Methods for overcoming dormancy in Dinizia excelsa Ducke seeds

The impermeability of seed coat to water is common mechanism in Fabaceae seeds. Treatments to overcome hardseededness include scarification with sulphuric acid, scarification on abrasive surface and soaking in water among others. The objective of this study was to identify an effective method to overcome dormancy in Dinizia excelsa seeds. A pre-test (untreated seed) and three experiments were carried out: immersion of seeds in acid sulphuric for 10, 20, 30, 40, 50 and 60min (experiment 1); scarification on abrasive surface at the positions distal end, near of the mycrophyle and on the lateral tissue and tegument clipping at 1mm of the distal end, near of the mycrophyle and on the lateral tissue (experiment 2); scarification on abrasive surface and immersion in water for 0, 12, 24 and 48h (experiment 3). The experimental design was completely with four replications of 50 seeds for each treatment. The statistical analysis was carried out by ANOVA and regression analysis. Seedlings emergence on untreated seeds started on the 8th day after sowing and reached 52.5% on the 1,709th day. In general, the treatments to overcome dormancy increase emergence. Emergence was higher for seeds treated with sulphuric acid for 20 and 30min with emergence of 93.6% and 86.6%, respectively. For seeds scarified on abrasive surface higher emergences were recorded for scarification on distal end, near of the mycrophyle and on the lateral, 82.7%, 74.3% and 75.7%, respectively. Seeds scarified manually showed higher emergence when not immersed in water (75%), or when immersed for 12 and 24h (75%, 73.6% and 65.6%, respectively). Immersion seeds in sulphuric acid for 20 and 30min and scarification on abrasive surface of distal end are effective to overcome dormancy in D. excelsa.

Lime and fertilizer recommendation system for coconut trees

Fertilizer recommendation to most agricultural crops is based on response curves. Such curves are constructed from field experimental data, obtained for a particular condition and may not be reliable to be applied to other regions. The aim of this study was to develop a Lime and Fertilizer Recommendation System for Coconut Crop based on the nutritional balance. The System considers the expected productivity and plant nutrient use efficiency to estimate nutrient demand, and effective rooting layer, soil nutrient availability, as well as any other nutrient input to estimate the nutrient supply. Comparing the nutrient demand with the nutrient supply the System defines the nutrient balance. If the balance for a given nutrient is negative, lime and, or, fertilization is recommended. On the other hand, if the balance is positive, no lime or fertilizer is needed. For coconut trees, the fertilization regime is divided in three stages: fertilization at the planting spot, band fertilization and fertilization at the production phase. The data set for the development of the System for coconut trees was obtained from the literature. The recommendations generated by the System were compared to those derived from recommendation tables used for coconut crop in Brazil. The main differences between the two procedures were for the P rate applied in the planting hole, which was higher in the proposed System because the tables do not pay heed to the pit volume, whereas the N and K rates were lower. The crop demand for K is very high, and the rates recommended by the System are superior to the table recommendations for the formation and initial production stage. The fertilizer recommendations by the System are higher for the phase of coconut tree growth as compared to the production phase, because greater amount of biomass is produced in the first phase.

Using different satellite imagery and classification techniques to assess the contribution of trees outside forests in the municipality of Maringá, Brazil

Forest cover of the Maringá municipality, located in northern Parana State, was mapped in this study. Mapping was carried out by using high-resolution HRC sensor imagery and medium resolution CCD sensor imagery from the CBERS satellite. Images were georeferenced and forest vegetation patches (TOFs - trees outside forests) were classified using two methods of digital classification: reflectance-based or the digital number of each pixel, and object-oriented. The areas of each polygon were calculated, which allowed each polygon to be segregated into size classes. Thematic maps were built from the resulting polygon size classes and summary statistics generated from each size class for each area. It was found that most forest fragments in Maringá were smaller than 500 m². There was also a difference of 58.44% in the amount of vegetation between the high-resolution imagery and medium resolution imagery due to the distinct spatial resolution of the sensors. It was concluded that high-resolution geotechnology is essential to provide reliable information on urban greens and forest cover under highly human-perturbed landscapes.

COLONIZATION OF PALM TREES BY Rhodnius neglectus AND HOUSEHOLD AND INVASION IN AN URBAN AREA, ARAÇATUBA, SÃO PAULO STATE, BRAZIL

The objective of this study is to report on the colonization of palm trees by Rhodnius neglectus, its invasion in an urban area, in Araçatuba - São Paulo, and the control and surveillance measures that have been put in place. Domiciliary triatomine searches occurred in apartments upon the inhabitants' notification. The collected insects were identified and examined for natural infection and food sources with a precipitin test. To search the palm trees, tarps were used to cover the floor, and a “Munck” truck equipped with a tree-pruning device was utilized. Chemical control was performed with the utilization of a manual compression. In 2009, 81 specimens of Rhodnius neglectus were collected from the domiciles by the population. The precipitin test revealed a presence of human blood in 2.7% of the samples. Entomological studies were carried out in these domiciles and in those located within a radius of 200 meters. The search performed in the palm trees resulted in the capture of 882 specimens of triatomines, negative for tripanosomatids. Mechanical and chemical controls were carried out. New searches conducted in the palm trees in the same year resulted in the capture of six specimens. The mechanical and chemical controls of the palm trees, together with the population's work, proved to be effective, therefore preventing these insects' colonization of the city's domiciles.

Wood specific gravity of trees and forest types in the southern Peruvian Amazon

Estimates of terrestrial biomass depend critically on reliable information about the specific gravity of the wood of forest trees. The study reported on here was carried out in the southern Peruvian Amazon and involved collection of wood samples from trees (70 spp.) in intact forest stands. Results demonstrate the high degree of variability in specific gravity (ovendry weight/green volume) in trees at single locations. Three forest types (swamp, high terrace forest with alluvial soil, and sandy-soil forest) had values close to the average reported for tropical forest woods (.69). Two early successional forest types, which make up as much as 12% of the total vegetated area in this part of the Amazon, had values significantly lower (.40). An increase in specific gravity with increasing age of the tree, which has been reported in some spe cies of tropical-forest woods, is seen in a positive relationship between specific gravity and di ameter for a species prevalent in one plot. Increases in specific gravity with tree and forest age may be significant in estimating changes in carbon stores over time.

Dry matter production and nutrient exportation by pruned leaves and branches of apple trees

A trial was conducted on Latossol Vermelho Escuro Orto (Orthox) at Buri, State of São Paulo, Brazil. The material was collected from 'Ohio Beauty¹ and 'Brasil¹ apples trees grafted on 'Doucin'; the trees were 3-4, 4-5 and 6-7 years old. The authors concluded that at the dormant period differen ces were observed on the dry matter production as well on the nutrients exported by the leaves and branches of the two varieties. Branches exported higher amounts of P, Ca, B, Cu and Zn. Larger quantities of N, P and Mn were exported by the 1 eaves.