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

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

Potential interactions between invasive Fusarium circinatum and other pine pathogens in Europe

Pines are major components of native forests and plantations in Europe, where they have both economic significance and an important ecological role. Diseases of pines are mainly caused by fungal and oomycete pathogens, and can significantly reduce the survival, vigor, and yield of both individual trees and entire stands or plantations. Pine pitch canker (PPC), caused by Fusarium circinatum (Nirenberg and O'Donnell), is among the most devastating pine diseases in the world, and is an example of an emergent invasive disease in Europe. The effects of microbial interactions on plant health, as well as the possible roles plant microbiomes may have in disease expression, have been the focus of several recent studies. Here, we describe the possible effects of co-infection with pathogenic fungi and oomycetes with F. circinatum on the health of pine seedlings and mature plants, in an attempt to expand our understanding of the role that biotic interactions may play in the future of PPC disease in European nurseries and forests. The available information on pine pathogens that are able to co-occur with F. circinatum in Europe is here reviewed and interpreted to theoretically predict the effects of such co-occurrences on pine survival, growth, and yield. Beside the awareness that F. circinatum may co-occurr on pines with other pathogens, an additional outcome from this review is an updating of the literature, including the so-called grey literature, to document the geographical distribution of the relevant pathogens and to facilitate differential diagnoses, particularly in nurseries, where some of them may cause symptoms similar to those induced by F. circinatum. An early and accurate diagnosis of F. circinatum, a pathogen that has been recently introduced and that is currently regulated in Europe, is essential to prevent its introduction and spread in plantings and forests