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1.
Tissue-specific expression of two members of the cell wall hydroxyproline-rich glycoprotein (HRGP) family, extensin and potato tuber lectin, was examined by immunolocalization at the light microscope level in various organs (leaves, stems, roots, fruit, tuber) of carrot ( Daucus carota cv. Thumbelina), tomato ( Lycopersicon esclentum cv. Pixie Hybrid II), and potato ( Solanum tuberosum cv. Kennebec). Extensin was prominently expressed in vascular tissue, particularly xylem and also phloem, although virtually all cells displayed some degree of staining which varied as a function of the tissue, organ, and plant under study. Antibodies against potato tuber lectin (PTL) displayed a localization pattern similar to that observed for extensin; notably PTL did not stain cambium but did stain epithelial cells lining secretory cavities. These distribution patterns are consistent with a role for extensin, and possibly PTL, in providing mechanical support in tissues subjected to compression or torsional stress imparted by vascular growth, or by similar stress brought about by transport of vascular fluids. 相似文献
2.
Area‐wide monitoring of potato tuberworm (Phthorimaea operculella) by pheromone trapping in Northern Italy: phenology,spatial distribution and relationships between catches and tuber damage 下载免费PDF全文
Antonio Masetti Alda Butturini Alberto Lanzoni Valentino De Luigi Giovanni Burgio 《Agricultural and Forest Entomology》2015,17(2):138-145
- The potato tuberworm (PTW) Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is key pest of potato in tropical and subtropical regions. From 2002 onward, PTW has emerged as a problem in the Bologna province, the main potato production area in Northern Italy.
- Field investigations were performed to study the temporal and spatial dynamics of PTW. Adult moths were monitored using pheromone‐baited traps over 3 years (2009–2011). Traps were georeferenced and catches were analyzed by geostatistical maps. Each year, the percentage of damaged tubers at harvest was assessed.
- Pheromone trapping, integrated with temperature‐dependent developmental times, showed that PTW completed two generations throughout the potato‐growing season; the remaining generations developed in the noncrop season. Maps showed a clumped distribution of PTW at the landscape scale. The hot spots of infestation corresponded to the areas most intensively cropped with potato. Trap catches from hilling to harvesting were linearly and positively correlated with the percentage of damage in 2 out of 3 years and in the pooled data set.
- The present study demonstrated the widening of PTW areal to Northern Italy. In this area, georeferenced pheromone traps were validated as a useful monitoring technique for describing the phenology and distribution of PTW, thus providing crucial knowledge for the rational management of this pest.
3.
甘薯分子遗传图谱的建立对甘薯分子育种技术体系的拓展和应用具有重要意义。当前,对甘薯分子遗传图谱的研究虽然取得一定的进展,但存在着很多技术瓶颈,如作图策略应用和优化等。总结了甘薯经典和分子遗传研究进展,剖析了甘薯分子遗传图谱作图的3种方法与策略;探讨和提出了提高甘薯作图效率和质量的途径主要是:优化作图群体质量、克服偏分离、整合多群体间遗传连锁图谱和选择合适的分子标记类型;并指出染色体关联在遗传作图中的重要性,提出甘薯分子育种领域亟待加强的方面,以期为今后甘薯精密分子图谱的建立及基于分子图谱的甘薯分子育种提供新的思路。 相似文献
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5.
研究了不同菌株组合,马铃薯植株茎、叶及接种物中A1和A2菌株孢子囊比例、温度、湿度对卵孢子产生的影响。不同菌株组合产生卵孢子的数量有显著差异;在离体接种情况下,叶片中产生卵孢子数量大于茎中产生卵孢子数量;A1和A2菌株中孢子囊不同比例对卵孢子产生影响很大,当比值为1∶1时卵孢子产生量最大;15℃光照条件下培养,并给侵染叶片持续的水分供应才能产生大量卵孢子;寄主的抗性水平对卵孢子产生有明显的影响,中抗品种上产生卵孢子量最多,高抗品种上产生卵孢子量最少,感病品种上产生卵孢子量居中。 相似文献
6.
H_2O_2和水杨酸对陈化马铃薯切片交替呼吸途径影响的比较(英文) 总被引:1,自引:0,他引:1
外源 5 .0mmol/LH2 O2 和 0 .1mmol/L水杨酸 (salicylicacid ,SA)处理均可明显提高陈化 2 4h的马铃薯切片的交替呼吸途径容量 (Valt)及其与总呼吸的比值 (Valt/Vt)。应用交替氧化酶的单克隆抗体进行Western杂交的结果表明 ,H2 O2 和SA处理均可明显提高陈化马铃薯切片中交替氧化酶的表达水平。用氧同位素分辨法研究 ,结果表明 :H2 O2 处理对陈化马铃薯切片中交替呼吸途径的实际运行没有影响 ,而SA处理对交替呼吸途径的实际运行具有明显的促进作用。上述结果表明 ,H2 O2 和SA对植物组织交替呼吸途径的影响存在差异 ,二者均可促进交替氧化酶的表达从而诱导交替呼吸途径容量的发生 ,但H2 O2 不影响其实际运行 ,而SA还可同时诱导其实际运行。 相似文献
7.
Athanasios Dalakouras Elena Dadami Michele Zwiebel Gabi Krczal Michael Wassenegger 《Epigenetics》2012,7(9):1071-1078
In plants, RNA-directed DNA methylation (RdDM) can target both transgene promoters and coding regions/gene bodies. RdDM leads to methylation of cytosines in all sequence contexts: CG, CHG and CHH. Upon segregation of the RdDM trigger, at least CG methylation can be maintained at promoter regions in the progeny. So far, it is not clear whether coding region methylation can be also maintained. We showed that the body of Potato spindle tuber viroid (PSTVd) transgene constructs became densely de novo methylated at CG, CHG and CHH sites upon PSTVd infection. In this study, we demonstrate that in viroid-free progeny plants, asymmetric CHH and CHG methylation was completely lost. However, symmetric CG methylation was stably maintained for at least two generations. Importantly, the presence of transgene body methylation did not lead to an increase of dimethylation of histone H3 lysine 9 or a decrease of acetylation of H3. Our data supports the view that CG methylation can be maintained not only in promoters but also in the body of transgenes. They further suggest that maintenance of methylation may occur independently of tested chromatin modifications. 相似文献
8.
高必需氨基酸转基因马铃薯的研究 总被引:8,自引:0,他引:8
80年代以来,马铃薯遗传转化系统日趋成熟,转基因工程植株已被广泛应用于基础科学研究[1]。作为食物蛋白和能量主要来源的马铃薯,提高其蛋白质含量及质量的遗传工程研究正受到人们的普遍关注[2]。Yang等[2]将旨在改善氨基酸平衡的CAT-HEAAE(氯酶素乙酰转移酶-高含量人体必需氨基酸)融合基因导入马铃薯,获得了Southernblot、Northernblot、Westernblot的证据,但尚缺少氨基酸分析的资料。玉米醇溶蛋白(zein)[3]是一个富含甲硫氨酸的贮存蛋白,它和人工合成的HE… 相似文献
9.
甘肃省中部沿黄灌区轮作和连作马铃薯根际土壤真菌群落的结构性差异评估 总被引:11,自引:0,他引:11
甘肃省中部沿黄灌区是西北地区乃至全国重要的加工型马铃薯生产基地,然而因集约化种植带来的连作障碍问题已经严重影响到当地马铃薯种植业的可持续发展。采用大田试验与PCR-DGGE(Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis)技术相结合的方法,并通过真菌的18S r DNA序列分析,评估轮作(未连作)和连作条件下马铃薯根际土壤真菌群落在组成结构上的差异,以期为甘肃省中部沿黄灌区马铃薯连作的土壤障碍机理研究提供新证据。结果表明,同轮作相比,连作显著降低了马铃薯块茎产量和植株生物量,并且随着连作年限的延长,连作障碍也愈加严重。长期连作(6a)也导致马铃薯根冠比显著增加和植株收获指数的显著下降。在根际土壤真菌的种群数量和多样性上,连作和轮作间无显著差异,但在群落组成结构上差异明显。真菌18S r DNA测序分析进一步表明,马铃薯连作较轮作相比增加了Fusarium sp.和Fusarium solani以及Verticillium dahliae的种群或个体数量,而这些真菌是导致马铃薯土传病害的主要致病菌类型。根际土壤真菌群落组成结构的改变特别是与土传病害有关的致病菌滋生可能是导致当地马铃薯连作障碍的重要原因。 相似文献
10.
The effects of different seed sizes, planting densities and planting patterns on the transmission of silver scurf (Helminthosporium solani) and black scurf (Rhizoctonia solani) diseases of potatoes were examined in five field experiments with cv. Estima in 1991–93.
In all experiments, silver scurf was more severe with increase in seed size and planting density. At high planting density, silver scurf was less severe from a square planting pattern than from planting in wide rows. The incidence of black scurf also tended to increase with increase in seed size and was increased markedly high planting density. 相似文献
In all experiments, silver scurf was more severe with increase in seed size and planting density. At high planting density, silver scurf was less severe from a square planting pattern than from planting in wide rows. The incidence of black scurf also tended to increase with increase in seed size and was increased markedly high planting density. 相似文献