The use of vented clamshells has become popular in the packaging of grapes for local and international markets. The aim of this study is to evaluate the postharvest preservation of ‘Benitaka’ table grapes individually packaged in vented clamshells using different types of SO₂-generating pads and perforated plastic liners during cold storage. A completely randomized design with four replications in a two-factor arrangement with an additional treatment [(4 × 3) + 1] was used. The trials were carried out under two situations: Artificial or natural infections with Botrytis cinerea, which is the causal agent of gray mold on table grapes. The incidence of gray mold, shattered berries, and stem browning were evaluated at 30 and 45 days of cold storage at 1 ± 1 °C and 3 days of shelf-life at 22 ± 1 °C after the period of cold storage. Mass loss and berry firmness were also examined at the end of the cold storage period. The use of dual-release SO₂-generating pads containing 5 or 8 g of a.i. and slow-release pads with 7 g of a.i. was effective in controlling the incidence of gray mold in grapes packaged in vented clamshells and kept under cold storage for up to 45 days. Under these storage conditions, perforated plastic liners with 0.3% ventilation area or micro-perforated liners with 1.0% ventilation area reduced the percentage of mass loss and shattered berries.

The purpose of this research is to test the efficacy of different types of SO₂-generating pads on the incidence of gray mold, and on the physicochemical properties of quality of ‘BRS Nubia’ seeded table grapes grown under protected cultivation. Four types of SO₂-generating pads, 5 or 8 g of sodium metabisulfite dual release pads, and 4 or 7 g of sodium metabisulfite slow release pads, were used. Grapes bunches were harvested from a vineyard covered with plastic mash and stored in a cold room at 1 ± 1 °C for 45 days followed by 6 days of shelf life at 22 ± 1 °C at a high relative humidity (>95%). The results showed that SO₂-generating pads with a dual release of 5 or 8 g completely inhibited the development of gray mold at all evaluation times. Also, a high reduction of the disease incidence was achieved by using a slow release of 4 g. The study confirmed that SO₂-generating pads did not alter the physicochemical properties of ‘BRS Nubia’ seeded table grapes including mass loss, berry firmness, color index, total anthocyanin concentration, total soluble solids (TSS), titratable acidity (TA), and the TSS/TA ratio. Slow release pads at 4 and 7 g reduced the percentage of shattered berries by 56 and 48% as compared to control only after 6 days of shelf life. Also, all types of SO₂-generating pads reduced the stem browning score at the end of cold storage. The 5 or 8 g dual release pads and 4 g slow release pads can be considered for effective controlling of gray mold for ‘BRS Nubia’ table grapes grown under protected cultivation while maintaining grape quality.

SO2-generating pads reduce gray mold in clamshell-packaged ‘Rubi’ table grapes grown under a two-cropping per year system

The objective of this work was to evaluate the rooting of herbaceous cuttings of CAMB-06 and APU-04 acerola cherry selections associated with the use of indolebutyric acid (IBA) and a concentration of aqueous extract of coco-grass. Cuttings were treated by immersion with different concentrations of IBA (0; 1,000; 2,000; 3,000; 4,000 mg L-1) and one application of aqueous extract of coco-grass in proportion 100% and placed to root in plastic boxes containing vermiculite. The experimental design was a completely randomized in a 2×6 factorial arrangement (two acerola cherry selections and six solutions for rooting) with four replicates of ten cuttings. After 90 days of cutting, the following variables were evaluated: cutting survival (%); leaf retention (%); rooted cuttings (%); sprouting (%); number of roots per cutting (%); length of roots (cm) and dry mass of roots per cutting (g). It was concluded that the application of IBA at 4,000 mg L-1 presented a better root development, resulting in a higher percentage of rooted cuttings and higher number and dry mass of roots in relation to IBA at 0 mg L-1 for CAMB-06 selection, while the APU-04 selection can be efficiently multiplied by herbaceous cuttings without the use of IBA. Under the conditions that the trials was conducted, the application of 100% aqueous extract of coco-grass was not effective in promoting the rooting of cuttings of CAMB-06 and APU-04 acerola cherry selections.

Cultivation of small fruits such as blackberry, raspberry, blueberry, strawberry, and physalis is rapidly growing in Brazil, mainly due to small producers who seek income diversification. The aim of this study was to evaluate the effect of foliar application of different doses of chitosan on the physicochemical properties of Physalis peruviana L. Two experiments were conducted: i) field (FE); and ii) greenhouse (GE). Four doses of chitosan (0.1, 0.2, 0.3, and 0.4 L 100L^-1) and a control were used as treatments. We evaluated fruit diameter (FD), fruit length (FL), calyx length (CL), and calyx diameter (CD) - mm; fruit mass - g; soluble solids content (SS) - °Brix; titratable acidity (TA) - % of citric acid; SS/TA ratio; and fruit firmness - N. Foliar application of chitosan to field-grown physalis plants significantly increased fruit mass, length, and diameter, as well as fruit SS and TA content. However, in a protected environment, the application of chitosan had less effect on the properties evaluated. Fruit firmness was not affected by chitosan application. Negative correlations (P<0.001) between fruit mass and firmness (r=-0.57) and SS/TA ratio (r=-0.61) were observed. SS/TA ratio was also negatively correlated with TA (r=-0.82), FL(r=-0.61), and FD (r=-0.68). High and significant correlations were observed between fruit mass and TA, FL, and FD. Foliar application of chitosan has a positive effect on both agronomic and chemical properties and can be an excellent alternative natural fertilizer for physalis plants when applied in doses up to 0.2 L 100 L^-1.