Hulless Barley Response to Ethephon Application

Abstract

Ethephon [(2‐chloroethyl) phosponic acid] is commonly used in mid‐Atlantic barley production to reduce plant height and lodging, but is known to reduce grain yield and test weight in some barley cultivars. Management practices that produce high yield and good grain quality in traditional mid‐Atlantic winter barley have yet to be evaluated for hulless barley. This research examined response of three winter hulless barley genotypes to ethephon plant growth regulator (PGR) and provides recommendations for appropriate PGR rates. Ethephon applied at 2.5 oz a.i./acre resulted in decreased plant height (8.3 inches) and lodging index (1.2 units). With higher rates, a trend toward continued decreased height and lodging was seen even when differences were not significant. Grain yield was decreased by an average of 20 bu/acre in four of 15 site year‐genotype combinations. Grain test weight was increased in one instance but impacts of ethephon varied by genotype, which may warrant further study. Labeled rates of ethephon are appropriate for application to a range of hulless barley cultivars but rates above 2.5 oz a.i./acre should be avoided unless severe lodging is anticipated. Ethephon application should occur only when moisture and temperature are favorable for plant growth and not when the crop is under stress.

Trinexapac‐ethyl rate and timing impact on malt barley production in Virginia

“…The plant growth regulator (PGR) ethephon ([2chloroethyl] phosponic acid) has been shown to decrease plant height (Bulman & Smith, 1993) and lodging (Thomason, et al, 2007) of small grains in the Mid-Atlantic region of the United States, but negative impacts on grain yield and test weight have been reported on a cultivar-dependent basis with ethephon application as well (Taylor et al, 1991;Thomason, et al, 2007). Trinexapac-ethyl (TE) {ethyl 4-[cyclopropyl(hydroxyl)methylene]−3,5-dioxocyclohexane-1-carboxylate} is a PGR that has recently been labeled for small grain application in the United States.…”

The Role of Biorefinery Co-Products, Market Proximity and Feedstock Environmental Footprint in Meeting Biofuel Policy Goals for Winter Barley-to-Ethanol

“…The LCI includes addition of N, P, and K nutrients, and energy for field preparation and feedstock harvesting. Preharvest nutrient additions described by Thomason [46] specify a winter barley yield of 5380 kg ha −1 and application of fertilizers in the following proportions: nitrogen (N), preplant urea (12 kg N ha −1 ) and spring liquid urea ammonium nitrate (70 kg N ha −1 ); phosphate (P), diammonium phosphate (23 kg N ha −1 , 58 kg P ha −1 ); potassium, (52 kg K ha −1 ); and lime (0.74 metric tons ha −1 ). Lubricant, oil, and diesel fuel inputs are applied in preharvest (12.7 L diesel ha −1 ) and in harvest (16.9 L diesel ha −1 ) portions.…”

“…Data for constructing the life cycle inventory (LCI) model include crop production, transportation of the feedstock to the biorefinery, fuel conversion, transportation and distribution of denatured ethanol, and the combustive emissions for using the fuel. The LCI model was constructed using SimaPro 8.4 [45] with agronomic inputs specified by Thomason [46], nitrous oxide emissions and changes in soil organic carbon (SOC) generated using the DayCent model [47], process-guarantee data from a starch-based biorefinery completed in Hopewell, Virginia, in 2011, and vehicle in-use emissions from the GREET 1 model [48]. Uncertainty in the most sensitive parameter inputs were considered and integrated into the LCI model using Monte Carlo simulation.…”

Management of abiotic stress in barley (Hordeum vulgare L.)

“…So, restricted use can be done only under severe lodging scenario. Moreover, it should be use under congenial temperature and moisture scenario for plant growth not under stress environment (Thomason et al, 2007).…”