A physiological and genetic approach to the improvement of tomato (Lycopersicon esculentum Mill. ) fruit soluble solids
Physiological processes and the genetic basis determining soluble solids content (SSC) of processing tomato fruit were addressed. Analysis of ({sup 3}H)-(fructosyl)-sucrose translocation in tomato indicates that phloem unloading in the fruit occurs, at least in part, to the apoplast. Apoplastic sucrose, glucose and fructose concentrations were estimated as 1 to 7, 12 to 49 and 8 to 63 millimolar, respectively in tomato fruit pericarp. Short-term uptake of ({sup 14}C)sucrose, -glucose and -fructose in tomato pericarp discs showes first order kinetics over the physiologically relevant concentration range. The uptake of ({sup 14}C)-(glycosyl)-1{prime}fluorosucrose was identical to the rate of ({sup 14}C) sucrose uptake suggesting sucrose may be taken up directly without prior extracellular hydrolysis. Short-term uptake of all three sugars was insensitive to 10 micromolar carbonyl cyanide m-chlorophenylhydrazone and to 10 micromolar p-chloromercuribenzene sulfonic acid. However, long-term accumulation of glucose was sensitive to carbonyl cyanide m-chlorophenylhydrazone. Sugar uptake across the plasmamembrane does not appear to be energy dependent, suggesting that sugar accumulation in the tomato is driven by subsequent intracellular metabolism and/or active uptake at the tonoplast. Fourteen genomic DNA probes and ten restriction endonucleases were used to identify restriction fragment length polymorphisms (RFLPs) useful in the linkage analysis of quantitative trait loci controlling the expression of SSC in a segregating F{sub 2} population from a cross between L. esculentum (UC204B) and L. cheesmanii f. minor, a wild species with high fruit soluble solids. RFLPs were detected between the DNAs of the two tomato species with all 14 probes.
- Research Organization:
- California Univ., Davis, CA (United States)
- OSTI ID:
- 5671432
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
TOMATOES
GENE REGULATION
CARBON 14 COMPOUNDS
CHEMICAL COMPOSITION
DNA SEQUENCING
ENDONUCLEASES
FRUCTOSE
GLUCOSE
PHYSIOLOGY
SACCHAROSE
TRACER TECHNIQUES
ALDEHYDES
CARBOHYDRATES
CARBON COMPOUNDS
DISACCHARIDES
DNA-ASE
ENZYMES
ESTERASES
FOOD
FRUITS
HEXOSES
HYDROLASES
ISOTOPE APPLICATIONS
KETONES
LABELLED COMPOUNDS
MONOSACCHARIDES
OLIGOSACCHARIDES
ORGANIC COMPOUNDS
PHOSPHODIESTERASES
SACCHARIDES
STRUCTURAL CHEMICAL ANALYSIS
550201* - Biochemistry- Tracer Techniques