Pitanga (Eugenia uniflora L.) cultivation has increased rapidly around the world, but most seedlings come from sexual propagation and thus present high genetic variability and respond differently to environmental conditions. This work studied the phenology and thermal requirement of pitanga genotypes in the Brazilian semiarid. Forty‐eight genotypes were evaluated in 2017 and 2018 in an experimental farm at the Federal Rural University of Semiarid, Mossoró, Brazil. The time and thermal requirement for phenological stages from fruit pruning to harvesting, and fruit production were evaluated. Highly productive and precocious genotypes were identified, and six groups were arranged based on dissimilarity.

The initial development of pitayas may be limited by a few factors, among them, water deficit. Agricultural hydrogels can be used as an alternative to enhance the retention and availability of water and nutrients in the soil. Therefore, this study aimed to evaluate the influence of irrigation frequency and hydrogel doses on the development of white pitaya (Hylocereus undatus) seedlings to establish a time interval in days between irrigations that provides better seedling development and determine the hydrogel dose that provides a reduction of water consumption without damaging seedling development. The experimental design consisted of randomized blocks in a 4 x 4 factorial arrangement, in which the treatments corresponded to 4 hydrogel doses (0, 2, 4, and 6 g/plant of Biogel Hidro Plus) incorporated into the substrate and four irrigation frequencies (1, 3, 5, and 7 days of interval). The biometric characteristics, photosynthetic pigments, and organic and inorganic solutes of the plants were evaluated after 120 days. The use of daily irrigation negatively influenced the growth and biomass accumulation of the aerial part of the seedlings and, consequently, provided the lowest values of cladodes of the pitaya seedlings. Pitaya seedlings had greater development when using an irrigation frequency of around 3 days. The application of 6 g/plant of hydrogel provided the highest averages for accumulation of dry biomass, photosynthetic pigments, and organic and inorganic solutes at irrigation levels of 3.6, 4, and about 3.8 days of intervals, respectively. Hydrogel incorporation allowed increasing the interval between irrigations by 1 day without damages to the seedling development.

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The need to diversify agricultural production has fostered the cultivation of several crops under environmental conditions atypical to their origin, justifying the extreme importance of studies on the agricultural management of crops in semiarid regions. In this context, this study aimed to evaluate the effects of irrigation depth and potassium doses on fig quality under semiarid conditions. The experiment was conducted in a 4 × 4 split-split-plot design, in randomized block design, with three replicates. The plots corresponded to four irrigation levels (50%, 75%, 100%, and 125% ETc), the subplots consisted of four potassium doses (0, 60, 120, and 240 g K2O plant−1), and the sub-subplot corresponded to the crop years (2018/19 and 2019/20). Results showed that water deficit reduced fig productivity, and the irrigation levels equal to or greater than 100% ETc performed cumulatively throughout the growing cycles. Therefore, irrigation depths from 85.19% to 95.16% ETc are recommended for greater water-use efficiency and fruit quality. Furthermore, potassium fertilization mitigated water stress in fig plants, allowing for reduced irrigation levels, especially in the second year, without compromising fruit traits.

A fenologia pode ser definida como o estudo dos eventos periódicos da vida da planta em função da sua reação às condições do ambiente, e sua importância está relacionada ao manejo que pode ser desenvolvido para as culturas em função desses resultados. Com o objetivo de avaliar a fenologia do coqueiro, um experimento foi conduzido no pomar didático da Universidade Federal Rural do Semi-Árido-UFERSA. A área experimental foi composta por coqueiros da variedade anão verde com quatro anos de idade, propagadas via sementes e plantadas no espaçamento de 7,5 m x 7,5 m, irrigadas por microaspersão. Foram selecionadas, aleatoriamente, quarenta plantas, para as quais foram realizadas as observações fenológicas semanalmente, durante o período de janeiro a outubro de 2015. Foram analisadas as seguintes variáveis: altura da planta, comprimento e diâmetro do estipe, comprimento da folha n° 14, emissão do 2º, 3° e 4° cacho, número de folhas vivas, número de inflorescências totais por planta, número médio de frutos com 5, 6, 7 e 8 meses de idade, número de frutos totais e porcentagem de abortamento de frutos do cacho com 5, 6, 7 e 8 meses de idade. Os caracteres vegetativos e reprodutivos são influenciados pela idade da planta, assim como pelas condições climáticas.