Abstract
Potato (Solanum tuberosum L.) Fusarium wilt is an increasingly serious disease in many potato-growing regions worldwide and notably in Tunisia. Fusarium sambucinum, F. oxysporum, F. solani, and F. graminearum are the main causal agents with F. oxysporum being the most aggressive on plants. Co-infection with this Fusarium species complex is frequently observed. Cultivar responses to different pathogen mixtures can give additional information on the relative aggressiveness of the different complexes. This study may lead to a better understanding of how interactions between the four Fusarium species may affect disease incidence and severity. Interactions between these Fusarium species was evaluated using single and combined inoculations (15 different Fusraium inocula) onto potato the two cultivars Spunta and Oceania. The tested inocula were evaluated for their effects on leaf yellowing and necrosis, vascular discoloration severity, potato growth and production. Necrosis severity noted 75 days post-planting induced by three different inocula C2-1 (F. sambucinum + F. solani), C2-2 (F. solani + F. oxysporum), and C3-3 (F. sambuinum+F. oxysporum +F. graminearum) were found to be the highly aggressive inoculation treatments. Overall, all mixed inocula including F. sambucinum showed increased aggressiveness levels. The two cultivars exhibited differential response to the different tested Fusarium mixtures and behaved in the majority as sensitive to moderately sensitive to C1-1, C1- 4, C2-1, C2-2, C2-3, C2-4, C2-5, C2-6, C3-1, C3-3, C3-4 and C4 treatments. This study clearly demonstrated that Fusarium wilt of potato is expected to be more severe when more than one Fusarium species is present. The relative predominance of F. sambucinum may reflect its competitive potential in mixture and its significant involvement in potato Fusarium wilt severity.
Highlights
Potato (Solanum tuberosum L.) losses attributed to fungal diseases are becoming the major worrying constraints faced by potato growers worldwide
The relative predominance of F. sambucinum may reflect its competitive potential in mixture and its significant involvement in potato Fusarium wilt severity
In the current investigation, we studied the interaction that can occur between different Fusarium species colonizing the same ecological niche where a specific interaction leads to the predominance of some species over others
Summary
Potato (Solanum tuberosum L.) losses attributed to fungal diseases are becoming the major worrying constraints faced by potato growers worldwide. Many potato organs (tubers, roots, stems, etc) may be infected by Fusarium species leading to root and tuber rots and eventual plant wilt witling in addition to tuber contamination by mycotoxins (Pernezny et al, 2014). Fusarium wilt diseases rank among the most devastating diseases, constituting a significant agricultural threat (Fisher et al, 2012) This problem persists throughout the world and is prevalent in the most potato-growing areas leading to 30-50% yield losses and decreased quality and safety of tubers intended for consumption (Ommati and Sharifi, 2008; Kerkeni et al, 2013). Infection of plants may be initiated on roots through natural openings or wounds before invading the xylem vascular tissues This infection process leads to plant stunting, reduced growth, leaf yellowing, vascular browning, and eventual total wilting of severely infected stems (Ayed et al, 2006). In the same way, Dung et al (2013) indicated that co-infection by Pectobacterium and V. dahliae can result in increased potato early dying severity
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
