Molecular approach to determine taxonomic status of <Emphasis Type="Italic">Septoria</Emphasis> sp. causing leaf blotch of <Emphasis Type="Italic">Castanea sativa</Emphasis> in Hyrcanian forests

Castanea sativa is a valuable tree species in Hyrcanian forests, an evolutionary relict ecosystem whose communities suffer from overexploitation and fungal diseases. In the current study, three species delimitation methods were utilized with ITS regions sequencing to determine the taxonomic status of Septoria causing leaf blotch of C. sativa in Hyrcanian forests. The results indicated that the length of ITS region in the genus Septoria (extracted from GenBank) varied from 650 to 680 bp. There were almost three times more variable sites in ITS1 than in ITS2. The ITS2 secondary structure of Hyrcanian Septoria community had the highest similarity with Septoria castaneicola, except for some differences in helix II and III. Also, Hyrcanian samples had minimum genetic distances with S. castaneicola and maximum with Septoria quercicola. The maximum parsimony method divided the studied Septoria genus into three distinct clades, mostly located in clade I. Clade II consisted entirely of Septoria aciculosa, while clade III contained S. castaneicola as well as Hyrcanian samples.     

Sequencing and quantifying plastid DNA fragments stored in sapwood and heartwood of <Emphasis Type="Italic">Torreya nucifera</Emphasis>

The selection of wood species and the styles of sculpture play key roles in the characterization of Buddhist statues. After Jianzhen, a Chinese Buddhist monk, visited Japan in the mid-eighth century, wood of the genus Torreya had been frequently used to produce single-bole statues. Establishing measures for the accurate identification of wood in the genus Torreya is effective for investigating the drastic change in the production of statues during this period. Analyzing the plastid deoxyribonucleic acid (DNA) fragments extracted from wood is considered helpful in the identification of species in the same genus. This study analyzed the sequences and residual amounts of plastid DNA fragments in the wood of Torreya nucifera. Nucleotide substitutions in the plastid DNA were clearly identified between T. nucifera and the species distributed in China, indicating that the wood of Torreya sp. can be discriminated based on the plastid DNA sequences. DNA polymorphism analyses revealed sequence diversity for the intergenic spacers on the T. nucifera plastid DNA. A series of polymerase chain reaction (PCR) analyses demonstrated that the plastid DNA fragments with a length of approximately 100 bp could be amplified from the residual DNA extracted from the T. nucifera sapwood with longer elapsed years after cutting. Therefore, an identification of wood species in the genus Torreya based on their plastid DNA is considered to be one of the most effective measures taken in the study regarding the historical changes of Buddhist statues.     

Analysis of SSR loci and development of SSR primers in <Emphasis Type="Italic">Eucalyptus</Emphasis>

In this study, 28,691 genome sequences and 16,566 expressed sequence tags (ESTs) of Eucalyptus were derived from the GenBank database. A total of 2292 SSR loci were sought out from 1785 effective sequences. Through analyses of SSR loci information, the SSR motif length was negatively correlated with the abundance of the SSRs. In the EST sequences of Eucalyptus, triplet repeat motifs were the most abundant, and dinucleotide repeats motifs had the highest frequencies. Subsequently, 395 pairs of primers were designed based on the SSR loci. Using optimized SSR-PCR conditions, 340 pairs of primers were successfully screened, with a success rate of 86.1%. By construction of a maximum likelihood phylogenetic tree of six eucalypt species, represented by five species of the genus Eucalyptus and one of the genus Corymbia, the genetic relationships of Eucalyptus urophylla and E. camaldulensis suggested by this tree was found to differ from that suggested by traditional morphological taxonomy. The results provide insights for evaluating genetic diversity of Eucalyptus and analysis of Eucalyptus phylogenetics using SSR markers.     

Host specificity of Asian parasitoids for potential classical biological control of <Emphasis Type="Italic">Drosophila suzukii</Emphasis>

The Asian spotted wing drosophila, Drosophila suzukii, has recently become a serious pest of soft fruits in Europe. Classical biological control through the introduction of larval parasitoids from its native range in Asia is presently being considered. However, host specificity of potential biological control agents has to be determined to avoid releasing species that may have unintended non-target impacts. Larvae of six different European non-target fly species and the target D. suzukii were exposed either on diet or blueberries to three Asian larval parasitoids, Asobara japonica, Leptopilina japonica, and Ganaspis cf. brasiliensis, and one European species, Leptopilina heterotoma. Asobara japonica showed the lowest specificity, attacking and developing in all Drosophilidae. Leptopilina japonica successfully parasitized two non-target Drosophilidae, D. melanogaster and D. subobscura, with one singly progeny emerging from D. immigrans. Ganaspis cf. brasiliensis had the highest level of specificity but variations occurred between two geographical populations tested. A Japanese population was strictly specific to D. suzukii, whereas another population from China parasitized D. suzukii, D. melanogaster and sporadically D. subobscura. The European L. heterotoma successfully developed in D. melanogaster, D. subobscura and occasionally in D. immigrans, but nearly all eggs and larvae in D. suzukii were encapsulated. These results show that Ganaspis cf. brasiliensis is the species with the highest potential for biological control, but more studies are needed on its taxonomic status and the existence of biotypes or cryptic species varying in their specificity before field releases can be conducted in Europe.     

The susceptibility of Asian,European and North American <Emphasis Type="Italic">Fraxinus</Emphasis> species to the ash dieback pathogen <Emphasis Type="Italic">Hymenoscyphus fraxineus</Emphasis> reflects their phylogenetic history

In Europe, common ash (Fraxinus excelsior) is being decimated because of the invasive fungus Hymenoscyphus fraxineus. In its native range in Asia this ascomycete is considered a harmless leaf associate of F. mandshurica and F. chinensis subsp. rhynchophylla. Field observations from Europe suggest that there is species-specific variation in disease susceptibility among European and North American Fraxinus species, but a wider comparison at the genus level has been missing so far. We assessed disease symptoms and pathogen apothecium development in 17 Fraxinus species from Asia, Europe and North America exposed to high infection pressure in a Danish arboretum. We also tested their susceptibility to pathogen infection through controlled stem and leaf inoculations and subsequently assessed the level of pathogen DNA by a qPCR assay. The results suggested the presence of a phylogenetic signal in disease susceptibility where closely related Asian, European and North American species in section Fraxinus had relatively high levels of H. fraxineus DNA in the leaves and supported high production of apothecia. Leaves from some North American species also contained relatively high levels of H. fraxineus DNA, supported moderate production of apothecia and developed lesions—stating the need to avoid introduction of H. fraxineus to North America.     

Effect of oriental armyworm <Emphasis Type="Italic">Mythimna separata</Emphasis> egg age on the parasitism and host suitability for five <Emphasis Type="Italic">Trichogramma</Emphasis> species

The oriental armyworm Mythimna separata (Walker) is a major cereal crop pest, causing severe economic losses worldwide every year. Yet, few studies documented the biological control of M. separata using natural enemies such as egg parasitoids of the genus Trichogramma. To evaluate the possibility of biological control of M. separata eggs at various ages (0-, 1-, 2-, and 3-day old), we compared under laboratory conditions the parasitism, emergence, development, and female progeny (sex ratio) of five Trichogramma species indigenous in China: Trichogramma dendrolimi Matsumura, T. chilonis Ishii, T. ostriniae Pang & Chen, T. leucaniae Pang & Chen, and T. japonicum Ashmend. All five Trichogramma species parasitized M. separata at all egg ages but showed a preference for younger eggs. T. dendrolimi parasitized 55.1, 36.6, 19.3, and 14.3 hosts in 24 h on 0-, 1-, 2-, and 3-day-old eggs, respectively, and it exhibited the highest parasitism and suitability on all egg ages. T. japonicum showed the lowest parasitism rate and the poorest host acceptance. T. ostriniae, T. leucaniae, and T. chilonis presented similar rates of adult emergence and sex ratio for all M. separata egg ages. T. ostriniae developed significantly slower on 2- and 3-day-old M. separata eggs. With the exception of T. leucaniae, all species showed no difference in adult emergence at all egg ages. T. dendrolimi was identified as the best for biological control of M. separata. The present study provides valuable information for future development of Trichogramma species in biological control programs targeting M. separata as pest.     

Descriptions of <Emphasis Type="Italic">Leptomastidea angulipennis</Emphasis> sp. nov. and two known species of <Emphasis Type="Italic">Leptomastidea</Emphasis> (Hymenoptera: Encyrtidae), with a key to Chinese species

Leptomastidea angulipennis sp. nov. is described as new to science from Yunnan, China. It can be easily separated from all the other species of the genus by the triangular shape and infuscate pattern of the forewing. Brief diagnoses and new distributional data of L. herbicola and L. rubra are also provided, and a key to the females of all the Chinese species is given.     

Identification and evaluation of reference genes for normalization in quantitative real-time PCR analysis in the premodel tree <Emphasis Type="Italic">Betula luminifera</Emphasis>

Betula luminifera is a commercial tree species that is emerging as a new model system for tree genomics research. A draft genomic sequence is expected to be publicly available in the near future, which means that an explosion of gene expression studies awaits. Thus, the work of selecting appropriate reference genes for qPCR normalization in different tissues or under various experimental conditions is extremely valuable. In this study, ten candidate genes were analyzed in B. luminifera subjected to different abiotic stresses and at various flowering stages. The expression stability of these genes was evaluated using three distinct algorithms implemented using geNorm, NormFinder and BestKeeper. The best-ranked reference genes varied across different sample sets, though RPL39, MDH and EF1a were determined as the most stable by the three programs among all tested samples. RPL39 and EF1a should be appropriate for normalization in N-starved roots, while the combination of RPL39 and MDH should be appropriate for N-starved stems and EF1a and MDH should be appropriate in N-starved leaves. In PEG-treated (osmotic) roots, MDH was the most suitable, whereas EF1a was suitable for PEG-treated stems and leaves. TUA was also stably expressed levels in PEG-treated plants. The combination of RPL39 and TUB should be appropriate for heat-stressed leaves and flowering stage. For reference gene validation, the expression levels of SOD and NFYA-3 were investigated. This work will be beneficial to future studies on gene expression under different abiotic stress conditions and flowering status in B. luminifera.     

Effects of <Emphasis Type="Italic">Verticillium nonalfalfae</Emphasis> on <Emphasis Type="Italic">Ailanthus altissima</Emphasis> and associated indigenous and invasive tree species in eastern Austria

The naturally occurring Verticillium nonalfalfae shows promise for biocontrol of the highly invasive Tree of Heaven (Ailanthus altissima), but might also bear a risk for non-target tree species. In this study, we conducted inoculations on potted seedlings of A. altissima as well as on eight indigenous and two invasive tree species associated with Tree of Heaven in Austria. Although vascular discolourations developed in all inoculated tree species, V. nonalfalfae was reisolated from Ailanthus and eight of the ten non-target-species, whereas typical disease symptoms and mortality only occurred on A. altissima. Results confirmed high susceptibility (S) of A. altissima to V. nonalfalfae but indicated tolerance (T) of Acer campestre, Acer pseudoplatanus and Quercus robur, possible resistance (PR) of Fraxinus excelsior, Populus nigra, Tilia cordata, Ulmus laevis and Ulmus minor and resistance (R) of Fraxinus pennsylvanica and Robinia pseudoacacia to this potential biocontrol agent. Results from seedling inoculations were confirmed by cursory field observations in Ailanthus-inoculated forest stands, where admixed A. campestre, A. pseudoplatanus, F. excelsior, Populus alba, R. pseudoacacia and U. laevis canopy trees remained asymptomatic, while mortality was induced in Ailanthus.     

<Emphasis Type="Italic">Santalum</Emphasis> molecular biology: molecular markers for genetic diversity,phylogenetics and taxonomy,and genetic transformation

Species of the Santalum genus are well known for their fragrant hardwood, which has great value in medicinal, pharmaceutical and cosmetic industries. Sandalwood oil is derived from the heartwood of Santalum sp. and contains α-, β- and epi-β-santalols, which are responsible for its pleasant fragrance. Oil content can vary from species to species. Pressure on natural populations due to habitat loss, legal and illegal harvesting and disease is increasing. This paper highlights the development of molecular markers for the refinement of phylogenetic studies, identification of various Santalum and adulterant species, assessment of genetic diversity, genetic differentiation, clonality and management units within species, and for marker-assisted breeding. The identification of quantitative trait loci for sandal spike disease and for other traits such as specific rare secondary metabolites in the essential oil and related to its fragrance, would also benefit from molecular advances. RNA sequence analyses have already identified changes in gene expression and metabolic pathways in developing Santalum album L. haustoria.     

ISSR and SSR markers reveal sex-specific DNA sequences in three <Emphasis Type="Italic">Calamus</Emphasis> species from India

Calamus species yields the raw materials for the cane industry. However, the extraction of the cane from the forests is being carried out indiscriminately without considering the sustenance of the species. Plants of both sexes should co-exist for reproductive success. The sex of Calamus plants can be identified only after flowering and hence proper planning of managed forestry practices cannot be accomplished. A study was carried out in this background and male specific ISSR markers for C. tenuis and C. flagellum and SSR markers for C. thwaitesii were identified. The diagnostic potential of these markers can be exploited to sex the Calamus species at the seedling stage for proper breeding and agroforestry management.     

Pentatomid host suitability and the discovery of introduced populations of <Emphasis Type="Italic">Trissolcus japonicus</Emphasis> in Oregon

Trissolcus japonicus is an egg parasitoid of Halyomorpha halys, brown marmorated stink bug, a severe agricultural pest in the USA. T. japonicus is being evaluated in quarantine as a classical biological control agent to manage H. halys populations in the USA. To determine T. japonicus’ potential for successful management of the pest, we performed a series of no-choice and paired-host-range tests, evaluating parasitism and host recognition in ten nontarget insects. In laboratory no-choice tests, T. japonicus successfully parasitized egg masses of seven Pentatomidae native to Oregon in addition to H. halys. Mean parasitism proportions of egg masses were greater than 40% in two species, B. dimidiata and H. abbreviatus, and were statistically similar to parasitism of H. halys. However, paired-host tests identified higher proportions of parasitized H. halys egg masses compared to four other pentatomids. T. japonicus was equally attracted to volatiles produced by H. halys and other pentatomids but demonstrated significantly longer arrestment response time on surfaces with H. halys contact kairomones. Although host acceptance patterns were similar between stink bug species, our results suggest a greater potential for parasitoid development in H. halys eggs compared to the native pentatomids. During host-range testing, we detected field populations of T. japonicus at 11 sites in Portland, OR, indicating an unintentional introduction and establishment. Further work is needed to characterize its nontarget activity and dispersal patterns in areas where H. halys causes economic damage in Oregon.     

Natural biological control of <Emphasis Type="Italic">Halyomorpha halys</Emphasis> by native egg parasitoids: a multi-year survey in northern Delaware

Halyomorpha halys (Stål) is a highly polyphagous plant pest native to eastern Asia. Since its accidental introduction to the USA in the mid-1990s, it has spread across North America and caused serious economic damages. Chemical control has been a widely applied management strategy which is not sustainable on a long-term basis. A nine-year survey using sentinel and naturally laid H. halys was conducted to investigate the extent of natural biological control by parasitoids in managed and non-managed landscapes in northern Delaware, USA. Naturally laid egg masses of native pentatomids were collected to compare the resident parasitoid complex to the one attacking H. halys eggs. Mean parasitism rates of sentinel eggs were below 6% in any given year of the survey with a grand mean of 1.79%. Parasitism of naturally laid H. halys eggs was higher than that of sentinel eggs, but there was no significant difference in parasitism between years and the grand mean was 4.31%. Parasitoid species richness on sentinel and naturally laid H. halys eggs was similar but both were lower than the richness on native pentatomid eggs. H. halys eggs were parasitized by eight species in the genera Anastatus, Trissolcus, Telenomus, and Ooencyrtus. The level of parasitism by native egg parasitoids is insufficient to provide long-term control of H. halys. Trissolcus japonicus (Ashmead), an Asian egg parasitoid that has been recovered in the USA in several locations since 2014, may be the most promising candidate for long-term biological control of H. halys.     

Genetic diversity and population structure analysis of <Emphasis Type="Italic">Pistacia</Emphasis> species revealed by <Emphasis Type="Italic">phenylalanine ammonia</Emphasis>-<Emphasis Type="Italic">lyase</Emphasis> gene markers and implications for conservation

Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon’s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei’s genetic distance and genetic identity between populations revealed a close association between geographically isolated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among-population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species.     

Effects of <Emphasis Type="Italic">Eucalypt</Emphasis> and <Emphasis Type="Italic">Acacia</Emphasis> plantations on soil water in Sumatra

Indonesia’s pulp and paper industry needs a large area of sustainably grown plantations to support its continued development. Acacia mangium has been the key species underpinning the pulp and paper industries in Sumatra, however increased disease pressure on A. mangium is expected to require large-scale conversion of Acacia plantations to Eucalyptus in the near future. The effect of such a large scale change in plantation species on soil moisture, for both tree production, and catchment hydrology is unknown. In this study we sought to characterize the impacts of plantation species (Acacia or Eucalyptus) and nitrogen management, on soil moisture, soil water depletion and depth to groundwater under stands of Acacia mangium and Eucalyptus pellita over the first 2–3 years after establishment. The study was conducted in experiments at four sites in Sumatra, Indonesia. Soil moisture and soil water depletion were not influenced by plantation species or fertilizer treatment. Soil moisture content and soil water depletion were strongly influenced by shallow groundwater at two of the four sites, however depth to groundwater did not influence stem growth. Results from the field trials cautiously suggest that large scale conversion of Acacia mangium to Eucalypt species in these regions is unlikely to result in increased moisture stress, nor is conversion of plantation species likely to lead to substantial differences in catchment hydrology. This study demonstrated the importance of conducting multi-site studies when investigating biophysical relationships in forest/plantation systems.     

Contributions to the knowledge of conifer aphid fauna in Turkey and their zoogeographical distribution

The Aphidoidea (Homoptera) has 29 species which attack coniferous trees in Turkey. The family Aphididae has 25 (Aphidinae, 1; Lachninae, 22; Mindarinae, 2) species and the Adelgidae, 4. The tribe Cinarini in Lachninae has alone 22 species most of which are important. Especially Cinara cedri Mimeur on Cedrus libani and C. pilicornis (Hartig) on Picea spp. are harmful species. Schizolachnus pineti (Fabricius) is also very important. An Eastern Palearctic species in the tribe Macrosiphini in Aphidinae, Elatobium momii (Shinji), is numerous on Abies bornmülleriana in Bursa-Uluda? forests. Pineus orientalis (Dreyfus) in the family of Adelgidae (Chermesidae) is the most destructive in our Picea orientalis forests in Artvin area (Eastern Black-Sea Section). 21 species out of 29 aphids on coniferous trees are of European origin; only 4 are Mediterranean, 2 Caucasus and Turkistan, one Eastern Palearctic and one of Cosmopolitan origin.     

Seasonal parasitism and host specificity of <Emphasis Type="Italic">Trissolcus japonicus</Emphasis> in northern China

The brown marmorated stink bug, Halyomorpha halys (Stål), native to China, Japan, and Korea, has emerged as a harmful invasive pest of a variety of crops in North America and Europe. The Asian egg parasitoid Trissolcus japonicus has been identified as the most promising agent for classical biological control of invasive H. halys populations. A 4-year study evaluated the fundamental and ecological host ranges of T. japonicus as well as its phenology and impact on H. halys populations in fruit orchards in its native range in northern China. In laboratory no-choice tests, developmental suitability of eight non-target host species for T. japonicus was demonstrated by the successful production of progeny on the majority (>85%) of non-target host species tested. In field-collected, naturally laid egg masses, T. japonicus was the most abundant parasitoid associated with H. halys and Dolycoris baccarum, but was also sporadically found in Plautia crossota. Furthermore, it was regularly reared from sentinel egg masses of Menida violacea, Arma chinensis, and Carbula eoa. The only species that did not support development in the laboratory and field was Cappaea tibialis. Besides the benefit of having a high impact on H. halys populations in Northern China, the risk assessment conducted in the area of origin indicates that native Pentatomidae in North America and Europe could be negatively impacted by T. japonicus. Whether the benefits of T. japonicus outweigh the possible risks will have to be evaluated based on the outcome of additional host range studies in the two invaded regions.     

Effect of light,fire and weed control on establishment of <Emphasis Type="Italic">Pericopsis elata</Emphasis> Harms regeneration

Pericopsis elata (a.k.a. African teak) is one of the most valuable timber species in Central Africa. Like other shade intolerant tropical tree species, P. elata could play a vital role in economic development, and ecological sustainability, but regenerates poorly following selective logging. Now endangered, there is a critical need for sustainable silvicultural systems to restore this once prominent timber species. To assess management options for P. elata we analyzed growth performance and survival in primary and secondary forest plots under burning and weeding treatments in Yoko Forest Reserve, Ubundu Democratic Republic of Congo. We transplanted nursery-grown seedlings of P. elata to experimental gaps and followed their growth and survival for 1 year. Seedlings in large canopy gaps 50 × 50 m were taller (mean difference; P = 0.006) and more likely to survive (mean difference; P < 0.001). Weeding improved both diameter (P = 0.024) and height (P = 0.007) growth rates; however, burning alone did not significantly improve the performance of P. elata seedlings. Our data suggest that P. elata regeneration is compatible with shelterwood harvesting and traditional swidden agricultural systems widely practiced in the region.     

Phylogenetic relationships among five species of <Emphasis Type="Italic">Armeniaca</Emphasis> Scop. (Rosaceae) using microsatellites (SSRs) and capillary electrophoresis

The genus Armeniaca Scop. is well known for its popular cultivated edible fruit trees such as Armeniaca vulgaris Lam. and ornamental flowers such as A. mume Sieb. Another species, A. cathayana Fu et al., one of six important dry fruits (kernel-using apricot), is cultivated for its edible seeds in North China. In the present study, DNA from 70 individuals of Armeniaca, including 38 of A. cathayana, 18 of A. vulgaris, 12 of A. sibirica, 1 of A. dasycarpa and 1 of A. mume, was extracted and analyzed using microsatellites and capillary electrophoresis. For 20 polymorphic loci selected, 339 alleles and 140.7 effective alleles were detected. The number of alleles per locus ranged from 8 to 28, with an average of 16.95 alleles per locus. The observed heterozygosity (Ho) and the expected heterozygosity (He) ranged from 0.427 to 0.971 and from 0.737 to 0.912, respectively. The polymorphism information content varied from 0.708 to 0.905, with an average of 0.827. Based on the genetic similarity among 70 individuals, a UPGMA was used to establish the phylogenetic relationships. The taxonomic positions among five species were clearly revealed, and A. cathayana was more closely related to A. vulgaris than to A. sibirica. The results will provide a scientific basis for research on the taxonomy, germplasm resources and breeding of Armeniaca, especially for A. cathayana.     

中国东北林区桦木属（Betula）分类探讨

许多学者先后对东北林区桦木属的分类进行了深入研究,对种及种下分类等级意见至今不一致,给综合开发利用桦木类群资源造成了混乱。笔者经多年深入林区实践、调查、采集标本,结合种群特征、地理分布、生境特点综合分类,不以蜡叶标本作为唯一依据,鉴定了桦木属种及种下等级,基本上同意傅沛云(1995)对东北林区桦木属的分类。但笔者认为东北白桦(B.mandshurica(Regel) Nakai)应视为独立种,取消栓皮白桦(Betula platyphylla Suk.var. phellodendroides Tung)名称及英吉里岳桦(ermanii Cham.var.yingkiliensis liou et Wang)名称,卵叶桦(Betula ovalifolia Rupr )不应该降为柴桦变种(Betula fruticosa Pall.),仍为独立种。图1表4参10。