to confidently draw conclusions from a study. Therefore, the objective of this study was to determine the optimum plot size and number of replications necessary to detect differences in yield, fruit size, fruit firmness, and soluble solids. Materials
T. Casey Garvey and John D. Hewitt
Abbreviations: SSC, soluble solids content; QTL, quantitative-trait loci. 1 Present address: Hunt Wesson, 1111 Coven Blvd., Davis, CA 95616. 2 Present address: Rogers NK Research, P.O. Box 1827, Gilroy, CA 95021-1827. We acknowledge the assistance
Lucianne Braga Oliveira Vilarinho, Derly Jose Henriques da Silva, Ann Greene, Kara Denee Salazar, Cristiane Alves, Molly Eveleth, Ben Nichols, Sana Tehseen, Joseph Kalil Khoury Jr., Jodie V. Johnson, Steven A. Sargent and Bala Rathinasabapathi
, thickness, antioxidant potentials, and total soluble solids. Materials and Methods Plant material and cultivation conditions. Seeds of C. annuum cultivars Bulgarian carrot and Round of Hungary were purchased from Park Seed Co. (Greenwood, SC) and Johnny
Steven J. MacKenzie, Craig K. Chandler, Tomas Hasing and Vance M. Whitaker
peak bloom. Soluble solids content is the collective concentration of sugars, acids, and other substances dissolved in the cell sap. In strawberry, sugars comprise 80% to 90% of the SSC ( Perkins-Veazie, 1995 ). Fruit SSC is usually satisfactory for
Gerald G. Dull, Richard G. Leffler and Gerald S. Birth
An instrument based on near infrared (NIR) reflectance techniques is described which is capable of determining nondestructively the percent soluble solids in whole honeydew, cantaloupe and watermelon samples. It utilizes a tilting interference filter technology for wavelength scanning and a silicon detector/amplifier for the detection of radiation which has penetrated through inner melon flesh. The standard error of prediction is of the order of 1.2 percent soluble solids for honeydew melons when compared with a standard refractometer analysis.
Gad G. Yousef, Shyh-Shyan Wang and John J. Juvik
A segment from chromosome 7 of the wild tomato species, Lycopersicon chmielewskii has been introgressed through backcrossing into the processing cultivar, VF145B-7879. This segment was previously shown to carry a gene or genes that increase the soluble solids content in ripe red tomato fruits. To study the allelic interaction of this gene(s) and ascertain its performance in different genetic backgrounds, this line, homozygous for the L. chmielewskii segment, was crossed to its isogenic parent (VF145B-7879) and three other commercial cultivars (UC204c, E6203, and ChicoIII). The recurrent parent VF145B-7879 was also crossed to the other cultivars to generate two sets of hybrids, one heterozygous for the L. chmielewskii segment and the other homozygous for the L. esculentum segment on chromosome 7. Results from two years of field study revealed that the L. chmielewskii fragment, when either homozygous or heterozygous in the VF145B-7879 background, comparably increased soluble solids concentration in red fruit, suggesting dominant allelic interaction. This increase ranged from 8%–10% higher soluble solids content in these lines compared to the levels found in the recurrent parent (VF145B-7879). The F1 hybrids containing one dosage of this gene(s) showed a significant increase in the soluble solids content compared to the commercial parents. However, due to F1 heterosis observed in all the hybrid combinations, soluble solids content in the hybrids with this gene were not significantly greater than that of the hybrids without this gene. This gene was found to exert no significant influence on fruit pH, weight, and yield.
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.
Gerald G. Dull, Richard G. Leffler and Gerald S. Birth
A near-infrared spectrophotometric method for estimating the soluble solids in honeydew melons is presented. The method is based on a body transmittance geometry in which the angle between the source incident beam and the detector is approximately 45°. The regression analysis of the spectral and chemical data utilizes a ratio of two second derivatives and resulted in a correlation coefficient of 0.85 and a standard error of calibration of 1.5. The numerator wavelength occurs in a carbohydrate absorption band, thus the method can be interpreted as a measurement of carbohydrates.
Graham H. Barry, William S. Castle and Frederick S. Davies
Juice quality of `Valencia' sweet orange [Citrus sinensis (L.) Osb.] trees on Carrizo citrange [C. sinensis × Poncirus trifoliata (L.) Raf.] or rough lemon (C. jambhiri Lush.) rootstocks was determined for fruit harvested by canopy quadrant and separated into size categories to ascertain the direct role of rootstock selection on juice soluble solids concentration (SSC) and soluble solids (SS) production per tree of citrus fruit. SS production per fruit and per tree for each size category was calculated. Juice quality was dependent on rootstock selection and fruit size, but independent of canopy quadrant. Fruit from trees on Carrizo citrange had >20% higher SSCs than fruit from trees on rough lemon, even for fruit of the same size. Large fruit accumulated more SS per fruit than smaller fruit, despite lower juice content and SSC. Within rootstocks, SS content per fruit decreased with decreasing fruit size, even though SSC increased. Rootstock effect on juice quality was a direct rather than an indirect one mediated through differences in fruit size. The conventional interpretation of juice quality data that differences in SSC among treatments, e.g., rootstocks or irrigation levels, or fruit size, are due to “dilution” of SS as a result of differences in fruit size and, hence, juice volume, is only partly supported by these data. Rather, accumulation of SS was greater for fruit from trees on Carrizo citrange than rough lemon by 25% to 30%.
Michael Thornton, James Torell and Daryl Richardson
A field study was conducted to determine the relationship between pungency, soluble solids content, and susceptibility to neck rot in onions. `Golden Cascade', `Sweet Amber', `Valdez', and `Vega' onions were planted in a field with low soil S content. Sulfur, as coarse-ground calcium sulfate, was applied as a band before planting. After harvest, yield was determined and a sample of jumbo onions was taken from each plot to determine pungency, dry matter content, and soluble solids content. Healthy bulbs were returned to storage and evaluated for neck rot after 4 months. Yield, grade, and neck rot incidence after storage were not affected by S treatments. However, there was a trend toward lower neck rot incidence at the highest S application rate (160 lb/acre). Pungency of jumbo onions increased after the application of S as gypsum. `Sweet Amber' and `Valdez' were less pungent than `Golden Cascade' or `Vega'. Neck rot susceptibility was evaluated with an inoculation test of detached bulb scales. Growth and sporulation of the neck rot pathogen Botrytis allii were reduced by S application. Pungency and neck rot susceptibility were negatively correlated.