Abbreviation: SSC, soluble solids concentration. The cost of publishing this paper was defrayed in part by the payment of page charges. Under postal regulations, this paper therefore must be hereby marked advertisement solely to indicate this fact.
Tommy E. Thompson
Variability in soluble solids concentration (SSC, °Brix) in liquid endosperm (LE) among individual pecan [Carya illinoinensis (Wangenh.) K. Koch] fruits and among fruits from different trees and cultivars using a sugar refractometer was determined at College Station, Texas, in 1997. Repeatability of readings from LE from the same fruit was excellent. Fruits from the same tree did not vary for SSC, but significant differences among clones were common. Soluble solids concentration appears to decrease as the fruit matures. The SSC values for two full-sib clones (one susceptible to water split and one resistant to water split) were similar. This information discounts the possibility that high osmotic water potential gradients alone induce the water split phenomenon. A wide range of SSC percents was recorded. A low of 0.5% was recorded for LE from a `Houma' fruit, while 6.1% was recorded for LE from a fruit from a drought-stressed `Burkett' tree.
Robert L. Long, Kerry B. Walsh, David J. Midmore, and Gordon Rogers
A common practice for the irrigation management of muskmelon (Cucumis melo L. reticulatus group) is to restrict water supply to the plants from late fruit development and through the harvest period. However, this late fruit development period is critical for sugar accumulation and water stress at this stage is likely to limit the final fruit soluble solids concentration (SSC). Two field irrigation experiments were conducted to test the idea that maintaining muskmelon plants free of water stress through to the end of harvest will maximise sugar accumulation in the fruit. In both trials, water stress before or during harvest detrimentally affected fruit SSC and fresh weight (e.g., no stress fruit 11.2% SSC, weight 1180 g; stress fruit 8.8% SSC, weight 990 g). Maintaining plants free of water stress from flowering through to the end of harvest is recommended to maximise yield and fruit quality.
Carlos H. Crisosto, R. Scott Johnson, Juvenal G. Luza, and Gayle M. Crisosto
The effect of irrigation management strategies on the quality and storage performance of `O'Henry' peaches [Prunus persica (L.) Batsch] was studied for two seasons. The deficit irrigation treatment induced a higher fruit soluble solids concentration and lower fruit weight. The excess irrigation treatment, compared to the optimum treatment, increased the rate of fruit water loss without altering fruit quality and storage performance. Scanning electron microscope observations indicated a higher density of trichomes on fruit from the deficit and optimum irrigation treatments than from the excess irrigation treatment. Light microscopy studies indicated that fruit from deficit and optimum irrigation had a continuous and much thicker cuticle than fruit from the excess irrigation treatment. These differences in exodermis structure may explain the high percentage of water loss from fruit from the excess irrigation treatment compared to the deficit and optimum irrigation treatments.
Teri A. Hale, Richard L. Hassell, and Tyron Phillips
The refractometer has been proposed as a rapid, inexpensive technique for determining sugar levels in fresh sweet corn (Zea mays). High performance liquid chromatography (HPLC) analysis of sugars in three phenotypes (su, se, and sh2) of sweet corn harvested at three maturities indicated that sucrose content was highly correlated with the total sugars (R = 0.95). Sucrose and total sugar concentration were significantly different among all phenotypes. Soluble solids concentration (SSC) was high in su and se compared to the lower SSC of sh2. Early, mature, and late harvested samples differed in sucrose and total sugar content. Sugar concentration varied within phenotypes at each maturity level. Sh2 indicated no difference in sucrose and total sugars at early and mature harvests, but increased at late harvest. In contrast, sucrose and total sugar content decreased between early and mature harvests, then increased to highest levels at late harvest in se and su phenotypes. Overall, phenotype SSC increased significantly from early to late harvests, probably due to increased water-soluble polysaccharides in the su and se cultivars. Unlike other crops, a negative relationship was found in sweet corn between SSC and sucrose or total sugars, with an overall correlation of –0.51. This relationship was most affected by maturity, especially mature and late harvested sweet corn. Among phenotypes, sucrose, total sugar, and SSC were poorly correlated. Our results indicate that a refractometer should not be used to estimate total sugars or sucrose of sweet corn.
David Del Pozo-Insfran, Christopher E. Duncan, Kristine C. Yu, Stephen T. Talcott, and Craig K. Chandler
The effects of cultivar, harvest date, and production year on the soluble solids and antioxidant phytochemical levels of 22 strawberry (Fragaria ×ananassa Duch.) genotypes grown in a winter annual hill (raised bed) production system were investigated. Fruit harvested in Jan. 2003 and 2004 were characterized by low polyphenolic content, but high concentrations of soluble solids and ascorbic acid; whereas fruit harvested in Feb. 2003 and 2004 generally had elevated polyphenolic concentrations, but lower levels of soluble solids and ascorbic acid. Annual variation in soluble solids and phytochemical composition was also observed among nine strawberry genotypes, which was likely attributable to variations in solar radiation and air temperature. `Earlibrite' was among the highest for soluble solids concentration on three of the four harvest dates, while `Carmine' was noted for its high phytochemical concentrations across harvest dates and years. The breeder selection `FL 99-117' emerged as a promising selection in terms of producing fruit with high concentrations of soluble solids and antioxidant phytochemicals.
Richard J. Campbell and Richard P. Marini
Abbreviations: DAFB, days after full bloom; FS, full sun; FW, fruit weight; L : D, length : diameter ratio; PPD, photosynthetic photon density PSR, percentage surface red; SSC, soluble solids concentration. The cost of publishing this paper was
Eric T. Stafne, Amir Rezazadeh, Melinda Miller-Butler, and Barbara J. Smith
weight of collected berries. Chlorophyll index in the leaves were measured after each harvest with a chlorophyll meter (SPAD-502; Konica Minolta Sensing, Osaka, Japan) in 2017. Fruit characteristics. Fruit quality including soluble solids concentration
Paul M. Chen, Diane M. Varga, and Eugene A. Mielke
Abbreviations: EJ, extractable juice; FF, flesh firmness; SSC, soluble solids concentration; TA, titratable acidity. Oregon State Agricultural Experiment Station Technical Paper no. 9834. This study was supported by the Winter Pear Control Committee
Mikal E. Saltveit Jr. and Abdel R. Sharaf
Abbreviations: SSC, soluble solids concentration; TA, titratable acidity. 1 Visiting scientist from the Horticulture Dept., Ain Shams Univ., Shobra El-Khama Cairo. The cost of publishing this paper was defrayed in part by the payment of page charges