The objective of this research was to characterize the spineless forage cactus production in the semi-arid region of Paraiba State in the Northeast of Brazil. Information from 199 interviews carried out in the rural area of municipal districts in the Paraiban Cariri region was used. The interviews were conducted from February 2008 through August 2009. The data were tabulated in a spreadsheet, where a matrix with the ques- tions and answers of each interviewee was established. The production systems were defined using principal component analysis, followed by cluster grouping of quantitative variables. The first three principal compo- nents explained 61.60% of total variation. The application of cluster analysis, based on scores of the three main components, identified four cactus forage groups of producers. The livestock activity prevails on the ag- riculture and it is imposed as an appropriate activity in the production systems of the agriculture sector in the Paraiban Cariri region. The cultivation of forage cactus predominates over other cultivated forage plants, being fully incorporated into the local productive process of Paraiban Cariri region.

The undesirable effects of agrotoxics have aroused the interest of society to use alternative tactics of pest control, as plants with insecticidal activity, which can be used as powders, aqueous and organic extracts, essential oils and emulsifiable. This way, the toxicity, population growth and repellence of aqueous extracts of plants were evaluated on the cassava green mite, Mononychellus tanajoa . Aqueous extracts of Cro- ton blanchetianus , Myracrodruon urundeuva and Ziziphus joazeiro were used, in which were immersed in cas- sava leaf discs (3.5 cm diameter). The extracts at all concentrations (1, 5, 10, 15, 20 and 25%) resulted in a de- cline in the pest population. The concentrations of 20 and 25% of the extracts resulted in the highest percentage mortality of the pest. All extracts in concentrations of 15, 20 and 25% for adult females were repellents M. ta- najoa .

The relative toxicity of the mustard (Brassica rapa L.) essential oil (MEO) on young and old larvae, pupae, and adults of Sitophilus zeamais and Callosobruchus maculatus was determined using concen- tration-response bioassays. The respiration rate of adults was measured to determine its influence on its toxic- ity. Different developmental stages of both species differed significantly in their response to MEO, with the adults being much more susceptible than the immature stages. Although adult mortality did not differ between species, the adult respiration rate of C. maculatus was significantly higher than that of S. zeamais. Thus, the toxicity oil for adults was not influenced by natural respiration rate of species investigated.

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.

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.

This study aimed to evaluate antagonism and metabolites produced by different species of Ba- cillus in the inhibition of mycelial growth in vitro against F. oxysporum f. sp . lycopersici . For evaluating the antagonism of Bacillus spp. F. oxysporum f. sp . lycopersici was performed pairing of fungus and bacteria by the method of the circle. In the method for detection for the quality for thermostable metabolites liquids. Media BD were used for growth of the isolated Bacillus sp. And incubated for 15 days. After this period, was added 3 g of agar in each flask, and autoclaved broth and poured into Petri dishes. In the center of the plates were placed discs culture of the pathogen. The experimental design was completely randomized with 11 treatments and six repetitions in both experiments. Statistical difference was found between the isolate and the control. Special mention to strains B12 ( Bacillus sp.), B41 ( B. cereus ), B22' ( B.pentothenticus ), B45 ( B. cereus ), B47 ( B. cereus ) that exhibited the lowest average diameter of the colony. To study the inhibition of mycelial growth of F. oxysporum f. sp. lycopersici by thermostatable metabolites five differ statistically from the control they are: B35 ( B. pumilus ), B47 ( B. cereus ), B22' ( B. pentothenticus ), B12 ( Bacillus sp.) and B41 ( B. cereus ) the latter two treatments showed the best results of the pathogen colony diameters and 3.81 to 2.89 cm, respective- ly. B12 and B41 Isolates showed that their antibiotic products were able to inhibit 67.88 % and 57,66 % of F. oxysporum f. sp. lycopersici . These results highlight the possibility of using isolates of the genus Bacillus in the fight against fusarium wilt in tomato.

In order to quantify the growth, accumulation and exportation of macronutrients by carrot ‘Forto', and obtain equations that best represent them, it was conducted an experiment in the São Gotardo (MG), from May to September 2004. Samples were taken at 40, 50, 60, 70, 80, 90, 100, 110 and 120 days after sowing (DAS) to determine dry matter and accumulation of macronutrients in leaves and roots. At 40 DAS, five days after thinning, the plants had 0.18 g and 0.04 g in dry leaves (LDM) and of roots (RDM), respectively. From then, until 88 DAS, the partitioning of photoassimilates and accumulation of matter in the shoots were more pronounced. The RDM was low until 80 DAS, which corresponded to two thirds of the crop cycle, from when the amount of material allocated in this part of the plant had strong growth, surpassing, at 88 DAS, the amount of LDM. The nutrient accumulation was small in the first 60 DAS, coinciding with the period of lower dry matter accumulation. The order of decreasing macronutrient accumulation by the crop were: K > N > Ca > P > S > Mg, in the amounts of 906.7, 438, 155.46, 87.4, 58 and 37.63 mg plant-1, respectively. The root participated with 60.5% of the accumulation of N, 86.1% of P, 58% of K, 25.5% of Ca, 55.6% of Mg and 65.5% of S. Considering a population of 590,000 plants per hectare, the total quantity of nutrients by the crop of carrots was 258.3, 51.6, 534.8, 91.7, 22.2 and 34.2 kg N ha-1, P, K, Ca, Mg and S, respectively.

The objective of this work was to obtain informatio n about the best sources and doses of nitro- gen and potassium fertilizers for obtaining vigorou s rootstocks umbuzeiro in Northeastern Brazil. In s eparate experiments, we tested two sources of nitrogen, ure a and ammonium sulfate and five N rates (0, 350, 70 0, 1400 and 2800) mg.dm -3 , and two sources of potash fertilizer (potassium c hloride and potassium sulfate) in five doses of K20 (0, 1.800, 3.600, 5.400 and 7.200) mg. dm -3 substrate. The experimental design was in random- ized blocks in factorial 2 (sources) x 4 (doses), w ith ten treatments and four replications and ten pl ants per plot. Parameters were evaluated for the growth of seedlin gs. Doses of nitrogen and potassium applied to soi l had a negative influence in the survival of seedlings, shoot length, stem diameter and root fresh weight of seedlings.

Cowpea [Vigna unguiculata (L) Walp] have great social and economic importance for the Para State. It grows well in areas with low precipitation and two crop cycles can be obtained annually. This study aimed to assess the effect of the residual fertilization from a previous culture (Sorghum bicolor L. Moench) and crop systems on cowpea yield and macronutrient concentration on leaves of three cowpea cultivars (BRS- Milênio, BRS-Urubuquara e BRS-Guariba). The study was conducted at the UFRA. The treatments were two crop systems (minimum tillage and conventional), four levels of potassium (50, 100, 200 e 300 kg de KCl ha-1 applied to a previous sorghum culture) and the three cowpea cultivars. Treatments were organized as a three (4 x 2 x 3) factor experiment on a randomized complete block design. The soil was a yellow latosol. In each ex- periment plot five plants were selected to determine shoot dry matter and foliar nutrient concentration. Grain yield was determined after harvesting all plants on the experiment plot. The residual KCl fertilization affected foliar nutrient content, but did not affect shoot dry mass or yield of grain. Yield was higher in the minimum tillage system. Highest yield (1590 kg ha-1) was recorded int the cv. ‘Guariba’ when 100 kg of KCl ha-1 had been used in the previous crop. The highest content of leaf N and K was found in cowpea under minimum till- age system. The amount of P and Mg were higher in the conventional system whereas the amount of Ca did not change.

The work aimed to evaluate the influence of potassium rates on the yield of yam (Dioscorea cayennensis) and determine your rate for the productivity of commercial tubers. The experiment was conducted at the Federal University of Paraíba, in Areia-PB, in the period from February to December 2010. The experimental design was randomized complete blocks with six treatments comprise the doses of 0; 50; 100; 150; 200 and 250 kg ha-1 of potassium, in four repetitions. Were evaluated the average mass of commercial tubers, productivity of commercial tubers, percentage of tubers classified as first, the leaf content of potassium in the leaves and the maximum rate of economic efficiency. The maximum average mass of commercial tubers was 2.60 kg, obtained at rate of 126 kg ha-1 of potassium. The rate of 189 kg ha-1 of potassium was responsible for maximum productivity commercial of 17.7 ha-1 t of tubers. The maximum percentage of tubers classified as first was 88%, achieved at a rate of 171 kg ha-1 of potassium. The maximum content of potassium in the leaves of yam was 22.3 g kg-1 obtained at a rate of 155 kg ha-1 of potassium. The maximum rate of economic efficiency of potassium for commercial productivity of tubers was de184 kg ha-1.