title: Textural, nutritional and functional attributes in tomato genotypes for breeding better quality varieties.
abstract: BACKGROUND
  Screening of natural biodiversity for their better quality attributes is of prime importance for quality breeding programmes. A set of 53 tomato genotypes was measured for their textural [skin firmness, pericarp thickness, total soluble solids (TSS)], nutritional [phosphorus (P), potassium (K), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn) and titrable acidity (TA)] and functional (beta-carotene, lycopene and ascorbic acid) quality attributes.
  
  
  RESULTS
  Three sets of data (textural, nutritional and functional attributes) were obtained and analysed for their mutual relationships. Wide variations were observed in most of the measurements, e.g. skin firmness (coefficient of variability (CV) 269-612 g), pericarp thickness (CV 1.4-4.9 mm), potassium (CV 229-371 mg 100 g(-1)), iron (CV 611-1772 mg 100 g(-1)), ascorbic acid (CV 12-86 mg 100 g(-1)), suggesting that there are considerable levels of genetic diversity. Significant correlations (P < 0.05, 0.01) were also detected among different attributes of tomato genotypes, such as phosphorus and zinc with a correlation coefficient of 0.74, ascorbic acid and copper of 0.57, pericarp thickness and lycopene of - 0.52. However, there were no correlations between textural and nutritional attributes. Five factors were computed by principal component analysis that explained 66% of the variation in the attributes, among which all micronutrients other than iron, TSS, firmness and beta-carotene were most important. Functional attributes except beta-carotene played a less important role in explaining total variation.
  
  
  CONCLUSIONS
  This knowledge could aid in the efficient conservation of important parts of the agricultural biodiversity of India. These results are also potentially useful for tomato breeders working on the development of new varieties.
authors.affiliation: Vivekananda Institute of Hill Agriculture, Almora, Uttarakhand, India. s_supradip@yahoo.com
authors.forename: Supradip
authors.initials: S
authors.lastname: Saha
authors.forename: Nirmal K
authors.initials: NK
authors.lastname: Hedau
authors.forename: Vinay
authors.initials: V
authors.lastname: Mahajan
authors.forename: Gyanendra
authors.initials: G
authors.lastname: Singh
authors.forename: Hari S
authors.initials: HS
authors.lastname: Gupta
authors.forename: Anita
authors.initials: A
authors.lastname: Gahalain
mesh_terms: D000383:Agriculture / Q000379:methods; D000975:Antioxidants / Q000378:metabolism*; D018556:Crops, Agricultural; D005638:Fruit / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics*; D014644:Genetic Variation; D005838:Genotype; D018551:Solanum lycopersicum / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics*; D018977:Micronutrients / Q000032:analysis* / Q000235:genetics; D009753:Nutritive Value; D025341:Principal Component Analysis
chemical_list: D000975:Antioxidants; D018977:Micronutrients