Winter wheat (Triticum aestivum) response to Barley yellow dwarf virus at various nitrogen application rates in the presence and absence of its aphid vector, Rhopalosiphum padi

Abstract

Barley yellow dwarf (BYD) is one of the most common diseases of cereal crops, caused by the phloem‐limited, cereal aphid‐borne Barley yellow dwarf virus (BYDV) (Luteoviridae). Delayed planting and controlling aphid vector numbers with insecticides have been the primary approaches to manage BYD. There is limited research on nitrogen (N) application effects on plant growth, N status, and water use in the BYDV pathosystem in the absence of aphid control. Such information will be essential in developing a post‐infection management plan for BYDV‐infected cereals. Through a greenhouse study, we assessed whether manipulation of N supply to BYDV‐infected winter wheat, Triticum aestivum L. (Poaceae), in the presence or absence of the aphid vector Rhopalosiphum padi L. (Hemiptera: Aphididae), could improve N and/or water uptake, and subsequently promote plant growth. Similar responses of shoot biomass and of water and N use efficiencies to various N application rates were observed in both BYDV‐infected and non‐infected plants, suggesting that winter wheat plants with only BYDV infection may be capable of outgrowing infection by the virus. Plants, which simultaneously hosted aphids and BYDV, suffered more severe symptoms and possessed higher virus loads than those infected with BYDV only. Moreover, in plants hosting both BYDV and aphids, aphid pressure was positively associated with N concentration within plant tissue, suggesting that N application and N concentration within foliar tissue may alter BYDV replication indirectly through their influence on aphid reproduction. Even though shoot biomass, tissue N concentration, and water use efficiency increased in response to increased N application, decision‐making on N fertilization to plants hosting both BYDV and aphids should take into consideration the potential of aphid outbreak and/or the possibility of reduced plant resilience to environmental stresses due to decreased root growth.

How does vector diversity influence the transmission efficiency of yellow dwarf virus? Perspectives from a review

“…Viral particles reduce meristematic activity in the vascular tissue of infected plants (Esau, 1957), which can disrupt differentiation and development of cellular organelles in infected phloem cells (Jensen, 1969), resulting in stunted growth and eventual necrosis of infected cells (Esau, 1957), culminating in the symptoms detailed in Table 1. Persistent infestation with virus‐carrying vectors can increase the severity of disease observed (Liang et al., 2019).…”

Research Article The supply of nitrogen fertilizer in wheat to the highest environmental quality with satisfactory yield

“…Mantai et al (2015) observed in oats, growth in the biomass rate with the increase of doses of N-fertilizer in a single dose in the growing systems, a condition not always accompanied by the higher grain yield, results also verified in this research. In wheat, Liang et al (2019) found that the increase in nitrogen concentration in plant tissue significantly increased the biomass rate by applying the nutrient in a single dose. Research has indicated that the fractional supply of nitrogen can further decrease nutrient losses at the most propitious times for fertilization, improving the efficiency of the nutrient (Benin et al, 2012;Ferrari et al, 2016).…”

Yield Losses Caused by Barley Yellow Dwarf Virus-PAV Infection in Wheat and Barley: A Three-Year Field Study in South-Eastern Australia

“…While describing BYDV in 1953, Oswald and Houston [ 11 ] noted that damage caused by BYDV infection was particularly severe in a drought year, and others have also reported more severe yield losses from BYDV infection in years of lower rainfall [ 15 , 25 , 38 , 39 ]. Given that the root system of a plant infected with BYDV is also often just as stunted, and sometimes even more so, than the visible, above-ground portion of the plant [ 11 , 40 , 41 , 42 , 43 ], it has been suggested that the roots of infected plants may be too shallow to reach or obtain adequate water and nutrients in dry conditions [ 11 ]. This is one possible explanation for the especially severe yield losses observed in experiment 1, as 2015 was the second year in a row of well below average rainfall in the region ( Table 1 ).…”