Standardisation of two line heterosis breeding in rice ( Oryza sativa L.) for Kerala

Abstract

The present investigation entitled “Standardisation of two line heterosis breeding in rice(Oryza sativa L.) for Kerala” was conducted in the Department of Plant Breeding and Genetics, College of Horticulture, Kerala Agricultural University during 2010-2013.The objectives of the study were to identify the promising TGMS lines of rice, for the production of two line hybrids suited to Kerala and to standardize the two line heterosis breeding programme. The experimental materials consisted of TGMS lines collected from Tamil Nadu Agricultural University and high yielding varieties of rice from different research stations of Kerala. The primary investigation was carried out at College of Horticulture, Vellanikkara to study the sterility/fertility behavior of TGMS lines .It was found that April and May seasons can be considered as the ideal period of exploiting 100 per cent sterility in rice for the hybrid seed production.Experiments at CRS Pampadumpara was the suitable location for TGMS line seed multiplication. The present study concluded that CST(Critical Sterility Temperature) ranged from 34.2 to 38.6 0 Cand CFT (Critical Fertility Temperature) ranged from 23.6 to 25.4 0 C. Natural pollination with suitable pollinator parents proved to be a viable method for the production of two line hybrid seeds.Aiswarya, Makom, Kanchana and Samyuktha were good general combiners whereas Kairali was a poor combiner . Per se performance and gca effects were not correlated for most of the characters evaluated. The two line hybrids TGMS 91S x Makom, TGMS82S x Aiswarya , TGMS 81S x Kairali, TGMS 81S x Kanchana, TGMS 91S x Kairali exhibited superior SCA effects for various characters in COH Vellanikkara . TGMS 82S x Samyuktha , TGMS 74S x Samyuktha, TGMS 81S x Aiswarya, TGMS 91S x Samyuktha, TGMS 74S x Kairali, TGMS 74S x Makom showed superior SCA effects for the characters studied at RARS Pattambi.Molecular analysis revealed that the number of alleles per locus ranged from 2 to 3. Polymorphic information content ranged from 0.291 (RM2) to 0.648 (RM132) with an average of 0.448. RM11 markers showed more number of alleles with PIC value more than 0.50 indicate the efficiency of this primer in detecting the most heterogenous accession. Cooking quality analysis of promising hybrids revealed intermediate amylose content and intermediate alkali spreading value for TGMS 91S x Makom , TGMS 91S x Kanchana, TGMS 81S x Makom and TGMS 81S x Aiswarya. TGMS 81S x MattaTriveni recorded highest grain and straw yield at COH Vellanikkara. TGMS 91S x Samyuktha was the best performer at RARS Pattambi.