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Verticillium wilt, caused by the soil-borne fungus Verticillium dahliae Kleb., poses a significant threat to olive (Olea europaea L.) cultivation worldwide. This review provides an in-depth comprehension of the disease and its management strategies. The genetic diversity of V. dahliae, comprising various pathotypes and races, has implications for virulence and host interactions. The fungus can affect a wide host range, including crops and trees. V. dahliae is responsible for many symptoms such as wilting, yellowing, stunted growth, necrosis, and vascular discoloration. Economic consequences caused by this pathogen include yield losses, low-quality olive oil, market restrictions, and increased production costs. Verticillium wilt thrives in warm temperatures and excessive soil moisture. Chemical and biological controls and cultural practices are evaluated as potential measures. However, the search for resistant cultivars stands out as a significant solution. Insights from this review underscore the need for an interdisciplinary approach to managing the Verticillium wilt of olives. Integrated disease management strategies, resistant cultivars, and sustainable practices emerge as pivotal approaches for disease control. [ABSTRACT FROM AUTHOR]

Botrytis cinerea, a causal agent of gray mold disease, is one of the most destructive fungal pathogens that leads to substantial global economic crop losses, especially for tomato plants. The present study aims to investigate the inhibitory effect of two microbial culture filtrates (BCA filtrate alone and combined with salicylic acid) of Trichoderma longibrachiatum and Pseudomonas sp. against the phytopathogenic fungus B. cinerea on tomato plants. The biochemical modifications, gray mold disease incidence, and fruit quality parameters of the tomatoes were determined according to tested treatments. The results showed that both fungi and bacteria were able to solubilize phosphate and produce IAA and HCN. T. longibrachiatum could produce hydrolytic enzymes (chitinase, protease, and glucanase). Otherwise, Pseudomonas sp. showed the capacity to produce catalase and amylase enzymes. Both microbial culture filtrates inhibited the hyphae growth of B. cinerea. The biocontrol efficacy, in vitro, was significant: up to 50% in terms of the growth inhibition rate at a concentration of 40%. The tomato seedlings' growth was promoted by the separate preventive treatments of each micro-organism culture filtrate. In addition, disease severity in the tomato seedlings and fruit was significantly reduced. Furthermore, the combined treatment of tomato fruit with culture filtrates and salicylic acid induced significant biochemical and physiological changes in fruit firmness, juice yield, total protein, and ROS enzyme activities. The culture filtrates of T. longibrachiatum and Pseudomonas sp. can be recommended as an effective microbial biofungicide to control gray mold disease under storage conditions. [ABSTRACT FROM AUTHOR]

The nematicidal potential of five filamentous fungi as biological control agents (BCAs) against the root-knot nematode (RKN), Meloidogyne javanica, infecting tomato was assessed in vitro and in pot experiments. The five promising native taxa, namely Trichoderma longibrachiatum, T. harzainum, T. asperellum, Lecanicillium spp., and Metacordyceps chlamydosporia, were selected to compare their effectiveness against both chemical (Mocap, 10% ethoprophos) and biological (abamectin) nematicides on M. javanica reproduction indices and plant growth parameters. The stimulation of defense mechanisms was assessed by monitoring changes in the enzymatic activities of the polyphenol oxidase (PPO), peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), lipid peroxidation (MDA), phenols, and proteins content of tomato roots. The laboratory assays revealed that T. longibrachiatum, M. chlamydoporia, and Lecanicillium spp. seemed to be the most effective under laboratory conditions, with more than 60% of juvenile mortality. The egg infection rate was above 62%, and the egg hatching rate was below 32%. The direct parasitism by the five taxa was confirmed by scanning electron microscope observation. The results of this study found a similar parasitism mechanism for T. longibrachiatum, T. harzianum, and M. chlamydosporia, where their hyphae and spores adhered to the M. javanica juveniles cuticle layer and formed trapping rings around them. The pot experiment results showed that T. harzianum and Lecanicillium spp. enhanced the plant growth parameters. Trichoderma longibrachiatum, abamectin, and the ethoprophos-based nematicides effectively decreased the reproduction rates of the nematode. The Trichoderma species and M. chlamydosporia significantly reduced the gall index and female fecundity of RKN. The treatment with BCAs and chemical nematicides involved a significant increase in the antioxidant activities of nematode-infected plants. The ethoprophos and fungal treatments decreased the MDA and total phenols content compared with the nematode-infested seedlings. This paper analyzes the advancements made towards the effective and efficient biocontrol of M. javanica using different fungal taxa, especially T. longibrachiatum and M. chlamydosporia, and the implications of these advancements for sustainable agriculture and food security. [ABSTRACT FROM AUTHOR]

The root-lesion nematode of the genus Pratylenchus Filipjev (1936) has a worldwide distribution and cause severe production constraints on numerous important crops. In 2013-14, during a survey of the apple nurseries and orchards in center of Tunisia (Kairouan, Zaghouan, Monastir and Kasserine), 70 different roots and soil samples were collected. The populations of root-lesion nematode were identified on the basis of their morphological and morphometric characters, and by molecular methods. Microscopic observation of females and males demonstrated the occurrence of Pratylenchusd vulnus on apple trees. The ribosomal DNA D2-D3 expansion segments of the 28S rRNA and of the Pratylenchus populations were PCR amplified and sequenced. The sequences were compared with those of Pratylenchus species in the GenBank database with high similarity (99%). This comparison reconfirmed the morphological identifications. Phylogenetic studies placed those populations with P. vulnus. This is the first report of P. vulnus infecting apple in Tunisia. [ABSTRACT FROM AUTHOR]

The combined use of entomopathogenic fungi and sublethal rate of chemical insecticides or other biological control agents have been proposed as an environmentally and sustainable strategy in the control of locust pests. In this paper, the quarter and the half of the recommended dose of Metarhizium anisopliae var. acridum (¼ and ½ Ma) and the aggregation pheromone (Phenylacetonitrile: PAN) were applied simultaneously and sequentially to Schistocerca gregaria fifth-instar nymphs. In addition, the physiological effects of PAN on locusts were assessed at the behavior, immune response, and biochemical level by evaluating for glutathione- S -transferase (GST), acetylcholinesterase inhibition (AChE), and malondialdehyde accumulation (MDA). Results showed that simultaneous application of PAN and the entomopathogenic fungus exhibited additive interaction. Synergistic interaction was also demonstrated when nymphs were exposed to PAN first, then treated with M. anisopliae var. acridum. Behavioral bioassay revealed that fifth-instar nymphs avoided the PAN odour and tended to remain away from the stimulus cup. In the choice assay, the pheromone significantly repelled the locusts at 2, 4, and 6 h of exposure which selected the PAN-free arena chamber. Moreover, treated nymphs become hyperactive and disoriented as evidenced by the cumulative distance travelled and the trajectory of locusts during the experiment. Immunological studies showed that PAN significantly decreased the differential haemocyte counts (prohemocytes and plasmatocytes) with a dose-response relationship. Data of biochemical analyzes showed that the PAN exposure reduced the activity of acetylcholinesterase and induced significantly the glutathione S -transferases and MDA concentration in the desert locust fifth-instar nymphs. Moreover, transcriptomic responses to the PAN exposure were evaluated using gene expression levels of CYP540 and GST. The transcript levels showed an up-regulation in GST expression level particularly in nymphs exposed for 4 and 6 h. A significant increase in CYP450 transcript level was also observed after 2 h of exposure, which decreased significantly after 4 and 6 h. Unlabelled Image • Simultaneous application of PAN and M. acridum exhibited additive interaction on S. gregaria. • The PAN acts as a repellent in the desert locust nymphs. • PAN significantly decreased the DHCs with a dose-response relationship. • The PAN reduced the activity of AChE and induced significantly the GSTs and MDA. [ABSTRACT FROM AUTHOR]