Author(s):

S Saha, S Dutta, P Biswas, R Mandal, A Chattopadhyay and P Hazra

Abstract: Many ripening inhibiting mutants which lengthen the shelf life of the fruits have been investigated not only to understand fruit ripening but also to develop hybrids possessing increased keeping quality. The present investigation was outlined to characterize the ripening inhibitor (rin) mutant and its hybrids to explore the possibility of its commercial utilization. The genotype possessing the rin gene (BCT-111rin) was semi-determinate in growth habit with normal green leaf containing 164.27mg/ 100g fresh weight total chlorophyll content. Immature fruits with increased size of sepals were uniformly light green in colour containing 10.16mg/ 100g fresh weight chlorophyll as against the average of 11.03mg/ 100g in three normal genotypes. Fruits of the rin genotype had the lowest of 1.61% total sugar content and 0.36% titratable acidity in the fruit pulp. The fruits did not ripe and remained bright yellow till the end and lycopene content in the fruits was very low of 0.38 mg/ 100g fresh as against the average of 3.56mg/ 100g fresh weight in three normal genotypes due to highly down-regulated ripening related ethylene biosynthesis. Appreciable ascorbic acid content in the fruits (25.66mg/ 100g fresh weight) suggested that ascorbic acid synthesis in the fruits and fruit ripening event were uncorrelated physiological processes. The hybrids between the genotypes with rin/ rin gene and the genotypes possessing either dg/dg or Aft/Aft gene significantly enhanced all fruit morphological characters. The dg/Dg rin/Rin hybrid was the highest yielder (4.72kg fruit/ plant). Average of 3.50mg lycopene content/ 100g fresh of the 4 rin/Rin - - hybrids (Aft/ aft rin/Rin, dg/Dg rin/Rin, og^c / Og^c rin/Rin and hp-1/Hp-1 rin/Rin) was slightly lesser than the average of the three normal tomato lines indicating negative effect of the “rin” gene even in heterozygous condition on the carotenoid biosynthesis although such depressive effect was too inconspicuous to their use in commercial hybrid breeding programme.

Pages: 2345-2346  |  1338 Views  187 Downloads

Download (621KB)