43 research outputs found
First Record of Fusarium verticillioides as an Entomopathogenic Fungus of Grasshoppers
Fusarium verticillioides (Saccardo) Nirenberg (Ascomycota: Hypocreales) is the most common fungus reported on infected corn kernels and vegetative tissues, but has not yet been documented as being entomopathogenic for grasshoppers. Grasshoppers and locusts represent a large group of insects that cause economic damage to forage and crops. Tropidacris collaris (Stoll) (Orthoptera: Acridoidea: Romaleidae) is a large and voracious grasshopper that in recent years has become an increasingly recurrent and widespread pest in progressively more greatly extended areas of some of in Argentina's northern provinces, with chemical insecticides being currently the only means of control. During February and March of 2008–09, nymphs and adults of T. collaris were collected with sweep nets in dense woodland vegetation at a site near Tres Estacas in western Chaco Province, Argentina, and kept in screened cages. F. verticillioides was isolated from insects that died within 10 days and was cultured in PGA medium. Pathogenicity tests were conducted and positive results recorded. Using traditional and molecular-biological methods, an isolate of F. verticillioides was obtained from T. collaris, and its pathogenecity in the laboratory was shown against another harmful grasshopper, Ronderosia bergi (Stål) (Acridoidea: Acrididae: Melanoplinae). The mortality caused by F. verticillioides on R. bergi reached 58 ± 6.53% by 10 days after inoculation. This is the first record of natural infection caused by F. verticillioides in grasshoppers
Pearl millet populations characterized by Fusarium prevalence, morphological traits, phenolic content, and antioxidant potential
Background: Pearl millet (Pennisetum glaucum L.) has become increasingly attractive due to its health benefits. It is grown as
food for human consumption and fodder for livestock in Africa and Asia. This study focused on five pearl millet populations
from different agro-ecological zones from Tunisia, and on characterization by morphological traits, total phenolic and flavonoid
content, antioxidant activity, and occurrence of Fusarium.
Results: Analysis of variance revealed highly significant differences between populations for the quantitative traits. The highest
grain weights occurred in the pearlmillet cultivated in Zaafrana and Gergis of Tunisia. Early flowering and earlymaturing populations
cultivated in the center (Zaafrana, Rejiche) and south (Gergis) of Tunisia tended to have a higher grain yield. The Zaafrana
population showed the highest value of green fodder potentiel (number andweight of leaves/cultivar and theweight of tillers and
total plant/cultivar) followed by Gergis and Rejiche. The Kelibia population showed the highest total phenolic and flavonoid content.
Rejiche exhibited the greatest antioxidant activity. Trans-cinnamic, protocatechuic, and hydroxybenzoic acids were the
major phenolic compounds in all the extracts. Three Fusarium species were identified in Tunisian pearl millet populations based
on morphologic and molecular characterization. Fusarium graminearum and Fusarium culmorum occurred most frequently. The
average incidence of the three Fusarium species was relatively low (<5%) in all populations. The lowest infection rate (0.1%)
was recorded in the samples from Zaafrana.
Conclusion: Chemometric analysis confirmed the usefulness of the above traits for discrimination of pearl millet populations,
where a considerable variation according to geographical origin and bioclimatic conditions was observed.
© 2020 Society of Chemical Industr
Replicating viral vector platform exploits alarmin signals for potent CD8<sup>+</sup> T cell-mediated tumour immunotherapy.
Viral infections lead to alarmin release and elicit potent cytotoxic effector T lymphocyte (CTL <sup>eff</sup> ) responses. Conversely, the induction of protective tumour-specific CTL <sup>eff</sup> and their recruitment into the tumour remain challenging tasks. Here we show that lymphocytic choriomeningitis virus (LCMV) can be engineered to serve as a replication competent, stably-attenuated immunotherapy vector (artLCMV). artLCMV delivers tumour-associated antigens to dendritic cells for efficient CTL priming. Unlike replication-deficient vectors, artLCMV targets also lymphoid tissue stroma cells expressing the alarmin interleukin-33. By triggering interleukin-33 signals, artLCMV elicits CTL <sup>eff</sup> responses of higher magnitude and functionality than those induced by replication-deficient vectors. Superior anti-tumour efficacy of artLCMV immunotherapy depends on interleukin-33 signalling, and a massive CTL <sup>eff</sup> influx triggers an inflammatory conversion of the tumour microenvironment. Our observations suggest that replicating viral delivery systems can release alarmins for improved anti-tumour efficacy. These mechanistic insights may outweigh safety concerns around replicating viral vectors in cancer immunotherapy