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The aim of the work was to study the growth, drought tolerance and biochemical characteristics of introduced cultivars (‘Jonkheer van Tets’, ‘Hollandische Rote’ and ‘Viksne’) and some selected Russian cultivars and red currant genotypes (‘Shchedraya’, ‘Natali’, 129-21-61, 111-19-81, 261-65-19 and 271-58-24). The studies were conducted between 2014 and 2018 under temperate continental climate conditions. The intensity of transpiration was determined by using a torsion balance. The soluble solid concentration (SSS – % Brix) of the fruits was determined by using a digital refractomer. The content of the sum of sugars was determined by the weight method according to Bertrand's method. Ascorbic acid content was then determined by the iodometric method. The total phenolic content was determined by a colourimetric method. Climatic conditions were found to have significant influence on the disease severity of the red currant genotypes, while the infections caused by Sphaerotheca mors-uvae increased in optimum seasons and damages caused by Pseudopeziza ribis increased in drought seasons. None of the selected genotypes was found to be resistant to any of the diseases/pests, but ‘Jonkheer van Tets’, ‘Hollandische Rote’ and 111-19-81 were less affected by these diseases/pests. Weight, yield and raceme length of berries and the number of berries in a raceme were found to be higher in optimum seasons, and different cultivars/genotypes had superior characteristics for different parameters. The highest berry weight was observed in the 261-65-19 genotype (0.65 g), while the highest yield was noted in ‘Hollandische Rote’ (15.6 t · ha−1). It was also found that the water content of leaves and transpiration have a strong positive relationship with soil moisture at a depth of 0–200 mm but a week correlation with soil moisture at a depth of 200–400 mm. Results also showed that the transpiration of leaves decreases in later developmental stages (July). Hierarchical clustering suggested four clusters: the introduced cultivars produced one cluster, Russian cultivars are another cluster, 261-65-19, 111-19-81 and 129-21-61 genotypes make up a third cluster and the 271-58-24 genotype (superior in terms of phenolic contents) forms the fourth cluster.

Prevention of postharvest losses has been a very important concern in the scientific world for many centuries, since adoption of an effective means to curtail such losses is believed to help in reaching sustainability in horticultural production and prevention of hunger around the world. The main means of deterioration in fruits, which may occur after harvest, include physiological changes/losses, physical losses, biochemical changes, changes in enzymatic activities and pathological deterioration. Among these, diseases cover the most important part; the losses due to diseases range from 5% to 20%, and this figure may extend up to >50% in the cases of certain susceptible cultivars. Fungicides have been the most important tool for the management of postharvest diseases for many years, together with hygiene, cold storage and packaging. However, due to the scientifically confirmed hazards of agro-chemicals on environment and human health, the acceptability of agro-chemicals decreased and scientists turned their attention towards natural alternatives. Most tropical and subtropical fruits contain a superficial cuticle, which helps them to regulate respiration and transpiration and protects against microbial decay. However, the waxy cuticle is generally being removed or damaged during washing or other handling practices. Therefore, the application of protective coatings (including wax) has been used in the fruit industry since the twelfth century, against microbial decay and for maintaining an acceptable standard of postharvest quality. This review aims to summarise and discuss the main natural products used for this purpose, to provide a broad-in-scope guide to farmers and the fruit storage sector.

This research was designed to test the combined efficacy of hot water dipping (HWD) and leaf extracts of Cistus creticus L. subsp. creticus on the storage quality of fresh Valencia oranges. Experiments were laid down according to a completely randomised design with 10 different treatments. Five replications, with five fruits in each replication, were used in the current study, and research was designed to continue for 150 days. Quality characteristics were observed with 30-days interval. The applications of this study were (1) Control [dipping in water at 25°C for 5 min]; (2) HWD at 50°C for 5 min; (3) HWD + Additives (A) [Arabic gum (0.2%), potassium sorbate (0.05%), citric acid (0.05%) and vitamin C (0.05%)] at 50°C for 5 min; (4) Additives alone at 25°C for 5 min; (5) 1.0% C. creticus leaf + HWD + A; (6) 1.0% C. creticus leaf + A; (7) 0.5% C. creticus leaf + HWD + A; (8) 0.5% C. creticus leaf + A; (9) 0.5% C. creticus leaf + HWD and (10) 0.5% C. creticus leaf. According to the results obtained, both the HWD and C. creticus, alone or in combination, were effective in preserving orange weight during storage, preventing pathogenic decay, maintaining visual quality and fruit firmness, delaying the reduction in titratable acidity, increasing ascorbic acid content and reducing respiration rate of the orange fruits. Results also suggested that the combined effect of HWD with C. creticus leaf extracts provided the highest efficacy.

Progression of the vegetation period and change of year are associated with variations in general climatic parameters, such as temperature, atmospheric pressure, humidity, radiation, precipitation, wind speed and others. Only limited knowledge is available about the effects of these parameters on the characteristics of quality of fruits especially those with successive ripening such as goji berry. In our study, fruits of goji berry were characterised based on physico-chemical properties within four different harvest periods, in two consecutive years. Based on the obtained results, it was found that the pomological characteristics were superior at the beginning of the production season, while the phytochemical properties were better at the end. Fruit length, width and weight characteristics were noted to decrease from the first harvest to the last by 21%, 18% and 33%, respectively, while the total anthocyanin, phenol and antioxidant activity properties increased by 264%, 48% and 105%, respectively. There was a decrease in fruit weight, fruit length and fruit width up to 15.9%, 18.3% and 6%, respectively and were directly associated with yield due to sink competition among fruits. Providing high ripening index that ensures more acceptable fruits, with high soluble solid content (SSC) and titratable acidity (TA) seems to be a very important breeding objective to meet consumer demands thanks to superior organoleptic quality. According to correlations, the synthesis of phenolic compounds increased in parallel with SSC rise and TA, which improved pomological properties too. It is thought that the obtained results may indicate the cultural processes and evaluation methods to be used for the harvested fruits.