Infection of susceptible/tolerant barley genotypes with Barley yellow dwarf virus alters the host plant preference of Rhopalosiphum padi clones depending upon their ability to transmit BYDV

Abstract

Discovering mechanisms of plant–virus–vector interactions is fundamental to understand their ecology and evolution and to apply this knowledge in plant protection. To study the influence of varying Barley yellow dwarf virus (BYDV) transmission efficiencies on host plant preference of Rhopalosiphum padi (L.) clones, we performed host choice experiments with two barley cultivars (BYDV susceptible cv. ‘Rubina’ and BYDV tolerant cv. ‘Vixen’) including healthy and virus-infected plants. For the susceptible barley cultivar ‘Rubina’, aphid clone R07 (high transmission efficiency) preferred BYDV-infected over healthy host plants after 24 h, while clones D10 (medium transmission efficiency) and R09 (low transmission efficiency) preferred neither host. In contrast, BYDV infection of ‘Vixen’ did not affect the plant’s appeal for aphid clone R07. Host plant access, indicated by ingestion and observed by electrical penetration graph technique for a period of 2 h, was facilitated on BYDV-infected cv. ‘Rubina’ for the clones R07 and D10, whereas an opposite effect was observed for the clone R09. For R07 and R09, the difference was not visible after a period of 5 h. As observed earlier for BYDV-infected wheat, enhanced emission of volatile organic compounds associated with virus-induced attraction was detected for BYDV-infected cv. ‘Rubina.’ It is concluded that host plant preference is possibly linked with a high BYDV transmission efficiency as observed for the clone R07, leading to a fitness advantage of this clone as indicated by early increased ingestion. This advantage is not present on BYDV-tolerant genotypes most likely due to the absence of infection symptoms.

Virus-Induced Plant Volatiles Promote Virus Acquisition and Transmission by Insect Vectors

“…The interactions among host plants, plant viruses, and insect vectors are multiple and complex [ 3 , 27 , 28 ]. Plant virus infection could alter chemical cues and behavioral changes in its host plants and insect vectors that enhance virus epidemic and dispersal [ 4 , 10 , 29 , 30 ].…”

Sugar beet resistance to green peach aphid Myzus persicae (Sulzer) and black bean aphid Aphis fabae (Scop.): Mechanisms and Implications for breeding

“…However, further investigation is needed to understand the potential adaptation of M. persicae to this mechanism. Since a virus infection could be used as a putative tool by aphids to increase the accessibility of genotypes, as suggested by Kern et al (2022) for BYDV and Rhopalosiphum padi, the absence of such an effect in some of the tested lines seems to be a trait for plant breeding. This mechanism therefore also needs to be investigated in detail.…”

“…To verify BYV infection of host plants, a total of 50 mg leaf material was randomly sampled from each plant and a DAS-ELISA was performed for each plant for BYV infection. For the detection of infected plants, a threshold was calculated based on the mean of negative controls+3 * SD (σ) (Kern et al, 2022). Plants with extinction values below the threshold were regarded as negative.…”

High-resolution mapping ofRyd4Hb, a major resistance gene toBarley yellow dwarf virusfromHordeum bulbosum

“…Five to ten Rhopalosiphum padi aphids of the biotype R07, that were reared on BYDV-PAV1 Aschersleben (PAV1-ASL) infected plants as described by Kern et al (2022), were placed on each one-week-old seedlings to be phenotyped in an air-conditioned greenhouse (20 °C, 16 h photoperiod, 10 klx). The aphids were killed after two days using the insecticide Confidor ® WG 70 (Bayer CropScience AG, Germany).…”

“…Plants for EPG experiments were reared in a greenhouse and were used at a 3-4 leaf stage where aphids were placed on the lower side of the second leaf. Aphids were reared as described before (Kern et al, 2022). Aphids starved for 1 hour before they were placed on the leaf.…”