Fungal endophytes in the needles of native and exotic pine species in a planta-tion in Northwestern Türkiye

The endophytic fungi present in needles of Pinus sylvestris, Pinus pinaster, Pinus nigra, Pinus taeda and Pinus radiata were investigated in Kerpe Research Forest, İzmit in 2016. Ten trees of each pine species were sampled systematically. Previous years green needles were sampled from the lower part of the canopy, from two equally spaced positions around the tree. Each needle was surface sterilized and cut into 0.5 cm sections then individually placed onto malt extract agar plates. DNA was ex-tracted from reprensentative seven isolates and amplified using primers ITS1 and ITS4 targeting the nuclear 5.8S rDNA gene and the two ITS regions flanked between 18S and 28S rDNA genes. Amplicons sequenced in both directions using the univer-sal fungal primers ITS1 and ITS4. Isolations from a total of 1000 needles (200 from each pine species) yielded 750 fungal isolates. Pestalotiopsis funerea (Desm.) Steyaert was isolated at the highest frequency followed by Acremonium sp., Cladio-sporum sp. and Cyclaneusma minus

Seydişehir İlçesi, Toros Göknarı meşcerelerinde Heterobasidion abietinum tarafından kaynaklanan çürüklüğün gövde içindeki gelişimi ve mücadelesi

Bu çalışmada, Seydişehir Orman İşletme Şefliği sınırları içinde yer alan karışık ve saf Toros göknarı meşcerelerinde bazı biyolojik etmenlerin ve kimyasalların, göknarlarda kök ve alt gövde çürüklüğüne neden olan Heterobasidion abietinum’ u engelleme üzerine etkileri ve bu ağaç türünde çürüklüğün gövde içindeki gelişimi araştırılmıştır. Arazi denemelerinde biyolojik mücadele etmenleri olarak, birer adet Trichoderma harzianum ve Phlebiopsis gigantea izolatı, kimyasallar olarak %30 üre (Tekkim) sulu solüsyonu ve boraks tozu kullanılmıştır. Çürüklüğün ağaç içindeki gelişiminin tespitine yönelik gerçekleştirilen çalışmada, biyolojik ve kimyasal muamelelerin yapıldığı alanlardan seçilen ağaçlardan, 1’er m aralıklarla diskler kestirilmiştir. Dip kütüğü seviyesinden başlayarak, her bir ağaçtan altı adet, toplamda 120 adet disk, laboratuvar koşullarında H. annosum s.l’a ait konidioforların varlığı açısından incelenmiştir. Toros göknarı meşcerelerinde H. abietinum’a karşı kimyasal ve biyolojik mücadele yöntemlerinin araştırıldığı bu denemelerde sırasıyla, üre, T. harzianum, boraks ve P. gigantea ile %98,90- 96,37- 96,25 ve 72,32 ortalama değerleri ile kontrole göre koruyuculuk sağlanmıştır. Bunun yanı sıra, patojen tarafından meydana getirilen çürüklüğün gövde içerisinde 5,5 m yüksekliğe kadar ulaştığı belirlenmiştir. Anahtar kelimeler: H. abietinum, Toros göknarı, Konya-Seydişehir, çürüklük, biyolojik mücadel

Seed quantity affects the fungal community composition detected using metabarcoding

Pest introductions via trade in tree seed may result from a lack of adequate survey and validation protocols. Developing better diagnostic protocols to identify potentially harmful pests and pathogens in forest tree seed is of critical importance. High-throughput sequencing-based barcoding and metabarcoding provide effective tools for screening potentially harmful organisms in various plant materials, including seeds. However, the sample size needed to detect the total microorganism diversity of a community is a major challenge in microbiome studies. In this work, we examined how increasing sample size (ranging between 100 and 1000 seeds) influences diversity of fungal communities detected by high throughput sequencing in Pinus sylvestris seeds. Our results showed that as sample size increased, fungal alpha diversity also increased. Beta-diversity estimators detected significant differences between the mycobiota from different samples. However, taxonomic and functional diversity were not correlated with sample size. In addition, we found that increasing the number of PCR replicates resulted in a higher abundance of plant pathogens. We concluded that for the purpose of screening for potentially harmful pathogens using HTS, greater efforts should be made to increase the sample size and replicates when testing tree seed

The possible usage of mycoviruses in biological control against tree pathogenic fungi

Mycoviruses in many organism including plant pathogenic fungi. They are mostly spread intracellularly via asexual and sexual reproduction of the fungi and cause some changes on them. Although many mycoviruses have no clear effect on their hosts, there are also many reports that they cause some phenotypic chances. Especially, they have effect on plant pathogenic fungi by increasing or decreasing their virulence. When they reduce the virulence of the host like in Chestnut canker sample, it is possible to use them in biological control. In this review, mycoviruses detected on some important fungal pathogens of forest trees both in our country and world were introduced and the studies carried out were summarized

From leaf to continent: The multi-scale distribution of an invasive cryptic pathogen complex on oak

The spatial distribution and niche differentiation of three closely related species (Erysiphe alphitoides, Erysiphe quercicola and Erysiphe hypophylla) causing oak powdery mildew was studied at scales ranging from the European continent, where they are invasive, to a single leaf. While E. alphitoides was dominant at all scales, E. quercicola and E. hypophylla had restricted geographic, stand and leaf distributions. The large-scale distributions were likely explained by climatic factors and species environmental tolerances, with E. quercicola being more frequent in warmer climates and E. hypophylla in colder climates. The extensive sampling and molecular analyses revealed the cryptic invasion of E. quercicola in nine countries from which it had not previously been recorded. The presence of the three species was also strongly affected by host factors, such as oak species and developmental stage. Segregation patterns between Erysiphe species were observed at the leaf scale, between and within leaf surfaces, suggesting competitive effects