Efficacy evaluation of some fumigants against Fusarium oxysporum and enhancement of tomato growth as elicitor-induced defense responses

Abstract

Fusarium wilt, the most serious soil-borne pathogen, is a serious problem for tomato production worldwide. The presented study evaluated the antifungal activity against Fusarium oxysporum f. sp. lycopersici in vitro and in vivo for nine fumigants. In addition, the research examined the possibility of enhancing the growth of tomato plants in order to increase resistance against this disease by using four chemical inducers. The results indicated that at 20 mg/L, the radial growth of the pathogen was inhibited 100% by formaldehyde and > 80% by phosphine. Among the essential oils investigated, neem oil was the most effective, however, it only achieved 40.54% at 500 mg/L. The values of EC50 for all fumigants, except dimethyl disulfide (DMDS) and carbon disulfide (CS2), were lower than those for thiophanate-methyl. Phosphine was the highest efficient. The elicitors can be arranged based on their effectiveness, gibberellic acid (GA3) > sorbic acid > cytokinin (6-benzylaminopurine) > indole-3-butyric acid. The change in root length, fresh weight, and dry weight was greater with soil drench than with foliar application. The fumigant generators formaldehyde, phosphine and 1,4-dichlorobenzene and bio-fumigants citrus and neem oils as well as elicitors gibberellic and sorbic acid could be one of the promising alternatives to methyl bromide against Fusarium oxysporum as an important component of integrated management of Fusarium wilt.

A standard area diagram for Fusarium yellows rating in sugar beet (Beta vulgaris L.)

“…However, because BvFus-SAD-v2 used an expanded the image library, has categorical images at 10% intervals, we recommend the use of BvFus-SAD-v2 for Fusarium yellows screening (grayscale version SI Figure 2). While we did not test the effect of pre-training human raters to gain experience in Fusarium yellows symptomology before assessing disease score, there is evidence to suggest that familiarity with the specific disease symptomology does significantly improve accuracy and precision of ratings (Franceschi et al, 2020, Bock et al, 2009, Yadav et al, 2013. Additionally, it should be understood that due to the overestimation generally caused by BvFus-SAD-v1, use of the BvFus-SAD-v1 in breeding programs may cause accidental culling of resistant germplasm.…”

“…Participant rated values were "estimated" values. Data analysis was conducted using R version 4.2.0 and modified scripts from Franceschi et al (2020).…”

“…SADs aid workers of various experiential background in the field when assessing plant damage ranging from wholeplant to single leaf symptoms (Vereijssen et al, 2003). Properly designed SADs have been shown to produce accurate and precise measures of disease when compared to the true disease score (Franceschi et al, 2020, Moreira et al, 2019. Notably, a SAD does not currently exist in sugar beet for Fusarium-induced diseases, therefore the aims of this study were to (1) develop a practical, useful and uniform standard area diagram for Fusarium yellows rating on sugar beet using expert raters as "trued" values, and to (2) assess the possibility of applying quick imaging and naïve bayes pixel quantification and imaging as a high throughput, equally accurate method for rating Fusarium-induced diseases.…”

“…In sugar beet, F. oxysporum forma specialis betae (FOB) strain F19 causes Fusarium yellows and in susceptible plants can causing wilting, chlorosis of the leaves, stunting, and plant death (Hanson et al, 2009). Because soil-borne fungi are difficult to control with chemical fungicides, a major line of defense against Fusarium yellows in beet is resistant cultivars (El-Aswad et al, 2023). A limited number of sugar beet germplasm with improved resistance to Fusarium yellows has been developed by USDA-ARS pre-breeding programs (Panella et al, 2015, Todd et al, 2023), which have utilized wild germplasm from the USDA National Plant Germplasm System for Fusarium resistance trait discovery and introgression.…”

Design and Synthesis of Eugenol Derivatives Bearing a 1,2,3-Triazole Moiety for Papaya Protection against Colletotrichum gloeosporioides

“…Furthermore, the emergence of pathogen resistance necessitates the exploration of novel, more efficient, and environmentally friendly compounds. 11,12 In light of these challenges, our research group has focused on developing efficient fungicides using molecular hybridization, a widely explored strategy for the pursuit of bioactive compounds. 13,14 This technique involves combining two bioactive molecules, such as 1,2,3-triazole and eugenol, to enhance the fungicidal activity of the resulting hybrid compounds.…”