Dipteryx alata Vogel is a tree species widely found in Cerrado, settling preferentially in well drained soils. Studies related to ecophysiology of D. alata may contribute to the decision making about using seedlings of this species in projects aimed at the recovery of degraded areas where seasonal flooding happens. This study aimed to assess the effects of flooding on photosynthetic and antioxidant metabolism and quality of D. alata seedlings cultivated or not under flooding during four assessment periods (0, 20, 40, and 60 days), followed by 100 days after the end of each assessment period (0+100, 20+100, 40+100, and 60+100 days), allowing verifying the potential for post-flooding recovery. Flooded plants showed lower photosynthetic efficiency than non-flooded plants, regardless of the periods of exposure. However, this efficiency was recovered in the post-flooding, with values similar to that of the non-flooded seedlings. Moreover, the damage to FV/FM was evidenced by an increase in the period of exposure to flooding, but recovery was also observed at this stage of the photosynthetic metabolism. Seedling quality decreased under flooding, not varying between periods of exposure, but remained lower although the increase observed in the post-flooding period, with no recovery after flooding. The occurrence of hypertrophied lenticels associated with physiological changes and an efficient antioxidant enzyme system might have contributed to the survival and recovery of these seedlings. Thus, this species is sensitive to flooding stress but capable of adjusting and recovering metabolic characteristics at 100 days after the suspension of the water stress, but with no recovery in seedling quality. Thus, we suggested plasticity under the cultivation condition and determined that the time of 100 days is not enough for the complete resumption of growth.

The use of edible coating has been an alternative to maintain the quality of vegetables and prolong their post-harvest life. This study aims to evaluate bioactive compounds in Spondias tuberosa submitted to different coating formulations based on Chlorella sp. associated with the pomegranate seed oil, to establish the one that best maintains post-harvest quality. The experiment was set in a completely randomized design, in a 5 × 6 factorial scheme, represented by five coating techniques (T1 = control; T2 = 0.5% Chlorella sp.; T3 = 1% Chlorella sp.; T4 = 1.5% Chlorella sp.; T5 = 2% Chlorella sp.), using 0.3% of pomegranate seed oil in coatings, during five evaluation periods (0, 1, 2, 3, 4 and 5 days), stored in BOD incubator at 24 ± 2 °C and 85 ± 5% RH, with three replicates of ten fruits per plot. Chlorella sp. associated with pomegranate seed oil produced a modified atmosphere around the fruit, retarding the ripening process. Coatings preserved the content of ascorbic acid and phenolic compounds. The treatment containing 2.0% of Chlorella sp. associated with pomegranate seed oil provided the best maintenance for fruit quality.

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The salinity in irrigation water is one of the most important causes to decline cultivated plants yield. The H2O2 application has shown efficiency as a stimulator and activator for antioxidative defense system in plants submitted to biotic and abiotic stresses. The objective of this study was to evaluate methods for hydrogen peroxide application as a strategy to minimize the effects of saline stress on melon plants. The experiment was designed in complete randomized blocks and set in 2 × 4 factorial scheme, consisting two levels for irrigation water salinity (S1 = 0.3 and S2 = 2.0 dS m-1) and four methods for hydrogen peroxide application (15 mM), (T1 = no peroxide application, T2= imbibition of seeds, T3 = at sowing, T4 = Foliar spraying), with five repetitions. It was evaluated the following variables at 58 days after transplanting: plant height, stem diameter, number of leaves, number of flowers, shoot dry mass, root dry mass and total dry mass. The results showed that salinity affected the growth, biomass accumulation and plant quality severely, with the highest losses promoted by the electrical conductivity of 2.0 dS m-1.

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