Terpenes significantly affect the flavor and quality of grapes and wine. This review summarizes recent research on terpenoids with regard to grape wine. Although, the grapevine terpene synthase gene family is the largest identified, genetic modifications involving terpenes to improve wine flavor have received little attention. Key enzyme modulation alters metabolite production. Over the last decade, the heterologous manipulation of grape glycosidase has been used to alter terpenoids, and cytochrome P450s may affect terpene synthesis. Metabolic and genetic engineering can further modify terpenoid metabolism, while using transgenic grapevines (trait transfer to the plant) could yield more flavorful wine. We also discuss traits involved in wine aroma quality, and the strategies that can be used to improve grapevine breeding technology.

In this study, phosphorus (P) strength [(full strength: 1×-P, half strength: 0.5×-P and zero strength: 0×-P)] and root zone temperature (10 and 15 °C RZT) were investigated in red romaine lettuce to determine their effects on anthocyanin content. This experiment was conducted using a deep-flow technique (DFT) hydroponic system in a greenhouse during the winter in Gangwon province in the Korea Republic. The treatments were 1×-P (15 and 10 °C RZT), 0.5×-P (15 and 10 °C RZT) and 0×-P (15 and 10 °C RZT). The results showed that the P (phosphorus), K (potassium) and Ca (calcium) accumulation contents were lower in the 0×-P -treated red romaine lettuce leaves than in the other treatments. The maximum red romaine lettuce yields per plant, leaf number and leaf length were exhibited during the 1×-P at 15 °C RZT treatment. In 0×-P at 10 °C, RZT treatment showed lower leaf color values of L*, b*, chrome, ºh and higher leaf color a* values. Moreover, in the 0×-P treatment at 10 °C RZT, the leaf chlorophyll content (SPAD), chlorophyll a, chlorophyll b and chlorophyll total were the lowest. Anthocyanin content was the highest in the 0×-P treatment, followed by 0.5×-P and 1×-P treatments at both 15 and 10 °C RZT. Regardless of the P intensity treatment, anthocyanin content was higher at 10 °C RZT than at 15 °C RZT. In summary, the 1×-P at 15 °C RZT treatment is the best for red romaine lettuce leaf yield, and the 0×-P at 10 °C RZT treatment is the best for lettuce leaf anthocyanin content.

This study investigated the effect of preharvest treatment of 0.25 mM methyl jasmonate (MeJA) and 0.5 mM salicylic acid (SA) on quality parameters, most important secondary metabolites (lycopene, β-carotene, ascorbic acid, total phenolics, and flavonoids), antioxidant activities, and amino acid contents of ‘Kumato’ tomato. Treatments with MeJA and SA led to an increase of total yield per plant and were effective in maintaining the fruit quality attributes such as firmness, total soluble solids, titratable acidity, and Brix acid ratio at two maturity stages (S1 and S2). In addition, lycopene, β-carotene, ascorbic acid, total phenolics, and flavonoids were significantly higher in the treated fruit than in the control. Moreover, γ-aminobutyric acid (GABA), essential amino acids, and antioxidant activity increased due to MeJA and SA treatments at both stages, especially with MeJA treatment at S2. Overall results also showed the effectiveness of MeJA treatment than SA on improving the yield and nutritional quality of ‘Kumato’ tomato.

This study was conducted to investigate the effects of nutrient and salinity concentrations on the quality of deepflow technique hydroponic system cultivated cherry tomatoes (Lycopersicon esculentum Mill ‘Unicorn’). The conditions were: (1) control (NS-1 × nutrient Solution, Electrical Conductivity – EC: 2.5 mS∙cm^–1); (2) 2 × NS (2 × NS-Double NS, EC: 5 mS∙cm^–1); (3) NS + 4.23 mM NaCl (NaCl-Sodium Chloride, EC: 5 mS∙cm^–1); and (4) NS + 13.70 mM Sea Water – SW (EC: 7.5 mS∙cm^–1). NS + 13.70 mM SW treatment showed the lowest fresh weight loss. Visual quality as well as shelf life was the longest in NS (1 × nutrient solution) treated tomato fruits. The longest shelf life at 5 °C, 11 °C, and 24 °C were 21, 16, and 8 days, respectively, in NS (1 × nutrient solution) treated tomato fruits. The highest firmness was recorded in NS (1 × nutrient solution) treated tomato fruits, which was retained after storage. Moreover, NS + 13.70 mM SW treatment increased the cherry tomato fruit’s quality, especially soluble solids and sugar contents. These results indicate that salinity concentration has effect the soluble solids and sugar of cherry tomato fruits. In addition, nutrient concentration influenced the shelf life and firmness of cherry tomato fruits.

Recently, LEDs with various light qualities have been used in closed plant factories, and they are known to have different effects on the growth and quality of crops. Therefore, this study was conducted to investigate the change in growth and quality in mini red romaine lettuce using LEDs with various light qualities. Wide red spectrum (WRS)-LEDs, blue (B)-LEDs, blue + red (BR)-LEDs, red (R)-LEDs, and white (W)-LEDs were used as the artificial light sources. Regarding growth, the R-LED treatment showed the most positive effect, but the leaf shape was not normal and the Hunter b* value was not suitable because it was higher than that of the other treatments. The Hunter a*, SPAD, and NDVI values of the B- and BR-LED treatments were effective, but this was not the case for those of the R- and W-LED treatments. The anthocyanin reflectance index 1 (ARI1) was 20 times higher in the B-LED treatment than in the R-LED treatment, and the ascorbic acid content was the highest in the WRS-LED treatment. In the sensory evaluation, bitterness and sweetness showed opposite tendencies. Regarding the overall preference, the BR-LED treatment received the highest score. Correlation analysis showed that the bitterness was closely correlated with the anthocyanin content and leaf color. Taken together, BR-LEDs provided a good top fresh weight, dark red leaves, and high anthocyanin and ascorbic acid contents, with the highest overall preference; therefore, BR-LEDs were the most suitable for the cultivation of mini red romaine lettuce.