The irrigation with saline water reduces crop growth and yield, resulting in the need of new techniques that enable the use of this natural resource in fruit growing. In this sense, the objective of this study was to evaluate the effect of saline irrigation water associated with different nitrogen doses on guava rootstock cv. Paluma morphophysiology. The experiment was carried out in a completely randomized blocks design, testing 5 electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four nitrogen doses for fertilization (541.1; 773.0; 1004.9 and 1236.8 mg dm-3), in a 5x4 factorial, with four repetitions. The increase in the ECw from 0.3 dS m-1 negatively affected the morphophysiology of guava rootstock cv. Paluma, especially during the younger phase of the crop. The N dose of 541 mg dm-3 stimulated the increase of most morphophysiological variables in guava rootstock during the period studied. The nitrogen fertilization did not reduced the salt stress effect on the evaluated variables.

The effect of coatings with different concentrations of tamarind seed starch associated with pomegranate seed oil in ‘Paluma’ guava was investigated in the present work. The fruits were harvested from an orchard in the morning, packed in containers previously lined with paper, and transported to a laboratory, where they were selected, washed, sanitized, and separated at random for the application of each treatment. The experiment design used was completely randomized, in the 6 × 6 factorial scheme, six coatings and six evaluation periods, with 3 replicates made up of 2 fruits. The treatments were: T1 (control or reference sample), without coating; T2 (0.24 mL of pomegranate seed oil/mL of coating); T3 (2% tamarind starch); T4 (1% tamarind starch); T5 (2% of tamarind starch); T6 (3% tamarind starch), T4, T5 and T6 were associated with 0.24 mL/mL of the pomegranate seed oil. The treatments were applied under immersion of the fruits in the solutions and then stored in a refrigerated chamber at 10±2 °C and 80±5% RH, and the evaluations were performed at intervals of 3 days to 12 days of storage. Due to the maintenance of the quality of the fruits, and without sufficient material, it was decided to extend storage time until the 21 days. Thus, the analyses were performed at 0, 3, 6, 9, 12 and 21 days with evaluations at 0, 3, 6, 9, 12, and 21 days. The T6 treatment (3% tamarind starch + 0.24 mL/mL pomegranate seed oil) was more efficient regarding luminosity (L*) of the fruits and delaying color development , expressed by the values of C*, also showing the higher retention in the loss of firmness, lower mass loss and lower soluble solids content, suggesting that this treatment possibly inhibited the degradation of polysaccharides, delaying the ripening process of the fruits.

It is very challenging to the quality of the papaya culture’s fruits (Carica papaya L.) after the crop, especially due to their significance to the international market, that is, their elevated exportation demands. The purpose of this work was the application of biodegradable coatings composed of Scenedesmus sp. and Chlorella sp. associated or not with pomegranate seed oil in ‘Golden’ papaya and to evaluate their effect in the conservation powder-crop. The installation of the experiment was carried out in a completely randomized design, with a 6 x 6 factorial outline, that is, six concentrations (C: control; SO: 0.5% of Scenedesmus sp. + 0.3% of pomegranate seed oil; S: 0.5% of Scenedesmus sp.; CO: 0.5% of Chlorella sp. + 0.3% of pomegranate seed oil; CH: 0.5% of Chlorella sp.; O: 0.3% of pomegranate seed oil) and six evaluation periods (0, 3, 6, 9, 12, and 15 days), stored at a temperature of 18±2 °C with 60±5% RH with three repetitions of two fruits per portion. The use of coverings composed of Scenedesmus sp. and Chlorella sp. in association or not with pomegranate seed oil was proven efficient in the reduction of the breathing tax of ‘Golden’ papaya, delaying the ripening process, and therefore representing a promising alternative for these fruits’ powder-crop conservation. The coating composed of 0.5% of Chlorella sp. + 0.3% of pomegranate seed oil (CO) provided a better powder-crop conservation of ‘Golden’ papaya during 15 days of storage.

ABSTRACT In semiarid areas, the scarcity of water with low salt concentration associated with irregular precipitation becomes a limiting factor to ensure agricultural production. In this context, the objective of this study was to evaluate the growth and production of sesame genotypes under different strategies of use of saline water. The experiment was conducted under protected environment conditions, using a randomized block design in a 6 x 2 factorial scheme, and the treatments consisted of six strategies for the use of saline water in the different stages of plant development (SE = irrigation with low-salinity water throughout the cultivation cycle; VE, FL, FR, VE/FL and VE/FR - respectively, irrigation with high-salinity water at the vegetative stage, flowering, fruiting, vegetative/flowering and vegetative/fruiting) and two sesame genotypes (BRS Seda and BRS Anahí), with 4 replicates. Irrigation with high-salinity water (ECw = 2.7 dS m-1) during the vegetative, flowering and fruiting stages did not compromise sesame production. There were reductions in sesame growth when irrigation with high-salinity water was continuously applied at the vegetative/flowering stages and in sesame production when it was applied during the vegetative/flowering and vegetative/fruiting stages. The greater growth of BRS Seda sesame plants resulted in an increase in the total number of fruits and in the total seed weight.

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