Interaction between Cowpea Aphid-Borne Mosaic Virus Isolates and Its Effect on Passion Fruit Woodiness Disease on Passiflora edulis Sims and Passiflora ligularis Juss

Lucy J Kiptui,Faith J Toroitich,Dora C Kilalo,Meshack Obonyo,Gábor Kocsy

doi:10.1155/2020/8876498

Lucy J Kiptui, Faith J Toroitich + Show 3 more

Open Access

https://doi.org/10.1155/2020/8876498

Copy DOI

Abstract

In East Africa, passion fruit woodiness disease is caused by potyviruses, among which are Cowpea Aphid-Borne Mosaic Virus (CABMV) and Uganda Passiflora Virus (UPV). Previous studies suggest that synergistic interaction of viruses causes mild or severe outcomes of the disease. However, mixed infections of these viruses have not been documented. The aim of this study was to determine the effects of the interaction between two CABMV isolates causing passion fruit woodiness disease in Kenya. Healthy plants were mechanically inoculated at six-leaf stage. Four treatments were used: CABMV isolate 1, CABMV isolate 2, mixture of the two isolates, and noninoculated control. The test plants were maintained in a screen house, and data on symptom severity and rate of disease development were recorded. ELISA test was conducted to confirm virus presence and distribution. The results indicate that the CABMV isolates used are systemic. There were various differences in disease progression, which was faster in the sweet passion variety than in the purple variety. However, the latter had a higher disease severity. Coinfected plants expressed severe symptoms compared to the singly infected ones, indicating synergistic interaction between the viral isolates. This implies that coinfection has adverse impact resulting in higher economic losses.

Highlights

Passion fruit is an economical viable crop, grown in Kenya, to improve livelihoods of small holder farmers.e crop is among the top three exported fruits
Virus pathogens responsible for woodiness disease include Cowpea AphidBorne Mosaic Virus (CABMV), Passion Fruit Woodiness Virus (PWV), and Uganda Passiflora Virus (UPV) [5, 6]
It had earlier been assumed that the variation of disease symptoms observed was due to a different novel potyvirus, like UPV, but sequencing work done on woodiness virus isolates in Kenya by Kilalo (2012, unpublished) indicated the presence of CABMV only in the passion plants showing different symptoms. us, there is an assumption that several CABMV isolates or strains could exist in the country

Summary

Introduction

Passion fruit is an economical viable crop, grown in Kenya, to improve livelihoods of small holder farmers.e crop is among the top three exported fruits. It had earlier been assumed that the variation of disease symptoms observed was due to a different novel potyvirus, like UPV, but sequencing work done on woodiness virus isolates in Kenya by Kilalo (2012, unpublished) indicated the presence of CABMV only in the passion plants showing different symptoms. E interest of this research was to test the effects of interaction between two CABMV isolates that cause woodiness disease in Kenya on type of symptoms induced and symptom severity.

Results

Conclusion