, respectively.

The objective of this study was to evaluate the productivity and quality of the juice of sweet sorghumcultivars at different row spacings and plant densities. Experiments were carried out in three localities of Minas GeraisState, Brazil. In each site the trial was conducted in a randomized complete block design, in a factorial 2 x 4 x 4 scheme,with four replications, comprising two genotypes (BRS 506 and BRS 507), four plant densities (100, 140, 180 and 220thousand plants ha-1), four row spacings (50, 70, 90 and 110 cm) and three locations in the State of Minas Gerais (NovaPorteirinha, Leme do Prado and Jaíba). Plant height, productivity of green matter, juice yield and Brix of the juicewere analyzed. The increase in population provided higher productivity of green matter and juice in the two cultivars.The location affected the green matter productivity, juice productivity and Brix of sweet sorghum, independent ofplant arrangement. Reduction of row spacing caused higher productivity of fresh mass and juice mass as a function oflocation.