GASTI, V. D.SHIROL, A .M.EVOOR, SHASHIKANTHSHANTAPPA, .TMUTHAIAH, KOLA2018-07-062018-07-062015-09UHSBhttp://krishikosh.egranth.ac.in/handle/1/5810057898TH540The investigation on heterosis and combining ability in ridge gourd was carried out during 2014-2015 at the Department of Vegetable Science, Kittur Rani Channamma College of Horticulture, Arabhavi, Belagavi (Karnataka).Twenty eight crosses were developed by crossing eight lines in half diallel fashion. All F1 hybrids were evaluated along with parents in Randomized block design and data subjected to half diallel analysis. The magnitude of heterosis over the commercial check (Naga) was very high in desirable direction observed for the characters vine length (55.84%), number of leaves per plant (49.13%), number of branches (56.76%), days to first female flowering (-11.49%), nodes up to female flowering (-11.49%), sex ratio (-60.20%), per cent fruit set (36.205%), number of fruit per vine (18.41%), fruit length (45.55%), fruit diameter (24.20%), average fruit weight in (48.84%), fruits yield per vine (55.56%), fruit yield per plot (104.51 %) and fruit yield per hectare (104.72%). The hybrids which exhibited maximum heterosis for total fruit yield per vine over the commercial check (Naga) were DMRG-25 × DMRG-1 (55.56%) followed by DMRG-25 × DMRG-22 (48.15%), DMRG-36 × DMRG-25 and DMRG-25 × Arka Sumeet (46.30%). The crosses DMRG-25 × DMRG-1, DMRG-25 × Arka Sumeet, DMRG-36 × Arka Sumeet and DMRG-36 × DMRG-25 were identified as good specific combiners for total yield per vine. The parents DMRG-22, DMRG-36 and DMRG-25 were identified as good general combiners for total yield per vine in order of merit. Studies on combining ability variance revealed that non-additive gene action was predominant for fruit yield per vine, fruit yield per plot, fruit yield per hectare, sex ratio, per cent fruit set, number of fruits per vine, average fruit weight, fruit length, fruit diameter, vine length at 45 and 90 days to after sowing (DAS), number of leaves at 90 DAS, number of branches at 45 and 90 DAS, days to first female flowering, nodes to first female flowering and these characters could be further improved for combining ability through recurrent selection schemes or heterosis breeding.ennullThesis