Similarities in Seed and Aphid Transmission Among Soybean mosaic virus Isolates

Abstract

Soybean mosaic virus (SMV) is an aphid- and seed-transmitted virus that infects soybean (Glycine max) plants and causes significant yield losses. Seed-borne infections are the primary sources of inoculum for SMV infections. The strain specificity of SMV transmission through seed and SMV-induced seed-coat mottling were investigated in field experiments. Six soybean plant introductions (PIs) were inoculated with eight SMV strains and isolates. Transmission of SMV through seed ranged from 0 to 43%, and isolate-by-soybean line interactions occurred in both transmission rates and percentages of mottled seeds. For example, SMV 746 was transmitted through 43% of seed in PI 229324, but was not transmitted through seed of PIs 68522, 68671, or 86449. In contrast, SMV 413 was transmitted through seed from all PIs. SMVs that were transmitted poorly by the Asian soybean aphid, Aphis glycines, also were transmitted poorly through seed. No predicted amino acid sequences within the helper-component protease or coat protein coding regions differentiated the two groups of SMV strains. The loss of aphid and seed transmissibility by repeated mechanical transmission suggests that constant selection pressure is needed to maintain the regions of the SMV genome controlling the two phenotypes from genetic drift and loss of function.

Fitness penalty in susceptible host is associated with virulence of Soybean mosaic virus on Rsv1‐genotype soybean: a consequence of perturbation of HC‐Pro and not P3

“…However, as shown in this article, a significant reduction in virus accumulation and disease symptom amelioration in susceptible soybean cultivars are associated with gain of virulence on Rsv1 . SMV is transmitted naturally by aphids and is also seed borne (Domier et al ., ). In other viral pathosystems, virus concentration in the source plant has been shown to influence vector transmission efficiency (Banik and Zitter, ; Gray et al ., ).…”

Soybean mosaic virus: a successful potyvirus with a wide distribution but restricted natural host range

“…Within CP, the DAG motif and an amino acid substitution near the putatively exposed carboxyl terminus of CP are important for seed transmission and virus‐induced seed coat mottling. The findings that SMV HC‐Pro and CP are involved in both aphid and seed transmission is supported by observations that SMV field isolates poorly transmitted by A. glycines are also poorly transmitted through seed (Domier et al ., ).…”

Effects of single and mixed infections of Bean pod mottle virus and Soybean mosaic virus on host‐plant chemistry and host–vector interactions

“…However, there are also ecological factors that might contribute to divergence from the expected pattern for particular plant virus systems, including those involving SMV. For example, the relatively high rate of seed transmission exhibited by this virus (Domier et al 2007) may make it less reliant on vector transmission and thereby reduce selection favouring effects on host-plant phenotypes that are conducive to efficient transmission by aphids. Furthermore, many non-persistently transmitted viruses, including SMV (Halbert, Irwin & Goodman 1981), can be effectively transmitted by non-colonizing aphid species, individuals of which may visit and probe non-host plants (and thereby acquire or transmit virions) but then disperse due to the general unsuitability of the host plant (Mauck et al 2010(Mauck et al , 2012.…”

“…This study focuses on single and dual infections by two viruses that frequently co-occur in US soyabean agroecosystems: Bean pod mottle virus (BPMV, Comoviridae), which is transmitted by chrysomelid beetles and by the coccinellid Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), and Soybean mosaic virus (SMV, Potyviridae), which is transmitted by aphids, and which can also be transmitted across generations via seeds (Domier et al 2007). Each of these pathogens has significant economic impacts in soyabean, with reported yield losses of up to 50% for BPMV (Hopkins & Mueller 1984) and 35% for SMV (Stuckey, Ghabrial & Reicosky 1982).…”