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1.
The Asian walnut moth, Garella musculana (Erschov, 1874) (Lepidoptera: Nolidae), is a major pest of walnut. Native to Central Asia, it was found to be invasive in 2008 in Sevastopol (Crimea) and nowadays widespread in Turkey, Bulgaria, Romania and Russia. Here, we account for the finding of G. musculana in NE Italy (Veneto region) in 2021, where adults were found in a light lamp, representing the first record of the Asian walnut moth for this country and Western Europe. Adult specimens were identified morphologically on both external characters and genitalia features. G. musculana larvae and damage were also observed on a plantation of Juglans regia L. (Fagales: Juglandaceae) located in Veneto in October 2021. A COI-barcoding analysis was performed to attain a molecular characterization of our specimens and probate our morphological identification. However, because no sequence of G. musculana was present in major gene databases and the similarity of our sequences with those attributed to Garella ruficirra (Hampson, 1905) (Lepidoptera: Nolidae) made clear that these taxa deserved further scrutiny regarding their specific distinction. Some subtle differences in the male terminalia could be found between them and their vast geographic distributions, but the strong similarity in most features calls for further morphological and genetical insights on a broad set of samples to assess whether they represent two closely related, substantially parapatric species, or a unique, geographically varying entity. Solving this issue may turn out crucial in the identification and proper management of walnut moths of the genus Garella.  相似文献   
2.
通过对新疆野核桃自然保护区丛生野核桃(Juglans regia)进行普查,以径级结构代替年龄结构,采用匀滑技术编制种群静态生命表,并运用时间序列模型预测种群数量动态,从而获得丛生野核桃树的龄级结构与动态。结果表明,不同坡向丛生野核桃以中龄级为主,年龄结构呈两头小中间大的纺锤型;4个坡向种群年龄结构的动态指数Vpi虽大于0,但最大仅为19.10%,且Vpi’极低,最大为1.12%,阳坡种群增长趋势最高,抗干扰能力最强,种群稳定性最好,半阳坡种群增长趋势最弱,抗干扰能力最弱,种群稳定性最差;各坡向种群均存在多个死亡高峰,阳坡最高峰在15龄级,半阳坡在15和18龄级,阴坡和半阴坡均在9龄级,存活曲线更接近Deevey-Ⅱ型;在未来2、5、10龄级后,中龄级个体数量减少,老龄个体呈增加趋势,丛生野核桃种群稳定性难以长期维持。因此对丛生野核桃幼苗的保护非常关键。  相似文献   
3.
Preplanting treatment of soil naturally infested with Macroposthonia xenoplax with 1,2-dibromoethane (ethylene dibromide) significantly increased the growth rate of Juglans hindsii seedlings. When seedlings of J. hindsii, J. regia CV "Serf" and J. regia CV Eureka were inoculated with M. xenoplax, their growth was signilicantly less than that of nematode-free controls. This retarded growth rate was accompanied hy feeder root necrosis, longitudinal cracks in the older roots, and distinct lesions in the secondary phloem.  相似文献   
4.
Walnut decline caused by Phytophthora sp. occurred in an orchard in Sakarya province in Turkey. Affected young trees showed poor growth, leaf discolouration, root and crown rot and eventual death. A Phytophthora sp. isolated from necrotic taproots and crown tissues. The causal agent of the disease was identified as Phytophthora cinnamomi by morphological characteristics and comparing sequences of internal transcribed spacer (ITS) region. Upon conducting pathogenicity test, averaging 7.8‐cm‐long canker developed on basal stem within 2 weeks, while no cankers developed in the control plants.  相似文献   
5.
目的研究胡桃楸提取物对白念珠菌生物膜形成的影响。方法采用甲基四氮盐(XTT)还原法评价胡桃楸提取物对白念珠菌的生物膜形成及黏附性的影响。镜下观察胡桃楸提取物对白念珠菌生物膜的形态学影响。结果胡桃楸提取物抑制白念珠菌生物膜50%及90%的最小抑制药物浓度(SMIC50、SMIC90)分别为15.2μg、23.4μg。胡桃楸提取物作用浓度大于20μg时对该菌细胞黏附有抑制作用。30μg胡桃楸提取物可完全抑制白念珠菌生物膜的形成。结论胡桃楸提取物对体外白念珠菌生物的膜形成有较强的抑制作用。  相似文献   
6.
Phytochemical research of different polarity extracts from green Juglans regia L. pericarps from Greece afforded 32 compounds: four pentacyclic triterpenes (1 – 4), three sesquiterpenes (5 – 7), four tetralones (8 – 11), two naphthoquinones (12 and 13), seven phenolic acids (14 – 20), one diarylheptanoid (21), one neo‐lignan (22), seven flavonoids (23 – 29), two phenylethanoids (30 and 31) and one hydrolysed tannin (32). Compounds 4 and 29 are isolated for the first time from the species, while compounds 3, 7, 20, 22, 23, 24, 25, 26, 28, 30 are reported for the first time in Juglandaceae. Chemotaxonomic significance of isolated compounds into Junglandaceae family is thoroughly discussed.  相似文献   
7.
病程相关基因非表达子NPR1(Nonexpressor of pathogenesis-related gene 1)基因,在植物抗病过程中起核心调控作用。核桃(Juglans regia)是我国乡村振兴的重要经济油料树种,其生长和产量严重受病虫害制约。为探索核桃抗病生理机制,筛选抗病基因,以‘香玲’核桃为试材,克隆获得JrNPR1基因,对其基本生物信息和病害响应进行分析,预测JrNPR1响应病害的功能。结果显示:JrNPR1基因开放读码框(ORF)长1 782 bp,包含593个氨基酸,理论等电点为6.40;与杨梅(Morella rubra)、蓖麻(Ricinus communis)等同源蛋白进行多序列比对,发现均有NPR1-like-C保守结构域,且JrNPR1与杨梅和欧洲栓皮栎(Quercus suber)等的同源蛋白具有较近的进化关系。其上游1 233 bp启动子中含有多种与植物抗病相关的顺式作用元件,如,WRKY71OS。在胶孢炭疽菌(Colletotrichum gloeosporioides)、矩圆黑盘孢菌(Melanconium oblongum)、黄单胞菌(Xanthomonas campestris)等病原处理下,JrNPR1被显著诱导,且其表达在水杨酸(Salicylic acid,SA)存在下高出单一病原处理的1.31~178.89倍。表明JrNPR1基因可能是抵抗核桃炭疽病、枝枯病、细菌性黑斑病的重要基因,且涉及SA信号通路。  相似文献   
8.
Architectural analysis of 840 Slovenian walnut (Juglans regia L.) genotypes was performed to determine the most typical and frequent morphological types and to evaluate their vegetative and generative potential. Four branching and fruiting patterns (I-IV) were detected. A 3-year-old fruiting branch, consisting of a 3-year-old shoot plus corresponding 2-year-old and 1-year-old shoots, was used as a structural unit for quantitative analysis. In the intermediate fruit-bearing types with mesotonic and acrotonic branching pattern (types II and III), the total lengths of 3-, 2- and 1-year-old shoots were 385 and 380 cm, respectively, compared with 275 and 253 cm in the terminal and lateral-fruiting types (types I and IV). In type I, 1-year-old shoots had significantly fewer nodes than in other types. In addition, they had a thinner basal diameter than types III and IV, and their angles were the most erect (39 degrees ). Only 0.4 out of 3.6 1-year-old shoots were flowering with one mixed bud with 1.9 female flowers. In type IV, 2-year-old shoots had significantly more nodes and a larger basal diameter than other types. One-year-old shoots in type IV are thicker than those in other types. Ratios between the number of flowering and the total number of 1-year-old shoots were 0.7 in type IV, 0.6 in type III, 0.5 in type II and 0.1 in type I. On 1-year-old shoots in type IV, 1.7 mixed buds with a mean of three female inflorescences per bud were counted. Consequently, the generative potential is highest in type IV and lowest in type I. In types II and III, growth and the ability to bear fruits are more balanced.  相似文献   
9.
Juglans mandshurica is an economically and ecologically valuable species that is used for various construction purposes, making luxurious furniture, as food and sources of medicinal substances and landscaping because of its excellent wood, edible fruits and rich in various types of chemical compounds. In the past few decades, several genetic improvements of J. mandshurica were made, with a focus on the selection of improved varieties and on breeding technology. Many elite provenances and families were selected based on growth traits or wood properties. In recent years, with the increasing demand for high-quality seedlings in Chinese forestry production, the breeding goals of genetic improvement for J. mandshurica were redefined to include other traits, such as fruit yield and contents of medicinal component. However, the improvement processes were still slow due to the long breeding cycle and the limited use of advanced breeding technologies, resulting in the selection of fewer improved varieties. In this review, we summarized the research progresses on genetic improvements of J. mandshurica and other related works, and discussed research gaps and suggested future directions for genetic improvement of the species. The review provides valuable insight for the selection of improved varieties and production of excellent germplasms.  相似文献   
10.
Climate change effects on walnut pests in California   总被引:1,自引:0,他引:1  
Increasing temperatures are likely to impact ectothermic pests of fruits and nuts. This paper aims to assess changes to pest pressure in California's US$0.7 billion walnut industry due to recent historic and projected future temperature changes. For two past (1950 and 2000) and 18 future climate scenarios (2041–2060 and 2080–2099; each for three General Circulation Models and three greenhouse gas emissions scenarios), 100 years of hourly temperature were generated for 205 locations. Degree‐day models were used to project mean generation numbers for codling moth (Cydia pomonella L.), navel orangeworm (Amyelois transitella Walker), two‐spotted spider mite (Tetranychus urticae Koch), and European red mite (Panonychus ulmi Koch). In the Central Valley, the number of codling moth generations predicted for degree days accumulated between April 1 and October 1 rose from 2–4 in 1950 to 3–5 among all future scenarios. Generation numbers increased from 10–18 to 14–24 for two‐spotted spider mite, from 9–14 to 14–20 for European red mite, and from 2–4 to up to 5 for navel orangeworm. Overall pest pressure can thus be expected to increase substantially. Our study did not include the possibility of higher winter survival rates, leading to higher initial pest counts in spring, or of extended pest development times in the summer, factors that are likely to exacerbate future pest pressure. On the other hand, initiation of diapause may prevent an extension of the season length for arthropods, and higher incidence of heat death in summer may constrain pest population sizes. More information on the impact of climate change on complex agroecological food webs and on the response of pests to high temperatures is needed for improving the reliability of projections.  相似文献   
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