Assessment of combining ability and heterosis involving root knot nematode resistant lines in tomato Cheema D.S., Singh H., Jindal S.K., Kaur Sukhjeet* Department of Vegetable Science, Punjab Agricultural University, Ludhiana-141004, Punjab, India *sk-randhawa@pau.edu
Online published on 29 March, 2016. Abstract The present investigation was carried in tomato using ten lines, 45 crosses and hybrid check TH-1 grown in a randomized complete block design with three replications. Analysis of variance for combining ability revealed that mean squares due to general and specific combining ability were highly significant for all the characters studied. Parents Acc. No.4, Acc. No.9, Acc. No.5 and Acc. No.1 were best general combiners for most of the traits. Genotypes Acc. No.4, Acc. No.9 and Acc. No.5 also had high degree of root knot nematode resistance. The crosses Acc. No.2 x Acc. No.8, Acc. No.2 x Acc. No.5 and Acc. No.7 x Acc. No.10 were best specific combiner for fruit weight, total yield, root knot nematode, dry matter, lycopene content, titrable acidity and TSS. Heterosis was observed for almost all the characters. The best performing crosses were Acc. No.2 x Acc. No.3 for total yield, number of fruit per plant, fruit weight, harvesting span, titrable acidity and lycopene content and Acc. No.2 x Acc. No.5 for total yield, number of fruit per plant, harvesting span, TSS, titrable acidity and lycopene content. Acc. No.2 x Acc. No.8 for total yield, number of fruit per plant, titratable acidity, dry matter and lycopene content and Acc. No.6 x Acc. No.10 for total yield, number of fruit per plant, TSS, dry matter and lycopene content. All these crosses also expressed maximum heterosis over respective better parent for these traits. The combination Acc. No.1 x Acc. No.9 and Acc. No.4 x Acc. No.6 had maximum fruit yield of 2.97 kg and 2.93 kg per plant and it showed 63.19 and 85.44 per cent increase over better parent, 67.80 and 65.54 per cent respectively increase over the standard check, TH-1 and also showed resistant reaction against root knot nematodes. Top Keywords Heterosis, combining ability, root-knot nematode. Top |