scholarly journals Distribution pattern of entry holes of the tree-killing bark beetle Polygraphus proximus

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246812
Author(s):  
Shin-ya Takei ◽  
Kenta Köbayashi ◽  
Etsuro Takagi

Bark beetles attack their hosts at uniform intervals to avoid intraspecific competition in the phloem. Bark texture and phloem thickness also affect bark beetle attacks, and the bark characteristics are not spatially homogeneous; therefore, the distribution patterns of entry holes can demonstrate an aggregated distribution. Polygraphus proximus Blandford (Coleoptera: Scolytinae) is a non-aggressive phloephagous bark beetle that feeds on Far Eastern firs. They have caused mass mortality in Russia and Japan. However, the distribution pattern of entry holes of P. proximus and spatial relationships with bark characteristics have not been studied. Thus, we investigated the distribution pattern of entry holes of P. proximus. The distribution of entry holes was significantly uniform in most cases. As the attack density increased, an aggregated distribution pattern within a short distance (< 4.0 cm) was observed. The rough bark had a significantly higher number of entry holes than the remaining bark. The distribution pattern of entry holes demonstrated a significantly aggregated spatial association with rough bark. Finally, rough bark around knots had significantly thicker phloem than the remaining barks. These suggest that P. proximus may preferentially attack rough bark to reproduce in the thicker phloem under a rough bark surface.

2019 ◽  
Vol 24 (9) ◽  
pp. 1592-1603 ◽  
Author(s):  
Jeno Kontschán ◽  
Gábor Szőcs ◽  
Balázs Kiss ◽  
Alexander A. Khaustov

A new Oodinychus Berlese, 1917 species, O. scolytana sp. nov., was discovered and described from the galleries of bark beetles Polygraphus proximus Blandford from two different parts of Asian Russia. New associations are given for the trematurid mites and bark beetle species. Three bark beetle associated species from the Trichouropoda ovalis-group are moved into the genus Oodinychus as O. hirsuta (Hirschmann, 1972) comb. nov., O. rafalski (Wiśniewski & Hirschmann, 1984) comb. nov. and O. wilkinsoni (Hirschmann &Wiśniewski, 1986) comb. nov. Also, Oodinychus egypticus Abo-Shnaf, El-Bishlawy & Allam, 2018 is transferred to the genus Nenteria Oudemans, 1915.


2021 ◽  
Vol 14 (2) ◽  
pp. 32-39
Author(s):  
S. V. Dedyukhin ◽  
V. V. Titova

The data on the first finds in the Udmurt Republic (and the East of European Russia as a whole) of a dangerous invasive species of bark beetle of the Far Eastern origin - Polygraphus proximus Blandford, 1894, are presented. The species was discovered in 2019 simultaneously in four districts (Zavyalovsky, Malopurginsky, Kiyasovsky and Sarapulsky) of the central and southern parts of the republic. The established areas damaged by the Polygraphus proximus of forest stands are located both near railway tracks and highways, and in the depths of natural forests in which Siberian fir grows ( Abies sibirica Ledeb.), which indicates a long-term hidden invasion of the pest and its adaptation in Udmurtia. Further outbreak of the pest can lead to catastrophic consequences for forests with the participation of fir in the region. In addition, in the stands damaged by the Polygraphus proximus , an increase in the number of local species of longhorn beetles, associated with fir, is possible. In connection with the extreme potential harmfulness of this invader, it is necessary to carry out sanitary and recreational activities in order to localize and eliminate the identified outbreak foci of the pest, as well as to clarify the forest areas occupied by the Polygraphus proximus in the territory of the Udmurt Republic and adjacent regions, with introduction of quarantine and monitoring measures.


2018 ◽  
Vol 23 (12) ◽  
pp. 2373
Author(s):  
Pavel B. Klimov ◽  
A.A. Khaustov

Associations of scolytine bark beetles (Coleoptera: Curculionidae: Scolytinae) and histiostomatid mites (Acari: Histiostomatidae) are reviewed. Histiostomatids are associated with a total of 62 described species of bark beetles in 31 countries of the world, except for South America and Antarctica (262 non-redundant records). Non-accidental records include 21 mite species in the genus Histiostoma and 5 species in the Bonomoia/Probonomoia generic complex. The biological role of histiostomatids associated with bark beetles is largely unknown and needs further investigation. Available observations suggest that histiostomatids living in bark beetle galleries may feed on different fungi, including those pathogenic to the tree host and/or may serve as food supplement for developing bark beetle larvae (e.g., the fungal genus Ophiostoma). However, based on their mouthpart morphology, instead of feeding on fungi directly, histiostomatids may reduce fungal population sizes by releasing fungicides produced by their opisthonotal glands. Both feeding and phoretic stages of the mites commonly vector considerable numbers of fungal spores or conidia, including those of phloem-infesting, blue stain fungi (e.g., Ophiostoma, Ceratocystis, and Alternaria). Here we describe all developmental stages of a new species of the genus Histiostoma, belonging to the piceae-species group that includes many mite species associated with bark beetles. The new species, Histiostoma shiramba sp. n., was found in the galleries of the Sakhalin-fir bark beetle, Polygraphus proximus, an invasive pest that is quickly spreading outside of its native range in the Eastern Palaearctic, causing large-scale destruction of fir forests. We emend the following names (nom. emend.) to agree in gender with the generic name Histiostoma (gender neuter): Histiostoma capillatum, H. conjunctum, H. hungaricum, H. indetonsum, H. irinum, H. longisetum, H. margaritatum, H. medium, H. ovale, H. pannonicum, H. serratum, H. sordidum, H. spinosum, H. sylvestre, H. varium, H. virginianum. The name Histiostoma scheucheri is emended to Histiostoma scheucherae.


2019 ◽  
Vol 2 (1) ◽  
pp. 336-346
Author(s):  
Dhamon Oridilla B

Candi Village in Bandungan District is one of the Chili Supply Sub-district for Semarang Regency and surrounding area has agro-climate suitable for the development of various agricultural commodities supported by wide market opportunity, so it is suitable for agricultural business development. The purpose of this research is to identify the distribution pattern of red pepper, to know each value of commodity chains and distribution, to design alternative distribution pattern of red pepper.Population in this research is 88 respondents from 735 of member of chilli farmer in Desa Candi with total area of 150,3 hectare consisting of rice field, moor and yard. Methods of data analyst using quantitative approach is done by using Margin Marketing Analysis. The results include: (1) The pattern of distribution of existing farming business grows naturally in accordance with the developments and needs of the perpetrators, the actors in this pattern are farmers, wholesalers, collectors, wholesalers, retailers, consumers. (2) The value of the red chili commodity chain in this naturally grown pattern often makes pricing more dominant by traders, so farmers receive prices slightly lower than market prices. (3) Some obstacles faced in distributing red peppers are the difficulty of changing the mindset of the community about advanced farming, this is best utilized by market participants (chain of distribution) who are more informed and always keep abreast of market dynamics. Conventional marketing pattern by farmer cause price level accepted by farmer in general relatively smaller compared to price received by trader. Suggestions shorten the chain of distribution patterns, increase the added value of products and improve the bargaining position of farmers and for the government always guide / accompany farmers in getting accurate market information, which can be used as farmers in bargaining, Increased market transparency can act as a trigger for the functioning of a market, improved competition and increased adaptation to meet the needs of supply and opportunity to compete with market prices. Desa Candi di Kabupaten Bandungan adalah salah satu Kecamatan Penyedia Cabai untuk Kabupaten Semarang dan sekitarnya memiliki agroklimat yang cocok untuk pengembangan berbagai komoditas pertanian yang didukung oleh peluang pasar yang luas, sehingga sangat cocok untuk pengembangan bisnis pertanian. Tujuan dari penelitian ini adalah untuk mengidentifikasi pola distribusi cabai merah, untuk mengetahui masing-masing nilai rantai komoditas dan distribusi, untuk merancang alternatif pola distribusi cabai merah. Populasi dalam penelitian ini adalah 88 responden dari 735 anggota petani cabai di Desa Candi dengan total luas 150,3 hektar yang terdiri dari sawah, tegalan dan pekarangan. Metode analis data menggunakan pendekatan kuantitatif dilakukan dengan menggunakan Analisis Pemasaran Margin. Hasil meliputi: (1) Pola distribusi usaha pertanian yang ada tumbuh secara alami sesuai dengan perkembangan dan kebutuhan pelaku, pelaku dalam pola ini adalah petani, pedagang besar, pengumpul, pedagang besar, pedagang besar, pengecer, konsumen. (2) Nilai rantai komoditas cabai merah dalam pola yang dikembangkan secara alami ini sering membuat penetapan harga lebih dominan oleh para pedagang, sehingga petani menerima harga yang sedikit lebih rendah daripada harga pasar. (3) Beberapa kendala yang dihadapi dalam mendistribusikan paprika merah adalah sulitnya mengubah pola pikir masyarakat tentang pertanian maju, hal ini paling baik digunakan oleh pelaku pasar (rantai distribusi) yang lebih banyak informasi dan selalu mengikuti perkembangan dinamika pasar. Pola pemasaran konvensional oleh petani menyebabkan tingkat harga yang diterima petani pada umumnya relatif lebih kecil dibandingkan dengan harga yang diterima pedagang. Saran mempersingkat rantai pola distribusi, meningkatkan nilai tambah produk dan meningkatkan posisi tawar petani dan bagi pemerintah selalu membimbing / menemani petani dalam mendapatkan informasi pasar yang akurat, yang dapat digunakan sebagai petani dalam tawar-menawar, Peningkatan transparansi pasar dapat bertindak sebagai pemicu berfungsinya pasar, meningkatnya kompetisi dan peningkatan adaptasi untuk memenuhi kebutuhan pasokan dan peluang untuk bersaing dengan harga pasar.


Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1290
Author(s):  
Branislav Hroššo ◽  
Pavel Mezei ◽  
Mária Potterf ◽  
Andrej Majdák ◽  
Miroslav Blaženec ◽  
...  

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovakia) from 2014–2016, following a windthrow in May 2014. In total, we investigated 225 trees over eight transects. For every tree, we measured its morphological (tree height, crown characteristics), environmental (solar radiation, terrain conditions, trunk zenith), temporal (time since wind damage), and beetle infestation (presence, location of attack, bark desiccation) parameters. We applied Generalized Additive Mixed Models (GAMM) to unravel the main drivers of I. typographus infestations. Results: Over the first year, beetles preferred to attack broken trees and sun-exposed trunk sides over uprooted trees; the infestation on shaded sides started in the second year along with the infestation of uprooted trees with lower desiccation rates. We found that time since wind damage, stem length, and incident solar radiation increased the probability of beetle infestation, although both solar radiation and trunk zenith exhibited nonlinear variability. Our novel variable trunk zenith appeared to be an important predictor of bark beetle infestation probability. We conclude that trunk zenith as a simple measure defining the position of downed trees over the terrain can anticipate beetle infestation. Conclusions: Our findings contribute to understanding of the bark beetle’s preferences to colonize windthrown trees in the initial years after the primary wind damage. Further, our findings can help to identify trees that are most susceptible to beetle infestation and to prioritize management actions to control beetle population while maintaining biodiversity.


1980 ◽  
Vol 112 (7) ◽  
pp. 725-730 ◽  
Author(s):  
D. J. Goheen ◽  
F. W. Cobb

AbstractThe relationship between bark beetle infestation of ponderosa pine and severity of infection by Ceratocystis wageneri was investigated by closely monitoring 256 trees (136 apparently healthy, 60 moderately diseased, and 60 severely diseased at initiation of study) for beetle infestation from summer 1972 to fall 1975. Disease ratings were updated by periodic examination, and some trees changed disease category during the study. Ninety trees were infested by Dendroctonus brevicomis, D. ponderosae, or both, five by buprestids alone, and one tree died from effects of the pathogen alone. Sixty-two of the beetle-infested trees were severely diseased at time of infestation, 25 were moderately diseased, and only three were apparently healthy. Thus, the results showed that bark beetles were much more likely to infest infected than healthy trees. Among diseased trees, those with advanced infections were most likely to be infested. There was evidence that buprestids (especially Melanophila spp.) and possibly Ips spp. attacked diseased trees prior to Dendroctonus spp. infestation.


Sign in / Sign up

Export Citation Format

Share Document