José Avelino Santos Rodrigues

Características químicas e digestibilidade in vitro de silagens de girassol

Silages of thirteen cultivars of sunflower (Helianthus annuus L.) were evaluated for chemical characteristics and in vitro dry matter digestibility (IVDMD). The silages were produced when the plants presented above 90% of ripe grains. The experimental procedure followed a entirely randomized design and the mean values were compared by SNK test (P<.05). The smallest content of dry matter, 19.8%, was obtained for the hybrid M737, and the highest were observed for Contiflor 7, with 31.2%, and Cargill 11, with 32.2%. The pH values varied from 4.1 up to 5.5, and the contents of ammonia-nitrogen as percentage of total nitrogen varied from 5.9% up to 14.6%. The general averages obtained for lactic, acetic and butyric acids were of 7.1%, 1.9% and 0.06%, respectively. The hybrid Rumbosol 91 presented the smallest percentage of crude protein, with 7.2%, while contents above 9.0% were observed for five cultivars. The general average of ether extract (EE), 14.7%, was quite high when compared to others contents usually obtained for roughage. The contents of neutral detergent fiber, acid detergent fiber (ADF) and lignin presented general averages of 45.8%, 35.7% and 6.4%, and were negatively correlated to IVDMD (general average of 49.8%). The silages presented low concentrations of residual soluble carbohydrates. The high contents of ADF and lignin, and the average of IVDMD (49.8%) can restrict the application of the silages of those cultivars of sunflower for more the exigent categories of animals, and the high medium content of EE can limit the level of inclusion of those silages in bovine rations.

Adaptabilidade e estabilidade em cultivares de sorgo

Information about cultivars behavior obtained from only one local and year may not be enough for a cultivar recommendation due to the genotype x environment interaction occurrence. Then, cultivars indication based on stability and repeatability is more consistent because it enables previewing theirs performance under many environments. This work studied the adaptability and repeatability of dry matter production of seven sorghum cultivars to be used as silage. Data came from two sites (Coronel Pacheco and Lavras, Minas Gerais) and were obtained during two years (1997/98 and 1998/99) using a casual block with three replications design. Cultivar AG 2002 was recommended because showed the best productivity, good performance preview and was the cultivar that approached more to the ideal standard. Also, Volumax cultivar may be recommended due to its good performance when growing in favorable environments.

Qualidade de silagens de híbridos de sorgo (Soghum bicolor (L.) Moench) de portes baixo, médio e alto com diferentes proporções de colmo+folhas/panícula: 1. Avaliação do processo fermentativo

The objective of this experiment was to evaluate the fermentative quality of sorghum silage of small, medium and high size with different stem+leafs/head proportions (100:00, 80:20, 60:40, 40:60, 20:80, 00:100), by means of lab analysis. The whole plant was used as control. The hybrids were cultivated and ensiled at 104 days of age in PVC lab silos measuring 10-cm of diameter by 40-cm of length (three replications per treatment). Silos were opened 56 days after the ensilage. The contents of dry matter (DM), soluble carbohydrates, ammonia nitrogen (N-NH3) and pH were determined. Differences were compared using SNK statistical test. Average silage pH value was 3.79 and NNH3/total nitrogen values were lower than 8% for all treatments. Silage’s DM values varied from 19.40 to 49.40%, but all treatments were well conserved considering pH and N-NH3. Silos densities were greater with the increase of head proportion. Original material soluble carbohydrate values were low for the majority of the treatments, but this did not prejudice the fermentation of the ensiled mass.The objective of this experiment was to evaluate the fermentative quality of sorghum silage of small, medium and high size with different stem+leafs/head proportions (100:00, 80:20, 60:40, 40:60, 20:80, 00:100), by means of lab analysis. The whole plant was used as control. The hybrids were cultivated and ensiled at 104 days of age in PVC lab silos measuring 10-cm of diameter by 40-cm of length (three replications per treatment). Silos were opened 56 days after the ensilage. The crude protein (CP) contents and the in vitro dry matter disappearance (IVDMD), total phenols, constituents of cell wall by sequential method. The differences were compared using SNK test for total phenols, being realized regression analysis for the other results. Original material soluble carbohydrates values were low for the majority of the treatments, but this did not prejudice the fermentation, because additional carbohydrates like hemicellulose and cellulose were used during ensilage, being the fall of these high in the heads and stem+leaves, respectively. Total phenol values increased with the ensilage, besides decrease in IVDMD did not occur, concomitantly. The heads addition to the plant reduced cell wall constituents and increased IVDMD values, indicating that, to produce good quality silage, a sorghum plant shall has, at least, 40% of heads and low lignin, tannins and cell wall constituents values.

Agronomic divergence of sorghum hybrids for silage yield in the semiarid region of Paraiba

The objective of this study was to evaluate the agronomic divergence of 25 sorghum hybrids (Sorghum bicolor L. Moench) in the semiarid region of Paraiba. A randomized block design with three replications was used for evaluation of plant height (PH), total natural matter production (TNMP) and total dry matter production (TDMP) and the percentage of components of DM (panicle, leaf blade, stem and dead matter) of the following hybrids: 866005, 866019, 866033, 866034, 866035, 866036, 866037, 866040, 866041, 866042, 866043, 866044, 870025, 870031, 870035, 870041, 870051, 870067, 870081, 870085, 870095, 1F305, BRS 610, Volumax, and XBS60329. Hybrid 1F305, followed by hybrid 866034, presented the highest average PH. There was a range from 7.679 to 20.948 kg/ha (average of 13,799 kg/ha) for TDMP. Hybrids 1F305, BRS 610 and Volumax presented less potential, and hybrids 866,041 and 866,042 were the most productive. Based on cluster analysis and subjective cut in 50% of dissimilarity, it was possible to establish four hierarchical groups, from which two stood out concerning productive characteristics. The group formed by hybrids Volumax, BRS 610, and XBS60329 presented lower averages for yield and lower percentage of panicle. Hybrids 866041 and 866042 show a higher total dry matter production, with values around 20,000 kg/ha.

Silage quality of sorghum hybrids (Sorghum bicolor (L) Moench) of small, medium and high size with different stem+leafs/head proportions: 2. Nutritional value evaluation

The objective of this experiment was to evaluate the fermentative quality of sorghum silage of small, medium and high size with different stem+leafs/head proportions (100:00, 80:20, 60:40, 40:60, 20:80, 00:100), by means of lab analysis. The whole plant was used as control. The hybrids were cultivated and ensiled at 104 days of age in PVC lab silos measuring 10-cm of diameter by 40-cm of length (three replications per treatment). Silos were opened 56 days after the ensilage. The crude protein (CP) contents and the in vitro dry matter disappearance (IVDMD), total phenols, constituents of cell wall by sequential method. The differences were compared using SNK test for total phenols, being realized regression analysis for the other results. Original material soluble carbohydrates values were low for the majority of the treatments, but this did not prejudice the fermentation, because additional carbohydrates like hemicellulose and cellulose were used during ensilage, being the fall of these high in the heads and stem+leaves, respectively. Total phenol values increased with the ensilage, besides decrease in IVDMD did not occur, concomitantly. The heads addition to the plant reduced cell wall constituents and increased IVDMD values, indicating that, to produce good quality silage, a sorghum plant shall has, at least, 40% of heads and low lignin, tannins and cell wall constituents values.

Germinação e crescimento inicial de variedades de sorgo forrageiro submetidas ao estresse salino

The purpose of this study was to evaluate the salt tolerance of six varieties of forage sorghum, based on germination percentage and seedling growth subjected to six salinity levels. The treatments were arranged in a completely randomized design, according to a factorial arrangement 6 x 6 with four replications containing 25 seeds. The treatments were six varieties (V) of forage sorghum [F305 (V1), BRS 655 (V2), BRS 610 (V3), Volumax (V4), 1.015.045 (V5), 1.016.005 (V6)] and six salinity levels [0 (distilled water), 2.5, 5.0, 7.5, 10.0 and 12.5 dS m-1]. Experiment was conducted at the Laboratory of Seed Analysis of Embrapa Semiarido in August 2012. The variables assessed were percentage of germination, shoot (PA) and root (R) length, ratio PA/R, shoot and root fresh mass, shoot and root dry mass. Salinity levels did not affect the seed germination of varieties of forage sorghum until the conductivity of 10 dS m-1. The salinity levels between 3 and 5 dS m-1 favored the growth of shoots and roots, showing good tolerance to salinity of forage sorghum varieties, especially F305, Volumax and 1.015.045.

Espaçamento e densidade de semeadura para cultivares de sorgo granífero no semiárido

There is little information about sorghum management in semiarid areas. Therefore, three row spacing and three sowing den- sities of sorghum grain cultivars were evaluated during two crop seasons, in the North of Minas Gerais State, Brazil. In each season, two experiments were carried out on contiguous areas, adopting 50 cm, 70 cm and 90 cm as row spacing in the first one and three sowing densities (100000, 140000, 180000 plants ha -1 ) in the second one. In both experiments, four cultivars were evaluated: SHS400, 1G220, BRS310 and 0992045. The experimental design was in random blocks, in 3 x 4 factorial schemes, with three repetitions. Reduction in row spacing promotes increases in grain and panicles productivity of grain sor- ghum. The viability of increasing sowing density depends on cultivar and row spacing and of climatic conditions prevailing in cropping year. The BRS310 and 1G220 cultivars are promising for grain production in the North of Minas Gerais State.

Resistance of Commercial Hybrids and Lines of Sorghum, Sorghum bicolor (L.) Moench., to Diatraea saccharalis (Fabr.) (Lepidoptera: Pyralidae)

Commercial sorghum hybrids and Embrapas lines were evaluated regarding resistance to sugarcane borer. Two field experiments were conducted in Sete Lagoas, MG, under natural infestation, during the second cropping season in a randomized complete block with 3 replicates. The plants were evaluated regarding to stand, maturity cycle, plant height, and number of broken or lodging stalks and yield. The borer incidence, number of galleries, number of healthy and damaged nodes were also evaluated to calculate the Infestation Index and Intensity Infestation Index. Among the commercial sorghum hybrids, Br 304 and CMSXS 9701 were the least infested wile Z 732 and Esmeralda were the least damaged. Among the lines, the least infested was 9815017 and least damaged 9816003. The two indexes were correlated positively with plant height in both experiments and negatively correlated with the lines cycle. However, there was no correlation between the Indexes for the hybrids. Among the lines the data fit to a logarithmic curve. Although there is a significant variability among commercial sorghum hybrids regarding sugarcane borer susceptibility, under high borer density, a significant yield loss can be computed to all hybrids. On the other hand, the genetic variability regarding sugarcane borer resistance among the sorghum lines indicated a significant potential for use in a breeding program of resistant cultivars.

Agronomic traits, ensilability and nutritive value of five pearl millet cultivars grown in a Brazilian semi-arid region.

Pearl millet (Pennisetum glaucum(L.) R.) could play an important role as a feed source for ruminants in arid and semi-arid zones of the world owing to its high yield and drought tolerance. The current paper assessed the agronomic characteristics, ensilability, intake and digestibility of five Brazilian pearl millet cultivars (IPA Bulk1BF, BRS 1501, CMS-03, CMS-01 and BN-2) in a typical Brazilian northeastern semi-arid climate. Forage was harvested at the dough stage of grain maturity (growth stage 86 according to the BBCH scale) and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 25 Santa Ines male lambs. The cultivars CMS-01, CMS-03 and BN-2 out-performed the others in terms of dry matter (DM) and digest- ible DM yield/ha. At DM partitioning among plant tissues, the cultivar IPA Bulk1BF had a greater DM associated with panicles and one of the greatest concentrations of organic matter, lactic acid and in vitro dry matter digestibility among the five cultivars. The cultivar BRS 1501 had greater butyric acid concentration as well as one of the highest pH values. Silage produced from BN-2 not only contained greater acetic acid concentration, but also showed one of the greatest total volatile fatty acid concentrations. There were no differences in feed intake and digestibility of nutrients and fibre fractions across all cultivars. Silage made from BN-2 resulted in greater urinary excretion of nitrogen than those produced from BRS 1501. Under the conditions of the present study, the results obtained for production of DM and digestible dry matter, and the ratio of plant fractions, indicates the possible use of these cultivars for silage production in the Brazilian semi-arid region.

Intake and digestibility of sorghum (Sorghum bicolor, L. Moench) silages with different tannin contents in sheep 1

The purpose of this study was to evaluate the voluntary intake and digestibility of three sorghum (Sorghum bicolor, L. Moench) hybrid silages in sheep. The hybrids used were H1 - BRS 655 (CMSXS 222 A × CMSXS 235 R), with tannin; H2 - (ATF54 A × CMSXS 235 R), without tannin; and H3 - BRS 610 (CMSXS 232 A × CMSXS 234 R), without tannin. The intake and digestibility of dry matter (DM), gross energy (GE), neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude protein (CP) were measured. Eighteen crossbred sheep weighing 59.4 kg (±8.3) were used in the trial. A completely randomized design with three treatments (hybrids) and six repetitions (sheep) was used. There were no differences in the DM intake or apparent digestibility among the hybrids. Silage of hybrid BRS 610 displayed higher digestibility coefficients for CP, NDF, ADF, and GE compared with the other silages, which did not differ from each other. The neutral detergent fiber, ADF and digestible energy (DE) intakes were similar among the hybrids silages. All of the hybrids resulted in a positive N balance in sheep. The levels of DE were superior in hybrid silage BRS 610 in comparison with the other hybrids. Sorghum hybrid BRS 610 silage exhibited superior nutritional value compared with the other hybrids, which is most likely in part due to the absence of tannins. Sorghum silage made with hybrid BRS 610 (CMSXS 232 A × CMSXS 234 R) presents superior gross energy, crude protein, neutral detergent fiber and acid detergent fiber digestibility coefficients, as well as greater digestible energy levels than BRS 655 (CMSXS 222 A × CMSXS 235 R) and (ATF54 A × CMSXS 235 R).