The systems of harvesting sugar cane can cause changes in fertility, quantity and quality of organic matter and the degree of oxidation, altering soil carbon stocks. Given this context, the objective was to evaluate the production of dry biomass (DB), soil fertility, the content of total organic carbon (TOC), the car- bon in particle size fractions (particulate organic carbon (COp) and organic carbon associated with minerals (COam)) and oxidizable organic matter fractions (F1, F2, F3, F4 and F1 / F4) in manual harvesting (CMa) and mechanized (CMe) of sugar cane. The sampling for biomass production was conducted in area of 1 m 2 at four points per plot, soil samples were collected at depths of 0.00 - 0.05; 0.05 - 0.10; 0.10 - 0.20 and 0.20 - 0.40 m. The average annual production of dry biomass in the area CMe was 17 times higher when compared to the area of CMa; The pH and phosphorus content was significantly lower in the larger depths area CMa when compared with that of Cme; the harvesting system caused significant CMe in TOC, COp and COam depth 0.00 - 0.05 m increases when compared to the CMa system; There were not significant differences in the oxidizable fractions (F1, F2, F3 and F4) of the organic carbon in the areas of CMa and CMe.

It is proposed to evaluate the growth of tomato plants grown in soil covered with different types of material. The experiment was conducted at WG Fruit Farm in Baraúna-RN during the period from July to November 2008. The experimental design was a randomized complete block with four replications. The treat- ments were arranged in split plots. The plots were the types of ground cover: bare soil (control), black polyeth- ylene film (double-sided black), silver polyethylene film (double-sided black and silver), white polyethylene film (double-sided black and white) and black row cover (TNT), and the subplots sampling dates of plants of the hybrid tomato Mariana at intervals of fourteen days, from the seedling stage (14, 28, 42, 56, 70, 84 and 98 days after transplanting, DAT). The plants were harvested in the surface area of each plot, partitioned into leaves, stems, flowers clusters and fruit, and placed in an oven with forced circulation at 65 oC, until constant weight is gotten. The characteristics assessed were: dry matter accumulation of leaves, twigs, flower clusters, fruit, total leaf area and leaf area index. Based on the dry mass of leaves, twigs, flower clusters, fruit and total, it was quantified partition of treated tomato grown in different mulching. Mulching treatments affected the growth of tomato plants with black row cover, white polyethylene and bare soil registering the highest mean of total dry matter, leaf area and leaf area index. The maximum leaf area index was obtained at 71 DAT in the treatments with black row cover (2.88), non-covered soil (2.36), white polyethylene (2.21), 77 DAT in silver polyethylene (2.17) and black polyethylene (1.72). At the end of the cycle, the plant has accumulated a mean of 28.30%, 11.98%, 3.92% and 55.82% of dry leaves, twigs, flowers and fruit clusters, respectively. Key words: Solanum lycopersicon L, dry mass accumulation, assimilate partitioning, leaf area.It is proposed to evaluate the growth of tomato plants grown in soil covered with different types of material. The experiment was conducted at WG Fruit Farm in Baraúna-RN during the period from July to November 2008. The experimental design was a randomized complete block with four replications. The treat- ments were arranged in split plots. The plots were the types of ground cover: bare soil (control), black polyeth- ylene film (double-sided black), silver polyethylene film (double-sided black and silver), white polyethylene film (double-sided black and white) and black row cover (TNT), and the subplots sampling dates of plants of the hybrid tomato Mariana at intervals of fourteen days, from the seedling stage (14, 28, 42, 56, 70, 84 and 98 days after transplanting, DAT). The plants were harvested in the surface area of each plot, partitioned into leaves, stems, flowers clusters and fruit, and placed in an oven with forced circulation at 65 oC, until constant weight is gotten. The characteristics assessed were: dry matter accumulation of leaves, twigs, flower clusters, fruit, total leaf area and leaf area index. Based on the dry mass of leaves, twigs, flower clusters, fruit and total, it was quantified partition of treated tomato grown in different mulching. Mulching treatments affected the growth of tomato plants with black row cover, white polyethylene and bare soil registering the highest mean of total dry matter, leaf area and leaf area index. The maximum leaf area index was obtained at 71 DAT in the treatments with black row cover (2.88), non-covered soil (2.36), white polyethylene (2.21), 77 DAT in silver polyethylene (2.17) and black polyethylene (1.72). At the end of the cycle, the plant has accumulated a mean of 28.30%, 11.98%, 3.92% and 55.82% of dry leaves, twigs, flowers and fruit clusters, respectively.

The use of compatible rootstocks, besides protecting sensive plant risk of soil- borne pathogens, can increase the yield and improve the quality of the fruit. The study aimed evaluated compatibility, yield and fruit quality of rootstocks and seedless watermelon. The experimental design was randomized blocks, with a 2x3 (two varieties of seedless watermelon: Shadow and RWT8154; three type of root system: without rootstock and upon BGCIA229 and BGCIA941, selected for their resistance/tolerance to nematodes and/or Fusarium spp) with four blocks and six plants/plot. The grafting method was approaching. Hipocotyl diameter of seed- lings of ‘Shadow' was similar to BGCIA229, and 'RWT8154' to BGCIA941. Verified a hight compatibility in combinations 'RWT8154' with BGCIA941 and BGCIA229. Through grafting it was found: Higher survival was observed in 'Shadow' grafted on BGCIA229. increased vegetative growth of 'Shadow' and reduction in 'RWT8154'; delayed of the 'RWT8154' female flowering; increase in fresh plant weight; increase in the yield of 'RWT8154', and reduction in 'Shadow'; increased fruit weight in 'Shadow' grafted on BGCIA229 and 'RWT8154' grafted on BGCIA941; increase in 'RWT8154' peel thickness; greatest firmness; increase in bright- ness and color intensity of the 'Shadow' pulp. The titratable acidity of the cultivars increased and that the SS/ TA ratio decreased in the tested combinations. So there is specificity among cultivars and rootstocks. The com- bination 'RWT 8154' grafted on rootstock BGCIA 941 provided higher yield and fruit quality.

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 .

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.

Anthracnose (Colletotrichum gloeosporioides) and dry rot (Phoma caricae-papayae) of papaya (Carica papaya) reduce fruit post-harvest storage life. Therefore, this study evaluated under laboratory conditions the effect of the hydrothermal treatment of fruits on these diseases. Two types of tests were conducted: (1) fruit immersion in hot water (48 ºC) for 10, 15, 20, 25 and 30 min; and, (2) fruit immersion in hot water at 44, 46, 48 and 50 ºC / 20 min. The experiments were conducted in a randomized complete block design with five replications. Two isolates of C. gloeosporioides and one of P. caricae-papayae were tested in papaya fruits of cv. 'Sunrise Solo' and hybrid ‘Tainung 1’. Fruits were washed, wounded (3mm), inoculated (50μL, 106 conidia mL-1), placed in humid chamber (24 h), and then treated. After treatment, fruits were water cooled (13ºC/20 min) and stored (14 days) in cold chamber (13 ºC; 85-100% R.H.). Daily the diameter of lesions was evaluated for two weeks. Variations on time and temperature did not alter fruit firmness (kg cm-2), pH, total soluble solids (o Brix) e tritable acidity (% of citric acid) in comparison to non-treated fruits. However, in one case on ‘Tainung 1’ fruits, tritable acidity was higher at 48 ºC / 20 min. Fruits treated with hot water at 48 ºC / 20-30 min or 48-50 ºC / 20 min presented less fruit rots.

The fall armyworm is a pest that feeds on various botanies species. The objective of this experi- ment was to study the biology of this pest in corn and cassava leaves. Caterpillars were collected in area under cultivation with cassava and maintained on artificial diet for two generations. Under controlled conditions in a climatic chamber (B.O.D) in the laboratory (25 ºC, 60 ± 10% RH and photophase 14 hours) were evaluated daily 50 caterpillars in corn treatments and 50 in cassava, where duration and viability of the larval phase and pupal, weight of pupas were observed after 24 hours, deformation percentage of pupas and adults, longevity, fecundity and total life cycle. The viability of larvae fed on leaves of maize and cassava was 74% and 60%, respectively. The larval period of the insects was shorter in maize 16.89 days (seven instars) and cassava 20.08 days (six instars). The pupal phase lasted 11.42 days in cassava treatment and 10.87 in the maize. The pupal weight of females and males was higher in corn 204.91 mg and 198.97 mg, respectively. The biological cycle varied depending on the ingested food. Adult longevity lasted 9.88 days for insects fed on cassava leaves. Therefore, cassava affected the development of S. frugiperda.

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.

The cowpea bean (Vigna unguiculata (L.) Walp.) is often attacked by defoliator insects. There are a great number of species of these defoliator insects and they cause huge damage to the plants. The most important being: Diabrotica speciosa e Cerotoma arcuata (both Coleóptera), Spodoptera frugiperda, Mocis latipes e Spodoptera cosmioides (both Lepidoptera). Understanding the relationship between the plague infestation and the productivity of the culture is one of the keys to the success of the integrate management of the cowpea bean. Studying the artificial defoliation process in order to simulate similar insect damages to the plants is useful. There are few research studies about the artificial defoliation in the cowpea bean plant. So, this study was developed to determine the level of economical damage inflicted by defoliator insects in cowpea bean plants in the Cultivar BR-17 Gurguéia. The experiments were conducted in the do Departamento de Fitotecnia do Centro de Ciências Agrárias da Universidade Federal do Piauí. The defoliation were in the order of 0%; 25%; 50%; 75% and 100%. The experiment was taken 25 days and 40 days after planting the cowpea bean plants. The production loss threshold of the cowpea bean in local condition in Teresina-PI is R$ 61.00.ha-1, which allows, through regression analysis, the following conclusion: the level of control of defoliator insects during the vegetative state is about 60% of defoliation; while in the reproductive state it is about 47%.