GENETIC VARIABILITY FOR NITROGEN USE EFFICIENCY (NUE) AND YIELD ATTRIBUTING TRAITS IN WHEAT

T.N. SATHISHA¹*, S.A. DESAI^2
1Department of Genetics and Plant Breeding, University of Agricultural Sciences, Dharwad, 580005, Karnataka
²Department of Genetics and Plant Breeding, University of Agricultural Sciences, Dharwad, 580005, Karnataka
* Corresponding Author : tnsathish64@gmail.com

Received : 03-06-2016     Accepted : 01-07-2016     Published : 18-10-2016
Volume : 8     Issue : 48       Pages : 2010 - 2014
Int J Agr Sci 8.48 (2016):2010-2014

Keywords : Morpho- physiological, NUE, NUpE, NUtE and grain yield
Academic Editor : Dr A. V. S. Durga Prasad, Kumaruttam
Conflict of Interest : None declared
Acknowledgements/Funding : None declared
Author Contribution : None declared

An experiment was conducted to study the genetic variability, heritability and expected genetic advance for morpho-physiological, yield and NUE component traits in wheat accession under two different N levels. A set of 84 wheat genotypes was evaluated at two different nitrogen regimes, the T0 (without an external supply of nitrogen) and T1 (100 kg N/ha, RDF). All the characters studied, have shown good amount of variability in the genotypes. The mean performance of physiological traits like NDVI and SPAD, yield related traits like the number of tillers per meter row, spikelet’s per spike, spike length (cm), thousand grain weight (g) and seed yield (q/ha) and nitrogen use efficient traits like grain N, straw N, nitrogen uptake efficiency (NUpE) was found to be higher under the treatment with external supply of nitrogen (T1) than under the nitrogen stress treatment (T0). The high PCV and GCV values were recorded for trait grain yield, biomass and NUE, which indicates that, these characters have high variability that in turn offers good scope for selection. The high heritability estimates along with high genetic advance was obtained for NDVI at anthesis stage, days to fifty percent flowering, spike length, grain yield, biomass, harvest index (%), straw N, NUtE, NUpE and NUE. These traits are the most important to be taken into consideration for effective selection in wheat for NUE. Based on the four key variables determining N-efficiency in a wheat crop are grains N, NHI, high grain yield and high nitrogen use efficiency can be considered as important criteria for selection of high NUE in wheat. The genotypes viz., 2nd WYCYT 34, 3 rd SATYN 9403, 5th CISA HTEM 10212 and WH 1022, were found showed the highest performance for these characteristics at both T0 and T1 nitrogen levels. These identified lines would be further used in development of nitrogen use efficient wheat varieties, which will greatly facilitate the resource poor farmers to enhance the productivity.