Precipitação esperada, em diferentes níveis de probabilidade, na região de Juazeiro, BA

Os eventos de chuvas são preponderantes para o desenvolvimento dos cultivos agrícolas totalmente dependentes de sua ocorrência. Tendo em vista que previsões climáticas nem sempre são precisas, técnicas que possam auxiliar nas previsões, como estimativas de precipitações, com base em níveis de probabilidade de sua ocorrência, podem ser uma boa alternativa. Objetivou-se, neste trabalho, determinar a precipitação pluviométrica esperada, em diferentes níveis de probabilidade, para a região de Juazeiro, BA bem como a época de menor risco de perdas na colheita de uvas finas por causa da ocorrência de chuvas. O estudo foi realizado com dados dos registros pluviométricos diários de uma série de 40 anos, obtidos junto à estação Agrometeorológica de Mandacaru no município de Juazeiro, BA. As estimativas mensais da precipitação pluviométrica provável para os níveis de 90; 80; 75; 60; 50; 45; 40; 35 e 30% de probabilidade foram obtidas pela função de distribuição gama. Aplicou-se o teste de aderência de Kolmogorov-Smirnov, ao nível de 5% de significância para verificar o ajuste dos dados. A distribuição gama apresentou bom ajuste para estimar a precipitação provável em diferentes níveis de probabilidade na região de Juazeiro, BA. Os valores médios de precipitação pluvial mensal ocorreram próximo ao nível de 40% de probabilidade. A época mais adequada para o cultivo de sequeiro na região foi o bimestre fevereiro e março. As menores probabilidades de ocorrência de chuva de maio a outubro proporciona menor risco de perdas na colheita de uvas finas em cultivo irrigado, na região de Juazeiro, BA

Irrigation management methods for the production of bell pepper in agricultural substrates

ABSTRACT This study’s objective was to assess the response and effectiveness of irrigation management systems for the production of bell pepper with different agricultural substrates, under protected conditions. The current study was conducted in a greenhouse located in Juazeiro, BA, in the northwest of Brazil. The experiment design was completely randomized in a split-plot system, with two irrigation treatments as the main plots (the drainage lysimeter and the Piché evaporimeter) and two substrates in each sub-plot (coconut fiber and pinus bark), with 5 replications per treatment. Harvest was conducted from 86 to 151 days after transplanting, and the following characteristics were evaluated: total, marketable and unmarketable yields, production per plant, fresh mass of fruits, fruit number per plant, length and diameter of fruits, length/diameter ratio, water use efficiency, pulp thickness, fruit pH, soluble solids, and titratable acidity. No interaction effects between irrigation treatments and substrates were observed on the following variables: total yield, marketable yield, non-marketable yield, production per plant, mean mass, and diameter of marketable fruits. Irrigation treatments and substrates did not show a significant effect on bell pepper yield. Drainage lysimeter-based management and coconut fiber substrate had the best results in terms of the physical quality of fruits, whereas pinus bark-based substrate positively influenced all chemical variables and the Piché evaporimeter-based irrigation management showed a good performance raising fruit pH in relation to fruits cultivated in lysimeter with pinus bark. Additional research is required under different environmental conditions so that this crop fully expresses its yield potential

Influence of Plastic Covering on the Microclimate in Vineyards in the São Francisco River Valley Region

Abstract Data from field experiments conducted in table grape vineyards variety of Festival in Petrolina-PE in the period from September 19 to October 12, 2010 were used to evaluate the influence of plastic cover on microclimate conditions of vineyards in São Francisco River Valley region. Three treatments were studied: canopies without plastic cover (WC); with plastic cover positioned at 50 cm (PC50), and at 100 cm (PC100) above canopy. The results indicate that the plastic cover prevented the passage of about 40% of the global and net radiation, retained the relative humidity inside the canopy, generated an increase of air temperature and marked reduction in wind speed over the canopy of treatment PC50. However, treatment PC100 had a higher incidence of short wavelength and net radiation under canopy (on the berries) than WC and PC50 treatments, resulting in more favorable weather conditions, providing about 40% greater productivity in this treatment. Therefore, the vineyard with plastic cover placed at 100 cm above canopy represents a more suitable alternative to the climatic conditions of the region of the São Francisco River Valley

Crescimento e produção de Helicônia sob diferentes condições de luminosidade

The use of shading screens of different colors can change the spectral quality of radiation and, as a consequence, the growth and production of crop plants. The aim of this study was to evaluate aspects of the growth, yield, and quality of floral stems of Heliconia psittacorum × H. spathocircinata ‘Golden Torch’ grown under different light conditions. The treatments consisted of four conditions: blue photoconversion screens (35%-40%); red photoconversion screens (18%-21%); black shading screens (45%-49%), and full sunlight. The experiment consisted of two parts. In the first, growth was assessed, whereas in the second, aspects related to the production and quality of floral stems were examined. The experimental design was in randomized blocks with split plots in time. Each plot contained six blocks, with 11 replications per block, giving a total of 66 pots per plot. The evaluations were performed at 30-day intervals over a 6-month period. In the analysis of growth, red screens contributed to the growth of the plants, increasing the number of shoots and leaves, and also plant height. The productivity and quality of floral stems was, however, highest in plants grown under blue and black screens. It can be concluded that, under the prevailing experimental conditions, the use of blue screens (35%-40%) and black screens (45%-49%) is suitable for production of the floral stems of ‘Golden Torch’ heliconia.O uso de malhas de sombreamento de diferentes cores pode alterar a qualidade espectral da radiação e, como consequência, o crescimento e a produção de uma cultura vegetal. Desta forma, o objetivo do presente trabalho foi avaliar aspectos do crescimento, produção e qualidade das hastes florais de Heliconia psittacorum x H. spathocircinata ‘Golden Torch’ cultivadas sob diferentes condições de luminosidade. Os tratamentos consistiram em quatro ambientes: malha fotoconversora azul (35-40%); malha fotoconversora vermelha (18-21%); malha de sombreamento preta (45-49%) e pleno sol. O experimento constou de duas partes: na primeira realizaram-se avaliações de crescimento e na segunda, foram estudados aspectos relacionados à produção e qualidade das hastes florais. O delineamento experimental foi em blocos casualizados em esquema de parcelas subdivididas no tempo, sendo seis blocos por parcela, cada bloco com onze repetições, totalizando sessenta e seis vasos por parcela. As avaliações foram realizadas durante seis meses, com intervalos de trinta dias. Nas análises de crescimento observou-se que a malha vermelha contribuiu com o crescimento das plantas, incrementando o número de perfilhos, folhas e altura das plantas. A produtividade e a qualidade das hastes florais foi superior em plantas cultivadas sob tela azul e preta. Conclui-se que, nas condições experimentais estabelecidas, o uso das malhas azul (35-40%) e preta (45-49%) é indicado para a produção de hastes florais de Heliconia ‘Golden Torch’

Emergence and Structural Characteristic of the <i>Solanum pimpinellifolium</i> in Trays under Different Levels and Types of Substrates

The cultivated tomato is one of the most consumed vegetables in the world, and the preparation of seedlings plays a fundamental role in the success of the crop, which is often plagued by fungi and bacteria from its earliest stages. This study aimed to analyze the emergence speed index and morphological parameters of Wanda hybrid cherry tomato seedlings (Solanum lycopersicum var. pimpinellifolium) in trays with two different types and levels of substrates in a protected environment using certified seeds. The experiment was conducted in the greenhouse of the IFCE—Campus Crato during the months of August and September 2022. Two basic substrates were used to promote germination and emergence: one was the commercial Vivato Slim Plus®, and the other was based on worm humus produced in Minhobuckets kits. The experimental design was completely randomized, consisting of five doses of commercial substrate (SBC) and earthworm humus (HDM) in the following proportions: S1—HDM; S2—SBC; S3—HDM + SBC (1:1), S4—HDM + SBC (1:3), and S5—HDM + SBC (3:1). The ESI, morphological parameters (SD, PH, ROOTL, and NL), and the dry biomass of the seedlings (LDB, SDB, RDB, and TDB) were determined. Data were subjected to an analysis of variance, and Tukey’s test (0.05) was used; dry biomass data were submitted to square root transformation. For the emergence speed index, SBC (S2) outperformed the others. Regarding the morphological parameters and dry biomass, all substrates yielded satisfactory results, despite not showing a statistical difference between the averages. The substrate S4 produced the best results in all evaluated parameters