This study had the objective of surveying the occurrence of tubers in native imbu (Spondias tuberosa) trees in the Northeast of Brazil. It was carried out in 36 native trees in the Caatinga area of the communities of Sitio Papagaio (Juazeiro-BA), Saco Farm (Jaguarari-BA) and Alto do Angico (Petrolina-PE), from August 2000 to November 2002. In each community, twelve plants were randomly selected for tuber extraction. The following variables were analyzed: plant height, trunk diameter at soil level, canopy diameter, as well as number and total weight of tubers per tree. In the community of Sitio Papagaio, in average, 978.42 tubers per tree were collected, with a total weight of 1731.2 kg. In the community of Saco Farm, in average, 1011.58 tubers were collected, with a total weight of 1820.13 kg. In the community of Alto do Angico, in average, 731.58 tubers per tree were collected, with a total weight of 1370.09 kg. The occurrence of tubers per tree in the communities was, in average, 907.19, with a total weight of 1352.12 kg per tree.

This work was carried out in order to evaluate the mycorrhizal fungi in four surrounding areas of Parque Estadual da Serra do Mar, in Ubatuba (SP), with the following covering vegetation: banana plantation interposed at forest, cassava plantation, capoeira area and secondary forest. Soil samples were collected in July 2003 and March 2004. Regarding arbuscular mycorrhizal fungi (AMFs), the crop areas of banana and cassava showed higher spore number than forest and capoeira areas in the winter. In the summer, only cassava area showed high spore production. The rainy season provided a higher number of AMFs species compared to the dry season, in both forest and banana areas. However, regarding the occurrence of different AMFs species there was no clear pattern as to wet or dry season.

The insects of the Chrysopidae family are very important for biological pest control. The present work had the objective of determine the consumption capacity of eggs of three moths species by Chrysoperla externa larvae, besides to verify the larvae-adult period viability, duration of the larval period, and the total mass (g) of consumed eggs. The experiment was accomplished in laboratory conditions, under controlled temperature (25 + 2 ºC), UR (75 + 10%) and photoperiod (14:00 H). Insects of the first generation (F1) were used, being three treatments with 30 replications, under DIC. The obtained results showed that the eggs of S. cerealella and A. kuehniella provided higher viability for the larvae-adult period of C. externa; the duration of the larval period of C. externa was smaller when the eggs of A. kuehniella were used as food; and the larvae of C. externa, preferentially consume the eggs of A. kuehniella, being the higher consumption in the third ínstar.

The predatory mite Euseius alatus DeLeon has been reported in several economic crops in Brazil, with certified importance in fruit trees and coffee. In order to establish an integrated pest management program it is important to determine the efficient pesticides in pests control, but presenting low impact to predators. This work had the objective of evaluating the toxicity of acaricides (abamectin, azocyclotin, diafenthiuron, dicofol, sulphur, fenpropathrin, fenpyroximate, propargite, tetradifon) to eggs and adult females of E. alatus. Leaf discs of "feijão de porco" (Canavalia ensiformes L.) containing 10 eggs of E. alatus were immersed into the acaricides dilutions, during five seconds, and dried for 30 minutes under room temperature. Treated eggs were observed up to 72h to determine egg survival. The residual effect of the same acaricides to adult females of E. alatus was studied using arena constituted by treated leaf disc. Ten adult females were confined per arena, 30 minutes, 24h and 72h after immersing the discs into the acaricides dilutions. Mortality was measured 24, 48 and 72h after confining the females on the treated leaf discs. All tested acaricides showed low impact on egg survival, except for fenpropathrin that caused reduction of egg survival at rate of 66%. The acaricides azocyclotin, diafenthiuron, tetradifon and abamectin caused 100% of mortality to adult females. Otherwise, diafenthiuron (500g de a.i./Kg), fenpyroximate (50g de a.i./L), propargite (720g de a.i./L) and tetradifon (80g de a.i./L) caused lower impact to adult females of E. alatus and, therefore, being of potential recommendation into an integrated pest management.

The aim of this work was to examine the effect of different temperatures on germination of the seeds in O. canum. The seeds had been washed in under water and after immersed for 30s in water with environmenttemperature, 25, 30 (control), 50, 75 and 100ºC. After that it was immersed per 5 minutes in fungicidal solution and later washed by 10s with water and placed to germinate in plates of Petri conditioned in germination chamber regulated to provide temperature of 25 ± 1,0ºC and photoperiod of 12 hours. The completely randon design was used in experiment, with 5 treatments and 10 repetitions, resulting in 50 parcels. Each experimental unit wasconstituted of a plate of Petri contends 10 seeds. The averages had been compared by the Scott-Knott test at 5% level of probability. The germination rate was statistically equal in the control and the temperatures of 25, 50 and 75ºC, being superior to that one gotten to 100ºC. The temperature of 30ºC was the one that provided the biggest rate of germination, while that of 100ºC is not indicated for the breaking in dormancy of thisspecies, since it promoted the death of the embryo.

Aiming to evaluate seedling emergence of black sapote (Diospyros ebenaster Retz.) it was developed an experiment with seeds, collected on mature fruits, proceeding from Germoplasm Bank of Horticulture Department, University of São Paulo State, Jaboticabal, Brazil. Immediately after extracted, the seeds were washed, dried in paper and put in plastic box filled with the substrate studied, thus characterizing four treatments, as follows: Plantmaxâ; Coconut fiberâ; Sand; Soil mix [soil + sand + bovine manure (3:3:1)]. It was observed emergence percentage (E%) and rate of emergence speed (RES). The different substrates had statisticalinfluence on variable studied. The highest E% was obtained on soil mix, Plantmaxâ and Coconut fiberâ substrates and the best RES was observed on soil mix and Plantmax? substrates.

This experiment was carried out in the greenhouse of the Departament of Animal Production/ UFRPE, from november of 2002 to may of 2003. The work objective was to evaluate the chemical composition of different Panicum maximum Jacq. cultivars submitted to different levels of nitrogen fertilization. It was used a complete randomized experimental design and the treatments were represented by the factorial arragement of the cultivars Massai, Atlas and Tobiatã and the nitrogen fertilization (0, 80, 160 and 320 kg of N.ha-1.year-1), with four replications. The plants were cut 60 days after-seeding for uniformization and three cuts were carried out with intervals of 35 days and intensity of 10 cm. It was determined concentration of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF). Massai presented lesser crude CP (12,7%) and greater NDF concentration (60,8%) than the other cultivars. There was significant effect of the nitrogen fertilization for the CP and NDF. The increase in the nitrogen level raised the CP concentration and reduced the FDN concentration of the studied plants. The Atlas may be considered the cultivar that presented the best chemical composition because its satisfactory CP concentration (15,3%) associate to the lesser NDF concentration (58,8%).

In agriculture practiced in Brazil, the branch of the horticulture is one of the prominences, in production and in exportation, being melon one of the more produced fruits, especially in Brazil¿s northeast. In this context, the use of a good quality substrate is essential for the development of the plants. In this study it was evaluated the growth of melon seedlings and the role of Arbuscular Mycorrhizal Fungi (AMF),Glomus clarum, associated to the use of coconut dust, as an alternative substrate, at 100, 80, 60, 40, 20, 10 and 0% concentrations, as a soil mixture (grayish Argissol). The plants were cultivated under greenhouse conditions and, at the end of a 35 days period, were analyzed the diameter of the stem, number of leaves, height of plants, shoot dry weight, microbial biomass carbon content, basal soil respiration, metabolic quotient, colonization with AMF and shoot nutrient content (N, P, K, Ca and Mg). It was observed that 100% and 80% concentration of coconut dust were the more restrictive treatments for plant development. Microbial carbon and mycorrhizal colonization were higher when the substrate was composed by 10 and 20% of coconut dust. The basal soil respiration and the metabolic quotient (2,07) were higher when 100% coconut dust was used, while the smallest value (0, 96) was found in treatment without coconut dust. The use of concentrations higher than 40% of coconut dust decreased AMF activity and growth of the melon plants.

The physiologic activity of two corn varieties regarding nitrogen accumulation and remobilization in the vegetative phase was evaluated by the activity of the nitrate reductase enzyme (NR), and NO3 - contents of the N-amino and soluble sugars in leaves, hems and stems of the plants. The varieties were selected according to their agricultural characteristics: BRS 4157 (Sol da Manhã), an improved variety used in familial agriculture and BRS 1010, an exotic variety, a simple hybrid used in extensive agriculture. The plants were cultivated in a greenhouse, in pots containing a Red-Yellow Argissol submitted to two doses of N-NO3 - (130 and 1300 mg of N per pot). Harvests were made at the first two stages of the vegetative development, at 32 and 60 days after germination (DAG). The Sol da Manhã variety, efficient in nitrogen use, adapted itself to the condition of low nitrogen due to its higher capacity in accumulating NO3 - in the leaves in the first development stage, and remobilizing it during the second stage. This resulted in a higher free amino-N concentration in the leaves and hems when compared to the simple hybrid BRS 1010, described as a high potential in productivity under low nitrogen conditions.

Copaifera langsdorfii is a typical tree species very important for restoration of degraded areas. This study evaluated the effect of different temperatures and light conditions on Copaifera seed germination. The applied treatments were the temperatures of 25ºC, 30ºC and 20-30ºC and three different light expositions (constant dark, 8h of light plus 16h of dark and constant light). The tested variables were percentage, velocity and average time of germination. The treatments consisted of 200 seeds, with four replications of 50 seeds each, sown on a Germitest towel paper and maintained for 28 days on germination chamber. The completely randomized design was used and the averages compared by Tukey test at 5% probability. Germination percentage was not influenced by the treatments. The constant temperatures of 25ºC or 30ºC, independently of light regime, promoted a higher rate of germination velocity and caused the reduction of the germination average time.