Photo-selective shading screens are emerging practices that aim to combine crop physical protection with different solar radiation filtration to achieve desired physiological responses. The objective of the present study was to evaluate the effect of photo-selective shading screens on the growth and physiology of purple lettuce for two transplanting seasons in tropical climate in Brazil. A 2 × 4 factorial arrangement was used, being considered the first factor, the transplanting season (spring and fall), and the second factor is the three 35% shading photo-selective shading screens (red, black and silver) and full sun control. The experimental design was a randomized complete block with four replications. The variables studied were: total fresh matter, total dry matter, leaf number, stem diameter, stem length, leaf area, SPAD chlorophyll index, nitrogen balance indexes, chlorophyll, flavonoids and anthocyanins. The photo-selective shading screens influenced the microclimate and the growth variables of purple lettuce, mainly when these plants were sown in the fall. Planting lettuce during spring may result in lower yields due to the higher investment of plants in secondary metabolites to defend against abiotic stress. According to the results, photo-selective shading screens are an appropriate agronomic technique to reduce phenolic compounds and improve lettuce cultivation conditions and can be implemented within protected cultivation practices to improve crop performance.

A recuperação de ecossistemas que já foram degradados podem não ocorrer da maneira desejada se houver carência nutricional ou suprimento insuficiente de nutrientes durante o estádio inicial de desenvolvimento, sendo, portanto, a matéria orgânica um dos meios de grande influência nesta etapa inicial. O objetivo desse trabalho foi avaliar o desenvolvimento e a qualidade de mudas de aroeira em função de substratos contendo diferentes fontes de matéria orgânica. O experimento foi realizado em casa de vegetação localizada no IFES Campus Itapina utilizando-se o delineamento de blocos casualizados com sete tratamentos, sendo eles compostos com diferentes fontes de matéria orgânica (lodo de curtume, resíduo de torrefação de café, esterco bovino curtido, resíduo de laticínio e composto de lixo urbano), sempre na mesma proporção de 20%, além dos tratamentos sem uso de matéria orgânica (terra pura com e sem adubação). Foram avaliadas características de desenvolvimento e de qualidade das mudas, observando-se que todas as fontes de matéria orgânica utilizadas favoreceram o desenvolvimento das mudas de aroeira em relação às mudas que não receberam as dosagens de matéria orgânica. A mistura terra com composto urbano e esterco bovino mostrou-se superior na maioria das características avaliadas gerando mudas de melhor qualidade.

Crop models are crucial in assessing the reliability and sustainability of soil water conservation practices. The AquaCrop model was tested and validated for maize productivity under the selected climate smart agriculture (CSA) practices in the rainfed production systems. The model was validated using final biomass (B) and grain yield (GY) data from field experiments involving seven CSA practices (halfmoon pits, 2 cm thick mulch, 4 cm thick mulch, 6 cm thick mulch, 20 cm deep permanent planting basins (PPB), and 30 cm deep) and the control (conventional practice) where no CSA was applied. Statistics for coefficient of determination (R²), Percent bias (Pbias), and Nash–Sutcliffe (E) for B and GY indicate that the AquaCrop model was robust to predict crop yield and biomass as illustrated by the value of R² > 0.80, Pbias −1.52–1.25% and E > 0.68 for all the CSA practices studied. The relative changes between the actual and simulated water use efficiency (WUE) of grain yield was observed in most of the CSA practices. However, measured WUE was seemingly better in the 2 cm thick mulch, indicating a potential for water saving and yield improvement. Therefore, the AquaCrop model is recommended as a reliable tool for assessing the effectiveness of the selected CSA practices for sustainable and improved maize production; although, the limitations in severely low soil moisture conditions and water stressed environments should be further investigated considering variations in agroecological zones.

Chrysanthemum is one of the most beautiful flowers and probably the oldest plant grown commercially in different parts of the world. Chrysanthemum, like all other plants, is susceptible to attack by various pests and diseases. The use of silicon has been shown to minimize damage caused by insect and also increase shelf life. Thus, the objective of this work was to evaluate the effect of potassium silicate in pest resistance and postharvest longevity of chrysanthemum. The experiment was carried out in the experimental area of the Federal Institute of Education, Science and Technology of Espírito Santo - Itapina Campus, the treatments consisted of four doses of potassium silicate - Sifol® (2, 4, 6 and 8 mL L⁻¹) and a control treatment without foliar application of potassium silicate applied to chrysanthemum cv. Zembla. Leaf application of potassium silicate reduced the incidence of cercosporiosis and thrips in chrysanthemum leaves. Chrysanthemum leaf and flower longevity increased when potassium silicate doses were applied. It is recommended for chrysanthemum cv. Zembla applications of 0.6 and 0.8 mL L⁻¹ potassium silicate.

The objective of this study was to evaluate the capacity to stabilize substrate with tannery sludge and soil in the development and physiology of Conilon coffee seedlings. The treatments consisted of fixed doses of tannery sludge (30% of volume) and different proportions of humus in the substrate (10, 20, 30, 40% and of humus), in addition to treatments with and without conventional soil fertilizer. The biometric and physiological evaluations were measured 210 days after planting the cuttings. Humus allowed the substrate to stabilize, causing the coffee seedlings to develop well, when compared to the conventional substrate, especially in the proportion of 30% of humus, with a higher Dickson quality index in coffee seedlings. Regarding the physiological aspects, there were no changes in the secondary compound indexes or in the nitrogen balance and leaf chlorophyll. Also, there was no damage to the photosynthetic apparatus evaluated by the quantum efficiency of Photosystem II. Treatment 6 composed of 100% of soil, presented the lowest mean of net photosynthetic rate, due to stomatal effects.