In this review, an overview was given of the mutual interactions between nematodes and fungi of the genus Trichoderma sp. due to the potential of these fungi to protect plant roots from ...plant-parasitic nematodes on the one hand and the influence of nematodes (fungivores) on the efficacy of the fungus on the other. In addition, an overview of the advantages of Trichoderma sp. for agricultural production was given. The basis of sustainable agricultural production is the healthy functioning of the soil ecosystem. The diversity of organisms—bacteria, protozoa, algae, metazoans (nematodes) and fungi—improves the quality and performance of the soil by maintaining biological productivity. Root exudates in the rhizosphere support microbial communities that play a key role in regulating the dynamics of organic matter decomposition and the availability of plant nutrients. The microbial activity of organisms in the soil is interconnected and interacts to form a soil food web that reflects the condition, function and health of the soil. The energy in food webs flows through trophic chains of consumers, which are divided into energy channels. Root, bacterial and fungal channels increase soil biomass, carbon (C) and energy flow through the soil food web. The structure of the nematode community is an effective tool for the biological assessment of soil quality. This is due to a number of characteristics that nematodes have, including the following: a great diversity of species, the possibility of subdivision according to different criteria such as trophic groups and c-p groups, the duration of reproduction, the ease of sampling, the identification of genera and preservation, etc. Nematodes are involved in various ecological functions in the soil, of which the interaction between them and fungi is based on antagonism or mutualism, which is the basis for a better understanding of their impact on the ecosystem. Fungi of the genus Trichoderma sp. are successful colonizers of all habitats, secondary opportunists and fast growing.
Interactions between soil biota communities play an important role as intrinsic factors of suppression and degradation of different phytopathogenic soil fungi. There is significant evidence that ...earthworms can directly affect fungal populations by feeding or by dispersing fungal propagules. Possible effects of indirect contact by secretion of mucus and coelomic fluid were not assessed previously. In the present laboratory study the effects of earthworms' coelomic fluid extract on the growth of Fusarium oxysporum, a phytopathogenic fungi species important in agricultural production, were assessed. The results showed that extracts of coelomic fluid of both tested earthworm species (Dendrobaena veneta and Eisenia fetida) have negative effects on fungal growth. After 48 h, a significant growth reduction was observed in groups treated with extracts containing 2250, 4000 and 4500 coelomocytes/mL. Growth reduction was even more pronounced 72 h after the treatment. The obtained results indicate the possibility that earthworms can affect soil fungi not only by ingestion, but also by contact interaction. This study proved that earthworm coelomic fluid extract shows antifungal activity in in vitro testing. For better understanding of the exact mechanism, studies with soil as a substrate are required, as well as in depth investigation of contact interactions between earthworms and fungi.
•Assessment of effects of two earthworm species'coelomic fluid on growth of fungi.•Growth inhibition of F. oxysporum after treatment with coelomic fluid extract.•Possible antifungal properties of two earthworm species' coelomic fluid extracts.•Evidence that earthworms might negatively affect F. oxysporum by contact.
Eleven pyridine derivatives were prepared by quaternization reactions by different synthetic routes: conventional, microwave, and ultrasound. Since acetone and other solvents used in conventional ...quaternization reactions are harmful, attempts were made to replace the organic solvents with more environmentally friendly alternative - deep eutectic solvents. The reactions were carried out using pyridine-3-aldoxime, pyridine-4-aldoxime, isonicotinamide and nicotinamide as nucleophiles and three different dihaloalkanes as electrophiles: diiodopropane, dibromopropane and diiodohexane. The results showed that the microwave method using acetone as solvent was significantly faster and gave higher yields than the conventional method. In contrast, synthesis in the eutectic solvents choline chloride: urea gave significantly lower yields. The structures of the synthesized compounds were confirmed by .sup.1H and .sup.13C NMR spectroscopy, mass spectrometry and elemental analysis. The antifungal activity of all compounds was tested at two different concentrations (10 and 100 microg mL.sup.-1) against Botrytis cinerea, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiorum in vitro. All tested compounds showed excellent inhibitory activity against the studied phytopathogenic fungal species at a concentration of 100 microg mL.sup.-1. Keywords: antifungal activity, dihaloalkanes, deep eutectic solvents, microwave synthesis, quaternization, pyridine derivatives, ultrasound synthesis.
Abiotic and biotic stresses, such as mineral nutrition deficiency (especially nitrogen) and
attack, pose a global threat with devastating impact on wheat yield and quality losses worldwide. This ...preliminary study aimed to determine the effect of
inoculation and two different nitrogen levels on oxidative status and antioxidative response in nine wheat varieties. Level of lipid peroxidation, activities of antioxidant enzymes (catalase, ascorbate peroxidase, glutathione reductase), phenolics, and chloroplast pigments content were measured. In general, wheat variety, nitrogen, and
treatment had an impact on all tested parameters. The most significant effect had a low nitrogen level itself, which mostly decreased activities of all antioxidant enzymes and reduced the chloroplast pigment content. At low nitrogen level,
treatment increased activities of some antioxidative enzymes, while in a condition of high nitrogen levels, antioxidative enzyme activities were mostly decreased due to
treatment. The obtained results provided a better understanding on wheat defense mechanisms against
under different nitrogen treatments and can serve as an additional tool in assessing wheat tolerance to various environmental stress conditions.
U istraživanju je ispitivano djelovanje eteričnih ulja domicilnoga bilja Hrvatske na supresiju rasta micelija Botrytis cinerea izoliranoga s vinove loze. U pokusu su korištena ulja sljedećih biljaka: ...metvice paprene (Mentha x piperita), kadulje (Salvia officinalis), ružmarina (Rosmarinus officinalis), lavandina (Lavandula hybrida), mravinaca (Origanum compactum), timijana (Thymus vulgaris), gospine trave (Hiperici oleum), stolisnika (Achillea millefolium) i smilja (Helichrysum italicum). Rezultati in vitro volatilnogq testa i makrodilucijskoga testa pokazali su da ulja timijana i paprene metvice mogu imati pozitivan utjecaj na inhibiciju rasta gljive Botrytis cinerea pri svim ispitivanim koncentracijama te da fungistatski učinak traje i preko 96 h. Primjena ulja stolisnika i gospine trave u makrodilucijskoj metodi dala je bolje rezultate u odnosu na volatilnu metodu. Eterično ulje smilja stimuliralo je porast micelija B. cinerea u obje metode. S obzirom na smanjenje porasta micelija B. cinerea u uvjetima in vitro, eterična ulja, kao biofungicidi, predstavljaju moguću zamjenu za sintetske pripravke u suzbijanju razvoja sive plijesni na vinovoj lozi, no potrebna su dodatna istraživanja kako u uvjetima in vitro, tako i u uvjetima in vivo.
Fuzarijska palež klasova (FHB) pšenice ekonomski je značajna bolest koja može imati nepovoljne posljedice na prinos i kvalitetu pšenice. Do danas ne postoji mjera zaštite koja osigurava potpunu ...zaštitu usjeva pšenice, ali kombinacija više mjera može dati dobre rezultate. Učinkovitost svake pojedine mjere pod utjecajem je okolišnih uvjeta koji prevladavaju tijekom vegetacijske sezone, a učinkovitost će ovisiti i o osjetljivosti pojedine sorte na FHB. Sve veći broj istraživanja potvrđuje kako je integrirana zaštita bilja (IZB) ključ za što uspješniju borbu protiv FHB-a. Kako bi primijenjene mjere zaštite bile što uspješnije, od iznimne je važnosti dobro poznavati uzročnika bolesti, njegov životni ciklus i ekologiju. Budući da je F. graminearum dominantni uzročnik FHB-a na području Republike Hrvatske, osobiti naglasak je stavljen na sve dostupne mjere zaštite u njegovu suzbijanju.
Fusarium head blight (FHB) is an economically devastating disease that may exert an adverse impact on the wheat yield and quality. To date, no measure ensures a complete protection of wheat crops, but the combination of multiple protection measures may produce the promising results. The effectiveness of each measure is influenced by environmental conditions during the growing season and cultivar susceptibility to the FHB. The Integrated Pest Management (IPM) is the most effective approach to the management of FHB. For a successful control, it is essential to acquire a good knowledge of the pathogen, its life cycle, and its ecology. Since the F. graminearum is a predominant species causing the FHB on the wheat in Croatia, this paper aims to describe all available measures for its control.
During cultivation, wheat is exposed to several abiotic and/or biotic stress conditions that may adversely impact the wheat yield and quality. The impact of abiotic stress caused by nitrogen ...deficiency and biotic stress caused by phytopathogenic fungus Fusarium culmorum on biomarkers of oxidative stress in the flag leaf of nine winter wheat varieties (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix, and Bezostaya-1) was analyzed in this study. Hydrogen peroxide concentration and lipid peroxidation level were measured as indicators of oxidative stress, while the antioxidant response was determined by measuring the concentration of phenolic compounds and activities of antioxidant enzymes. Wheat variety and nitrogen treatment had a significant effect on all examined biomarkers of oxidative stress in the flag leaf, while the impact of Fusarium treatment was less pronounced. The most significant impact on the measured stress biomarkers had a low nitrogen level, which mainly increased hydrogen peroxide concentration and lipid peroxidation level and decreased activities of antioxidant enzymes in most varieties. The obtained results were discussed and compared with the previous study in which biochemical analyzes were performed on the wheat spike. There was no significant strong correlation between flag leaf and spike response in the measured parameters, which, in addition to the variety-specific response, also indicates a tissue-specific antioxidant response.
The effect of different conservation soil tillage (CST) treatments and different level of nitrogen fertilization on Fusarium wheat grain infection on two locations are presented in this paper. The ...research was conducted on winter wheat with different soil tillage treatments: conventional tillage to 30 cm depth, subsoiling to 35-40 cm depth, chiselling up to 25 cm, disk-harrowing to 10-15 cm and no-tillage, without any tillage treatments and three different nitrogen rates (N1 - amount reduced by 30% of recommended; N2 - according to standard recommendation and N3 - amount increased by 30% of recommended). The occurrence of Fusarium species was determined in all the tested variants of tillage and fertilization treatments. The effect of reduced fertilization (N1) on Fusarium sp. grain infection in all tillage treatments was statistically lower in comparison with other (N2 and N3) nitrogen treatments. The lowest percentage of wheat grains infected with Fusarium sp. was recorded in conventional tillage on location Magadenovac and no tillage treatments on location Cacinci.
U radu je prikazan utjecaj različitih konzervacijskih sustava obrade tla i različitih razina gnojidbe dušikom na zarazu zrna pšenice vrstama Fusarium. Pokus je postavljen na dvije lokacije s pet sustava obrade tla: konvencionalna obrada s oranjem do 30 cm, podrivanje na dubinu 35-40 cm, rahljenje do 25 cm, tanjuranje na 10-15 cm i te direktna sjetva bez ikakve obrade tla, kao i s tri razine gnojidbe dušikom: N1- umanjena za 30% u odnosu na preporuku; N2 - prema preporuci i N3 - uvećana za 30% u odnosu na preporuku. Pojava zrna zaraženih vrstama Fusarium utvrđena je u svim istraživanih tretmana. Postotak zaraženih zrna vrstama Fusarium bio je statistički značajno niži na tretmanu gnojidbe N1 u odnosu na varijante gnojidbe N2 i N3. Najniži postotak zaraženih zrna pšenice zabilježen je kod konvencionalne obrade tla u Magadenovcu i no tillage tretmana u Čačincima.
The effect of five essential oils (anise, peppermint, basil, rosemary and true lavander) and their two most common components on the mycelial growth in Colletotrichum coccodes, economically important ...phytopathogic fungi and compared with fungicides have been investigated in the study. Tests were conducted in vitro conditions in eight volumes on a PDA substrate in four replicates. The increase in mycelium was measured on the eighth and fifteenth day after the mycelium inoculation. It was found out that some essential oils and components applied at a given volume have a significant antifungal effect, in some examples comparable to fungicides. Anise and peppermint essential oils as well as the anethole component had the best activity and the lowest IC50. Fifteen days after the inoculation of the mycelium, the essential oils had a significantly better antifungal activity compared to their second most represented component.
Leaf spot symptoms were spotted in two olive orchards in Istria and in Kvarner Gulf, Croatia. Fungal species from three representative isolates (P13 LECIII, R18 BI, JA20 NP) have been morphologically ...characterized based on the colony and conidial characteristics. Several techniques were performed for inducing the sporulation of the JA20 NP isolate. Only PDA + banana medium was successful. PCR was conducted for ITS, TUB, and EF1α gene regions. Phylogenetic analyses were performed using internal transcribed spacer, beta-tubulin, and translation elongation factor 1-alpha sequence data. Three types of tests were conducted: a pathogenicity test on detached leaves, on detached and scratched leaves, and on olive seedlings. Ultimately, from the morphological characterizations, DNA sequence analysis of ITS, TUB, and EF1α gene regions, and phylogenetic analysis, these species were identified as Nigrospora gorlenkoana Novobr., Nigrospora osmanthi Mei Wang & L. Cai, and Nigrospora philosophiae-doctoris M. Raza, Qian Chen & L. Cai. This is the first report of Nigrospora species causing leaf spot on olive trees and the first report of Nigrospora philosophiae-doctoris as a plant pathogen. Fungal leaf diseases in conditions that are favorable for infection and disease development can lead to a decrease in the yield and olive oil quality. Therefore, it is necessary to conduct further research and the monitoring of fungal leaf diseases.
PDF
