HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Herridge, D. F. Articles by Rose, I. A. Search for Related Content PubMed Articles by Herridge, D. F. Articles by Rose, I. A. Agricola Articles by Herridge, D. F. Articles by Rose, I. A.

Heritability and Repeatability of Enhanced N₂ Fixation in Early and Late Inbreeding Generations of Soybean

NSW Agriculture, RMB 944, Tamworth, N.S.W., Australia, 2340
NSW Agriculture, PMB Myall Vale, Narrabri, N.S.W., Australia 2390

^* Corresponding author.

Moderate to high levels of soil nitrate suppress nodulation and N₂ fixation in soybean [Glycine max (L.) Merr.], resulting in some instances in a net loss of N from the soil when the high-protein seed is harvested. Development of nitrate tolerance, i.e., the ability to nodulate and fix N₂ in the presence of soil nitrate, in cultivars of soybean is desirable. Our objectives were to (i) combine, through hybridization, the reported nitrate tolerance of Korean genotypes 464, 466, 468, and 469 (Commonwealth of Australia Plant Introduction nos CPI66126, CPI66141, CPI66157 and CPI66159, respectively) with the agronomic and seed traits of cultivars Valder, Reynolds, Forrest and Bossier; (ii) assess heritability and repeatability of N₂ fixation between individual F₂ plants and F₂-derived F₃ lines, and F₃-derived lines in the F₆ and F₇ generations; and (iii) examine correlations of N₂ fixation with agronomic and seed traits. Individual plants and lines were evaluated during five seasons between 1986–1987 and 1990–1991 on alkaline vertisol soils (Typic Pellustert) at Breeza and Narrabri, Australia, and in glasshouse culture at Narrabri. The xylem ureide technique was used to estimate N₂ fixation activity of individual F₂ plants, and of F₂-derived F₃ lines and F₃-derived F₆ and F₇ lines. Data from F₂ and F₃ generations showed that relative ureide-N values for the individual F₂ plants was of low heritability. We concluded that single-plant selection for N₂ fixation in the F₂ generation was largely ineffective. Data from F₆ and F₇ plot trials, however, indicated that repeatability on a plot basis for relative ureide-N was about 0.5 (P< 0.01). Phenotypic correlations between relative ureide-N in xylem sap and other plant and seed traits were variable and generally non-significant. The selection of site was vital for detecting enhanced N₂ fixation. Sites with low soil nitrate did not allow discrimination among genotypes. Three F₃-derived lines, D22-8, K78-1, and A46-4, which were identified in the F₆ and F₇ trials at the high-nitrate sites, had the N₂ fixation characteristics of the Korean parents and near-commercial yields (75–83% of that of the highest yielding cultivar, Forrest.

Received for publication November 10, 1992.

This article has been cited by other articles:

				E. T. Gwata, D. S. Wofford, K. J. Boote, A. R. Blount, and P. L. Pfahler Inheritance of Promiscuous Nodulation in Soybean Crop Sci., February 23, 2005; 45(2): 635 - 638. [Abstract] [Full Text] [PDF]

				L. C. Purcell, R. Serraj, T. R. Sinclair, and A. De Soybean N2 Fixation Estimates, Ureide Concentration, and Yield Responses to Drought Crop Sci., March 1, 2004; 44(2): 484 - 492. [Abstract] [Full Text] [PDF]