Wheat Streak Virus (WSMV) in Triticum aestivum: causes and effects on yield

Abstract

Wheat stripe virus, also called wheat stripe mosaic virus (WSMV), is transmitted by the mite Aceria tosichella. If the infection occurs early, it can affect plant size and grain filling. It has caused yield losses of up to 10% in wheat in Argentina. Objective. To evaluate the causes and effects of the virus on wheat (Triticum aestivum) yield. The experimental design and field sampling were randomized. Samples were taken from leaf samples of the algarrobo wheat cultivar. The sampling method was randomized, with the source being classified as having and not having the disease. The disease occurs under natural infections, and monitoring was carried out up to growth stage Z7. The trial was conducted in Junín, Buenos Aires, Argentina, between 2019 and 2021. Pairs of wheat plants with disease symptoms had lower yield (Y) values ​​in kg/ha with disease: 3511.11 A compared to the data for those without disease: 4450 B. The same was observed for thousand-grain weight (TGW) values ​​with disease: 30.56 A and without disease: 33.67 B; the number of grains in wheat (NG) with disease: 10751.11 A and without disease: 14997.22 B; and the SPAD units in the flag leaf of wheat with disease: 33.78 A and without disease: 47.5 B. The abbreviations A and B refer to the existence of significant differences. The mite Aceria tosichella acquires the virus by feeding on infected plants and then transmits it to healthy plants, while the virus survives in weeds and wheat stubble between plantings, acting as a green bridge for the mites. If the attack occurs early, the size of the plants and the filling of the grains are reduced. An early attack of the virus generates a reduction in the size of the plant and the filling of the grains in the ears, therefore, lower wheat yield.