Valeria Pergolotti

Recently, consumers have shown increasing interest not only in healthier food but also in products labelled as “free-from”. Among these, foods free of substances that can trigger allergic reactions in hypersensitive individuals, such as nickel, are of relevance. In this context, a two-year study was conducted in a soilless strawberry production system managed to minimise nickel inputs, to assess the feasibility of producing fruits complying with the “nickel-free” limit of 0.01 mg kg⁻¹. The experiment involved two strawberry cultivars (‘Asia’ and ‘Arianna’) and two plant types for each cultivar (tray plants and cold-stored A+ plants), grown in a 100% perlite substrate. Productive parameters, organoleptic quality, nutritional traits, and nickel content in fruits were evaluated. The aim was to determine differences among cultivars and plant types in yield, fruit quality, and nutritional value, and to verify whether the plant type affects nickel transfer to the fruit. Yield was highest in ‘Asia’ cold-stored plants, while ‘Arianna’ tray plants showed the best qualitative profile. Fruit nickel exceeded the limit in all combinations in the first autumn, but thereafter remained below it only in tray plants, showing that plant material choice, rather than the inert substrate alone, determines the production of nickel-free fruits.

Small fruits are increasingly popular among consumers and producers, with blueberries standing out for their flavour, nutritional benefits, and specific growing requirements. However, cultivation can be challenging in areas with alkaline soils, such as the mid-Adriatic region of Italy, where plant growth is limited. Soilless cultivation provides a practical and profitable solution to these issues, albeit with higher initial costs. This study examined Vaccinium corymbosum ‘Duke’ grown in soilless conditions in the Marche region (Italy) using different concentrations of nutrient solutions. Nutrient concentration was measured by electrical conductivity (EC) in fertigation with three treatments—T1 (790 µS cm⁻¹), T2 (890 µS cm⁻¹), and T3 (990 µS cm⁻¹)—compared with irrigation water (EC = 390 µS cm⁻¹). Results showed that T2 produced the highest numbers of wood and flower shoots and the greatest yield. Although nutrient levels did not significantly affect quality parameters, plants with lower nutrient intake (T1) displayed higher anthocyanin content and antioxidant capacity. In contrast, those with greater nutrient supply showed higher polyphenol content. Overall, the findings highlight the potential of soilless cultivation to optimize blueberry production under suboptimal soil conditions.

In strawberry (Fragaria × ananassa Duch.) breeding programs, seed dormancy adversely affects germination, resulting in delayed seedling emergence and low germination rates. This study investigated the best solution to enhance strawberry seed germination both in terms of efficiency and timing by evaluating the effect of three key factors: genotype, pre-sowing treatment, and germination medium. Chemical scarification treatment with the sulfuric acid of seeds from three different genotypes was optimized; treated seeds were placed to germinate on three germination media (Murashige and Skoog medium, peat, and filter paper) in a growth chamber. Seedlings obtained were acclimatized for evaluating post-acclimatization survival rate and possible phenotypic differences regarding seedling development. Chemical scarification treatment produced the best results, with germination rates of around 100% and the highest speed of germination compared to the not-treated controls. Indeed, more than 90% of the seeds germinated 14 days after sowing, regardless of the genotype or germination medium tested. Seedlings germinated on filter paper gave the poorest performances in terms of post-acclimatization survival rate and showed lower average plant height. In conclusion, it was demonstrated that excellent germination rates can be achieved through proper seed scarification, which is not genotype dependent; furthermore, when this method is combined with the correct germination medium, excellent seedling quality can be achieved.

Nitrogen plays a vital role in plants’ biochemical and physiological functions, and it contributes significantly to increasing plant yield and fruit quality. Plants that efficiently absorb and utilize nitrogen enhance the efficiency of fertilizers, reducing their input costs and preventing ecosystem damage. Thus, an adequate nitrogen supply can significantly improve plant growth, fruit quality, and nutritional value. This research focused on evaluating the plant vegetative and productive performance and fruit quality of three short-day strawberry genotypes (“Cristina”, “Romina”, and “Sibilla”) that were fertilized with different amounts of nitrogen, in a crop that was protected under a plastic tunnel. The trial was conducted during two cultivation cycles. The nitrogen rates were 113, 90, and 68 kg/ha for the first year, and 118, 97, and 76 kg/ha for the second. Reduced nitrogen inputs did not significantly affect plant height, indicating that decreased nutritional intake does not harm plant development. The fruit sugar content value remained stable across all nitrogen supplies, as did the fruit titratable acidity. The cultivars maintained a medium fruit firmness at a 60% nitrogen supply, and the Chroma index was not affected. This study found that reducing nitrogen inputs did not have a significant negative impact on the three tested cultivars, making them suitable for cultivation with reduced nitrogen inputs to reduce the environmental impact and save growers’ inputs.

The present study assessed the responses, in terms of vegetative, productive, qualitative, and nutritional features, of plants and berries of three remontant strawberry cultivars cultivated in soil and irrigated using three irrigation regimes: standard irrigation regime (W100), 20% (W80) less irrigation than the standard irrigation, and 40% (W60) less irrigation than the standard irrigation. The tested plants were “Albion”, “San Andreas”, and “Monterey”, which were cultivated in the east coast area of Marche, Italy. Specifically, the study examined the response of the genotype to irrigation deficit, highlighting the performance of the “Monterey” cultivar, which showed improvement in terms of fruit firmness, folate content, and antioxidant capacity at the W80 irrigation regime without a significant yield reduction. In all the cultivars, when irrigation was reduced by up to 20% of the standard irrigation regime (W100), there were no significant losses of yield or reduction in the fruits’ sensorial quality or antioxidant activity. The results showed that the standard irrigation regime (W100) commonly adopted by the farmers in the Marche area uses more water than necessary. With more accurate water management, it will be possible to save almost 226 m³ of water per hectare per cultivation cycle.

In raspberry (Rubus idaeus L.) breeding programs, seed double dormancy causes delayed and low germination rates. In this study, an in vitro germination protocol was developed to increase raspberry seed germination rate and decrease germination time. This protocol was optimized on the cultivars “Polka” and “Tulamagic”, specifically, their open-pollinated seeds, by applying two different cutting types (transverse, or longitudinal), followed by two different treatments (direct in vitro culture at 24 °C, or 2 weeks at 4 °C followed by in vitro culture at 24 °C). The best results for both cultivars were obtained when seeds were cut transversally and directly cultured in vitro at 24 °C (germination rate 73–78%, starting germination time 4 days after treatment). The optimized in vitro protocol was applied to 14 different combination crosses, observing a germination frequency around 87%, and speed in line with “Polka” and “Tulamagic”. These results were compared to those from the 14 cross combinations having undergone acid scarification (95% H₂SO₄ for 30 min) and cold stratification (3 months), which, in comparison, only yielded a 25% average germination rate. The optimized in vitro protocol favors high germination efficiency for all raspberry genotypes tested, and presents advantages for the standardization of germination time and reduction in the parental genotypes’ impact on germination rate.

Genotype, environment, and cultivation system strongly influence strawberry yield and quality. Specifically, the growth of strawberry plants is dependent on the water supply. Nevertheless, the abuse of water in agriculture is necessitating the choice of the lowest water-consumptive plants. The following study showed the performance of ‘Romina’, ‘Sibilla’, and ‘Cristina’ cultivars, grown in open-field conditions, and treated with three doses of water (W): 100% local standard regime, and 20% (W80) and 40% (W60) reductions. The average amount of water administered for W100, W80, and W60 was 1120 m³ ha⁻¹, 891 m³ ha⁻¹, and 666 m³ ha⁻¹, respectively. The water treatment at W60 negatively affected the plant growth and yield, resulting in reduced plant height, leaf number, leaf length and width, and a minor yield. Instead, fruit quality showed higher values of total soluble solids and titratable acidity. Conversely, plants watered with W80 showed results similar to the control (W100) in terms of development and yield. In conclusion, it is possible to assume that a reduction of water is desirable, guaranteeing economic and environmental gains for farmers.