The mycobiota of needles and shoots of silver fir (Abies alba Mill.) with symptoms of Herpotrichia needle browning in the Tatra Mts. (Poland)

The European silver fir (Abies alba Mill.) has the largest distribution area of all the European species of fir. It is the only species of this type found in the Carpathian Mts., including their highest range - the Tatras, where it constitutes one of the main components of lower montane forests. In certain sections of the Carpathian Mountains fir stands are affected by the competitive pressure of beech. This may be due to climate change, as well as biotic factors such as plant diseases. One such disease is Herpotrichia needle browning. The goal of the present research was to assess the occurrence of Herpotrichia needle browning in the Tatra National Park and determine the species composition of fungi colonizing symptomatic needles and shoots. Symptoms of the disease were observed across the entire research period, i.e., from May to mid-September 2019. They included the wilting of the needles with subsequent mycelial growth on the remains, as well as shoot deformation. The mycological analysis of the needles and shoots of A. alba resulted in the isolation of 22 fungal taxa. In the case of the needles and shoots, which showed symptoms of infection, the most frequent species of fungus was Sydowia polyspora (Bref. & Tavel) E. Müll., followed by Alternaria alternata (Fr.) Keissl. and Rhizosphaera macrospora Gourb. & M. Morelet. Herpotrichia needle browning seems to be triggered by a complex disease resulting from synergistic interaction of several fungal pathogens

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Impact of White Mistletoe (Viscum album ssp. abietis) Infection on Needles and Crown Morphology of Silver Fir (Abies alba Mill.)

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha4027906 ◽

2012 ◽

Vol 40 (2) ◽

pp. 152 ◽

Cited By ~ 8

Author(s):

Catalina O. BARBU

Keyword(s):

Abies Alba ◽

Viscum Album ◽

Middle Part ◽

Distribution Area ◽

Silver Fir ◽

Needle Length ◽

Eastern Border ◽

Crown Morphology ◽

The Difference ◽

Needle Loss

White mistletoe (Viscum album ssp. abietis (Wiesb.) Abromeit), (Santalales, Viscaceae) is a hemiparasite species and, in Romania,Â occurs only on silver fir (Abies alba Mill.). The species affects silver fir stands located mainly at lower elevations on the Eastern border ofÂ the silver fir natural distribution area. Along with drought and pollution, white mistletoe infection plays an important role in silver firÂ decline. The present study tried to quantify the mistletoe impact on crown degradation of silver fir trees, by measuring several parametersÂ such as needle length and needle loss. The data were collected from a pure silver fir stand where more than 70% of trees were affectedÂ by mistletoe. The results indicate that both mistletoe infection and branch position into the crown influence the needles length. TheÂ reduction in needle length was more evident in the upper and middle part of the crown and smaller in the lower part of the crown, asÂ well as in the â€œcompensation crownâ€ (formed by epicormic branches). The difference between needle lengths increases with the infectionÂ degree. In moderately and heavily infected trees, needles are falling in high proportion compared with low infected trees, demonstratingÂ that mistletoe is producing crown degradation significantly reducing the photosynthetic tissue.

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The soil fungal communities in nurseries producing Abies alba

BALTIC FORESTRY ◽

10.46490/bf426 ◽

2020 ◽

Vol 26 (1) ◽

Author(s):

Jolanta Behnke-Borowczyk ◽

Wojciech Kowalkowski ◽

Natalia Kartawik ◽

Mariena Baranowska ◽

Wladyslaw Barzdajn

Keyword(s):

Mycorrhizal Fungi ◽

Fungal Pathogens ◽

Abies Alba ◽

Fungal Communities ◽

Reference Sequence ◽

Silver Fir ◽

Fungal Organisms ◽

Forest Nurseries ◽

Generation Sequencing ◽

Forest District

Silver fir is an important forest-forming species in the mountain and upland parts of Poland. It was determined that fir lost the possibility of spontaneous return to the forests of the region. That is why the Polish State Forests has launched a programme to restore its resources in the Sudetes. Until now, fungi and their relationship with fir have not been fully addressed in the Sudetes Restitution Programme, therefore this study was undertaken. The aim of this study was to determine the species composition of soil fungi from quarters producing silver fir seedlings. The research material was rhizosphere soil collected from 3-year-old saplings produced in forest nurseries of the Międzylesie Forest District. Fungal composition was determined by Next-Generation sequencing (Illumina NextSeq 500). The total number of OTUs obtained (638 435) included sequences of cultivated horcultured fungi (433 412 OTUs = 52.7%), non-cultivable fungi, that is which cannot be cultured (97 108 OTUs = 22.41 %) and potential fungi with no reference sequence in UNITE (73 419 OTUs = 16.93%) and non-fungal organisms (34 496 = 7.96%). The following taxa as Mortierella sp. (8.23%). Tylospora sp. (6.68%) and Russula sp. (3.76%) had the largest share in the soil fungal communities. The results of the study indicate the dominance of saprotrophic and mycorrhizal fungi in the communities of fir roots, which proves that saplings are of good quality. Small share of pathogens sequences suggests that soil-born fungal pathogens are not a major threat to fir seedlings in nurseries. Key words: mycorrhizal fungi, nursery, Abies alba, seedlings, Międzylesie Forest District.

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Biological control of Phaseolus vulgaris and Pisum sativum root rot disease using Trichoderma species

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-021-00441-2 ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Hammad Abdelwanees Ketta ◽

Omar Abd El-Raouf Hewedy

Keyword(s):

Phaseolus Vulgaris ◽

Pisum Sativum ◽

Common Bean ◽

Root Rot ◽

Fungal Pathogens ◽

Plant Diseases ◽

Root Rot Disease ◽

Pea Root ◽

Rot Disease ◽

Pea Root Rot

Abstract Background Root rot pathogens reported to cause considerable losses in both the quality and productivity of common bean (Phaseolus vulgaris L.) and pea (Pisum sativum L.). It is an aggressive crop disease with detriment economic influence caused by Fusarium solani and Rhizoctonia solani among other soil-borne fungal pathogens. Destructive plant diseases such as root rot have been managed in the last decades using synthetic pesticides. Main body Seeking of economical and eco-friendly alternatives to combat aggressive soil-borne fungal pathogens that cause significant yield losses is urgently needed. Trichoderma emerged as promising antagonist that inhibits pathogens including those inducing root rot disease. Detailed studies for managing common bean and pea root rot disease using different Trichoderma species (T. harzianum, T. hamatum, T. viride, T. koningii, T. asperellum, T. atroviridae, T. lignorum, T. virens, T. longibrachiatum, T. cerinum, and T. album) were reported both in vitro and in vivo with promotion of plant growth and induction of systemic defense. The wide scale application of selected metabolites produced by Trichoderma spp. to induce host resistance and/or to promote crop yield, may represent a powerful tool for the implementation of integrated pest management strategies. Conclusions Biological management of common bean and pea root rot-inducing pathogens using various species of the Trichoderma fungus might have taken place during the recent years. Trichoderma species and their secondary metabolites are useful in the development of protection against root rot to bestow high-yielding common bean and pea crops.

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The Use of Essential Oils from Thyme, Sage and Peppermint against Colletotrichum acutatum

Plants ◽

10.3390/plants10010114 ◽

2021 ◽

Vol 10 (1) ◽

pp. 114

Author(s):

Armina Morkeliūnė ◽

Neringa Rasiukevičiūtė ◽

Lina Šernaitė ◽

Alma Valiuškaitė

Keyword(s):

Essential Oils ◽

Fungal Pathogens ◽

Control Plant ◽

Antimicrobial Activities ◽

Plant Diseases ◽

Colletotrichum Acutatum ◽

Low Toxicity ◽

Colletotrichum Spp ◽

Biological Protection

The Colletotrichum spp. is a significant strawberry pathogen causing yield losses of up to 50%. The most common method to control plant diseases is through the use of chemical fungicides. The findings of plants antimicrobial activities, low toxicity, and biodegradability of essential oils (EO), make them suitable for biological protection against fungal pathogens. The aim is to evaluate the inhibition of Colletotrichum acutatum by thyme, sage, and peppermint EO in vitro on detached strawberry leaves and determine EO chemical composition. Our results revealed that the dominant compound of thyme was thymol 41.35%, peppermint: menthone 44.56%, sage: α,β-thujone 34.45%, and camphor: 20.46%. Thyme EO inhibited C. acutatum completely above 200 μL L−1 concentration in vitro. Peppermint and sage EO reduced mycelial growth of C. acutatum. In addition, in vitro, results are promising for biological control. The detached strawberry leaves experiments showed that disease reduction 4 days after inoculation was 15.8% at 1000 μL L−1 of peppermint EO and 5.3% at 800 μL L−1 of thyme compared with control. Our findings could potentially help to manage C. acutatum; however, the detached strawberry leaves assay showed that EO efficacy was relatively low on tested concentrations and should be increased.

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Effect of earthworms on mycorrhization, root morphology and biomass of silver fir seedlings inoculated with black summer truffle (Tuber aestivum Vittad.)

Scientific Reports ◽

10.1038/s41598-021-85497-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tina Unuk Nahberger ◽

Gian Maria Niccolò Benucci ◽

Hojka Kraigher ◽

Tine Grebenc

Keyword(s):

Root System ◽

Root Biomass ◽

Fine Root ◽

Abies Alba ◽

Fine Root Biomass ◽

Root Tip ◽

Silver Fir ◽

Tuber Aestivum ◽

Root Tips ◽

Root Parameters

AbstractSpecies of the genus Tuber have gained a lot of attention in recent decades due to their aromatic hypogenous fruitbodies, which can bring high prices on the market. The tendency in truffle production is to infect oak, hazel, beech, etc. in greenhouse conditions. We aimed to show whether silver fir (Abies alba Mill.) can be an appropriate host partner for commercial mycorrhization with truffles, and how earthworms in the inoculation substrate would affect the mycorrhization dynamics. Silver fir seedlings inoculated with Tuber. aestivum were analyzed for root system parameters and mycorrhization, how earthworms affect the bare root system, and if mycorrhization parameters change when earthworms are added to the inoculation substrate. Seedlings were analyzed 6 and 12 months after spore inoculation. Mycorrhization with or without earthworms revealed contrasting effects on fine root biomass and morphology of silver fir seedlings. Only a few of the assessed fine root parameters showed statistically significant response, namely higher fine root biomass and fine root tip density in inoculated seedlings without earthworms 6 months after inoculation, lower fine root tip density when earthworms were added, the specific root tip density increased in inoculated seedlings without earthworms 12 months after inoculation, and general negative effect of earthworm on branching density. Silver fir was confirmed as a suitable host partner for commercial mycorrhization with truffles, with 6% and 35% mycorrhization 6 months after inoculation and between 36% and 55% mycorrhization 12 months after inoculation. The effect of earthworms on mycorrhization of silver fir with Tuber aestivum was positive only after 6 months of mycorrhization, while this effect disappeared and turned insignificantly negative after 12 months due to the secondary effect of grazing on ectomycorrhizal root tips.

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Biological control of strawberry crown rot, root rot and grey mould by the beneficial fungus Aureobasidium pullulans

BioControl ◽

10.1007/s10526-021-10083-w ◽

2021 ◽

Author(s):

Mudassir Iqbal ◽

Maha Jamshaid ◽

Muhammad Awais Zahid ◽

Erik Andreasson ◽

Ramesh R. Vetukuri ◽

...

Keyword(s):

Root Rot ◽

Fungal Pathogens ◽

Aureobasidium Pullulans ◽

Grey Mould ◽

Lesion Size ◽

Plant Diseases ◽

Crown Rot ◽

Whole Plants

AbstractUtilization of biocontrol agents is a sustainable approach to reduce plant diseases caused by fungal pathogens. In the present study, we tested the effect of the candidate biocontrol fungus Aureobasidium pullulans (De Bary) G. Armaud on strawberry under in vitro and in vivo conditions to control crown rot, root rot and grey mould caused by Phytophthora cactorum (Lebert and Cohn) and Botrytis cinerea Pers, respectively. A dual plate confrontation assay showed that mycelial growth of P. cactorum and B. cinerea was reduced by 33–48% when challenged by A. pullulans as compared with control treatments. Likewise, detached leaf and fruit assays showed that A. pullulans significantly reduced necrotic lesion size on leaves and disease severity on fruits caused by P. cactorum and B. cinerea. In addition, greenhouse experiments with whole plants revealed enhanced biocontrol efficacy against root rot and grey mould when treated with A. pullulans either in combination with the pathogen or pre-treated with A. pullulans followed by inoculation of the pathogens. Our results demonstrate that A. pullulans is an effective biocontrol agent to control strawberry diseases caused by fungal pathogens and can be an effective alternative to chemical-based fungicides.

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Impact of Industrial Pollution on Radial Growth of Conifers in a Former Mining Area in the Eastern Carpathians (Northern Romania)

Forests ◽

10.3390/f12050640 ◽

2021 ◽

Vol 12 (5) ◽

pp. 640

Author(s):

Cristian Gheorghe Sidor ◽

Radu Vlad ◽

Ionel Popa ◽

Anca Semeniuc ◽

Ecaterina Apostol ◽

...

Keyword(s):

Air Pollution ◽

Industrial Pollution ◽

Radial Growth ◽

Abies Alba ◽

Mining Operation ◽

Mining Area ◽

Silver Fir ◽

Local Pollution ◽

Eastern Carpathians ◽

The Impact

The research aims to evaluate the impact of local industrial pollution on radial growth in affected Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) stands in the Tarnița study area in Suceava. For northeastern Romania, the Tarnița mining operation constituted a hotspot of industrial pollution. The primary processing of non-ferrous ores containing heavy metals in the form of complex sulfides was the main cause of pollution in the Tarnița region from 1968 to 1990. Air pollution of Tarnița induced substantial tree growth reduction from 1978 to 1990, causing a decline in tree health and vitality. Growth decline in stands located over 6 km from the pollution source was weaker or absent. Spruce trees were much less affected by the phenomenon of local pollution than fir trees. We analyzed the dynamics of resilience indices and average radial growth indices and found that the period in which the trees suffered the most from local pollution was between 1978 and 1984. Growth recovery of the intensively polluted stand was observed after the 1990s when the environmental condition improved because of a significant reduction in air pollution.

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