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Tomicus brevipilosus (Eggers) (Coleoptera: Curculionidae, Scolytinae) was recently discovered as a new pest of Yunnan pine (Pinus yunnanensis Franchet) in Yunnan Province in southwestern China. However, little was known on its reproductive biology and pattern of trunk attack on Yunnan pine. The objectives of this study were to better understand the reproductive biology of T. brevipilosus by investigating the seasonality of trunk attacks by parent adults for the purpose of reproduction (i.e., breeding attacks) and the within-tree pattern of these attacks. Our results showed that T. brevipilosus breeding attacks in P. yunnanensis generally started in early March and ended in early June in Anning County, Yunnan. T. brevipilosus exhibited two general patterns of infestation. From early March to mid-April, T. brevipilosus bred preferentially in the trunks of Yunnan pine trees that were already infested by Tomicus yunnanensis Kirkendall and Faccoli and Tomicus minor (Hartig), colonizing spaces along the trunk (mostly in the mid- and lower trunk) that were not already occupied by the other two Tomicus species. Later, from about mid-April to early June, when there were no Yunnan pine trees newly infested by T. yunnanensis and T. minor, T. brevipilosus attacked Yunnan pine by itself, infesting the lower parts of the trunk first and then infesting progressively upward along the trunk into the crown. Infestation by T. brevipilosus extends the total period that P. yunnanensis trees are under attack by Tomicus beetles in southwestern China, which helps explain why Yunnan pine has suffered high levels of tree mortality in recent decades.

Pinus yunnanensis is an important economic and ecological forest tree species in Southwest China. Nevertheless, the excellent resources are reducing, and an urgent and valid conservation strategy according to genetic information is required. Eighteen novel microsatellite markers were developed for P. yunnanensis, of which eight were polymorphic for the species. Markers were characterized using 32 individuals collected from three natural populations of P. yunnanensis with the observed and expected heterozygosity of 0.167–0.727 and 0.219–0.700, respectively. No significant linkage disequilibrium was detected between pairs of loci. Cross-species amplification of these microsatellite loci in the other five congeneric species was performed. These polymorphic microsatellite markers would be useful for investigating population genetic diversity to make conservation and management strategies of P. yunnanensis.

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Mass attack by the pine shoot beetle, Tomicus piniperda (L.), on the trunks of living trees was a main cause of Yunnan pine forest damages in Kunming, China, from the 1970s to 1990s. The present study, based on analysis of egg galleries, proposed that mass attack was initiated with the establishment of a few primary invaders and intensified as the partners followed. The attacking beetles increased with time in the first part of a mass attack. Dispersion of the population on the trunk surface was started from the positions the primary invaders colonized and spread to nearby locations. The population was mainly distributed in the upper and middle of trunk, but revealed the highest density in the middle.

1 In South-western China, Yunnan pines Pinus yunnanensis, suffer considerable damage from an undescribed Tomicus sp. previously thought to be T. piniperda. 2 To assess the effect of shoot maturation feeding (during which an aggregation process appears to occur) on host resistance to attacks on the bole, the relationships between shoot damage, bole attack density and tree survival were studied. 3 Attack distribution in the crown and in the stem did not vary between killed and surviving trees, indicating that mortality is determined by the quantity of attacks. 4 The level of shoot damage and bole attack density were positively and linearly correlated. This can be explained by the fact that bole attacks are caused by beetles coming from the crown of the same tree. 5 A critical threshold of bole attack density (around 80 attacks/m2) above which trees die was observed. However, because attacks continue after this threshold is reached, the density of failed attacks on the killed trees was used as an estimator of the threshold density. It decreased when shoot damage increased. 6 The existence of a critical threshold of shoot damage (60% damaged shoots) was also demonstrated. Above this threshold, stem attack density was always sufficiently high to kill trees. 7 The results emphasize that concentration of shoot attacks is the main reason for the extensive tree damage observed in China. 8 A model of relationships between shoot and stem attacks is proposed, suggesting that management to reduce shoot attacks would protect trees from dying by both decreasing the number of bole attacks and raising the threshold for successful attack density on the bole to levels that could not be attained.

NR 20140805

Fluorescence in situ hybridization (FISH) was employed on mitotic metaphase chromosome preparations of five Asian Pinus species: Pinus tabuliformis, Pinus yunnanensis, Pinus densata, Pinus massoniana and Pinus merkusii, using simultaneously DNA probes of the 18S rRNA gene and the 5S rRNA gene including the non-transcribed spacer sequences. The number and location of 18S rDNA sites varied markedly (5-10 pairs of strong signals) among the five pines. A maximum of 20 major 18S rDNA sites was observed in the diploid genome (2n = 24) of P. massoniana. The 5S rDNA FISH pattern was less variable, with one major site and one minor site commonly observed in each species. The differentiation of rDNA sites on chromosomes among the five pines correlates well with their phylogenic positions in Pinus as reconstructed from other molecular data. P. densata, a species of hybrid origin, resembles its parents ( P. tabuliformis and P. yunnanensis), including some components characteristic of each parent in its pattern. However, the species is unique, showing new features resulting possibly from recombination and genome reorganization.

Background The pine shoot beetle Tomicus yunnanensis (Coleoptera: Scolytinae) is an economically important pest of Pinus yunnanensis in southwestern China. Developed resistance to insecticides due to chemical pesticides being used for a long time is a factor involved in its serious damage, which poses a challenge for management. In addition, highly efficient adaptation to divergent environmental ecologies results in this pest posing great potential threat to pine forests. However, the molecular mechanisms remain unknown as only limited nucleotide sequence data for this species is available. Methodology/Principal Findings In this study, we applied next generation sequencing (Illumina sequencing) to sequence the adult transcriptome of T. yunnanensis. A total of 51,822,230 reads were obtained. They were assembled into 140,702 scaffolds, and 60,031 unigenes. The unigenes were further functionally annotated with gene descriptions, Gene Ontology (GO), Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genome (KEGG). In total, 80,932 unigenes were classified into GO, 13,599 unigenes were assigned to COG, and 33,875 unigenes were found in KO categories. A biochemical pathway database containing 219 predicted pathways was also created based on the annotations. In depth analysis of the data revealed a large number of genes related to insecticides resistance and heat shock protein genes associated with environmental stress. Conclusions/Significance The results facilitate the investigations of molecular resistance mechanisms to insecticides and environmental stress. This study lays the foundation for future functional genomics studies of important biological questions of this pest.

Heterologous hybridization of chloroplast DNA (cpDNA) involving 30 endonucleaseprobe combinations was used to analyze cpDNA variation in multiple individuals and populations of Pinus tabulaeformis (Carr.), Pinus yunnanensis (Franchet) and Pinus massoniana (Lamb.). Restriction fragment patterns detected by several combinations distinguished among the three species. The obtained cpDNA markers were subsequently used to examine cpDNA variation of Pinus densata (Masters), a putative tertiary hybrid between P. tabulaeformis and P. yunnanensis. The analysis demonstrated that P. densata populations harbor three different haplotypes. Two of these haplotypes are characteristic of P. tabulaeformis and P. yunnanensis. However, the third haplotype found in P. densata appears to be absent in other extant Asian Pinus species. It is suggested that the observed cpDNA composition of P. densata populations is a result of past hybridization involving P. tabulaeformis, P. yunnanensis, and a third unknown or extinct taxon. Chloroplast DNA polymorphism in P. densata was much greater than that for nuclear allozyme markers in this and the other Pinus species. Population differentiation was also substantial in P. densata and exceeded that for allozyme markers. In contrast, no cpDNA polymorphism was detected in populations of P. tabulaeformis, P. yunnanensis, and P. massoniana. The study suggests that interspecific gene exchange may lead to the creation of stable cpDNA polymorphism in conifer hybrids.

We describe a new and highly aggressive species of pine shoot beetle, Tomicus yunnanensis Kirkendall & Faccoli, which has been decimating Pinus yunnanensis forests in southwest China for almost three decades. This species was confused with T. piniperda until recent molecular studies showed the SW China populations to be quite divergent from T. piniperda of northeast China and Europe. The clearest morphological differences between these two species lie in the surface sculpture of the elytra: the new species has more widely spaced interstrial granules on the elytral disc, the punctures of interstria 2 on the declivity arranged irregularly and those of striae 1 and 3 smaller. The new species also has dense small hairs on the tip of the antennal club, while T. piniperda has only scattered small hairs on that segment. Mature T. piniperda specimens are uniformly black, while those of T. yunnanensis have the bulk of the elytra lighter than the base of the elytra and the pronotum. The new species is actually more similar to the Mediterranean species T. destruens, which differs in geographical distribution and in having the punctures of interstria 2 dense on the declivity and light-colored antennae. Species of Tomicus are of general concern to foresters because of their impact on conifer growth, but good illustrations for many species are lacking. We here provide a detailed key to all seven species of the genus (T. minor, T. piniperda, T. destruens, T. brevipilosus, T. yunnanensis and the virtually unknown T. puellus and T. pilifer) as well as diagnostic photographs and drawings. We summarize the biological differences between the new species and T. piniperda and recommend improved communication between taxonomists and forest entomologists, as avoidable taxonomic confusion such as that of T. yunnanensis and T. destruens with T. piniperda hinders the combatting of outbreaks of forest insects.

From 2000 to 2004, we studied wild edible mushrooms collected from forests of Yunnan pine (Pinus yunnanensis), a dominant vegetation in central Yunnan and adjacent regions. A total of 776 mushroom collections were obtained and identified, including 457 from the field investigation of the authors, 167 from mushroom markets, and 152 from specimens in the Herbarium of Cryptogams, Kunming Institute of Botany, Chinese Academy of Sciences. In total, 211 taxa belonging to 43 genera of 27 families were identified, among which 111 taxa in 35 genera of 23 families were commercial mushrooms traded in the local markets. Of these commercial mushrooms, 23.23% belonged to Russulaceae, comprising 15.17% (32 species) from the genus Russula and 8.06% (17 species) from the genus Lactarius. Boletaceae ranked the second in species richness and made up 19.43% (41 species) of the total species. Seventeen species found were from the family Tricholomataceae, 11 from Ramariaceae and Suillaceae, and 9 from Cantharellaceae, sharing 8.06%, 5.21%, 5.21% and 4.27% of the total species, respectively. More than 30 species from the genera Russula, Boletus, Lactarius, Ramaria, Suillus, Tricholoma, Cantharellus, and Thelephora made up 47.50% of the total wild commercial mushroom species in the Yunnan local markets. In recent years, increasing demand for wild edible mushrooms has resulted in largescale commercial harvesting, which has led to a decline of mushroom species. We appeal for protecting these valuable fungal resources and their habitats.

In southern China, when the original broadleaf evergreen forest is destroyed, pines are generally the first secondary tree species to invade the site. In Yunnan Province (southwestern China), Pinus yunnanensis is the principal secondary tree species. We examined two different secondary pine stands, one on the eastern slope and the other on the western slope of the Ailao Shan (mountains) of Yunnan in the Xujiaba Nature Reserve. Data was collected to determine the structure and composition of secondary forests after the destruction of the primary broadleaf evergreen forest. When compared, the primary broadleaf evergreen forest exhibits a much higher biodiversity and overall density than the secondary pine forests. When the two secondary stands are compared with each other, differences in structure and composition indicate that the Ailao Shans may produce a major climatic border between China's southwestern and southeastern monsoon systems. In addition, bird species were recorded in the stands and observations indicate that the Ailao Shans also mark a significant migratory border. Yunnan is an important biological region in China because it harbors over 50% of the country's plant and animal species. The proper management and protection of Xujiaba and other Nature Reserves in the Province will help maintain Yunnan's biological wealth. The protection of forest cover will also minimize environmental degradation, such as soil erosion, which is being experienced in other developing regions. As China aggressively modernizes, forest management based on ecological data is vital in order to protect remaining forests and help develop a sustainable rural economy.

Turpentines of Finns khasya 1 and Pinus insularis, and to a lesser degree of Pinus yunnanensis, obtained from various localities have been investigated. Data obtained indicate the existence of two chemical races of P. khasya: a northern (Assam and Burma) race characterized by high β-pinene, low β-phellandrene and high longifolene content, and a southern (Viet Nam) race characterized by low β-pinene, high β-phellandrene and low longifolene contents. No difference in turpentine composition was found between Pinus khasya from Viet Nam and Pinus insularis from the Philippines. 3-Carene was identified as a constituent of P. yunnanensis oleoresin ; this terpene is absent in both P. khasya and P. insularis. However these findings are based on only one sample of oleoresin collected from a few planted trees, and verification is desirable.

Pinus serotina turpentine was found to consist of l -α-pinene, 5 per cent; l -limonene, 90 per cent; methyl chavicol, 1 per cent; and 2 or 3 per cent of unidentified sesquiterpenes. P. tenuifolia turpentine contained: d -α-pinene, 77 per cent; l -β-pinene, 6 to 7 per cent; Δ 3 -carene, 8 per cent; terpinolene, 1 to 2 per cent; methyl chavicol (possibly) less than 1 per cent; linalool, about 1 per cent; sesquiterpene fraction, 1 per cent. P. yunnanensis turpentine contained l -α-pinene, 87 per cent; possibly small amounts of l -β-pinene; oxygenated terpene compounds, 5 or 6 per cent. Apparently there were no sesquiterpenes.