Elucidating the Effect of Nutritional Imbalances of N and K on the Infection of Verticillium dahliae in Olive

Abstract

The effect of mineral nutrition on wilt diseases has been previously reported in many herbaceous hosts, though such an effect on Verticillium wilt in olive (Olea europaea L.; VWO), caused by Verticillium dahliae, is still uncertain. Field observations reveal that nitrogen (N) excess or imbalances of N-potassium (K) favour VWO epidemics. However, this has yet to be demonstrated. Thus, the aim of this study was to evaluate the influences of nutritional imbalances of N and K in V. dahliae infection of olive. To this end, adjusted treatments with N excess (↑N+↑Na), K deficiency (↓K) and their combination (↑N+↑Na+↓K) were evaluated on the viability of V. dahliae microsclerotia (MS), as well as on disease development in olive plants. In parallel, the potential indirect effect of the treatments on the viability of conidia and MS of V. dahliae was evaluated through the stimuli of root exudates. Treatments ↑N+↑Na and ↑N+↑Na+↓K decreased MS germination and disease progress, whereas ↓K significantly increased both parameters. Root exudates from treated plants increased the conidia germination of V. dahliae but reduced the MS germination. The results of this study will be the basis for planning further research towards a better understanding of the effect of mineral nutrition on VWO.

Streptomyces spp. Strains as Potential Biological Control Agents against Verticillium Wilt of Olive

“…The V. dahliae isolates V323 (D pathotype) [40] and V004 (ND pathotype) [41] were used for this study. These isolates are maintained in the fungal collection of the Department of Agronomy at the University of Cordoba (UCO, Córdoba, Spain).…”

Innovations towards sustainable olive crop management: a new dawn by precision agriculture including endo-therapy

“…Together with the fact that efficient strategies to reduce the disease index or control the pathogen dispersal are scarce ( López-Moral et al., 2022 ), it can be assumed that olive growers are going to face V. dahliae -caused issues more sharply in the future. Recent biological studies start shedding light into the nutritional imbalances upon V. dahliae infection in olives, where potassium deficiency was found to increase the olive wilt disease progress ( López-Moral et al., 2022 ). This study is laying the foundation for further much needed work to help generation integrated pest management programs that may also include dedicated mineral nutrient management.…”

“…This study is laying the foundation for further much needed work to help generation integrated pest management programs that may also include dedicated mineral nutrient management. Similarly, recent trials with foliar and root application phosphonate salt copper phosphite (CuPh), which stimulates plant immunity and has antimicrobial properties, show some potential in olive trees ( López-Moral et al., 2022 ). Other strategies for V. dahliae control currently being evaluated in olives are the application of beneficial microbes including Aureobasidium pullulans AP08 and Bacillus amyloliquefaciens PAB-024 ( López-Moral et al., 2022 ).…”

“…Similarly, recent trials with foliar and root application phosphonate salt copper phosphite (CuPh), which stimulates plant immunity and has antimicrobial properties, show some potential in olive trees ( López-Moral et al., 2022 ). Other strategies for V. dahliae control currently being evaluated in olives are the application of beneficial microbes including Aureobasidium pullulans AP08 and Bacillus amyloliquefaciens PAB-024 ( López-Moral et al., 2022 ). Being a vascular pathogen, more targeted alternatives of foliar or drench application of crop protection products are naturally in the spotlight of Verticillium wilt research.…”

Effect of Previous Crops and Soil Physicochemical Properties on the Population of Verticillium dahliae in the Iberian Peninsula

“…On the other hand, Ca and Mg, two of the most influential elements in the CEC, are believed to play a key role in disease resistance as they aid in cell wall formation, increasing its resistance to attack by numerous enzymes and preventing pathogen penetration, as reported by Pennypacker (1989) [ 10 ]. Regarding this matter, recent research showed that, in the case of olive plants, treatments with N and Na excess, and with N and Na excess and K deficiency, decreased the germination of the fungus MS and the disease progress after artificial inoculations [ 11 ]. Soil texture also appears to have a variable effect on the pathogen, probably due to the complexity of existing interactions [ 1 ].…”