RESUMO -Objetivou-se com este trabalho descrever os períodos de formação de folhas novas, abscisão foliar, inflorescência e maturação dos frutos do pinhão-manso, Jatropha curcas L., bem como, determinar algumas variáveis de produção desta espécie em dois ciclos de cultivo adubada com diferentes fontes de adubação no município de Remígio-PB. Utilizou-se o delineamento em blocos casualizados com cinco tratamentos e quatro repetições. Os tratamentos foram constituídos por diferentes fontes de adubação. Durante os meses de maio de 2007 a novembro de 2009 fez-se avaliações mensais dos eventos fenológicos e de produção do pinhão-manso. Independente do tratamento utilizado, a formação de folhas novas foi observada durante o período chuvoso e a abscisão foliar durante os meses mais frios e os de maior estiagem. A floração, no primeiro ciclo de cultivo, iniciou-se com o fim da estação chuvosa com a utilização do composto orgânico II (F3), já no segundo ciclo, as primeiras inflorescências foram observadas no início da estação chuvosa nas plantas adubadas com composto orgânico I (F2) e esterco de curral (F5). Em todos os tratamentos o tempo verificado entre a emissão das inflorescências até a maturação fisiológicas dos frutos foi de aproximadamente 120 dias. Na primeira colheita, as fontes de adubação não diferiram entre si em nenhuma variável de produção, entretanto, na segunda colheita, além de haver um aumento na produção, o composto orgânico I (F2) e o esterco de curral (F5) foram os que promoveram os melhores resultados.Palavras-chave: Pinhão-manso. Fenologia vegetal. Floração. ABSTRACT -The objective of this work was to describe the periods of new-leaf formation, leaf abscission, the flowering and fuit-maturity of jatropha, Jatropha curcas L., as well as to determine some production variables of this species, in two crop cycles, fertilized with different sources of nutrient, in the municipality of Remígio, in the state of Paraíba. A randomized block design with five treatments and four replications was used. The treatments consisted of different sources of fertilization. During the months of May, 2007 to November, 2009 monthly evaluations of phenological events and the production of jatropha were made. Regardless of the treatment used, formation of new leaves was observed during the rainy season, and leaf abscission during both the colder and dryer months. Flowering in the first crop cycle began with the end of the rainy season, when using the organic compound II (F3), whereas in the second cycle, the first instances of inflorescence were observed at the start of the rainy season in those plants fertilized with the organic compound I (F2) and manure (F5). In all treatments the time verified between the instances of inflorescence and the physiological maturity of the fruit was approximately 120 days. For the first harvest, the sources of fertilizer did not produce any differences for any of the production variables, however, for the second harvest, besides there being an increase in production, the organic compound I ...

The sesame crop is usually avoided in salt-affected areas because of the various effects of saline stress on plants. Besides varying between species, salinity effects are known to vary for genotypes of the same species as well as plant development stages. Thus, through the irrigation of plants with saline water, this study evaluates tolerance to saline stress of new sesame genotypes in different phenological stages. Three experiments were carried out under greenhouse conditions, using the sesame genotypes BRS Seda, LAG-927561 and LAG-26514. Water with different levels of electrical conductivity (ECw = 0.6, 1.6, 2.6, 3.6 and 4.6 dS m −1 ) was used to irrigate plants during germination and initial growth stages, as well as the entire crop cycle. Tolerance to saline stress (3.6 dS m −1 ) during growth and production stages was also studied. Salinity did not affect sesame germination, but seedling growth was hindered from the ECw of 1.6 dS m −1 onwards, and plant height was the most affected growth variable. Seed production is affected by salinity, regardless of the phenological stage in which plants are exposed to salinity. The strains LAG-927561 and LAG-26514 show promising signs in studies on adaptation to saline stress.

Biochar is material produced during a process called pyrolysis. This material can be used as fertilizer to increase the agronomic productivity of low fertility soils. The objective of this study was to evaluate the soil chemical amendments and the macronutrients leaching following biochar application, produced from poultry litter, in Yellow Red Latosol in laboratory experiments. Soil columns (height 20 cm) containing 0; 10; 15; 20; 25 and 30 t ha-1 of biochar with four replications totaled 24 experimental units. For 30 days, water was applied daily to each column, and the leachates were collected and chemically characterized. After this period, soil samples were taken from the 0-10 and 10-20 cm layer depth and chemically characterized. Biochar reduced exchangeable acidity values. Biochar improved soil fertility. Leachates contained increasing EC, K, Na, Ca and Mg, however the concentration of these elements were small in relation to the biochar doses.

R E S U M OObjetivou-se, com este trabalho, avaliar o cultivo de cultivares de alface em sistema hidropônico tipo floating com soluções nutritivas otimizadas pela ferramenta SOLVER, do Microsoft Office Excel. O experimento foi conduzido no Centro de Ciências Agrárias e Ambientais da Universidade Estadual da Paraíba adotando-se o delineamento experimental inteiramente casualizado disposto em esquema fatorial 4 x 3, com três repetições. Os fatores foram 4 soluções nutritivas (S1 = 100% de solução mineral; S2 = 90% de solução mineral + 10% de solução orgânica; S3 = 84% de solução mineral + 16% de solução orgânica e S4 = 78% de solução mineral + 22% de solução orgânica) e 3 cultivares de alface (C1 -Crespa; C2 -Manteiga e C3 -Rubi). Avaliaram-se a altura da planta, o diâmetro caulinar, o número de folhas, o comprimento da raiz, a massa da matéria fresca e a massa da matéria seca da alface. As soluções organominerais promoveram uma resistência maior à variação do pH e substituíram parcialmente a solução mineral. As melhores médias biométricas e de produção ocorreram para as cultivares Crespa e Manteiga e para as soluções mineral, mineral + 10% de solução orgânica e mineral + 22% de solução orgânica. Hydroponic cultivation of lettuce varieties under optimized organominerals nutrient solution with the SOLVER A B S T R A C TThe study aimed to evaluate the cultivation of lettuce varieties in floating type hydroponic system with nutrient solutions optimized by the SOLVER tool of the Microsoft Office Excel. The experiment was conducted at the Center of Environmental and Agricultural Sciences Center of the Paraíba State University, adopting an entirely randomized experimental design arranged in factorial scheme 4 x 3, with three repetitions. The factors were 4 nutritient solutions (S1 = 100% mineral solution; S2 = 90% mineral solution + 10% organic solution; S3 = 84% mineral solution + 16% organic solution and S4 = 78% mineral solution + 22% organic solution) and 3 lettuce varieties (C1 -Crespa; C2 -Monteiga and C3 -Ruby). The plant height, stem diameter, number of leaves, the length of the root, fresh matter weight and the dry matter weight of the lettuce were evaluated. The organominerals solutions promoted a greater resistance to variation of the pH and replaced partially the mineral solution. The best biometric and production means were observed for the Crespa and Monteiga varieties and for the mineral solution, mineral solution + 10% of organic solution and mineral solution + 22% of organic solution. Palavras-chave:Lactuca sativa L. fertilizante otimização

Salinity in soil or water in arid and semi arid regions can severely limit crop production, since the high amount of NaCl contributes to specific ion effects of Cl − , Na + or both, and to antagonistic effects on nutrient elements. Affected by salt stress, most of the cultivated plants do not fully express their growth potential, which lowers their economic value. Crambe (Crambe abyssinica) is an oil plant of the cruciferous family and it is believed that crambe has great potential to figure as raw material for biofuel; however, literature is not abundant about the effects of salinity in crambe production. This work was carried out in order to evaluate the effects on the development and productivity of crambe irrigated with saline waters under greenhouse conditions. Treatments resulted from the combination of two factors: salinity of irrigation water (ECw) in five levels (1.03control, 2.5, 4.0, 5.5, and 7.0 dS•m −1) and two types of salts (NaCl and NaCl + CaCl 2) with three replications, totaling 30 experimental plots. At the end of the experimental period, soil samples from each plot were collected for chemical and salinity of soil saturation extract analyzes. Salt types did not affect plant parameters. However, the salinity levels presented significant effects on the all plant parameters, decreasing their values with the increase of the salt dose. Salinity levels of the solutions used for irrigation in this study affected the growth of plants and grain yield of crambe. Regarding the type of salts, a higher concentration of Na was observed for NaCl solutions at 2.5, 4.0 and 5.5 dS•m −1 salinity levels.