www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 14.139.230.66 on dated 29-Nov-2016 Indian J Agric Biochem 20(1),17-22, 2007 Tomato (Lycopersicon esculentum Mill.) is one of the most popular and widely grown vegetables in the world ranking second in importance to potato. It is known for its outstanding nutritive and medicinal values and therefore grouped under body protecting foods. High consumption of tomato fruits is found significantly correlated with reduced risks of special type of cancer (1) and low incidence of “Ischemic” heart disease (2). The defensive role played by tomatoes is because of their high potentiality in providing some phytochemicals like ascorbic acid and carotenoids, particularly lycopene and α -carotene which accumulate in blood plasma due to their high consumption. Lycopene is as effective as α-carotene in inhibiting LDL oxidation, resulting with low risk of cardiovascular disease. Apart from this, lycopene has been found to be more efficient quencher of singlet oxygen thereby checking the destruction of vital molecules. Tomatoes also provide colour to the vegetable or dish wherever used and attract consumers and food processing industries. Tomatoes may be used as raw vegetable, salad as well as in some processed form such as sandwich, juice, drinks, ketchup etc. The quality of tomato fruits entirely depends on their developing stage. So, if harvested at immature stage, the colour, taste and flavour of fruits do not develop properly and hence, on storage, fruits get shriveled but otherwise, post-harvest shelf life is reduced, Studies on Quality Traits of Open Pollinated Varieties and Hybrids of Tomato Responsible for Their Shelf Life at Ambient Conditions MUKESH KUMAR, P SINGH, N SINGH, L SINGH and R N PRASAD Department of Agricultural Biochemistry, C S Azad University of Agriculture & Technology, Kanpur 208 002, India Quality attributes responsible for shelf-life of fruits of some promising open pollinated varieties and hybrids of tomato were analyzed at four durations of post-harvest storage i.e. 0, 3, 6 and 9- DAS at ambient conditions. The data on quality traits were statistically analyzed in split plot (in time) design. Open pollinated varieties/ hybrids exhibited significant variability in average fruit weight, TSS, dry matter, ascorbic acid, titrable acidity, reducing sugars, sugar/acid ratio and fruit spoilage in all the four conditions i.e. open pollinated varieties /hybrids over durations of post-harvest storage, post- harvest durations over open pollinated varieties /hybrids, same open pollinated varieties /hybrids at different duration of post-harvest storage alongwith overall interactions. Considering the quality traits of tomato under aforesaid four conditions, fruits of hybrid 9402x Azad Type-3 seem to be the superior most since they showed statistically maximum TSS (6.35 %), ascorbic acid (22.13 mg%), reducing sugars (3.54%), sugar/acid ratio (10.55) alongwith medium average fruit weight (70.66g), dry matter (7.36%) which are, in general, responsible for enhanced shelf life as tomato fruits of this hybrid showed no spoilage at 9-DAS followed by 8731 x Azad Type-3 (10%) and Azad Type-1(15%). Among correlation studies, TSS showed, by and large, significant positive association at all the four durations of storage with dry matter ( r = 0.4169, 0.5390, 0.5920 and 0.6751), ascorbic acid (r = 0.8362, 0.8963, 0.8971 and 0.8164), reducing sugars (r = 0.8967, 0.8329, 0.8323 and 0.8042), and sugar/ acid ratio (r = 0.7410, 0.7052, 0.9148 and 0.9265) . Key words: DAS, TSS, dry matter, sugar, ascorbic acid, titrable acidity, spoilage, tomato which may cause significant losses in quality during transportation, storage and marketing (3,4). The shelf life of tomato fruits, instead of genetic factors, also depends on content of calcium, titrable acidity and polygalacturonase alongwith pericarp thickness, fruit size and fruit firmness (5, 6, 7, 8). Evans (9) developed a tomato variety by modifying quality traits of its fruits type like dry matter etc. leading to increased shelf-life by somaclonal variation technique. Keeping this view in mind, the present study was undertaken to provide a quality base of tomato to its breeders so that they may utilize the same to develop tomato varieties having superior quality and enhanced shelf life. Materials and Methods About 2 kg red ripe fruits of each of open pollinated varieties viz. Azad Type-1, Azad Type-3, Azad Type-5, Azad Type-6 and hybrids like K.T.H-1 (KS-7x Azad Type-3), K.T.H.-2 (Azad Type-3 x Angoorlata), F 1 -14 (9402 x Azad Type-3) and F 1 -23 (8731 x Azad Type-3) were collected from all the replications from a S.V.T. on tomato laid out at Vegetable Research Farm of the Deptt. of Vegetable Science and brought to the Vegetable Quality Laboratory of Agril. Biochemistry Deptt. of this University for storage at ambient conditions having temperature and relative humidity range between 16.20 to