Annual Progress Report on Malting Barley Research March, 2002

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Methodology
1) Investigating the influence of silicon on plant regeneration
Identical experiments were conducted at Fargo, ND, and Aberdeen, ID. Following the
procedures described in Bregitzer et al. (2000), the plant regeneration response of callus
derived from immature embryos of three cultivars--Morex, Harrington, and Golden
Promise-- were measured in response to various levels of silicon supplementation (as
SiO2; control (0), 10, 100, 500, 1000, and 5000 :M Si for initial experiments). Data were
analyzed using the SAS procedure CATMOD.
2) Measuring somaclonal variation in plants derived from the original and improved
media
The experiments conducted last year (The effects of media improvements on newer
cultivars and advanced breeding lines, AMBA Prog. Rep. 2000) compared the
regeneration responses on our original and improved media. Four regenerated plantstwo
from the original media, two from the improved media--were grown to maturity from
eight cultivars or breeding lines: Colter, Crystal, Conlon, Baronesse, Morex, 90Ab321,
Drummond, and Golden Promise. Seed from these plants, and their respective single
plant-derived parental controls, was increased in New Zealand during their 2000-2001
growing season. The agronomic performance of these lines were evaluated in replicated
plots at two locations, Aberdeen (irrigated) and Tetonia, (dryland) ID. Standard smallplot
yield trials were conducted: 4 replicates at each location; 40 sq. ft. per plot; traits to
be measured include heading date, plant height, lodging percentage, grain yield, test
weight, and percentage plump kernels.
Results
Influence of silicon on plant regeneration
One of two planned experiments has been completed at each location, and the second
experiment is nearing completion. The Aberdeen data do not include Harrington because
of plant health problems in the growth chamber. Significant differences in plant
regeneration were found among cultivars, locations and silicon concentrations, but the
interaction between silicon concentration and cultivars was not significant.
The addition of silicon to the media increased green plant regeneration for all cultivars at
both locations. Overall, regeneration rates were highest when 500 :M Si was added to the
media, which induced, on average, more than double the number of regenerated plants
induced on medium lacking silicon. The amount of silicon in the media appeared to have
no effect on the number of albino plants regenerated.
A second set of experiments is underway at both locations, dropping the 10 and 5000 :M
Si concentrations. These experiments will confirm whether the 500 :M Si concentration
results in increased green plant regeneration.
Agronomic performance of regenerated plants
Two important differences between the "original" and "improved" media formulations
are the increased copper concentration and the addition of BAP. Previous agronomic