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Pistil abortions of flower buds occur frequently in many apricot cultivars, especially in long branches. However, the molecular mechanism underlying pistil abortion in apricots remains unclear. To better understand the molecular mechanism of pistil abortions between long branches and spur twigs, paraffin sections and high-throughput sequencing technology were employed to analyze the expression patterns of genes associated with pistil abortions during later flower bud development stage in 'Shajinhong' apricot. The result of stage III (separation of bud scales) was the critical stage of pistil abortion in apricots. A total of 163 differentially expressed genes were identified as candidate genes related to pistil abortion in long branches. These genes are implicated in programmed cell death, hormone signaling, cell wall degeneration, and the carbohydrate metabolism pathway. The results showed that the up-regulation of gene expression of Xyloglucan endotransglucosylase/hydrolase and β-glucosidase in flower buds might be the direct cause of cell wall breakdown and pistil necrosis in long branches. We hypothesize that there is a molecular relationship between pistil abortion before blooming and cellulose degradation, and then carbohydrate transport in the case of carbon deficiency in long branches. Our work provides new insights into cellulose degradation in abortion pistils and valuable information on flower development in apricots, and also provides a useful reference for cultivation regulation in apricot or other fruit crops. [ABSTRACT FROM AUTHOR]

Woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann), is an important global pest that feeds on Malus species. We studied the feeding preference of WAA on apple trees in the field for two consecutive years and in the laboratory we used electronic penetration graphs (EPG) to record the stylet penetration behavior of WAA on different parts of apple trees. We found that in the field WAA fed primarily on twigs and branches, not on leaves and fruits. Six EPG waveforms were produced during WAA probing on shoots, trunks and leaves of apple trees, including the non-penetration wave (np), the stylet pathway phase wave (C), the intracellular feeding wave (pd), the xylem feeding wave (G), waves indicative of release of saliva into the phloem (E1), and a wave indicative of ingestion from phloem (E2). In the laboratory, aphids only successfully fed on shoots, trunks and leaves, not on fruits. The EPG parameters on the phloem of shoots were significantly higher than those on trunks, indicating WAA prefer to feed on shoots. These laboratory findings explain the relative field feeding preference of WAA on different parts of apple trees, which occurs primarily on branches, barks, and young twigs in orchards, especially on young twigs. [ABSTRACT FROM AUTHOR]

EtOH extracts from the leaves and twigs of Nectandra oppositifolia Nees & Mart. shown activity against amastigote forms of Trypanosoma cruzi. These extracts were subjected to successive liquid-liquid partitioning to afford bioactive CH2Cl2 fractions. UHPLC-TOF-HRMS/MS and molecular networking were used to obtain an overview of the phytochemical composition of these active fractions. Aiming to isolate the active compounds, both CH2Cl2 fractions were subjected to fractionation using medium pressure chromatography combined with semi-preparative HPLC-UV. Using this approach, twelve compounds (1–12) were isolated and identified by NMR and HRMS analysis. Several isolated compounds displayed activity against the amastigote forms of T. cruzi, especially ethyl protocatechuate (7) with EC50 value of 18.1 μM, similar to positive control benznidazole (18.7 μM). Considering the potential of compound 7, protocatechuic acid and its respective methyl (7a), n-propyl (7b), n-butyl (7c), n-pentyl (7d), and n-hexyl (7e) esters were tested. Regarding antitrypanosomal activity, protocatechuic acid and compound 7a were inactive, while 7b-7e exhibited EC50 values from 20.4 to 11.7 μM, without cytotoxicity to mammalian cells. These results suggest that lipophilicity and molecular complexity play an important role in the activity while efficiency analysis indicates that the natural compound 7 is a promising prototype for further modifications to obtain compounds effective against the intracellular forms of T. cruzi. [ABSTRACT FROM AUTHOR]

Phasmatodea represents an order of hemimetabolous insects. This group includes species with extreme forms of masquerade crypsis, whereby they imitate twigs, bark, lichen, moss, and leaves. In this study, we sequenced and annotated three mitochondrial genomes (mitogenomes) from Phasmatodea. The lengths of the novel mitogenomes range from 14,162 bp to 15,879 bp. The gene content and organization correspond to those inferred for the ancestral insect. We conducted phylogenetic analyses together with the existing mitogenomes of polyneopterans and mayflies. In most cases, the Phasmatodea was non-monophyletic, with Embioptera and Zoraptera nested inside. The mitogenome sequences from Embioptera and Zoraptera suffered from high substitution rates and displayed very long branches in phylogenetic trees. The monophyletic Phasmatodea was recovered only when the analysis employed the site-heterogeneous CAT-GTR model in PhyloBayes and used the nucleotide dataset PCG_nt. The Euphasmatodea was well established by various data types and inference methods. In addition, the clade Heteropterygidae and the subfamilies Lonchodinae and Necrosciinae were strongly supported. The Australasian clade Lanceocercata was recovered across analyses. However, the Clitumninae was non-monophyletic. [ABSTRACT FROM AUTHOR]

Aranbaltza is an archaeological complex formed by at least three open-air sites. Between 2014 and 2015 a test excavation carried out in Aranbaltza III revealed the presence of a sand and clay sedimentary sequence formed in floodplain environments, within which six sedimentary units have been identified. This sequence was formed between 137–50 ka, and includes several archaeological horizons, attesting to the long-term presence of Neanderthal communities in this area. One of these horizons, corresponding with Unit 4, yielded two wooden tools. One of these tools is a beveled pointed tool that was shaped through a complex operational sequence involving branch shaping, bark peeling, twig removal, shaping, polishing, thermal exposition and chopping. A use-wear analysis of the tool shows it to have traces related with digging soil so it has been interpreted as representing a digging stick. This is the first time such a tool has been identified in a European Late Middle Palaeolithic context; it also represents one of the first well-preserved Middle Palaeolithic wooden tool found in southern Europe. This artefact represents one of the few examples available of wooden tool preservation for the European Palaeolithic, allowing us to further explore the role wooden technologies played in Neanderthal communities. [ABSTRACT FROM AUTHOR]

Understanding the response of biomass allocation in twigs (the terminal branches of current-year shoots) to environmental change is crucial for elucidating forest ecosystem carbon storage, carbon cycling, and plant life history strategies under a changing climate. On the basis of interspecies investigations of broad-leaved plants, previous studies have demonstrated that plants respond to environmental factors by allocating biomass in an allometric manner between support tissues (i.e., stems) and the leaf biomass of twigs, where the scaling exponent (i.e., slope of a log—log linear relationship, α) is constant, and the scaling constant (i.e., intercept of a log—log linear relationship, log β) varies with respect to environmental factors. However, little is known about whether the isometric scaling exponents of such biomass allocations remain invariant for single species, particularly conifers, at different altitudes and in different growing periods. In this study, we investigated how twig biomass allocation varies with elevation and period among Pinus hwangshanensis Hsia trees growing in the mountains of Southeast China. Specifically, we explored how twig stem mass, needle mass, and needle area varied throughout the growing period (early, mid-, late) and at three elevations in the Wuyi Mountains. Standardized major axis analysis was used to compare the scaling exponents and scaling constants between the biomass allocations of within-twig components. Scaling relationships between these traits differed with growing period and altitude gradient. During the different growing periods, there was an isometric scaling relationship, with a common slope of 1.0 (i.e., α ≈ 1.0), between needle mass and twig mass (the sum of the total needle mass and the stem mass), whereas there were allometric scaling relationships between the stem mass and twig mass and between the needle mass and stem mass of P. hwangshanensis. The scaling constants (log β) for needle mass vs. twig mass and for needle mass vs. stem mass increased progressively across the growing stages, whereas the scaling constants of stem mass vs. twig mass showed the opposite pattern. The scaling exponents (α) of needle area with respect to needle biomass increased significantly with growing period, changing from an allometric relationship (i.e., α < 1.0) during the early growing period to a nearly isometric relationship (i.e., α ≈ 1.0) during the late growing period. This change possibly reflects the functional adaptation of twigs in different growing periods to meet their specific reproductive or survival needs. At different points along the altitudinal gradient, the relationships among needle mass, twig mass, and stem mass were all isometric (i.e., α ≈ 1.0). Moreover, significant differences were found in scaling constants (log β) along the altitudinal gradient, such that species had a smaller stem biomass but a relatively larger needle mass at low altitude. In addition, the scaling exponents remained numerically invariant among all three altitudes, with a common slope of 0.8, suggesting that needle area failed to keep pace with the increasing needle mass at different altitudes. Our results indicated that the twig biomass allocation pattern was significantly influenced by altitude and growing period, which reflects the functional adaptation of twigs to meet their specific survival needs under different climatic conditions. [ABSTRACT FROM AUTHOR]

The community of endophytic fungi associated with Acer ginnala, a common tree in northeastern China, was investigated. Four media, PDA, Czapek's, WA and Sabouraud's, were used to inoculate explants from seeds, annual twigs and perennial twigs (xylem and bark). Media strongly affected the isolated species number, but not colonization frequency (CF) or isolation frequency (IF). To investigate media effect further, a Principal Component Analysis (PCA) was done. As a result, two components accounted for 86.502% of the total variance were extracted. These two components were named as PDA-determined factor (accounted for 45.139% of the total variance) and Czapek's-determined factor (accounted for 41.363% of the total variance), respectively. This result suggested that only two media, PDA and Czapek's, could be used instead of all four media in this study without affecting the isolation results significantly. In total, ten taxa were isolated in this study. Alternaria sp., Phomopsis sp., Neurospora sp. and Phoma sp. were dominant endophytes while Pleosporales Incertae Sedis sp., Cladosporium sp., Trichoderma sp. and Epicoccum sp. were rare taxa. Different tissues/organs had different endophyte assemblages. All tissue/organ pairs had low Bray-Curtis indices (<0.3) except for bark and annual twigs (0.63). Compared to perennial twigs, annual twigs had a lower taxon number, lower isolate number, lower endophyte dominance and diversity indices. Seeds had distinct assemblage, lower similarity and similar low diversity indices to annual twigs. These results suggested that tissue type determines the endophyte assemblage while age determines the diversity. [ABSTRACT FROM AUTHOR]