Genetic variability of Mg, Ca, and K in crested wheatgrass

Mayland, H.F. and Asay, K.H. (1989) Genetic variability of Mg, Ca, and K in crested wheatgrass. Journal of Range Management. 41(2):109-113.

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Abstract

Increasing available Mg in crested wheatgrass (Agropyron spp.)
could reduce the incidence of grass tetany (hypomagnesemia) in
ruminants glazing this forage. Raising the Mg levels might be done
through genetic processes if enough variation in ion concentration
existed in the Agropyrons. The purpose of this study was to determine
the genetic variation in Mg, Ca, and K concentrations in 2
crested wheatgrass populations. Parent plants were vegetatively
propagated to provide 6 replicates each of 12 clones of crested
wheatgrass (A. desertorum) and 16 F3 clones of colchicine-induced
tetraploid A. cristatum X natural tetraploid A. desertorum. Each
plant was selected on a basis of seedling and mature plant vigor,
forage, and seed yield, leafiness, resistance to pests, and response to
environmental stress. The 2 populations were grown in separate,
space-planted nurseries at Logan, Utah. Herbage was harvested at
the pre-boot and early flowering stage in each of 2 years. Magnesium
and Ca were determined by atomic absorption and K by
flame emission. A reduced tetany potential (RTP) index for each
clone was calculated as the sum of normalized Mg and (Ca+Mg)/K
values. Significant (P<0.01) differences for all traits were detected
among clones in each population. All traits, except K and RTP,
were closely correlated. Broad-sense heritability values for most
traits ranged from 0.61 to 0.84. Enough genotypic variation existed
in both populations to warrant breeding lines with higher concentrations
of Mg and larger RTP values. Such changes could reduce
the incidence of grass tetany in livestock grazing crested wheatgrass.

Item Type:	Article
NWISRL Publication Number:	0674
Subjects:	Irrigated crops > Grass forage > Chemistry Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:53
Last Modified:	05 Jan 2017 19:01
Item ID:	511
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/511