Current Advances in Agricultural Sciences 8(1): 55-57 (June 2016) Print ISSN 0975-2315 DOI : 10.5958/2394-4471.2016.00011.3 Online ISSN 2394-4471 Principal component analysis for yield and its contributing traits in bread wheat (Triticum aestivum) genotypes under late sown condition JAYDEV KUMAR*, ANUJ KUMAR 2 , SK SINGH, LOKENDRA SINGH, ARUN KUMAR 1 , MOHIT CHAUDHARY 3 , SARVAN KUMAR 2 and SANJAY KUMAR SINGH 2 Department of Genetics and Plant Breeding, C.S. Azad University of Agriculture and Technology, Kanpur-208 002 (Uttar Pradesh), India *Email of corresponding author: jaydev.140@rediffmail.com Received: 19 October 2015; Revised accepted: 15 May 2016 ABSTRACT Genetic diversity is a useful parameter that facilitates production of more efficient plant species under different conditions. Accordingly, the most common bread wheat (Triticum aestivum L. emend, Fiori & Paol.) genotypes including 10 diverse parents with their F 1 s were grown in late sown condition and analyzed for genetic diversity and heritability. The high narrow sense heritability was observed for days to 75% flowering (45.63), days to maturity (37.55), chlorophyll fluorescence (Fv/Fm) (39.90) and protein content (31.52). The divergence analysis based on Euclidian methods indicated the presence of adequate genetic diversity in the experimental materials. The fifty five wheat genotypes were grouped into eight clusters. Cluster I had maximum (14) genotypes, while Cluster VI contained only one genotype. The maximum inter-cluster distance was observed among cluster VI and cluster VIII. The result of the principal components analysis revealed that six principal components (PC1 to PC6) accounted for nearly 81.75% of the total variation. The information so generated could be used to plan crosses and study the extent of heterosis. Key words: Bread wheat, Genetic diversity, Heritability, Principal components, Triticum aestivum qualitative and quantitative traits in order to select genetically distant parents for hybridization (Arega et al., 2007; Ahmadizadeh et al., 2011; Daniel et al., 2011). The present study was undertaken to assess the magnitude of genetic diversity and characters contributing towards total genetic diversity in some bread wheat genotypes for its utilization in further wheat breeding programs. MATERIALS AND METHODS Ten diverse genotypes were crossed in all combinations (excluding reciprocals) to produce 45 F1 crosses during 2013- 14. These 45 F1 crosses along with 10 parents were grown during rabi 2014-15 following complete randomized block design at Crop Research Farm, Nawabganj of C.S. Azad University of Agriculture and Technology, Kanpur (Uttar Pradesh), India under late sown condition (15 December 2014). The experimental materials were replicated thrice and distance maintained within row and between rows were 5 cm and 20 cm, respectively. Recommended dose of fertilizers (120:60:40 kg NPK ha -1 ) and 4 irrigations were applied for better crop production. The data on 18 qualitative and quantitative characters were recorded from mean values of ten randomly selected plants from each genotype per replication. The observation were taken for days to 75% flowering, days to maturity, duration of reproductive phase, plant height (cm), number of effective tillers plant -1 , number of spikelet spike -1 , number of grains spike -1 , grain weight spike -1 , spike length (cm), biological yield plant -1 (g), harvest Index (%), 1000-seed weight (g), spike density, canopy Wheat (Triticum aestivum L. emend, Fiori & Paol.) is one of the most important cereal crop of the world both in terms of area (223.5 million hectare) and production (734.05 million tonnes) during 2014-15. Wheat is used mainly for human consumption and supports nearly 35% of the world population. It is nutritious, easy to store and transport and can be processed into various types of food. The demand for wheat is expected to grow faster than any other major agricultural crop. To meet the needs of the growing world population, the projected demand by the year 2020 has been put between 840 (Rosegrant et al., 1995) and 1050 million tonnes (Kronstad, 1998). In order to meet world’ s food demand wheat production growth has to be increased to more than two percent per annum. Keeping in view of limited resources and little scope for area expansion, productivity enhancement is the only option to meet anticipated food demand particularly for the wheat. For developing high yielding varieties through hybridization, parents should be selected based on combining ability and F 1 heterosis (Arunachalam, 1989). However, heterosis, in turm, is dependent upon the extent of genetic diversity (Singh et al., 2003). Several genetic diversity studies have been documented on different crop species based on Department of Genetics and Plant Breeding, G.B. Pant University of 1 Division of Crop Improvement, Indian Institute of Wheat and Barley Research, Karnal-132 001 (Haryana), India; C.C.S. University of Agriculture and Technology, Hisar-125 004 (Haryana), India 3 Agriculture and Technology, Pantnagar-263 145 (Uttarakhand), India; 2