Influência de fatores antinutricionais da leucena (Leucaena leucocephala e Leucaena cunningan) e do feijão guandu (Cajanus cajan) sobre o epitélio intestinal e o desempenho de frangos de corte

Um experimento foi conduzido para avaliar a influência de fatores antinutricionais de alguns alimentos sobre o epitélio intestinal e o desempenho de frangos de corte. Foram utilizados 480 pintos de um dia de idade, em um delineamento inteiramente casualizado com quatro tratamentos (A = ração testemunha à base de milho e soja; B = ração contendo Leucaena leucocephala - 6% [LL]; C = ração contendo Leucaena cunningan - 6% [LC] e D = ração contendo feijão guandu - Cajanus cajan - 20% [CC]), quatro repetições e 30 aves por unidade experimental. Houve redução de ganho de peso e aumento da conversão alimentar com a utilização de LL e LC, no período de 1a 21 e de 1a 42 dias de idade. Aos 21 dias de idade, observou-se aumento no tamanho dos vilos do jejuno e na relação vilo:cripta do jejuno e íleo, nas aves que receberam LC. Houve aumento significativo (P<0,05) das células caliciformes no duodeno e jejuno em aves de todos os tratamentos e apenas LL e LC aumentaram as células caliciformes do íleo. Aos 42 dias de idade, houve aumento no número de células caliciformes causado por CC no duodeno e por LL, LC e CC no íleo. O consumo de ração e a profundidade de cripta não foram influenciados. A alteração da morfologia da vilosidade do jejuno, bem como a alteração na relação vilo:cripta no período inicial, influenciou negativamente o ganho de peso e a conversão alimentar nos períodos inicial e total.

Efeitos de emurchecimento, formol, ácido tórmico e solução de Viher sobre a qualidade de silagens de capim-elefante, cultivares Mineiro e Vruckwona.

As cultivares Mineiro e Vrockwona do capim-elefante (Pennisetumpurpureun Schum) foram cortadas aos 75 dias de desenvolvimento, ensiladas em tambores metálicos e submetidas a quatro tratamentos: 1. Emurchecimento ao sol por oito horas; 2. Adição de 0,5% de formal ao material seco e picado; 3. Adição de 0,5% de ácido fórmico (85%); e 4. Adição de 0,2% da solução de "Viher" (70% formal + 26% ácido fórmico + 4% água). Quando o tratamento adotado foi o emurchecimento, os teores de carboidratos solúveis foram suficientes para produzir silagens láticas com baixos teores de pH, e ácidos acético e butírico. Na ensilagem das duas cultivares do capim-elefante, cortadas aos 75 dias de desenvolvimento, houve necessidade de se elevar a dose da solução de "Viher" para que se evitasse a obtenção de silagens inferiores.

Variação na estrutura da vegetação de duas cultivares de Panicum maximum jacq. (colonião e tabiatã) submetidas a diferentes tipos de manejo. Composição em proteína bruta e digestibilidade In vitro da matéria seca

This work was carried out at FCAV-UNESP, Campus of Jaboticabal, Brazil, to study the effects of nitrogen fertilization (0 and 50 kg N/ha/cut), three sucessive periods of growth (December 21st 1987, January 25th 1988 and February 29th 1988)) and three cutting ages (28, 35 and 42 days) on composition in crude protein and in vitro dry matter digestibility of two cultivars of Panicum maximum Jacq. i.e., Coloniao and Tobiata. Plants were harvested in five vertical layers above soil level (0-20, 20-40, 40-60, 60-80 and over 80 cm). The samples were divided in: green leaves, green stems and dry material. Generally, values of in vitro dry matter digestibility and the levels of crude protein of both cultivars were greater in the higher layers of the vegetation, with a decrease, however, for the other layers and more advanced phases of plants development, mainly with no N fertilization.

Produção e qualidade da forragem aproveitável de cultivares de guandu durante o período seco

This work was carried out at Boa Esperanca Farm, sited in Jeriquara, Northeast of São Paulo State aiming to study seven cultivars of Pigeonpea (Cajanus cajan (L.) Millsp). Ramdomized blocks design were used in a split-plot scheme studying the following cultivars: Empasc 307, Fava Larga, Branco de Minas, ICPL 304, ICPL 85063, ICPL 270 and LGR 30, being the last four of them of Indian origin. Cultivars were cut three times during the period May-October, 1992. These cuts were done every twelve weeks, when leaves, flowers, pods and branches were harvested with diameter equal or smaller than 6 mm; the set of these fractions was considered available forage. Results showed that the cultivars, except Empasc 307, always revealed higher percentage of leaves and, consequently, higher dry matter production of this fraction in relation to total available forage. The available forage production, as well as the crude protein and acid detergent fiber percentage and in vitro dry matter digestibility allow to recommend the LGR 30, ICPL 304, Branco de Minas and ICPL 270 cultivars as the most promising ones for utilization as protein banks to be used during dry season.

Produção e qualidade de raiz tuberosa de cultivares de batata-doce no Oeste do Paraná

The objective of this work was to evaluate sweet potato cultivars with starch processing capability, on two cultivation periods, in the western region of Parana (Brazil). Sweet potato was grown at Marechal Candido Rondon, Parana State (24 degrees 33'40 '' S and 54 degrees 4'12 '' W), at a mean annual temperature between 14 and 28 degrees C. The experiment was designed in complete randomized blocks, in a factorial scheme of 4 cultivars (CNPH 003, CNPH 004, Brazlandia Roxa, and Brazlandia Rosada) and 2 cultivation periods (115 and 183 days), with four repetitions. The evaluated parameters were the root productivities (t ha(-1)) and the physical and chemical root composition (humidity, pH, acidity, starch, total soluble sugars and fibers). Data was submitted to all analysis of variance (Anova) and the means were compared by the Tukey test at 5% of probability, Results indicated that sweet potato yield at the cultivars was higher during the 183 day cultivation period (average of 9.14 t ha(-1)) than during the 115 day cultivation period (average of 4.25 t ha(-1)). Thus the CNPH 003 cultivar seems to be a better indication for starch extraction, due to the lowest fiber content in the root, the driest mass content and the largest yield of starch per area.

Cultivares de trigo submetidas a déficit hídrico no início do florescimento, em casa de vegetação

The water restriction can damage the performance of crops, especially in the flowering period. Thus, the aim of this research was to evaluate the response of genotypes of wheat submitted to water deficit in the beginning of flowering. The experiment was conducted in greenhouse, in a completely randomized design, in factorial scheme 3 x 2, with five replications. The factors studied were: three wheat cultivars (Coodetec (CD) 105, 108 and 111) and 2 irrigation managements (with and without imposition of water deficit). During the period of water deficit imposition, gravimetric soil moisture and the relative content of water in leaf were evaluated, while at the moment of rehydration the biometric variables were determined. At the end of the crop cycle the components of production were evaluated. Reduction was found in the gravimetric soil moisture, in the relative levels of water and in all biometric variables, in function of the water deficit. The grain production showed difference only among the water regimes, in which the cultivar CD 111 is more efficient in the maintenance of the productive potential in conditions of water deficit, through the quick recovery in the relative content of water in leaves.

Crescimento radicular e aéreo de cultivares de arroz de terras altas em função da calagem

This work aimed to evaluate root growth, shoot development and nutrient absorption efficiency by rice cultivars Caiapo and Maravilha as affected by lime application. The experiment was carried out in a greenhouse, with treatments set up by Caiapo and Maravilha cultivars in combination with the base saturation (V%) of 10%, 40% and 70%. The experiment was in a randomized complete block design, with four replications. The number of tillers, root length, root dry matter, leaves and stems, leaf content and macronutrients absorption efficiency were evaluated. Comparing cultivars, Maravilha cultivar presented higher root dry weight, root length, number of stems, dry matter of stems and shoot than Caiapo cultivar, as well as accumulated more nutrients in the shoots. on the other hand, nutrient contents were higher in the cultivar Caiapo compared to Maravilha. Maravilha cultivar shows greater root and shoot growth while Caiapo shows higher nutrient absorption efficiency from the soil. The base saturation of 40% is the most effective for both cultivars.

Tolerância de diferentes cultivares de cana-de-açúcar (Saccharum spp.) a herbicidas

This work aimed to evaluate the tolerance of sugarcane cultivars to sulfentrazone, imazapic, isoxaflutole, clomazone and ametryn + trifloxysulfuron-sodium. The experiment was arranged in a randomized block design in a split-plot scheme. The cultivars were allocated to the plots and the herbicides to the sub-plots (five 8.0 m long rows and 1.5 m spacing, with 4 repetitions. The herbicides sulfentrazone (0.8 kg ha(-1)), imazapic (0.147 kg ha(-1)), isoxaflutole (0.1125 kg ha(-1)), clomazone (1.1 kg ha(-1)), ametryn (1.463 kg ha(-1)) + trifloxysulfuron sodium (0.037 kg ha-1) and control were evaluated on 3-yr-old ratoons of the cultivars IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, IAC86-2480 and RB72454 in post emergence. The traits evaluated were: plant toxicity symptoms in the plant leaves; total chlorophyll content and photochemical efficiency (Fv/Fm) at 15, 30 and 60 days after application (DAA); height (cm) at 30 and 270 DAA, and plant stand (stalk m(-1)) at 30 and 180 DAA. Diameter (cm), estimated productivity (t ha(-1)) and quality analysis were evaluated at 270 DAA. The sugarcane cultivars IACSP94-2094, IACSP93-3046, IACSP94-4004, IAC86-2480, RB72454, and IACSP94-2101 especially, were susceptible to clomazone up to 30 DAA, due to leaf chlorosis and lower chlorophyll content, but had no effect on quality characteristics and productivity. The cultivars were also tolerant to other herbicides.

Determinação bromatológica de Pleurotus ostreatus cultivado em resíduos de diferentes cultivares de bananeira

The objective of this work was to evaluate the nutritional composition (raw protein, ether extract, raw fiber, FDA, FDN and ash) of the POS 09/100 strain of Pleurotus ostreatus grown in three combinations of residues (pseudo-stem, leave and pseudo-stem + leaf) and four banana tree cultivars (Thap maeo, Prata ana, Pelipita and Caipira). The basidiomata harvested were submitted to dehydration in a forced ventilation stove with temperature adjusted to 40 degrees C until reaching constant weight, being then grinded in a knife mill. The method proposed by Kjeldahl (1883) was used to determine total nitrogen. The Weende method (AOAC, 1997) was employed to determine crude fiber, acid-detergent fiber (ADF) and neutral detergent fiber (NDF). According to the results obtained, crude protein, ash, ADF and NDF contents varied with the kind of residue and banana tree cultivar; the substrate prepared with leaves of banana tree (Prata Ana cultivar) yielded the highest crude protein (35.4%) and ash (6.7%) contents in the basidiomata of P. streams; the substrate prepared with pseudo-stein of banana tree (Prata Ana cultivar) provided the highest ADF (31.6%) and NDF (41.9%) contents in the basidiomata of P. ostreatus. Ether extract and crude fiber contents of P. ostreatus didn't vary in function of the treatments, with averages of 2.45 and 11.27%, respectively.

Estresse hídrico induzido por manitol em cultivares de algodão

The main goat of this work was to evaluate the effects induced by mannitol- water stress in the initial growing of cotton plants. The experiment was conducted as a completely randomized design, in factorial design 4 x 5, with 3 replications. Treatments were generated by the combination of four cotton cultivars (LD CV Frego; LD CV 02; FMT 701 and IAC 25) and five levels of water stress (0; -0.3; -0.6, -0.9 and -1.2MPa), obtained with mannitol solutions. Water potentials of -0.9 MPa reduced significantly the rate of cotton plants growth. The decrease of the water potential reduced the production of dry mass of the aerial part of all cultivars and increased the production of root dry mass on -0.6MPa potential. LD CV 02 cultivar exhibited a superior performance under water stress.

Selenato e selenito na produção, nutrição mineral e biofortificação com selênio em cultivares de alface

SELENATE and SELENITE on YIELD, MINERAL NUTRITION and BIOFORTIFICATION WITH SELENIUM IN LETTUCE CULTIVARSSelenium is an important antioxidant element associated with physiological processes in plants, microorganisms, animals, and humans. However, its mode of action and essentiality in plants are still disputed. In Brazil, information on Se in agricultural crops is extremely scarce, though there are indications that low levels of Se are being consumed by the population. The objective of this study was to evaluate the effect of selenate and selenite on yield, mineral nutrition and biofortification with Se of lettuce cultivars. The experiment was arranged in a completely randomized factorial design 5 x 3 x 2, with five lettuce cultivars (Maravilha de Verao, Rafaela, Great Lakes, Veneranda, and Vera), three Se concentrations (0, 10 and 20 mu mol L(-1)) and two forms of Se (selenate and selenite), with four replicates. Results indicate that selenate application is more appropriate for biofortification of lettuce cultivars, while the effect of selenite proved to be more toxic. The application of selenate results in increased S shoot concentrations, while selenite reduced P concentrations, and both Se forms decreased micronutrient concentrations. No genotypic variation among lettuce cultivars was observed for Se concentration, and little variation was observed for shoot dry matter yield and S, Mg, Mn, and Fe levels.

Germinação da semente e produção de mudas de cultivares de alface em diferentes substratos

The aim of this paper was to evaluate the effects of the combinations of substrata on germination and development of seedlings of lettuce cultivars. The experiment was carried out in a nursery, in Mato Grosso do Sul State University. There wend compared the following combinations of substrata: washed sand + earthworm humus (2: 1); manure bovine + earthworm humus (2: 1); Plantmax(R) + earthworm humus (2: 1); washed sand + Plantmax(R) (2: 1) and manure bovine + Plantmax(R) (2: 1), and three lettuce cultivars: Crespa sem cabeca, Americana Julia and Baba de Verao. The experimental design was entirely at random, in a 5x3 factorial outline, with four replications and 16 seeds perplot. There were considered for evaluation 10 central seedlings per plot. The characteristics evaluated were: germination percentage (%), index of germination speed (IVE) and dry mass of the whole seedling (g). For all the analyzed variables, the cultivars Baba de Verao and Crespa sem cabeca presented the best results. Manure + humus was the best substratum to obtain seedling with larger development (vigor), althout it did not increase IVE and germination percentage.

Efeito alelopático de extrato aquoso de folhas de Azadirachta indica A. Juss. em alface, soja, milho, feijão e picão-preto

The family Meliaceae has been identified as one of the most promising for biological control, as most species have biologically active compounds. Among the species, the Neem (Azadirachta indica A. Juss) is that stands out most for its efficiency and low toxicity, and it is utilized to control insects, fungi and nematodes. The aim of this work was to verify the allelopathic potential of aqueous extract of fresh leaves of Neem on germination of lettuce, soybeans, maize, beans and Bidens pilosa, as a way to control this weed. The extract was obtained by grinding 200g/L of fresh leaves of the Neem (considered extract 100%) and diluting in distilled water at concentrations of 80, 60, 40, and 20%, and a control with only water. The seeds were kept in the germination chamber at a temperature of 25 degrees C, with photoperiod of 12 hours of light. The aqueous extract affected the germination percentage and average length root of lettuce, with values of 1% and 0.1, cm respectively. For the soybeans, the extract influenced negatively the average time of germination and average speed of germination. There was a drastic reduction of the average root length at higher concentration for soybean, corn and beans. For Bidens pilosa all the parameters analyzed were negatively affected, which means sensitivity to the extract. The bioassay performed in the laboratory showed that the aqueous extract of fresh leaves of Azadirachta indica has allelopathic effect on all species.