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1.
Wheat stem rust, caused by the fungus Puccinia graminis f. sp. tritici (Pgt), is a notoriously damaging disease of wheat and barley. Pgt requires two hosts to complete its lifecycle; undergoing asexual reproduction on cereal crops and completing sexual reproduction on Berberis spp. The latter stage of its lifecycle is of particular importance in temperate regions such as western Europe, where asexual urediniospores are unable to survive cold winter weather. In the past, the crucial role of Berberis in the lifecycle of stem rust led to intensive eradication campaigns, initially carried out by farmers in the face of hostile scientific opinion. In the United Kingdom, common barberry (Berberis vulgaris) is today a relatively rare plant. Stem rust is, however, currently experiencing a resurgence; at the same time, there has been a general increase in the prevalence of barberry and an upsurge in its planting which, in the United Kingdom, is associated with attempts to encourage the endangered barberry carpet moth (Pareulype berberata). This article situates current developments within a broader chronological framework, examining changing attitudes towards barberry and rust in England in the past and the history of the plant's use and cultivation. It assesses how widespread B. vulgaris really was in the environment historically, and thus the scale of its eradication. We suggest that Berberis was never widely established as an archaeophyte in the United Kingdom. Current attempts to re-establish it are based on a misunderstanding of the plant's historical status and could potentially pose a serious threat to food security. 相似文献
2.
vvi-miR160s介导VvARF18应答赤霉素调控葡萄种子的发育 总被引:1,自引:0,他引:1
【目的】研究vvi-miR160家族(vvi-miR160s)及其靶基因在‘魏可’葡萄种子发育过程中的作用,探究其应答赤霉素(GA)调控葡萄果实无核的潜在机理。【方法】采用miR-RACE、生物信息学分析、RT-qPCR、RLM-RACE等方法,鉴定vvi-miR160家族成员及其靶基因,分析vvi-miR160s及其靶基因应答GA的时空表达模式及其潜在功能。【结果】花前GA处理强烈抑制‘魏可’葡萄胚珠及种子发育,高效诱导其无核,且无核率达99.8%。克隆鉴定了VvMIR160s前体基因序列(501 bp)及成熟体序列,且它们在不同物种间具有较高的保守性;基于vvi-miR160s序列,预测到靶基因VvARF18,利用RLM-RACE技术检测到vvi-miR160s对VvARF18的裂解位点在第10和第11位之间,裂解频度9/17,证明VvARF18是vvi-miR160s的真实靶基因。该靶基因编码683个氨基酸,在398—411位存在核定位信号,且该蛋白亚细胞定位于细胞核上。VvARF18与其他物种间序列的同源保守性较高,基因结构相似,其中VvARF18蛋白与茶、烟草、梅花等物种亲缘关系较近。VvARF18启动子中包含4种作用元件,且含有较多激素相关元件。RT-qPCR结果显示,随着葡萄果实的发育,vvi-miR160c/d/e呈现‘V’形表达趋势,在硬核种子发育期表达较低,而VvARF18表现出与前者相反的表达趋势,在硬核种子发育期呈现高表达,表明vvi-miR160c/d/e对VvARF18负调控,但vvi-miR160a/b与VvARF18表达水平却不存在明显负相关。GA处理极显著地上调了vvi-miR160a/b在葡萄硬核种子发育期的表达,同时也显著抑制了VvARF18在同时期的表达,且它们的表达水平呈负相关,表明GA处理促进了vvi-miR160a/b对VvARF18的负调控作用;相反,GA减弱了vvi-miR160c/d/e对VvARF18的负调控作用。【结论】在vvi-miR160家族中,vvi-miR160c/d/e可能介导VvARF18在葡萄种子发育的特定阶段调控种子的发育形成,而vvi-miR160a/b可能主要介导VvARF18参与调控GA诱导葡萄种子败育的过程。 相似文献
3.
A. Di Francesco I. Cameldi F. Neri L. Barbanti A. Folchi A. Spadoni E. Baraldi 《Plant pathology》2019,68(8):1525-1532
Bull’s eye rot is a typical quiescent postharvest apple disease in major fruit-growing areas. The susceptibility of different apple cultivars to Neofabraea spp. (N. vagabunda and N. malicorticis) was assessed, with Granny Smith showing the most resistance and Cripps Pink the most susceptibility. To assess the factors involved in conidial germination, Neofabraea spp. were grown on crude protein extracts (CPEs) collected from apple fruits at different storage periods. Fungal germ tube growth rate and pathogenic enzyme (cellulase and xylanase) activity were assessed. Results showed that CPEs collected after 2 and 4 months of storage progressively stimulated conidial germination and germ tube elongation, while a lesser effect was observed from CPEs after 1 month of storage. Xylanase proved to be the main degrading enzyme secreted by all the isolates, while cellulase was produced only by N. vagabunda isolates. Overall, the isolate ID02 was the most virulent, based on more rapid germ tube elongation and greater activity of the lytic enzymes. 相似文献
4.
为了促进产业融合、实现加工增值、加快技术研发、达成跨季销售、推动冷链发展、增加劳动就业,对荠菜产业化相关研究进行总结。在此,有必要对荠菜的价值、研究意义及研究现状进行介绍,发现荠菜是一种具有较高营养价值和药用价值的野生叶菜,深受消费者青睐,市场前景广阔,具有重要的研究意义;另外,涉及荠菜的研究很多,但主要集中在栽培方面,品种与加工涉猎较少,特别是产业化更是鲜有涉足。通过对荠菜产业关键技术与装备的进一步研发,助力实现产业链的延伸,加快新品种、新技术、新模式、新工艺、新装备的应用。 相似文献
5.
本试验旨在研究奶牛采食前后瘤胃中短链脂肪酸(SCFA)浓度的变化及其吸收相关蛋白表达量的差异。试验选用3头体重(720±30)kg且装有瘘管的健康荷斯坦牛(动物伦理审查编号为SXAU-EAW-2019-C002013),采食精粗比为40:60的日粮(10kg),试验预试期10d,于第11天饲喂前开始取样,采用气相色谱法检测奶牛采食前(0 h)和采食后(1、2、3、4、5、6、7、8 h)瘤胃液中SCFA浓度;并采用荧光定量PCR方法检测瘤胃上皮组织中与SCFA吸收相关的蛋白表达量。结果表明:在采食后1 h奶牛瘤胃中SCFA浓度最高(P<0.05);在采食后一段时间内(2~5h)与SCFA吸收相关蛋白表达量上调(P<0.05),AE2、MCT1基因表达量均在5 h最高,PAT1、NHE3基因表达量均在4 h最高,MCT4基因表达量在4、5、6h均较高,NHE1基因表达量在2h达到最高;AE2、MCT1、MCT4、NHE1基因表达量与SCFA浓度负相关或正相关(P<0.05),AE2、MCT1、MCT4基因表达量与瘤胃内pH正相关(P<0.05)。以上结果初步揭示,在采食后一定时间内,瘤胃中与SCFA吸收相关蛋白表达受SCFA浓度和pH的调节。 相似文献
6.
The breadmaking quality of wheat is affected by the composition of gluten proteins and the polymerisation of subunits that are synthesised and accumulated in developing wheat grain. The biological mechanisms and time course of these events during grain development are documented, but not widely confirmed. Therefore, the aim of this study was to monitor the accumulation of gluten protein subunits and the size distribution of protein aggregates during grain development. The effect of desiccation on the polymerisation of gluten proteins and the functional properties of gluten were also studied. The results showed that the size of glutenin polymers remained consistently low until yellow ripeness (YR), while it increased during grain desiccation after YR. Hence, this polymerisation process was presumed to be initiated by desiccation. A similar polymerisation event was also observed when premature grains were dried artificially. The composition of gluten proteins, the ratios of glutenin to gliadin and high molecular weight-glutenin subunits to low molecular weight-glutenin subunits, in premature grain after artificial desiccation showed close association with the size of glutenin polymers in artificially dried grain. Functional properties of gluten in these samples were also associated with polymer size after artificial desiccation. 相似文献
7.
8.
The saddle panels, directly in contact with the horse's back, are likely an important element to optimize the fitting of the saddle, the comfort of the horse, and subsequently, the pain management in dorsalgic horses. The aim of this study was to better understand the effect of the saddle panels on the horse's back, by evaluating a prototype saddle (comfort panels: CP) compared to a standard saddle (STD). The horse's back movements were measured using inertial measurement units (IMUs) fixed at the levels of thoracic vertebrae T6, T12, T16 (under the saddle) and lumbar vertebrae L2 and L5. The centers of mass (COMs) of the horse and the rider and limb's protraction-retraction angles, pressure between saddle and horse's back, and force on the stirrups were measured using respectively 2D motion capture, pressure mat and force sensors in the stirrup leather. Three horses were trotted at the rising trot (sitting: left diagonal-rider seated; standing: right diagonal-rider standing) by the same rider. To compare saddles, linear mixed-effects regression models were used. The estimated means (SE) were calculated. During sitting phase, pressure in the cranial and middle areas of the saddle significantly increased for CP compared to STD (+0.9 (0.2) kPa and +1.0 (0.1) kPa, respectively) whereas caudal pressure decreased (−1.8 (0.4) kPa). Concurrently, the range of motion of angles T12-T16 and T16-L2 under the saddle significantly increased (+1.8 (0.2)° and +2.3 (0.3)°, respectively). The results showed that modifications of the panels' shape not only affect the pressure distribution but also the kinematics of the thoracic and lumbar regions of the equine back. 相似文献
9.
10.