Genetic analyses of nitrogen assimilation enzymes in Brassica juncea (L.) Czern & Coss
Nitrogen (N) is a critical input for plant growth and development. A better understanding of N uptake and utilization is important to develop plant breeding strategies for improving nitrogen use efficiency (NUE). With that objective in mind, we assayed a SNP-genotyped association panel comprising 92 inbred lines for the activities of nitrate reductase (NR), nitrite reductase (NIR), glutamine synthetase (GS) and glutamate synthase (GOGAT). All these enzymes are associated with N assimilation. The experiments were carried out at two levels of N application: no added N (N0) and agrnomically recommened dose (100 kg/ha) of N application (N100). Genome wide association studies (GWAS) helped to identify several marker-trait associations (MTAs), involving chromosomes A01, A06, A08, B02, B04, B05 and B08. These explained high phenotypic variation (up to 32%). Annotation of the genomic region(s) in or around significant SNPs allowed prediction of genes encoding high affinity nitrate transporters, glutamine synthetase 1.3, myb-like transcription factor family protein, bidirectional amino acid transporter 1, auxin signaling F-box 3 and oxidoreductases. This is the first attempt to use GWAS for identification of enzyme QTLs to explain variation for nitrogen assimilation enzymes in Brassica juncea.
KeywordsIndian mustard Nitrogen use efficiency Nitrate reductase Genotyping by sequencing Association mapping
The studies were financially supported by the Department of Biotechnology, Government of India in the form of Centre of Excellence and Innovation in Biotechnology “Germplasm enhancement for crop architecture and defensive traits in Brassica juncea L. Czern. and Coss”. SSB also acknowledges salary support from Indian Council of Agricultural Research under ICAR National Professor Chair.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 1.Goel P, Sharma NK, Bhuria M, Sharma V, Chauhan R, Pathania S, Swarnkar MK, Chawla V, Acharya V, Shankar R, Singh AK (2018) Transcriptome and co-expression network analyses identify key genes regulating nitrogen use efficiency in Brassica juncea L. Sci Rep 8:7451CrossRefPubMedPubMedCentralGoogle Scholar
- 12.Gupta S, Atwal AK, Kumar H, Sardana V, Sangha MK, Kumar N, Banga SS (2013) Characterizing oilseed Brassica germplasm for traits associated with nitrogen use efficiency using biplot analysis. Crop Improv 40:34–43Google Scholar
- 14.Kouadiao JY, Kouakou HT, Kone M, Zouzou M, Anno PA (2007) Optimum conditions for cotton nitrate reductase extraction and activity measurement. Afr J Biotechnol 6:923–928Google Scholar
- 26.Zhang N, Gibon Y, Wallace JG, Lepak N, Li P, Dedow L, Chen C, So YS, Kremling K, Bradbury PJ, Brutnell T, Stitt M, Buckler ES (2015) Genome-wide association of carbon and nitrogen metabolism in the maize nested association mapping population. Plant Physiol 168:575–583CrossRefPubMedPubMedCentralGoogle Scholar
- 31.Wei X (2011) Genome-wide association analysis and phenotypic study of nitrogen use efficiency in Arabidopsis thaliana. Master Thesis, Plant Genetics, Wageningen University, Wageningen, The NetherlandsGoogle Scholar
- 34.Sinha SK, Sevanthi VAM, Chaudhary S, Tyagi P, Venkadesan SK, Rani M, Mandal PK (2018) Transcriptome analysis of two rice varieties contrasting for nitrogen use efficiency under chronic nitrogen starvation reveals differences in chloroplast and starch metabolism-related genes. Genes 9:206CrossRefPubMedCentralGoogle Scholar
- 41.Doyle JJ, Doyle JL (1990) Isolation of plant DNA from fresh tissue. Focus 12:13–15Google Scholar
- 42.Duitama J, Quintero JC, Cruz DF, Quintero C, Hubmann G, Foulquie-Moreno MR, Verstrepen KJ, Thevelein JM, Tohme J (2014) An integrated framework for discovery and genotyping of genomic variants from high-throughput sequencing experiments. Nucleic Acids Res 42(6):e44. https://doi.org/10.1093/nar/gkt1381 CrossRefPubMedPubMedCentralGoogle Scholar
- 50.Malagoli P, Laine P, Rossato L, Ourry A (2005) Dynamics of nitrogen uptake and mobilization in field-grown winter oilseed rape (Brassica napus) from stem extension to harvest. I. Global N flows between vegetative and reproductive tissues in relation to leaf fall and their residual N. Ann Bot 95:853–861CrossRefPubMedPubMedCentralGoogle Scholar
- 51.Malagoli P, Laine P, Rossato L, Ourry A (2005) Dynamics of nitrogen uptake and mobilization in field-grown winter oilseed rape (Brassica napus) from stem extension to harvest. II. An 15N-labelling-based simulation model of N partitioning between vegetative and reproductive tissues. Ann Bot 95:1187–1198CrossRefPubMedPubMedCentralGoogle Scholar
- 58.Shangguan ZP (2007) Effects of nitrogen application rate on nitrate reductase activity, nitric oxide content and gas exchange in winter wheat leaves. Chin J Appl Ecol 18:1447–1452Google Scholar