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Abstract: BACKGROUND: In addition to their services as predators, mirid predators are able to induce plant defences by phytophagy. However, whether this induction occurs in sweet pepper and whether it could be an additional benefit to their role as a biological control agent in this crop remain unknown. Here, these questions were investigated in two model insects, the mirids Nesidiocoris tenuis and Macrolophus pygmaeus. RESULTS: Plant feeding behaviour was observed in both N. tenuis and M. pygmaeus on sweet pepper and occupied 33% and 14% of total time spent on the plant, respectively. The punctures caused by mirid plant feeding induced the release of a blend of volatile organic compounds (VOCs) which repelled the herbivore pests Frankliniella occidentalis and Bemisia tabaci and attracted the whitefly parasitoid Encarsia formosa. The repellent effect on B. tabaci was observed for at least 7 days after initial exposure of the plant to N. tenuis, and attraction of E. formosa remained functional for 14 days. CONCLUSION: Plant defences induced by the feeding of mirid predators, their subsequent effects on the behaviour of both pests and natural enemies, and the persistence of these observed effects open the door to new control strategies in the sweet pepper crop. Further application of this research is discussed, such as the vaccination of plants by zoophytophagous mirids in the nursery before transplantation. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Crown rot, caused by Fusarium culmorum and Fusarium pseudograminearum, is one of the most pervasive diseases of wheat throughout the world . Fusarium culmorum is the most prevalent causal agent in Turkey while F. pseudograminearum is the most predominant in the USA. Consistent and reliable screening methods are required to accelerate the identification and development of wheat cultivars for resistance to Fusarium crown rot in breeding programs. A multifactor experiment with seven replicates was established investigating three different inoculation techniques (seedling dip, stem base droplet and colonized grain) using two pathogenic isolates of F. culmorum in Turkey and Fusarium pseudograminearum in the USA, respectively, against known moderately resistant and susceptible wheat cultivars under controlled greenhouse conditions. Plants were harvested and evaluated for crown rot severity using a 0-10 rating scale. Results indicated that disease severity was greater in seedling dip, compared to colonized grain, and stem base inoculation (in decreasing order of severity), respectively. However, the colonized grain method produced an adequate level of severity and consistent cultivar ranking in both experiments. Results showed significant cultivar × inoculation method interactions, and the two species of Fusarium were considered to be virulent. [ABSTRACT FROM AUTHOR]

Zoonotic disease control presents significant costs and challenges in human and wildlife populations. Although spatial variability and temporal variability in host populations play a significant role influencing the spread and persistence of pathogens, their impact on the effectiveness of disease control are not well understood., Field studies are impractical for many zoonotic diseases; thus, simulation modelling is an alternative. Some research has experimented with metapopulation models of host-pathogen systems, with discrete host populations distributed on a network of connections or on a one-dimensional transect of contiguous cells. Little attention has been paid to treating geographic space as a fine-grained two-dimensional continuum, a more appropriate spatial model for many generalist host and vector species., Using raccoon rabies as an example, we apply an individual-based spatially explicit stochastic simulation model to evaluate effectiveness of vaccination barrier strategies to control rabies. Barrier width and immunization levels are varied over landscapes with habitats of varying quality and spatial heterogeneity, resulting in varying degrees of host connectivity., Our results demonstrate that spatial heterogeneity in the landscape does affect vaccination efficacy. The probability that rabies will breach a vaccination barrier is greater and rabies incidence is higher in landscapes with (i) overall good-quality homogeneous habitat and (ii) overall poor-quality habitat with high spatial heterogeneity, than in landscapes with overall good-quality habitat and high spatial heterogeneity. The influence of landscape conditions on disease dynamics decreases with increasing population immunity., Synthesis and applications. Using a spatially explicit stochastic simulation model, we demonstrated that landscape spatial heterogeneity and vaccination control will interact to influence the success of controlling infectious disease outbreaks. Further, under some landscape conditions, insufficient vaccination is counter-productive because immunized individuals (i) reduce the number of disease transmitting contacts, preventing the disease from growing rapidly thus depleting the susceptible population; and (ii) survive to replenish the stock of susceptible animals through reproduction, facilitating disease persistence. [ABSTRACT FROM AUTHOR]

The transcript accumulation of the genes POX (peroxidase), GLU (β-1,3-glucanase), PR-1 (pathogenesis-related protein 1) and EAS (5-epi-aristolochene synthase, involved in capsidiol biosynthesis), the activity of peroxidase and glucanase, and the content of capsidiol in roots of chili (Capsicum annuum) CM-334 inoculated with Nacobbus aberrans (Na), Phytophthora capsici (Pc) and both pathogens were determined. Plants of CM-334 were inoculated with 2,000 J2 of N. aberrans and/or 300, 000 zoospores of P. capsici. At 6, 12, 24 and 48 h after of inoculation (hai) with the oomycete the expression of the mentioned genes was analyzed by real time PCR, and the activity of β-1,3-glucanase and peroxidase and the content of capsidiol were determined. In chili CM-334 inoculated only with Pc the EAS transcripts showed the maximum expression (23.4 times) at 6 hai, whereas in the interaction Na-Pc, there was a significant reduction (6.9 times) of EAS transcripts at this time. CM-334 plants inoculated with N. aberrans showed low levels of EAS and PRs genes, which contrasted significantly with gene transcript accumulation in the interaction CM-334-P. capsici. The transcripts of PRs were detected from 6 hai, and increased gradually until 48 hai. The activity of β-1,3-glucanase and peroxidase in CM-334 inoculated only with N. aberrans was low with respect to those inoculated with P. capsici or both pathogens, where the activity was significantly greater (P ≤ 0.05) at 12, 24 and 48 hai. In roots of CM-334 plants inoculated only with nematode the content of capsidiol was reduced by 31.6, 54.4, 57.2 and 66.6% with respect to the inoculated only with P. capsici; however in the roots where P. capsici was present (treatments Pc and Na-Pc), significant (P ≤ 0.05) greater levels were registered. [ABSTRACT FROM AUTHOR]