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• For the first time, fruit detachment forces (FDF) were determined at different developmental stages in ten cashew cultivars. • FDF varied significantly at the different stages of fruit development among the studied cultivars. • Ratio of FDF to Fruit weight (FW) (FDW/FW) reduced with the development of the fruit in cashew. • FDFs information is useful for designing efficient harvesting machines and screening of genotypes for stress tolerance and mechanical harvesting. Cashew is an edible tree nut with great nutritional and industrial importance. Cashew fruit is unique because the true fruit (nut) grows attached to a swollen flower pedicel known as a hypocarp or cashew apple. The fruit detachment force (FDF), a quantitative measurement of the detachment of fruits from the stalk, is considered as an important parameter for the evaluation of the harvesting efficiency of machines, and the cultivar's potential for machine harvesting, and tolerances to biotic and abiotic stresses. There have been no studies on the evaluation of FDFs in cashew to date. In the current study, we investigated the detachment forces of fruits at ten different stages of development according to the BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) scale, a uniform coding system for different growth or phenological stages (701, 703, 705, 707, 709, 811, 813, 815, 817, 819) in ten cashew cultivars. Fruit weight (FW), FDF/FW ratio, and fruit firmness (FF) for different fruit development stages and fruit stalk scar area (SSA) of matured (819 stage) fruits were also studied. FDF, FW, FDW/FW and FF varied significantly at the different stages of fruit development among the studied cultivars. The FDF increased from 701 to 709 stages and then decreased from 709 to 819 stages in all the studied cultivars. The FDW/FW ratio reduced with the development and maturity of the fruit. In matured fruits (811–819 stages), FW and FF showed significant negative (p value = 0.028) and positive (p value = 0.015.) correlations, respectively, with the FDF. In contrast, the SSA had no significant influence on the FDFs. As the FDF has direct implications on the fruit removal efficiency, the results of this study will be useful for designing harvesting machines, screening genotypes for stress tolerance, and identifying the optimal harvesting stage in cashew. [ABSTRACT FROM AUTHOR]

European growers are demanding selective mechanical harvesting solutions, such as robotic solutions, because hand harvesting is extremely labour intensive. Mechanical harvesting depends on low fruit retention forces between fruit and plant. Over two consecutive growing seasons, including a winter greenhouse trial, more than 1 600 samples were taken to determine the fruit removal force of early stage cucumbers for pickling and canning. Compared to studies with other fruit the fruit removal force of cucumbers was fairly high and also showed a large degree of variation. A significant percentage of the harvest had stalk residues, which cause the expenditure of extra man-hours on the processing lines. It was therefore concluded, that mere pulling is not sufficient to disconnect the fruit. Harvesting robots require an extra device for ease of separation. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work was to evaluate the speed effect of a coffee harvester and its interaction with 'Conilon' coffee (Coffea canephora) clones on the mechanical harvesting efficiency. The experiment was installed in São Mateus, in the state of Espírito Santo, Brazil, in 2012, with 27 clones of early, intermediate, and late fruit ripening. The first harvest was performed after the plant cuttings at 0.5 m above the ground, in 2016, and the canopy renovation. The plants and the harvester were evaluated in 2018. The coffee harvester was tested at 0.6 and 0.8 km h-1. Measurements were performed for stripping and harvesting efficiencies, fruit loss on the ground, unstripped fruit, defoliation with manual and mechanized harvesting, fruit removal force, and fruit ripening degree. The tests with the coffee harvester indicated a technical feasibility of 88% average harvesting efficiency, and a 15% lower defoliation than the manual harvesting. The harvesting speed of 0.8 km h-1 results in higher stripping and harvesting efficiencies, in a lower percentage of loss on the ground, and in less unstripped fruit, regardless of the evaluated clones. Fruit removal force and ripening degree influence the stripping and harvesting efficiencies and the percentage of unstripped fruit of 'Conilon' coffee.

In the study, the effects of aminoethoxyvinylglycine (AVG) treatment and maturity stages on physicomechanical and chemical properties of the fruit of plum fruit (Prunus domestica cv. 'President') was investigated. The effect of AVG doses for each maturity stage on geometric mean diameter and surface area of plum fruit was statistically significant. The geometric mean diameter and surface area were higher on 4 August harvest date than the other harvest dates. The effect of AVG doses on the fruit volume and fruit mass of plum fruit were statistically significant for each maturity stage. While L*, b*, and C* colour characteristics of plum fruit for all AVG treatments increased according to maturity stages. The effect of AVG treatments on the fruit removal force (FRF) and fruit hardness of plum fruit was statistically significant. The FRF and fruit hardness for plum fruit were higher as 19.17 N and 2.48 kg for 200 mg L-1 AVG dose than the other AVG doses. The laminate and rubber friction surfaces offered the minimum and maximum friction with AVG dose treatments. The effect of AVG treatments on soluble solids content (SSC) and titratable acidity of plum fruit was statistically significant (p<0.01). The chemical characteristics such as pH and SSC of plum fruit were higher in AVG-0 treatment and the latest harvest date than the other AVG treatment and harvest dates. For this reason, post-harvest technology applications (transporting, processing, storing and packaging systems) of the plum fruit must be designed while taking these criterias into consideration such as physicomechanical and chemical properties. [ABSTRACT FROM AUTHOR]

In the study, physico-mechanical properties [geometric mean diameter (Dg), sphericity, surface area, weight (W), bulk and fruit density, color, fruit removal force (FRF), puncture and compression force, puncture and compression deformation, friction coefficient] and biochemical attributes [pH, soluble solids content (SSC), titratable acidity (TA), vitamin C, total phenolics (TPs), total monomeric anthocyanin (TMA) and total antioxidant capacity (TAC)] of cherry laurel fruits (Prunus laurocerasus) and stones were investigated. Geometric mean diameter, surface area, fruit weight, bulk and fruit density significantly increased, but L*, a* and b* values significantly decreased with the progress of ripening. Fruit removal force decreased from 5.04 N to 3.09 N. On the other hand, W/FRF increased with the progress of harvest date. Static friction coefficient of fruits significantly increased over plywood and silicone surfaces and friction coefficients of stones increased over plywood, galvanized mild steel and silicone surfaces with the progress of harvest date. The pH, SSC, vitamin C, TPs, TMA and TAC (according to FRAP and TEAC assay) values significantly increased with the progress of ripening. It was concluded that fruit maturity stage at harvest had significant impact on physico-mechanical attributes and bioactive compounds of cherry laurel fruits.

This study was carried out to investigate the effects of different AVG (aminoethoxyvinylglycine) treatments on pre-harvest fruit drop rates and ripening levels of ‘Jonagold’ apples. A total of 225 mg L-1 AVG dose was applied at once in a single application at different times or divided into doses and applied different times. Compared to control treatment, entire AVG treatments increased fruit removal force and significantly decreased the pre-harvest drop rates. AVG treatments applied at once (225 mg L-1) 8 or 4 weeks before the anticipated harvest time were found to be more effective than the divided treatments. AVG treatments inhibited ethylene biosynthesis and such an inhibition was more distinctive in single 225 mg L-1 treatments. AVG treatments decreased flesh softening, starch degradation rates and consequently retarded fruit ripening. The 225 mg L-1 AVG treatment applied 4 weeks before the harvest significantly increased L* value and hue angle both in the year 2010 and 2011. NAA (naphtaleneacetic acid) at 10 mg L-1 sprayed 4 and 2 weeks before anticipated harvest was found to be insignificant in control of pre-harvest fruit drops. NAA treatment decreased flesh firmness, and did not have any significant effects on ethylene biosynthesis.

In the study, physico-mechanical properties [geometric mean diameter (Dg), sphericity, surface area, weight (W), bulk and fruit density, color, fruit removal force (FRF), puncture and compression force, puncture and compression deformation, friction coefficient] and biochemical attributes [pH, soluble solids content (SSC), titratable acidity (TA), vitamin C, total phenolics (TPs), total monomeric anthocyanin (TMA) and total antioxidant capacity (TAC)] of cherry laurel fruits (Prunus laurocerasus) and stones were investigated. Geometric mean diameter, surface area, fruit weight, bulk and fruit density significantly increased, but L*, a* and b* values significantly decreased with the progress of ripening. Fruit removal force decreased from 5.04 N to 3.09 N. On the other hand, W/FRF increased with the progress of harvest date. Static friction coefficient of fruits significantly increased over plywood and silicone surfaces and friction coefficients of stones increased over plywood, galvanized mild steel and silicone surfaces with the progress of harvest date. The pH, SSC, vitamin C, TPs, TMA and TAC (according to FRAP and TEAC assay) values significantly increased with the progress of ripening. It was concluded that fruit maturity stage at harvest had significant impact on physico-mechanical attributes and bioactive compounds of cherry laurel fruits. [ABSTRACT FROM AUTHOR]

The effects of pre-harvest GA 3 treatments at different concentrations (0, 30 and 60 mg L −1 ) on fruit quality attributes [geometric mean diameter, flesh firmness, hue angle, fruit removal force (FRF), soluble solids content (SSC) and titratable acidity] and bioactive compounds (total phenolics, total anthocyanin and total antioxidant capacity) of 0900 Ziraat, Regina and Sweetheart sweet cherry ( Prunus avium L.) cultivars were investigated in 3 different harvest periods. GA 3 -treated Sweetheart fruits were significantly larger than the control fruits. Considering the hue angle values, it was observed that GA 3 treatments retarded red color development in all three cultivars. The loss in flesh firmness throughout the ripening period was significantly retarded with GA 3 treatments in all three cultivars. Fruit removal force was significantly higher in GA 3 -treated Regina and Sweetheart sweet cherries than in control fruits. The SSC values of GA 3 -treated fruits were generally lower than the control fruits. Total phenolics, total anthocyanin and total antioxidant capacity of GA 3 -treated fruits were also significantly lower than the control fruits. As compared to control treatment, total phenol content of Regina fruits with a week retarded harvest was 22 and 25% lower respectively in 30 and 60 mg L −1 GA 3 treatments. Similar results were observed. [ABSTRACT FROM AUTHOR]

Cultural control of pre-harvest drop has relied upon plant growth regulators. To investigate the effects of plant growth regulators on pre-harvest drop and fruit quality, 150, 300 and 600 mg L-1 aminoethoxyvinylglycine (AVG) and 20 mg L-1 NAA were sprayed to 'Red Chief' apple trees at 4 week before anticipated harvest date. Untreated trees were kept as control. Results revealed that all AVG treatments increased the fruit removal force and significantly delayed pre-harvest drop and fruit maturity. Pre-harvest drop generally was unaffected by NAA. Internal ethylene concentration decreased with increasing AVG concentrations. Fruits treated with 150, 300 and 600 mg L-1 AVG showed increased fruit firmness and titratable acidity and reduced soluble solids content. Red colour development and starch degradation were retarded by all AVG treatments. Fruits treated with AVG (300 and 600 mg L-1) had lower fruit mass, fruit width and fruit length. The effect of NAA on all quality parameters was similar to the control treatment. AVG treatments decreased pre-harvest drop by fifty percent relatively to control. [ABSTRACT FROM AUTHOR]

Abstract: Changes in olive growing techniques in the last years have shown the need for new bred cultivars able to replace the traditional ones today cultivated. In this work, seven new advanced selections recently obtained in the olive breeding program of Córdoba, Spain, and coming from crosses between ‘Arbequina’ and ‘Picual’ were evaluated for fruit traits and oil quality parameters. Fruit weight, oil and moisture content, ripening index, fruit removal force and fatty acid composition were analyzed once a month over the ripening season from September to December over two consecutive years. Analysis of variance showed that the genotype effect was the main contributor to the total sums of squares for most of the traits evaluated. However, high influence of year, harvest date and interactions was also observed in some cases. Significant differences between cultivars were observed for all the evaluated characters. Ranking correlations indicate that the evaluation in a single common harvest date could be a reliable indicator for a correct classification of advanced olive selections for the traits considered. This would avoid the need for repeated measurements throughout the season or for collection of samples at a common ripening index for comparison. The correlations observed among fruit characteristics and fatty acids could be of interest in future breeding programs for those traits and some of them confirm previous results with seedling progenies and other breeding selections. Among all the selections evaluated, UC-I-42-48 seems promising for its good fruit size, oil content and low fruit removal force. Additionally UC-I-2-35 could be highlighted for its high oleic acid content, although further evaluation will be carried out in the future to obtain a complete commercial evaluation under different environmental conditions. [Copyright &y& Elsevier]

Abstract: Fruit abscission in water dropwort (Oenanthe stolonifera DC.) was investigated by measuring fruit removal force (FRF) affected by fruit ages and plant hormones. FRF decreased rapidly 30 days after anthesis (DAA). Ethylene evolution increased rapidly at 35 DAA and ABA concentration increased gradually after 20 DAA. ACC and ethephon decreased the FRF of fruit explants and the promoting effect of ACC was delayed by silver thiosulphate and cycloheximide, but not by norbornadiene and actinomycin D. ABA enhanced fruit abscission without increasing ethylene evolution. However, the observation that CoCl2 delayed abscission induced by ABA indicates possible involvement of ethylene in the ABA effect. Treatment with NAA, fenoprop and IAA had no effect on 30 DAA fruit explants, but IAA delayed abscission of 25 DAA explants. This suggests that the effect of auxins may differ with fruit age when used as control agents. [Copyright &y& Elsevier]

Growth in diameter of fruits (follicles) of five cultivars of Macadamia intergrifolia Maiden and Betche followed a single sigmoidal pattern. A rapid increase in fruit diameter began 2 to 3 weeks after anthesis and continued until weeks 14 to 16. No further increase in size was observed after 16 weeks. Growth in fresh weight of the two cultivars observed also followed a tingle sigmoidal pattern. A rapid increase in fresh weight began 5 to 6 weeks after anthesis and continued until weeks 15 to 18. No further increase in fresh weight was evident after 18 weeks. Abscission of flowers and fruits occurred continuously from anthesis through fruit maturity and amid be separated into three periods. The first period of abscission occurred in the first 2 weeks after anthesis and commonly involved over 90% of the flowers. The second period of abscission occurred front 3 to 8 weeks after anthesis and commonly involved over 80% of the initial set of small fruit. This period of abscision occurred - to and concurrent with the rapid increase in growth. The third period of abscissa was gradual and occurred from 9 weeks after anthesis until maturity at 28 to 30 weeks. Measurement of ethylene evolution by fruits showed a peak during weeks 3 and 4. This was to the peak in relative abscission rate at week 5. The fruit removal force increased from anthesis through week 12 and decreased from week 24 through maturity. [ABSTRACT FROM AUTHOR]