Este trabalho teve por objetivo avaliar a vida útil de cinco híbridos de melão cv. amarelo (AF-7100, AF-1498, AF-5107, AF-4945 e AF-1805) produzidos no Agropolo Assu-Mossoró-RN. Após atingido o estádio de maturação, os frutos foram colhidos e conduzidos ao Laboratório de Pós-Colheita da Universidade Federal Rural do Semiárido (UFERSA), onde se retiraram ao acaso 12 frutos de cada híbrido para caracterização no tempo zero. Em seguida, os demais frutos foram pesados, identificados e armazenados em câmara refrigerada regulada a 10±1ºC e 90±2% UR, onde permaneceram por 7; 14; 21; 28; 35; 42; 49; 56; 63 e 70 dias. Em cada intervalo de tempo, avaliaram-se nos frutos: perda de massa, firmeza da polpa, aparência externa e interna, pH, acidez titulável, sólidos solúveis, açúcares redutores e açúcares solúveis totais. o delineamento experimental foi o inteiramente casualizado, em esquema de parcelas subdivididas no tempo. Na parcela, está o fator híbridos e, na subparcela, os tempos de armazenamento. Foram utilizadas três repetições, sendo a parcela constituída por três frutos. Houve interação significativa entre híbrido e período de armazenamento para a firmeza de polpa dos frutos. Para as demais características avaliadas, foi observado o efeito dos fatores principais. Durante operíodo de conservação,ohíbridoAF-7100 apresentou maior firmeza dos frutos, seguida da cultivar AF-5107. Houve aumento na perda de massa durante o armazenamento e não se observaram danos nas aparências externas e internas até 42 e 28 dias de armazenamento, respectivamente.

RESUMO -O objetivo deste trabalho foi estudar algumas alterações físicas e químicas durante o desenvolvimento de frutos de melão de quatro cultivares. Para isto foram plantadas quatro cultivares de melão na área experimental do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido -UFERSA, onde foram monitorados os períodos da antese. O delineamento experimental foi em blocos completos casualizados, com três repetições, em esquema de parcela subdividida. As parcelas foram constituídas pelas cultivares de melão ('AF 1749', Hy-Mark, Rochedo e Caipira) e as subparcelas pelas idades dos frutos (14; 21; 28; 35 e 42 dias após a antese). Quatro frutos por subparcela foram colhidos nestas idades e foram analisados quanto à massa média, firmeza, sólidos solúveis, acidez total, vitamina C e pH. Verificou-se interação significativa entre os fatores estudados (idades x cultivares) para massa média dos frutos, firmeza de polpa, acidez total, pH, vitamina C e sólidos solúveis. A massa dos frutos, firmeza, sólidos solúveis, pH e Vitamina C aumentaram, e a acidez diminuiu durante o desenvolvimento dos frutos. Termos para Indexação: Cucumis melo L., qualidade de frutos, idades dos frutos, antese. PHYSICAL AND CHEMICAL CHARACTERIZATION OF MELON FRUITS DURING THEIR DEVELOPMENTABSTRACT -The objective of this work was to study some physical and chemical changes during melon fruits development of four cultivars. An experiment was carried out at the experimental area of Plant Science Department of Universidade Federal Rural do SemiÁrido -UFERSA, where the anthesis period was monitored. The experimental design used was of randomized complete blocks with three replications in a split-plot scheme. To the plots were assigned the melon cultivars ('AF 1749', Hy-Mark, Rochedo e Caipira) and to the subplots were assigned the harvested fruit times (7, 14, 21, 28, 35 and 42 days after anthesis). Four fruits per subplot of each cultivar were harvested in the different fruit times, and then, they were analyzed for average weight, firmness, soluble solids, total acidity, vitamin C and pH. There was a significant interaction between harvested fruit times and cultivars for average fruit weight, pulp firmness, total acidity, pH, vitamin C and soluble solids. The average fruit weight, pulp firmness, soluble solids, pH and Vitamin C increased and the total acidity decreased with the melon fruit's development.

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Deep soil preparation system and its influence on sugarcane development Sugarcane is one of the most important crops in the Brazilian agribusiness chain, besides its great branch in the international context as a renewable and sustainable energy source. Through the competitiveness that sugar mills experience and through the growth perspectives of the sector, this study focuses the deep soil preparation for sugarcane crop renewal, since it provides a larger soil volume to be explored by the root system. Furthermore, the machinery traffic controlled by a smaller number of soil preparation operations, reduces farmer´s production costs. The general objective was, therefore, evaluate soil preparation methods and develop a controlled traffic system in the area, in order to propose to the farmer a cost reduction in the farm soil management along with yield increase and extension of the longevity of the crop. As a result of the imposed treatments it was possible to conclude that by the root length analysis in all depths of the

Ratings of crop behavior under different soil water conditions are very important to improve agricultural management, a difficult task to be carried out in greenhouses due to the lack of simple methodologies of low cost and of easy implementation. This article evaluates the efficiency of using a computational program of Sequential Water Balance, to study the response of the Jatropha curcas crop under different irrigation levels. Pots of large size (1.0 m high and 0.3 m in diameter), difficult to be weighed, were used in a greenhouse, from June to December 2009, in Piracicaba, SP, Brazil, with plants grown in a substrate of 50% sandy soil and 50% cured manure. The experimental design consisted of randomized blocks with treatments corresponding to water depths of 100%, 75% and 50% of the maximum available water capacity (AWC), with 16 replicates. Measuring only air temperature and knowing substrate AWC it was possible to control the soil water conditions over the whole experimental period, which were checked at the end of the experiment. Data indicate that this simple method that avoids weighing heavy containers in large number is very suitable for water control in pots arranged in a greenhouse.