ARS | Publication request: Barley yellow dwarf virus effects on cereal plant growth and transpiration

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 14, 2012
Publication Date: November 7, 2012
Citation: Erion, G.G., Riedell, W.E. 2012. Barley yellow dwarf virus effects on cereal plant growth and transpiration. Crop Science. 52:2794-2799. DOI: 10.2135/cropsci2012.0138.

Interpretive Summary: Barley yellow dwarf, the most widespread viral disease in cereal plants, causes an 11 to 33 percent reduction in yield in infected plants. The virus is transmitted from plant to plant during feeding by aphid insects. The virus damages the plant's vascular system and restricts sugar movement from the leaves to the rest of the plant. As roots are farthest from the leaves, the lack of effective sugar movement causes dramatically-reduced root growth. Although the effects of virus infection on roots are more rapid and severe than on the shoots, little is known about how virus infection affects the relationships between root and shoot growth. Even less is known about how changes in root system characteristics caused by virus infection affect root system function. Thus the objective of this experiment was to analyze effects of virus infection on plant growth and water movement through oat and barley plants. Virus infection decreased root dry weight, leaf blade size, and water movement through the plant in both plant species, but to a greater extent in oats than barley. Shoot dry weight and leaf blade dry weights were reduced by virus infection only in oats. Decreased water movement through cereal plants was strongly associated with decreased leaf blade area. Information derived from this experiment may be useful in breeding plants that tolerate or resist virus infection or in developing crop management strategies that ameliorate yield loss caused by this disease-causing virus.

Technical Abstract: Little is known about how changes in root system biomass caused by barley yellow dwarf virus (BYDV) infection impact water relations in cereal plants. Objectives of these greenhouse studies were to elucidate virus infection effects on plant growth and apparent transpiration rate in oats (Avena sativa L. 'Coast Black’) and barley (Hordeum vulgare L. ‘Robust’). Seedlings grown in plastic pots were infested at the first leaf stage (13 days after planting) with viruliferous (BYDV, PAV strain) or non-viruliferous bird cherry oat aphids (Rhopalosiphum padi L.) for 48 h. Aphids were removed and plants grown for an additional 26 d. Root and shoot dry weight, root-to-shoot weight ratio, leaf blade dry weight, leaf blade area, and apparent transpiration rate (measured gravimetrically) were measured. Two repetitions of the experiment were conducted. Data were subjected to ANOVA and regression analysis. Viral disease symptoms, such as reduced tillers number, stunting, leaf chlorosis, and reddening, were more pronounced in oats than barley. Virus infection decreased root dry weight, root-to-shoot ratio, leaf blade area, and apparent transpiration in both species, but to a greater extent in oats than barley. Shoot dry weight and leaf blade dry weights were reduced by BYDV infection only in oats. Regression analysis revealed strong coefficients of determination between leaf blade area and root dry weight (r2=0.77) as well as between leaf blade area and apparent transpiration rate (r2=0.69). Thus BYDV treatment significantly decreased apparent transpiration rate in cereal plants and that this decrease was strongly associated with decreased leaf blade area.