Biochemical characterization of olive oil samples obtained from fruit mixtures and from oil blends of four cultivars grown in Central Tunisia

Blends of olive oils obtained from four cultivars (Olea europaea L. cv. Chemlali, Chetoui, Oueslati and Koroneiki) were produced by two different methods of blending: processing fruit mixtures or mixing monovarietal oils, using the same proportions of selected cultivars. The obtained blends were biochemically characterized to evaluate quality, and the two methods were compared. The results indicated that the most successful formulations are mainly F8 (60% Chemlali × 20% Oueslati × 20% Koroneiki) characterized by the highest contents of phenols and an elevated oxidative stability, and F5 (50% Chemlali × 50% Koroneiki) containing the highest MUFA level and the highest oxidative stability. The effect of the blending process on pigments and volatiles cannot be easily regulated, unlike phenols, fatty acid composition and OS, all of which positively correlated to the fruit mass ratio in the blend. Results suggest that processing fruit mixtures of different cultivars resulted in a better oil quality than that of oils obtained by the common oil blending method. This blending procedure offers a possibility to modulate the contents of antioxidants, fatty acids and volatile compounds in virgin olive oil, and therefore, its quality and sensorial characteristics.

Effect of condit soil improver on growth, yield and leaf mineral content of two summer pear cvs. with interstocks

The study involving 2 pear cultivars was conducted in 2006–2016. ‘Radana’ and ‘Clapp’s Favourite’ were planted in the spring 2006 in the Experimental Station next to Wrocław (south-western Poland) on Quince S1 and Caucasian pear seedlings with 2 interstocks – ‘Doyenne du Comice’ and ‘Pyrodwarf’. An annual dose of 3 tonnes per hectare of Condit Basic bio-fertilizer was applied onto the tree row soil surface at the beginning of March 2012, i.e., starting from the 7th year after the planting. The study objective was to evaluate effect of Condit preparation on summer pear tree cultivars which are not compatible with Quince, and to assess interstock suitability in their context. The yields obtained in the first eleven years following tree planting were the most abundant for ‘Radana’ on Caucasian pear and on Quince with ‘Doyenne du Comice’ interstock. When applied for 5 years, Condit increased the leaf surface area, however a significant difference was exhibited only by ‘Radana’ on the Caucasian pear. This soil improver did not affect tree growth and yielding; total chlorophyll content; foliar Mg, P, Ca, and K; and mean fruit mass across the investigated treatment combinations.

Flower-visiting insects to Coffea arabica flower at different temperatures and the production of the fruit of arabica coffee

Temperature change may affect insect activity, including flower-visiting insects. Flower-visiting insects, particularly pollinators, have an impact on the fruits produced. This research aimed to study the relationships of flower-visiting insects at different temperatures and coffee production. The gauze experiment was carried out on the coffee plantation that consists of two sites, shaded and unshaded. The study involved 30 arabica inflorescences. The number of flower-visiting insects was recorded and captured. The results showed that the diversity of flower-visiting insects was related to the temperature differences. The flower-visiting insect on the unshaded site was more diverse than the shaded site. The formation of peaberries and the productivity of coffee fruit were also different. Peaberry production was lower (6.24 %) while the fruit mass was heavier (0.15±0.096 g/cherry) in unshaded than shaded sites. However, at the unshaded, the percentage of coffee beans defect was 0.56 % greater than the shaded one. According to these findings, more flower-visiting insects lead to the lower peaberry formation, the heavier fruit mass but potentially causing higher defective coffee beans. The increase in temperature due to climate change can be detrimental because these phenomena will increase the number of coffee fruit defects and insect pests.

Cultivars performance and blackberry pruning management

There was increased fruit consumption with potential health benefits in the last years, being blackberry one of these fruits. The objective of this work was to evaluate the performance of Blackberry cultivars and the influence of main stem management on BRS-Tupy cultivar. The first experiment assessed the cultivars: BRS-Tupy, Cherokee, Xavante, and Guarani; in the second experiment the evaluated prunings were: drastic winter pruning, 2, 3, and 4 main primocanes. The variables analyzed were: green and dry leaf mass, leaf area, number and average fruit mass, production per plant, average size and percentage of fruit moisture, and soluble solids. In relation to average weight, fruit size and yield, BRS-Tupy cultivar was superior in both cycles evaluated. As for soluble solids the Cherokee cultivar was superior, but only in the 2016/17 cycle. In the second experiment, in terms of number of fruits and production, pruning of 4 primocanes in the 2016/17 cycle was superior, but in the next cycle the pruning of 3 primocanes equaled it in the production variable. The drastic pruning in these variables is shown to be lower in the two cycles evaluated. Concerning the variable size of fruit, a significant difference was found only in the 2017/18 cycle, where drastic pruning presented smaller fruits. Thus, it can be concluded that, in general, BRS-Tupy cultivar presents the best productive results and that pruning with 4 primocanes initially stands out alone.

The Transcriptome and Metabolome Reveal Stress Responses in Sulfur-Fumigated Cucumber (Cucumis sativus L.)

Sulfur (S) fumigation is a commonly used sterilization method in horticultural facilities against fungal diseases. S fumigation damaged cucumber leaves, although the response mechanism is unclear. This study analyzes the growth, transcriptome, and metabolomic profiles of young and mature leaves, ovaries, and commercial cucumber fruits to decipher the mechanism of cucumber stress response under S fumigation. S fumigation significantly changed the photosynthetic efficiency and reactive oxygen species (ROS) in leaves, but not fruit development, fruit mass, and peel color. Transcriptome analysis indicated that S fumigation strongly regulated stress defense genes. The weighted gene co-expression network analysis revealed that S fumigation regulated ASPG1, AMC1 defense genes, LECRK3, and PERK1 protein kinase. The abscisic acid (ABA)-mediated model of regulation under S fumigation was constructed. Metabolome analysis showed that S fumigation significantly upregulated or downregulated the contents of amino acids, organic acids, sugars, glycosides, and lipids (VIP > 1 and P-value < 0.05). The opposite Pearson’s correlations of these differential metabolites implied that cucumber had different metabolic patterns in short-term and long-term S fumigation. Besides, the elevated levels of proline and triglyceride indicated that stress-responsive mechanisms existed in S-fumigated cucumber. Moreover, the comprehensive analysis indicated that S fumigation elevated secondary S-containing metabolites but decreased sulfate absorption and transportation in cucumber. Overall, our results provided a comprehensive assessment of S fumigation on cucumber, which laid the theoretical foundation for S fumigation in protected cultivation.

Productivity and quality of watermelon fruits as a function of doses potassium in the Western Amazon

Potassium is the nutrient most demanded by watermelon, performing various physiological and biochemical functions, and its availability in the soil influences the production and quality of fruits. However, there is no recommendation for specific fertilization for the state of Rondônia, which has limited the production and quality of the harvested fruits. The objective of this work was to evaluate the effects of potassium doses on the productivity and quality of watermelon fruits, cultivar Crimson Sweet, in southern Western Amazonia. The experiment was carried out at the Federal University of Rondônia, in the municipality of Rolim de Moura, in an experimental design in randomized blocks, with five treatments and four replications. The treatments were doses 0 (control), 50, 100, 150 and 200 kg ha-1 of K2O. The variables analyzed were fruit mass, longitudinal and transverse diameter of fruits, number of fruits per plant, soluble solids content, exocarp thickness and productivity. Potassium doses did not influence the mean mass and longitudinal and transverse diameter of the fruits. The number of fruits per plant increased linearly as a function of the potassium doses applied, and with 157 kg ha‑1 of K2O the highest values of °Brix were obtained. The dose of 147.2 kg ha-1 of K2O promotes yields 61.6% above the national average and 82% above the state average.

Fruit quality of wild, sweet and yellow passion fruit genotypes in Distrito Federal, Brazil

Despite the importance of passion fruit for the Brazilian fruit market, there are still many agronomic and fruit quality problems to be solved, in order to increase this crop performance. The objective of this study was to evaluate the quality of twelve genotypes of wild, sweet and yellow passion fruit, aiming to identify promising materials considering fruit quality, in Federal District, Brazil. An experiment was carried out at the Água Limpa Farm of the Universidade de Brasília (UnB) from 2016 to 2018, in a randomized block design, with 12 treatments, 4 replicates and 6 plants/plot. At the harvesting time, six fruits per plot were randomly collected for the following physicochemical analysis: fruit mass, pulp mass with and without seeds, length/longitudinal diameter, width/transverse diameter, length/width ratio, husk thickness, predominant color of the pulp (L*, C*, h*), number of seeds, seed size, total soluble solids content, total titratable acidity, total soluble solids/total titratable acidity ratio and pH. High heritability values ​​and relation of genetic/environment variation coefficients ratio were observed for most of the characteristics evaluated. The genotypes of yellow passion fruit MAR20#21 P2 x FB 200 P1 R2 and MAR20#19 ROXO R4 x ECRAM P3 R3 showed the best characteristics of fruit mass and pulp mass with seed. All the genotypes studied showed values ​​of total soluble solids above 11ºBrix. Positive and significant correlation was observed between fruit mass and length/width ratio, indicating that oblong fruits have higher fruit mass.

Passion fruit production under different swine wastewater doses treated in a biodigester

Soil fertilization using materials of animal origin, such as biofertilizers, is an important practice to maintain productive soil, as they provide beneficial effects on soil physical, chemical, and biological properties. This study aimed to evaluate the number of fruits, fruit mass, and yield of yellow passion fruits in the first year of cultivation with the application of swine wastewater (SW) treated in a biodigester. The experiment was set up at the experimental area belonging to IFCE Crato, CE, Brazil, with a spacing of 5.0 m between plants and 3.0 m between rows, using the espalier system of training and drip irrigation. The experiment was conducted in a randomized block design, with five treatments and four replications. Treatments consisted of five SW doses (D1 = 0, D2 = 0.50, D3 = 1.00, D4 = 1.50, and D5 = 2.00 L plant?1) applied at two phenological stages of the crop. The results were subjected to analysis of variance at a 5% significance, followed by the regression test. The increased SW doses influenced all the studied variables, following the linear and quadratic regression models, except for the mean fresh fruit mass. The highest yield was achieved with the highest studied dose, being an interesting alternative for recommendation to farmers in the region.

Cross-pollination affects fruit colour, acidity, firmness and shelf life of self-compatible strawberry

Cross-pollination affects the fruit characteristics of many crops but the effects of cross-pollination on fruit quality of strawberry (Fragaria × ananassa Duch.) are poorly known. This study determined how cross-pollination affects fruit quality of the strawberry cultivar, Redlands Joy, under controlled environment conditions. Plants were allocated to one of four treatments, with all flowers on each plant receiving either: (1) unassisted self-pollination (Autogamy); (2) hand-pollination with Redlands Joy pollen (Self); (3) hand-pollination with cross-pollen from a small-fruited cultivar (Sugarbaby); or (4) hand-pollination with cross-pollen from a large-fruited cultivar (Rubygem). Cross-pollination did not significantly affect plant yield or fruit mass, size, shape, firmness or shelf life. However, cross-pollination affected fruit colour and taste attributes. Cross-pollinated fruit were 3%–5% darker than self-pollinated fruit. They also had 26%–34% lower acidity and 43%–58% higher Brix:acid ratio. Cross-pollination by Sugarbaby increased fruit P, K, Ca, Fe and Mn, but decreased B, Cu and Zn, concentrations. Cross-pollination by Rubygem increased fruit Mn, but decreased K and Na, concentrations and reduced shelf life. Fruit mass, length, diameter and firmness within all treatments increased with increasing numbers of fertilized seeds per fruit. Hand self-pollinated fruit had a higher percentage of fertilized seeds than fruit arising from autogamy and they were also darker, redder, firmer, and had a longer shelf life, higher protein concentration, and lower Al and Na concentrations. The results indicate that strawberry fruit quality can be affected by both the source of pollen and the number of stigmas pollinated.

The Yield, Fruit Quality and Some of Nutraceutical Characteristics of Saskatoon Berries (Amelanchier alnifolia Nutt.) in the Conditions of Eastern Poland

The Saskatoon berry (Amelanchier alnifolia Nutt.) is a prospective and increasingly popular species in Poland. Its main attributes are extremely valuable fruits, rich in anthocyanins with high antioxidant activity, which are very valuable in processing. Studies aimed at comparing the suitability for cultivation under the climatic and soil conditions of east Poland of the three Canadian cultivars of Saskatoon berry (‘Honeywood’, ‘Martin’ and ‘Pembina’), were conducted at the Warsaw University of Life Sciences in 2017–2018. The study evaluated parameters such as yield and fruit quality, as well as the health-promoting value of the fruit. These studies revealed significant differences between the studied cultivars, both in yield and in fruit physicochemical properties, i.e., fruit mass and diameter, firmness, and soluble solids content, as well as in terms of the content of anthocyanins, flavonoids, and polyphenols. These differences were also found between years, which may indicate that the content of the abovementioned compounds is also influenced by annual climatic conditions.