Francisco Irael de Souza’s research while affiliated with Federal Rural University of Semi-Árido and other places

Melon (Cucumis melo L. cv Goldex) was cultivated using different ages of seedlings (0, 6, 8, 10 and 12 days after sowing), soil mulching, nonwoven fabric (TNT) barrier against pests, and without mulching and TNT as control, in the Brazilian semiarid. Then, the postharvest quality of fruits was evaluated. Results showed that 8 or 10-day-old seedlings provided fruit with the highest pulp firmness, soluble solids/titratable acidity ratio and lower transverse length. In its turn, the use of soil mulching and nonwoven fabric provided fruits with higher fresh weight and longitudinal length, and lower pulp firmness than control. Such characteristics are desirable for melon exportation. In conclusion, in addition to protecting plants against pest and weeds and to improving soil conditioning and plant growth, the use of mulching, nonwoven barrier, and older seedlings improved the postharvest quality of melon fruits.

The study aimed to evaluate the bioactive compounds and antioxidant activity of edible fraction (pulp and peel) in green and ripe ripening stages of the fruit and the seed of wild plum (Ximenia americana L.) from different production sites of occurrence in the semiarid region of Brazil. To characterize the edible fraction, the experiment was conducted in a completely randomized design in a factorial 3 x 2, where the first factor was the collection sites and the second factor the maturation stages, with 4 repetitions with 25 fruits each. As for seeds the experiment was conducted in a completely randomized design with 4 repetitions, totaling 25 seeds per experimental plot. The fruits were collected in the communities of Mulunguzinho, Pau Branco and Mata do Meio in the county of Mossoró, RN, Brazil. The edible fraction of the fruit Ximenia americana contains high levels of vitamin C (160,26 mg/100 g), yellow flavonoids (43,12 mg/100 g), total extractable polyphenols (3066,48 mg/100 g) and antioxidant activity (365,55 g fruit/g DPPH e 251,70 μmol Trolox/g) and the seeds contain content of polyphenols (2067,56 mg/100 g) and antioxidant (373,80 g fruit/g DPPH e 279,96 251,70 μmol Trolox/g). The edible part of the green fruit contains higher content of total extractable polyphenols, total carotenoids, yellow flavonoids and total anthocyanins. The edible portion of the fruits and the seeds from the community of Pau Branco contains the lowest content of total extractable polyphenols and antioxidant activity.

This work aimed to evaluate the new postharvest quality of papaya tree hybrids grown in a region of semi-arid climate, aiming to find the most suitable for marketing as new cultivars. It was conducted in a commercial farm in the municipality of Mossoró-RN, an experiment in a randomized block design with 14 treatments (12 hybrids in testing, plus two more cultivars already marketed, Tainung No. 1 and Sunrise Solo), with 4 replications. The fruits were harvested during the second maturation stage (fruit with up to 25% yellow skin) and taken to the Postharvest Laboratory of UFERSA, where they were accommodated at room temperature (22 ± 1°C and 60 ± 5% RH) until they reaches the fifth maturation stage (fully ripe fruit, with 76-100% of yellow skin), and analyzed for their physical, physical-chemical and biochemical traits. There was great variability among hybrids for the evaluated quality characteristics. However, the hybrids showed characteristics such as mass and dimensions of fruits, vitamin C, soluble solids, pulp thickness that fall under the classification for commercialization both in the domestic and international markets, with the exception of the hybrids H36.45, H36.56, and H45.56, which have yellow pulp, which is not favored in the consumer market.

O pepino é uma importante hortaliça amplamente cultivada por pequenos e médios produtores no semiárido do Brasil. O experimento foi desenvolvido com o objetivo de avaliar os efeitos de diferentes soluções nutritivas do pepino cultivados em substrato de fibra de coco sob o crescimento e composição mineral de folhas. O delineamento experimental foi o de blocos casualizados com quatro repetições. A solução nutritiva padrão foi preparada seguindo a recomendação de 100% sugerida por Furlani para a cultura do pepino. A partir dessa recomendação, foram testadas novas concentrações de nutrientes: 12,5; 17; 25; 50 e 100%, que após a diluição dos nutrientes apresentou condutividades de 1,0; 1,2; 1,5; 2,3 e 3,8 dS m-1, respectivamente. A partir dos sete dias após o transplantio foram medidas as variáveis altura de plantas, diâmetro caulinar e número de folhas. No início da floração (30 dias após o transplantio) foram coletadas de cada parcela duas folhas por planta, a partir do broto terminal, para determinação dos teores de macro e micronutrientes na biomassa seca das folhas. As variáveis de crescimento altura de plantas, diâmetro do caule e número de folhas foram influenciadas pela interação proporção de nutrientes na solução nutritiva × idade das plantas. As plantas de pepineiro estavam adequadamente nutridas em nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), cobre (Cu), manganês (Mn), ferro (Fe) e zinco (Zn).

Cucumber is an important horticultural crop widely cultivated for small and medium growers in semiarid regions of the Brazil. In order to evaluate the nutrient solution effect on development and mineral composition of cucumber grown in coconut fiber substrate, an experimental was carried out using completely randomized design with four replications. A standard nutrient solution was prepared following the recommendation of 100% suggested by Furlani for cucumber crop. Concentrations of nutrient solution were to simulate by standard nutrient solution: 12.5, 17, 25; 50 and 100 % (control) and, after the nutrients dilution showed conductivities following: 1.0, 1.2, 1.5, 2.3 and 3.8 dS m-1, respectively. Seven days after transplanting the variables plant height, stem diameter and number of leaves were recording. For each plot two leaves of cucumber terminal shoot was collected at beginning of flowering (30 days after transplanting) and, macro and micronutrients was analyzed in dry biomass. Growth variables plant height, stem diameter and number of leaves were influenced by the interaction ratio of nutrients in the nutrients solution age of the plants. The cucumber plants were adequately nourished in nitrogen, phosphorus, potassium, calcium, magnesium, copper, manganese, iron and zinc.

Ximenia americana popularly known as wild plum grow wildly in Brazilian semiarid region and its fruit were harvested in two maturity stages and evaluated for quality. The experimental design was completely randomized with three treatments (immature, mature pulp and seeds), and treatment effect was evaluated for pulp fraction (composed of both mesocarp and exocarp or peel) in maturation stages: immature (largest size with green colored peel), mature (largest size with yellow colored peel) and seeds of mature fruits, from eight repetitions of 25 fruits each, totaling 200 fruits per treatment. Fruit were separated and evaluated for physical and physicochemical variables, mineral composition, bioactive compounds content and total antioxidant activity (TAA). The X. americana grown in Brazilian semiarid region presents a great potential to further commercial exploitation. The pulp, aside its maturation stage contains high levels of lipids, proteins, sugars, starch, titratable acidity, vitamin C, yellow flavonoids, polyphenols and antioxidant activity. The seed also presents high levels of lipid, protein, starch, total extractable polyphenols and antioxidant activity. Imature pulp stands out for acidity, polyphenol, flavonoid and anthcyanin levels, while mature fruit pulp has higher yield, sugar and vitamin C levels. Seeds have higher starch, protein and lipi levels. The antioxidant activity found for wild plum pulp could be attributed to polyphenol and vitamin C contents; meanwhile, the antioxidant activity of seeds was dependent only on polyphenolic content. Pulp had higher Na, K, Mg, Ca and Fe levels, however, both seed and pulp fractions have substantial contents of P, K, Cu and Mn.