Alteration of plant species mixtures by virus infection: Managed pastures the forgotten dimension

Abstract

Virus infection occurs frequently in plant populations consisting of species mixtures. These populations include mixed cropping situations, such as subsistence agriculture, market gardens and larger scale production, intercropping systems, and both unmanaged and managed

Tolerance of plant virus disease: Its genetic, physiological, and epidemiological significance

“…The impact of viruses on species composition in managed mixed species pastures depends on the fitness of individual plant species (Jones, 2022), their ability to grow, set seed, and persist in the pasture. In this, tolerance will play a major role: a plant species weakened by virus infection may not be able to compete with a virus‐tolerant species, virus may spread from a tolerant species to a susceptible or less tolerant species causing decline, or there is no impact due to mild symptoms or asymptomatic infection across all species in the pasture, as shown schematically in Figures 4 and 5.…”

“…Schematic illustration of growth outcomes where virus infection was present in three or more plant species mixtures (Jones, 2022, Figure 5, re‐used under creative commons attribution licence, with legend modified from the original). (a) a virus‐infected, sensitive, susceptible host species (SH) is suppressed by competition with two nonhost species (NH'S) and a partially virus‐resistant host species (PRH).…”

Species of aphids found in ornamental and wild plants in Pagar Alam District, South Sumatra, Indonesia

“…Aphids suck phloem sap of tender plant parts, which can deplete essential nutrients for healthy growth (Cao et al 2018). Moreover, vector species can further weaken and stunt the growth of infected plants (Jones 2022). In addition, the honeydew that aphids secrete can lead to the growth of sooty mold, a black fungus that can prevent sunlight from reaching the plant's leaves, thereby impairing photosynthesis, the process by which plants produce food (Singh and Singh 2021).…”

Australian Cool-Season Pulse Seed-Borne Virus Research: 1. Alfalfa and Cucumber Mosaic Viruses and Less Important Viruses

“…Furthermore, compared with pulses, pasture legume species are commonly present for longer periods during the annual growing season and, in some cases, are perennials. They, therefore, constitute an important virus reservoir for the spread of legume viruses into pulse crops [18,27,[43][44][45][46][47]).…”

“…Also, a recent review entitled 'enhancing biosecurity against virus disease threats to Australian grain crops: current situation and future prospects' provided details of current pulse crop biosecurity threats [25]. Furthermore, several reviews described past Australian pasture legume research: (i) general Australian pasture pathogen disease reviews included summaries of virus disease studies up to when they were published [53][54][55][56][57]); (ii) a more detailed review of research on subterranean clover (Trifolium subterraneum) virus diseases up until the year 1986 [58]; (iii) three reviews focused on findings with virus diseases of annual and perennial pasture legumes up until the year 2012 [43,45,46]; and (iv) a more recent review included Australian research about alterations to the species balance arising from virus infection of managed pastures mostly sown with pasture legume and/or grass species mixtures [47]. However, a comprehensive review of Australian seed-borne pulse virus disease research since the 1950s, like that recently published for virus diseases of oilseeds and cereals [24], is lacking despite the considerable volume of research performed on this subject over the last seven decades.…”