absorbance change of 0.01 units per minute. All spectrophotometric analyses were conducted on a spectrophotometer (BioMate 3S; Thermo Fisher Scientific, Waltham, MA). Measurement of osmoregulatory compounds. Soluble sugar content was measured using the
Yun-Peng Zhong, Zhi Li, Dan-Feng Bai, Xiu-Juan Qi, Jin-Yong Chen, Cui-Guo Wei, Miao-Miao Lin, and Jin-Bao Fang
Haijie Dou, Genhua Niu, Mengmeng Gu, and Joseph G. Masabni
Chl b were calculated according to Porra et al. (1989) and were used to calculate Chl a+b concentration and Chl a/b ratio. Nutritional quality measurement. Six plants per treatment were randomly selected for measurements of soluble sugar percent
Xuelian Jiang, Yueling Zhao, Ling Tong, Rui Wang, and Sheng Zhao
acid content (OA), total soluble solids content (TSS), total soluble sugar concentration (TSSC), VC, and lycopene content (LYC), were measured during the fruit maturation and harvesting stage. OA was titrated with 0.1 mol/L NaOH according to
Li-Juan Zhang, Tian-Xiu Zhong, Li-Xin Xu, Lie-bao Han, and Xunzhong Zhang
( A ), total soluble sugar ( B ), and total soluble protein ( C ) to soil moisture treatments in creeping bentgrass. 0D, 14D, and 35D represent 0, 14, and 35 d of treatment, respectively. Data represent the mean ± se (n = 4). Bars within each sampling
Iran Alia-Tejacal, Maria-Teresa Colinas-Leon, Maria-Teresa Martinez-Damian, and Marcos Soto-Hernández
Zapote mamey is a climacteric fruit that shows an increase in the content of carotenoids and total soluble sugars and in the activity of different enzymes during maturation. In the present study, zapote mamey fruits were harvested at physiological maturity and stored for 7, 14, and 21 days at 5, 10, and 15 °C, 85% relative humidity (RH). At the same time, immediately after harvest a group of fruits (control) was kept and evaluated at ambient temperature (20 °C, 50% to 60% RH). The objective was to determine the effects of temperature and storage time on content of carotenoids, and total soluble sugars, as well as to evaluate the enzymatic activity of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Fruits stored at 5 °C for 14 and 21 days developed chilling injury, as shown by a negative effect on carotenoids and total soluble sugars content. The activities of POD, CAT and SOD were also reduced after storage at 5 °C for 21 days. Fruits stored at 10 and 15 °C for 7, 14, and 21 days showed similar characteristics to the control fruits in carotenoids and total soluble sugars. Enzymatic activities were affected only by storage at 10 °C for 21 days. Storage at 15 °C for 21 days delayed, but did not stop maturation. Results suggest that zapote mamey fruits can be stored at 10 °C with no negative effect on quality.
Jack W. Buxton, Donna Switzer, and Guoqiang Hou
Marigold seedlings, 3 weeks old, were grown in natural light growth chambers at 3 day/night temperature regimes, 8°N/16°D, 13°N/20°D and 18°N/24°D, in a factorial combination with ambient and 1000-1500 ppm CO2. Seedlings were harvested at regular intervals during a 24 hr period and were analyzed for soluble sugars (reducing sugars and sucrose) and starch. Neither temperature nor CO2 concentration affected the accumulation of soluble sugars or starch during the day or night. The soluble sugar concentration ranged from 3% of dry weight at sunrise to 6% at mid-day; the concentration changed little during the night. Light intensity was different during replications of the experiment. Increased light intensity appeared to cause a slight increase in the soluble sugars maintained by the seedling during the day. Accumulated starch increased 6% to 8% from sunrise to late afternoon. Preliminary results indicate that light intensity greatly affected the concentration of starch. On the higher light intensity day, starch accumulated to a maximum of 18% of dry weight; whereas on the lower light intensity day the maximum concentration was 10%. During the night following the lower light intensity day, the starch concentration decreased to approximately 3% by the end of the night; following a brighter day the starch content was 13% at the end of the night.
Ming-Wei S. Kao, Jeffrey K. Brecht, and Jeffrey G. Williamson
coloration on each fruit. The fresh weight of individual fruit was measured using a weighing balance. Destructive analyses Soluble solids content, titratable acidity, pH, and total soluble sugar determination. About 100 g of frozen tissues were partly thawed
F.M. Woods, D.G. Himelrick, R. Aynaou, G.E. Boyhan, and T.M. Brasher
Changes in the activities of sucrose-metabolizing enzymes as related to ontogeny and ripening were studied in fruit mesocarp tissues of watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai, cvs. A.U. Producer and Sweet Scarlet]. The levels of soluble sugars and the activities of sucrose synthase (SS; EC 220.127.116.11), sucrose-phosphate synthase (SPS; EC 18.104.22.168), and invertase (INV; EC 22.214.171.124) were measured. The temporal pattern of these enzymes relative to the levels of soluble sugars were similar for both cultivars. `Sweet Scarlet' was characterized by having higher INV and SPS activities, while SS activities tended to be similar in both cultivars during fruit development. During later stages of ripening, `Sweet Scarlet' tended toaccumulate reducing sugars, while `AU Producer' tended to accumulate sucrose and therefore had lower sucrose-cleaving enzyme activity. Results indicate that SPS and INV appear to play a prominent role in carbohydrate metabolism in developing and ripening tissues of watermelon.
M. Hossein Behboudian and Colin Tod
The effect of preharvest CO2 enrichment (1000 μl·liter–1) on postharvest quality of tomato fruit (Lycopersicon esculentum Mill. `Virosa') was studied with an emphasis on soluble sugars, ripening, and mineral composition. High-CO2 fruit had higher concentrations of sucrose, glucose, fructose, and total soluble solids than ambient-CO2 fruit. High-CO2 fruit also ripened more slowly and was characterized by lower respiration and ethylene production rates than ambient-CO2 fruit. Concentrations of N, P, and K were lower in the high-CO2 fruit than in the ambient-CO2 fruit, whereas those of S, Ca, and Mg were the same for both treatments. Preharvest CO2 enrichment of `Virosa' tomato enhances fruit desirability in terms of slower postharvest ripening and higher concentrations of soluble sugars and total soluble solids.
Richard Allen Hamman Jr. and Imed Eddine Dami
Field studies were conducted to determine the effect of three drip irrigation regimes on grapevine growth, juice and wine quality, soil moisture, cold hardiness of bud and cane tissues and soluble sugar content of cortical cane tissues of Vitis vinifera, Linnaeus `Cabernet Sauvignon'. This study was developed to help provide some irrigation management strategies that would improve fruit quality and reduce excessive vigor. Irrigation treatments of 192, 96, and 48 L (51, 25, and 13 gal) per vine per week were initiated at bud break until veraison (initiation of berry color) and then reduced by 25% through harvest. Significant differences of fruit weight per vine, crop load, soil moisture, average berry and cluster weight, shoot length and pruning weight per meter of canopy row were observed among treatments. Juice and wine compositions and wine color were also significantly different; however, cold hardiness and soluble sugar contents did not differ between treatments.