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The objective of this study was to evaluate the productivity, productive efficiency, and nutritional value of the elephant grass cultivar BRS capiacu (Pennisetum purpureum Schum.), managed at four regrowth ages during winter in the semiarid region of northern Minas Gerais, Brazil. A completely randomized design with the elephant grass cultivar BRS capiacu was submitted to four cut intervals (30, 60, 90, and 120 days) in the winter with ten replications, for a total of 40 plots, each with a useful area of 6 × 5 m. There was a linear increase of 76.25% (P

Esta investigação visa avaliar o desempenho de redes neurais artificiais na predição da produtividade da cultura do milho, no município de Jaguari, região Central do Estado do Rio Grande do Sul, com base em variáveis morfológicas da cultura. Para treinamento e validação das redes neurais, foram utilizados dados publicados por SOARES (2010). Foram testadas diversas redes neurais do tipo perceptron, multicamadas com algoritmo backpropagation otimizado (Levenberg-Marquardt). Elas tiveram como variáveis na camada de entrada: índice de área foliar; matéria verde total; altura de planta; e no de planta m-2. Na camada de saída: produção de grãos. Cada arquitetura foi treinada 10 vezes, escolhendo-se, ao final do treinamento, aquela com menor erro relativo médio e menor variância em relação aos dados de validação. A eficiência das redes foi analisada por meio de indicadores estatísticos. A rede com 35 neurônios na camada escondida apresentou os menores erros nos processos de treinamento e validação, dentre as diversas arquiteturas treinadas. Dessa forma, a rede neural com arquitetura 4-35-1 apresenta bom desempenho, sendo eficiente na estimativa da produção de grãos, considerando a região de abrangência do experimento. This investigation aimed to evaluate the performance of artificial neural networks to predict the corn grain yield in the city of Jaguari, Central region of Rio Grande do Sul, based on morphological characteristics of this culture. It was used the data published by SOARES (2010) for training the neural networks. Several multilayer perceptron neural networks with backpropagation-optimized algorithm (Levenberg-Marquardt) were tested. The input layer variables used were leaf area index, total green matter, plant height and number of plants m-2 and the output layer: corn grain yield. Each architecture was trained 10 times, picking up at the end of training the one with lower mean relative error and less variance for data validation. efficiency of the networks was analyzed by means of statistical indicators. Among many architectures trained, the network with 35 neurons in the hidden layer had the lowest error in training and validation processes. In this way, the neural network with architecture 4-35-1 presents a good performance, being efficient to estimate grain production, considering the region covered by the experiment.

The objective of this study was to assess agronomic characteristics and nutritional values of silages of millet genotypes. Planting was done in randomized blocks, with five replicates per genotype. Green matter yield for genotypes ADR 500 and CMS 01 was higher and similar to each other, with 40.16 and 41.36 t ha (p > 0.05). There was no significant difference for dry matter yield, with the mean being 9.93 t ha (p > 0.05). The silages were similar (p > 0.05) as to pH, Aw and N-NH3/TN, presenting values of 3.92, 0.97 and 7.64%, respectively. There were no significant differences (p > 0.05) concerning the bromatological composition of the silages of the different genotypes, with a mean of 30.74% of dry matter, 10.21% for crude protein and 58.69% for neutral detergent fiber (p > 0.05). The dry matter digestibility mean stood at 59.90%. Based on the nutritional values and digestibility of the millet silages, the five genotypes are suitable for silage production, with potential for the North of Minas Gerais.

The experiment was conducted at the Experimental Farm of the Federal University of Mato Grosso in the municipality of Santo Antônio do Leverger, State of Mato Grosso, Brazil to evaluate the agronomic characteristics of corn hybrids in the cultivation of second crop for silage production. The experimental design was carried out with randomized blocks with 23 treatments (hybrids) and three replications. Corn hybrids from different seed companies and recommended for the midwestern region of Brazil, were used. The agronomic traits were: stem diameter (cm), plant height and ear insertion (m); yield of green matter (ton. ha-1), percentage of spike, stem and leaves in green mass; ear productivity (ton. ha-1), dry matter content of stem + leaf and whole plant. Hybrids BF 9304, DKB 370, 177 DKB, BF 9534, BF 9417, AG 5020, BE 9701, P 3021 and P 30F98 had the highest production of green matter, plant height and spike insertion. The hybrid BF 9304 was also prominent for spike percentage (50.55%). O experimento foi conduzido na Fazenda Experimental da UFMT em Santo Antônio de Leverger, Estado do Mato Grosso, com o objetivo de avaliar as características agronômicas de híbridos de milho em cultivo de segunda safra para a produção de silagem. O delineamento experimental utilizado foi em blocos casualizados com 23 tratamentos (híbridos) e três repetições. As características agronômicas avaliadas foram diâmetro do colmo (cm); altura de plantas e da inserção de espiga (m); produtividade de matéria verde (t ha-1); porcentagens de espiga, colmo e folhas na massa verde; produtividade de espigas (t ha-1); teores de matéria seca do colmo + folha e da planta inteira. Os híbridos que apresentaram maiores valores para produção de matéria verde, altura de plantas e da inserção de espiga foram BF 9304, DKB 370, DKB 177, BF 9534, BF 9417, AG 5020, BE 9701, P 3021 e P 30F98. O híbrido BF 9304 também se destacou quanto à porcentagem de espiga (50,55%).

This study aimed to evaluate the agronomic performance of 24 sorghum genotypes in four Brazilian regions and the chemical characteristics of genotypes grown in Sete Lagoas, state of Minas Gerais. Genotypes BRS655 and 12F37005 had higher average production of green matter (> 44 ton ha-1) and dry matter (> 17 ton ha-1), respectively. Genotypes 12F38019, 12F40019, 12F37005, 12F37043 and Volumax took more days to flower in three of the four municipalities (75-90 days). Genotypes 12F38006, 12F40006 and 12F37016 were taller (> 2 m). Values of dry matter, crude protein and neutral detergent fiber ranged from 37.15 to 50.13; 5.51 to 10.28 and 43.57 to 65.69%, respectively. The genotypes were not different regarding acid detergent fiber content, with mean value of 34.83%. Genotypes 12F38019, 12F37016, 12F39005, 12F39019, 12F37007, 12F37014, 12F39014 and BRS 655 showed the best values of dry matter digestibility (64.31 to 74.20%) and crude protein content (8.33 to 10.28%). Among them, 12F139014 exhibited the lowest lignin content (3.32%), suggesting less effect of this fraction on digestibility. Genotype 12F39014 is the most suitable for cultivation, as it presented the best nutritional value and good dry matter production in the four municipalities.

This study had as objective to quantify achenes, leaves, stem and capitulum production and participation, as well as green and dry matter production of two sunflower hybrids for silage production. Two sunflower hybrids, Helio 251 (H251) and Helio 360 (H360), were used and implanted under oat stubble. The counting of twelve points with five linear meters/hectare of each hybrid was carried out to evaluate hybrid production and five samples were taken to evaluate plant composition. A complete randomized experimental design was used and the averages were analyzed by Tukey test. H251 hybrid presented higher plants per linear meter and per hectare (3.99 vs. 3.12 plants/m; 49,953.95 vs. 38,342.10 plants/ha, for H251 and H360, respectively). H360 capitulum were heavier than the ones from H251, when expressed in green (303.79 g/plant) or dry (56.88 g/plant) matter basis, consequently, it showed heavier achenes (151.09 and 100.12 g/plant, respectively, for green and dry matter). H360 presented higher stem weight, when expressed in green (120.95 vs. 61.27 g/plant) or dry (48.58 vs. 29.01 g/plant) matter basis. The higher weights of capitulum, achene and stem presented by H360 resulted in heavier plants and superiority on dry matter production per hectare. KEYWORDS: achenes, capitulum; dry matter; green matter; leaves; stem.

O experimento foi conduzido em área do Centro de Ciências Rurais da Universidade Federal de Santa Maria, com o objetivo de avaliar diferentes tipos de manejo do palhiço e os efeitos sobre a produção de colmos industrializáveis e outras características agronômicas da cana-de-açúcar. Foram testados cinco tratamentos de manejo do palhiço, em quatro colheitas consecutivas. Os tratamentos de queimar a cana em pé antes da colheita, colher a cana e queimar o palhiço remanescente e retirar o palhiço da parcela comportaram-se de maneira semelhante em relação a produção de colmos industrializáveis. Enleirar o palhiço em filas alternadas e triturar o palhiço e redistribuir na lavoura apresentaram menor produtividade. Para o brix pode-se recomendar qualquer dos tipos de manejo do palhiço estudados, visto que todos apresentaram grau brix superior a 18%. A produção de massa verde proveniente das pontas, diâmetro do colmo, peso médio de colmo e número de entrenós do colmo não foram afetados pêlos tratamentos de manejo do palhiço. A field experiment was conducted at Federal University of Santa Maria, RS, Brazil, with objective to study different methods of handling sugarcane trash and its effects on productivity and other agronomic characteristics. It was tested five treatments of sugarcane trash, in four consecutive harvests. Treatments of burning the sugarcane plant before harvest, harvesting and burning the remaining trash and remove the trash from plots behaved the same way in relation to industrialized culms production. Aligning it in alternate rows and triturate and redistribute in the field showed less productivity. In relation to brix % juice, it could be suggest any one method of handling the trash studied, because all them presented brix % juice above 18%. The production of green matter from the upper immature part of the stalk, diameter, mean weight of the culm and internode number was not affected by methods of handling the trash.

Four species of leguminous shrubs endemic to the Canary Islands (Spain) - Chamaecytisus palmensis (tagasaste), Teline canariensis, Teline osyrioides sericea and Teline osyrioides osyrioides - were evaluated from 1999 to 2000 as a source of animal forage. Two experiments were undertaken. Experiment 1 involved wild populations in the natural habitat on the island of Tenerife including germplasm collection and a study of their phenology. Experiment 2 involved the same species, this time in cultivation with a density of 5142 shrubs/ha on an experimental plot (La Laguna, Tenerife) situated at 549 m a.s.l. and with annual rainfall of between 338 and 562 mm. Experiment 2 evaluated plant survival, edible green matter/inedible matter fraction (EGM/IM) and production of edible dry matter (EDM) at three cutting heights (30, 50, 70 cm above ground level). Samples were taken at the end of each season during 2 consecutive years. Production of Chamaecytisus palmensis was significantly higher (P < 0.05) at all three heights than that of the three species of Teline, which had similar productions to each other. However, cutting height did not affect EDM production.

O girassol foi misturado ao capim-elefante (Pennisetum purpureum Schum) na ensilagem. A colheita do capim-elefante foi realizada manualmente após 70 dias do corte de uniformização, à altura de 10 cm da superfície do solo. Para confecção da silagem, foram utilizados os híbridos de girassol M-742 e M-92007. As misturas capim-elefante e girassol foram feitas nas seguintes proporções de matéria verde: 100 e 0%, 75 e 25%; 50 e 50%; 25 e 75%; 0 e 100% de capim e girassol, respectivamente. As plantas foram picadas mecanicamente em partículas de 2,0 a 3,0 cm de tamanho, ensiladas por 30 dias, em silos de "PVC" de dez centímetros de diâmetro e quarenta centímetros de altura. Foram avaliadas as porcentagens de matéria seca (MS), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro (FDN), digestibilidade in vitro da matéria seca (DIVMS) e valores de pH das silagens. O delineamento experimental empregado foi o inteiramente casualizado, com quatro repetições. Concluiu-se que as silagens de capim-elefante com mistura da planta de girassol apresentaram maiores porcentagens de MS, PB, EE e valores de pH, aumentos na DIVMS e menor porcentagem de FDN na matéria seca com o aumento dos níveis de substituição. A mixture sunflower and elephant grass has been used for ensiling. Elephant grass was harvested manually 70 days after a plot leveling a height of 10cm from soil surface. For silage making, the sunflower hybrids M-742 and M-92007 were utilized. The mixtures of sunflower and elephantgrass were done at the following ratios of green matter 100 and 0%; 75 and 25%; 50 and 50%; 25% and 75%;0 and 100%, of grass and sunflower, respectively. Plants were chopped mechanically in particles of 2.0 to 3.0 cm in size, ensiled for 30 days in PVC silos 10 centimeters in diameter and 40 centimeter height. The evaluated variables were as follow: Percentages of dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF) in vitro digestibility of dry matter (IVSDM) and pH values of the silage. The experimental design utilized was the completely randomized with four replicates. It was concluded that the elephantgrass silages mixture with sunflower plant presented the highest percentages of DM, CP, EE and pH values, increases in the IV DDM and a lower percentage of NDF in the dry matter with increasing levels of replacement.

The study was carried out to investigate the effects of different row spaces 15, 30, 45, 60 and 75 cm and seeding rates 40, 80, 120, 160 and 200 kg ha-1 on the hay and crude protein yields of sainfoin at the Agricultural Research and Experiment Center of Agriculture Faculty, Uludag University in 1999-2002. The field experiments were established in a split plot design with four replications. Plant height, stem number per m2, green matter yield, hay yield and crude protein yields were determined. The results suggested that sainfoin should be planted with 15-30 cm row spaces and at 160-200 kg ha seeding rate for hay production in Southern Marmara Region or in regions with similar ecological conditions, Bu araştırma, korungaya uygulanan değişik sıra aralıkları 15, 30, 45, 60 ve 75 cm ve tohumluk miktarlarının 40, 80, 120, 160 ve 200 kg ha-1 kuru ot ve ham protein verimine etkilerini belirlemek amacıyla Uludağ Üniversitesi Ziraat Fakültesi Tarımsal Araştırma ve Uygulama Merkezinde 1999-2002 yılları arasında yürütülmüştür. Araştırma tesadüf bloklarında bölünmüş parseller deneme desenine göre dört tekrarlamalı olarak kurulmuştur. Araştırmada bitki boyu, m2’de sap sayısı, yeşil ot verimi, kuru ot verimi ve ham protein verimi tespit edilmiştir. Elde edilen sonuçlara göre, Güney Marmara Bölgesi’nde korungada ot üretimi için 15-30 cm sıra aralığı ve 160-200 kg ha-1 tohum miktarının kullanılması gerekmektedir

The composition and nutritive value of leaf protein concentrates (LPC) from various cultivars of potato and tobacco, m and various species of lupin, were investigated with special respect to the content and effect of anti-nutritional substances. Biological value (BV) and true digestibility (TD) of proteins were determined in rats using the Thomas-Mitchell balance method. No distinct differences in amino acid composition of proteins extracted from particular plants were found. The nutritive value of concentrates from potato haulm was not correlated either with their amino acid composition or solanine content. LPC from cv. Nysa contained the highest amount of solanine (1015 mg kg−1), but its protein was of the highest biological value (62). Both BV and TD of protein extracted from the leaves of bitter lupin were significantly lower than these from sweet lupin (BV = 50 and 62, TD = 77 and 81, respectively). Nicotine contained in LPC from tobacco had lethal effects on some of the rats. It was concluded that anti-nutritional and toxic substances present in the green matter of plants can penetrate LPCs and in some cases impair their nutritive value. Thus, in vitro tests cannot provide an adequate basis for the prediction of LPC quality.

SUMMARYColchicine induced 64-chromosome white clover was compared at a number of centres with control material (2n = 32), as spaced plants and in broadcast plots with and without companion grasses.The chromosome-doubled material generally conformed to the well-known reaction of polyploids; the plants were later flowering, had thicker petioles and stolons, broader leaflets and spread less vigorously. Yield of green matter of spaced plants was much less, and in broadcast plots the gross yield (grass + clover) and that of the clover fraction was 7% less than in comparable S. 100 plots. The Finlay-Wilkinson analysis indicated that the chromosome-doubled form did not respond to improved conditions to the same extent as did the control varieties. The presence of grass in the mixture partly compensated for low clover yield, but was insufficient to increase total yields to that of S. 100 controls.