The growth regulators have been used in different cultures as cultural management technique that aims to reduce the size of the plant and also provide physiological changes that promote increases in grain yield. The objective of the study was to evaluate the effects of paclobutrazol on growth and yield performance of soybeans grown under different plant densities. The experimental design was a randomized block in factorial scheme (2 × 4 × 4), with four replications, two populations of plants (250 and 450.000 plants ha - 1 ), four doses of the plant growth regulator paclobutrazol (0, 12.5, 25.0 and 37.5 g ai ha - 1 ) and four stages of application (V 3 , V 6 , R 1 and V 3 + R 1 ). Averages for the effects of stadiums applications and plant populations underwent Scott Knott test at 5% probability of doses and the regulator to regression analysis. The population of 450.000 pl ha - 1 resulted in greater plant height, lodging and most lower productivity of soybeans. The use of paclobutrazol at V 3 soybean crop did not reduce plant height or grain yield, but reduced the percentage of lodging, and in the stadiums full development of culture (V 6 ) or early reproductive period (R 1 ) reduced height and lodging, as well as the grain yield of the crop. Increases in doses regulator paclobutrazol resulted in reducing plant height, lodg- ing and grain yield of soybean.

In massal rearing of natural enemies with the goal of biological control, the procedures adopted for establishment and maintenance of the individual founders of the colonies may have undesirable effects on population genetic structure of laboratory. This situation influences the success of rearing and effectiveness in the field. The objective of this study was to evaluate, along of generations two laboratory populations (Jaboticabal and Piracicaba) of Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae), founded with different numbers of adults (1, 5, 10, 15 and 20 couples), the frequency of morphological variants, size of wings and eye color, such as parameters for inferences about the homozygosity degrees. For eye color were assessed the frequency, while for the size of wings was measured the width and the length of the right mesothoracic wings. The eye color variants for C. externa populations may be monitored in the laboratory aiming at detecting inbreeding, whereas the measurements of length and width of wings should not be adopted for this purpose.

The aim of this study was evaluate the agronomic p erformance of common bean cultivars ac- cording to phosphate fertilizing in the south of To cantins State. The experimental design was randomiz ed blocks with four replications. The treatments were constituted by 19 common bean cultivars submitted t o low and high levels of phosphorus in the soil (20 and 1 20 kg ha -1 of P 2 O 5 at planting, respectively). The increase of phosphorus promoted an addition in average of plant height, height of insertion of the first pod, stem diameter, number of pods per plant, number of grains per pod, number of grains per plant, weight of hundreds gra in and grains yield an cultivars IAC-Centauro, IAC-Galante , IPR-Juriti and IPR-Eldorado . The cultivars IAC-U na and IPR-Siriri present higher grains yield when sub mitted to the application of 120 kg ha -1 of P 2 O 5 .

This study was developed with the purpose of evaluating the protein fractionation and in vitro di- gestibility of the dry matter (IVDMD) of millet genotypes for grazing, managed at different heights and sub- jected to several cuts. The experiment had a randomized complete block design, with repeated measures over time, four replications in a 3x3 factorial arrangement, with three cultivars of millet (ADR 500, LAB 1542 and LAB 1838) and three average cutting heights (60; 80 and 100 cm). Evaluations were undertaken through cuts in the same plots during four months. Results showed that millet genotypes were similar as for the values of pro- tein fractionation and IVDMD. The forage quality is affected by the management of cutting height, thereby it is not recommended to manage millet genotypes at 100 cm height for providing lower fraction A, B1, B2 and digestibility and higher fraction B3 and C of the forage.

The study aimed to examine the response of cowpea Vinegar cultivarwith inoculation of rhizobia and Trichoderma spp. at cerrado environment in Gurupi – TO, in the years of 2011 and 2012. The experiment was conducted under field conditions and experimental design of randomized blocks, corresponding to the treatments: inoculation with rhizobia and Trichoderma spp. in the seed; the seed inoculation with rhizobia and Trichoderma spp. in the soil; the seed inoculation with rhizobia and Trichoderma spp. in the seed and soil; only inoculation with rhizobia; fertilized with nitrogen; and control non-inoculated and non-fertilized with nitrogen. Inoculation was performed with the rhizobia strains INPA 03-11B and UFLA 03-84. For treatments with Trichoderma spp. was used to inoculate commercial Trichoplus JCO powder formulation. The results indicated that the potential for nitrogen fixation of rhizobia strains tested, and the Trichoderma bioprotection was of fundamental importance for biomass, production, nodulation and yield, which may be related with the effective capacity to supply nitrogen and protection against pathogens. Generallythe inoculation with rhizobia and Trichoderma in the seed and soil, provided better results on the variables analyzed for both season, with higher productivity than other treatments

The objective was to evaluate the cellulolytic activity of aerobic mycelian fungi from dairy cat- tle fed tropical forages. Isolates of fungi were obtained from 30 samples of rumen fluid from cows fed sorghum silage, 32 cows fed on Brachiaria brizantha , 12 heifers receiving sorghum silage and 11 heifers fed cane sugar. The isolation was performed on C solid medium containing cellulose. Were evaluated 49 isolates, 27 Aspergil- lus spp., four Gliocladium spp., six Paecilomyces spp., nine Rhizophus spp. and three Scedosporium . These isolates were incubated in C medium with 1% microcrystalline cellulose as the sole carborno source, and incu- bated at 37°C in triplicate. Cellulolytic activity indices were verified after 24, 48 and 72 hours and calculated by the ratio between degradation halo and colony diameter for comparing in nonparametric tests. The genus Aspergillus , showed higher cellulolytic activity index mean compared to Rhizophus genus (p <0.05). Eight iso- lates of Aspergillus spp. and six of Paecilomyces spp. showed this index higher than one, indicating potential for utilization in ruminant nutrition.

In semiarid regions the irrigation is essential for obtaining high yields and fruit quality of pine- apple. The objective of this work was to evaluate the vegetative characteristics, fruit and slips production and fruit quality of pineapple, under different drip irrigation depth. The experiment was conducted in a randomized block design with five treatments replacement of class A evaporation pan (PAN), with 4 replications. The vege- tative growth, flowering, production and fruit quality and slips production were evaluated. The plants of pine- apple that have received regarding the irrigation at 30, 50, 70, 100 and 150% of PAN do not differ for the char- acteristics of productivity, fruit weight with and without crown diameter and fruit length, skin color, total solu- ble solids (TSS), total titratable acidity (TTA), TSS / TTA and pH of the pulp. The pineapple 'Perola' has greater vegetative growth in irrigation depth applied between 67,1 and 79,1% of PAN. The natural flowering cumulative total is greater in depth corresponding to 70% of PAN. The slips production per plant and slips pro- ductivity is greater in depth corresponding to 85% of PAN.

For applications in water management, estimation of evapotranspiration is a critical term in the water balance, to establish a sustainable development of activities that requires such action. So it is necessary to more accurately estimate the reference evapotranspiration (ETo). The objective of this study was to evaluate the performance of daily ETo values obtained for 12 empirical methods by comparing them with the Penman- Monteith FAO. The meteorological data used for the empirical models were measured in the National Institute of Meteorology automatic meteorological station installed at the experimental station in Rafael Fernandes, Federal Rural University of Semi-Arid, Mossoró, RN. Even with some methods presenting divergences from the standard method in the months of the highest water demand with an absolute error of approximately 0.99 to 1.67, it could infer that the most suitable methods based on the performance index greater than 0.76 were: Benevides and Lopez (1970), Linacre (1983), Bruin (1979), Jensen and Hayse (1963) and Priestley and Taylor (1972), in that order, thus it may represent satisfactorily the ETo. The methods that require fewer climatic elements such as Benevides and Lopez (c = 0.85) and Linacre (c = 0.79) performed better than more complex to estimate ETo in daily periods at any time of year.

Combretum leprosum Mart. is a tree species native of the Caatinga, used in the restoration of degraded areas and in folk medicine. Thus, this research aimed to evaluate the germination and vigor of the seeds subjecting them to different pre-germinative treatments, temperatures and substrates. In the first experi- ment, we tested the pre-germinative treatments: mechanical scarification with sandpaper, chemical scarification with H2SO4 for 1, 5, 10 and 20 minutes, immersion in water at 80 oC and imbibition in distilled water for 24 hours, beyond of the control. In the second experiment, after treatment of imbibition in water for 24 hours, the experimental design was completely randomized in a factorial 5 x 4 (five substrates: into paper, sand, coconut fiber, vermiculite and paper towel organized in the form of rolls; and four temperatures: 25, 30, 35 and 20-30 oC). The following parameters were evalueted: seed moisture content, germination, germination speed index, first germination count and seedling length and dry matter weight. The seeds of Combretum leprosum have not coat dormancy. However, pre-germinative treatments of mechanical scarification with sandpaper and imbibi- tion in water for 24 hours allows better expression of seeds vigor. The paper towel and the temperatures of 25, 30 and 20-30 oC provide adequate conditions for evaluating the germination of Combretum leprosum seeds.

To evaluate different organic sources as substrates for the production of rootstocks of Tamarin- dus indica L., we conducted an experiment in a greenhouse nursery located on the campus of Universidade Federal Rural do Semi-Árido (UFERSA) in the period from October 2007 to February 2008. We tested the substrates: soil, manure, goat manure, sheep manure and humus, and combinations thereof, totaling twelve treatments. The experiment was conducted in a randomized block design, with 12 treatments (substrates), four replicates and 10 plants per treatment, totaling 480 plants. The conclusion that the combination of soil with animal manure, in various ratios studied, show satisfactory results in the production of the tamarind rootstock was reached. The treatment not only composed of soil provided suitable for production of rootstocks results of tamarind.