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Wild olive (Olea europaea subsp. europaea var. sylvestris) is an important component of Mediterranean forests and a key genetic source for olive improvement programmes. Since 2009, a severe decline caused by Phytophthora cryptogea and P. megasperma has been detected in a protected wild olive forest of high ecological value (Dehesa de Abajo, Seville, Spain). In this natural forest, sampling of roots and soil was carried out on 25 wild olives with symptoms in 2014 and 2015. Apart from the already known P. cryptogea A1 and P. megasperma, a third Phytophthora species was consistently isolated from wild olive rootlets with symptoms. These isolates conformed morphologically with the newly described species P. oleae and were confirmed by analysis of their ITS regions and cox1 sequences. Temperature–growth relationships showed a maximum growth at 19.9 °C on carrot agar medium, making it the lowest temperature Phytophthora species infecting wild olive roots. Pathogenicity was confirmed on 1-year-old healthy wild olive seedlings and was similar to the previously known pathogenic phytophthoras. As temperature requirements are quite different, the three Phytophthora species may be active against wild olive roots in different seasons. However, the prevalence of P. oleae infecting wild olives in recent years could be due to its introduction as a new invasive pathogen. The probable invasive nature of P. oleae, together with increasing rain episodes concentrated in short periods frequent in southern Spain, would allow the outbreak of infections in wild olive forests, and also put cultivated olive orchards at risk. 相似文献
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不同覆盖方式对云南干热河谷油橄榄园土壤温度、水分和容重的影响 总被引:2,自引:0,他引:2
对云南省金沙江干热河谷永仁地区油橄榄园地进行覆盖试验,研究了不同材料覆盖后油橄榄园土壤温度、水分、容重变化。结果表明,覆盖对土温变化的调节作用主要表现在土壤表层,随土层深度增加调节作用减小;夏季油橄榄园覆盖后随气候温度升高土壤温度日变幅减小;不同材料覆盖间存在差异,薄膜覆盖土温变幅最大,纸箱次之,秸秆变幅最小。覆盖提高了园地土壤含水量,有较好的保墒效果;覆盖秸秆、杂草0~20cm土层含水量较高;随着土壤深度增加,不同覆盖处理之间土壤水分含量差异增大。4种材料覆盖均有利于降低土壤容重,其中以秸秆效果最显著。 相似文献
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【目的】建立并确定盐生植物盐角草(Salicornia europaea L)同化枝不定芽诱导与增殖的试验体系和培养基。【方法】以MS为基本培养基,通过附加不同浓度激素(TDZ、NAA、6-BA)及盐(NaCl)进行盐角草不定芽的诱导,筛选诱导盐角草不定芽的最适激素配比及盐浓度;后期通过对细胞分裂素TDZ浓度(0、1.6、1.8、2.0和2.5 mg/L)的摸索,确定盐穗木不定芽增殖的最适浓度。【结果】盐角草同化枝在含有200 mM NaCl的MS3(2.0 mg/L TDZ、0.1 mg/L NAA)培养基中不定芽诱导率达32.4%,显著高于(P<0.05)其余组,为最适诱芽培养基。再生的不定芽在含有2.0 mg/LTDZ的培养基中经过30~40 d的培养,不定芽增殖率可达619.5%。盐角草不定芽诱导及增殖最适培养基均为:MS+2.0 mg/L TDZ+0.1 mg/L NAA+200 mM NaCl。【结论】一定浓度的TDZ、NAA及NaCl组合,可通过直接器官发生途径有效诱导盐角草同化枝不定芽的产生和增殖。 相似文献
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S. Goldental-Cohen I. Biton Y. Many K. Tavrizov A.M. Dourou H. Zemach 《The Journal of Horticultural Science and Biotechnology》2019,94(4):488-498
A typical olive (Olea europaea L.) inflorescence consists of about 20 flowers. However, in many cultivars, only one fruit develops. This is due to massive abscission of flowers and fruitlets, which occurs during the first month after anthesis. In this study, we used the olive cultivar 'Barnea' to characterize the abscission mechanism and to try to increase fruit set by increasing the number of developed fruit per inflorescence. Removing the lateral flowers 3 weeks before anthesis increased fruit set by more than 50%. Removing all inflorescences but one from a branch increased the number of developed fruits from 0.93 to 2.8 during 2017 and from 0.91 to 3.34 fruits per inflorescence in 2018. Sugar quantification in the pistil revealed that starch level is high on the day of anthesis and low 25 days later in abscised as well as in developed fruit. Soluble carbohydrates are low on the day of anthesis, low in abscised flowers/fruitlets 25 days after anthesis and high in developed fruit. Screening the natural variation found in the Israeli germplasm collection revealed that in most cultivars less than one fruit per inflorescence has developed. However, there are unique cultivars with a higher fruit set. 相似文献
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Protection of olive planting stocks against parasitism of root-knot nematodes by arbuscular mycorrhizal fungi 总被引:3,自引:0,他引:3
P. Castillo A. I. Nico C. Azcón-Aguilar C. Del Río Rincón C. Calvet R. M. Jiménez-Díaz 《Plant pathology》2006,55(5):705-713
The effects were investigated, under controlled conditions, of single and joint inoculation of olive planting stocks cvs Arbequina and Picual with the arbuscular mycorrhizal fungi (AMF) Glomus intraradices , Glomus mosseae or Glomus viscosum , and the root-knot nematodes Meloidogyne incognita and Meloidogyne javanica , on plant performance and nematode infection. Establishment of the fungal symbiosis significantly increased growth of olive plants by 88·9% within a range of 11·9–214·0%, irrespective of olive cultivar, plant age and infection by M. incognita or M. javanica . In plants free from AMF, infection by Meloidogyne spp. significantly reduced the plant main stem diameter by 22·8–38·6%, irrespective of cultivar and plant age. Establishment of AMF in olive plants significantly reduced severity of root galling by 6·3–36·8% as well as reproduction of both Meloidogyne spp. by 11·8–35·7%, indicating a protective effect against parasitism by root-knot nematodes. Infection by the nematodes influenced root colonization by AMF, but the net effect depended on the AMF isolate–olive cultivar combination. It is concluded that prior inoculation of olive plants with AMF may contribute to improving the health status and vigour of cvs Arbequina and Picual planting stocks during nursery propagation. 相似文献
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为研究油橄榄在酸性土壤、夏雨型气候环境下的生长发育特征,因地制宜开展田间栽培管理提供科学依据。以中国南方3个油橄榄适生良种豆果、柯基和尼Ⅰ为材料,比较花芽分化、花期物候、花序特征、单果重和含油率差异。结果显示:3个品种的花芽分化均起始于3月上旬,豆果和尼Ⅰ初花期为5月3日,花期分别为10、6 d;柯基初花期为5月4日,花期11 d。豆果、尼Ⅰ、柯基的平均花序长度分别为2.5、2.5、2.9 cm,单个花序平均小花数量分别为16.3、14.9、17.9个。果实转色的先后次序和成熟期的早晚一致,依次为尼Ⅰ、豆果和柯基;单果重和含油率随着时间的推移均呈上升趋势,但二者增速不同,单果重在果实发育前期增长较快,含油率在果实发育后期增长较快。至10月24日果实成熟度分别达M5(尼Ⅰ和豆果)和M4(柯基),尼Ⅰ的单果重和含油率分别为3.40 g、13.05%,豆果的单果重和含油率分别为1.15 g、14.31%,柯基的单果重和含油率分别为0.77 g、12.31%。综上表明,3个品种花期基本一致,柯基的花量大、花期长,可作为授粉品种加以利用;在果实的生长发育过程中,前期应加强田间肥水管理,以确保树体处于良好的营养水平,为后期油分积累奠定物质基础,同时在梅雨季节要注意及时排水。 相似文献
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为比较不同品种油橄榄叶果之间多酚含量的差异,以云南引种的16个品种油橄榄叶样及13个品种的果渣样为原料,采用4因素3水平正交试验设计,选出微波辅助提取油橄榄多酚物质最优水平组合为:萃取功率为600 W、萃取时间为20 min、萃取温度为120℃、乙醇-水溶液浓度为40%,以此为微波萃取工艺条件,提取油橄榄叶样及果渣样中多酚物质,并测其含量。结果表明,叶样多酚含量鄂植8号中的最低,为1.02%,城固53中最高,为8.29%;果渣样品中多酚含量,阿斯最低,为0.64%,而莱星最高,为1.56%,油橄榄叶样中多酚含量平均值(4.21%)大于果渣中多酚平均含量(1.10%)。实验结果为从油橄榄中获取天然抗氧化剂,以延伸油橄榄产业链提供理论依据。 相似文献
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Intraspecific olive diversity assessed with AFLP 总被引:6,自引:0,他引:6
F. Sanz-Cortés D. E. Parfitt C. Romero D. Struss G. Llacer M. L. Badenes 《Plant Breeding》2003,122(2):173-177
Amplified fragment length polymorphism (AFLP) was used to study diversity within and among Spanish olive varieties. A high degree of diversity was found among the varieties present in each growing region. Olive oil production and quality relies on appropriate cultivar selection as well as good orchard management. Production based only on a few superior cultivars would result in improved yield, oil quality, and production management. Amplified fragment length polymorphism were evaluated as a tool to identify the intraspecific and intravarietal diversity of olive. Amplified fragment length polymorphism analysis of 38 accessions belonging to 10 cultivars using six primer combinations produced 106 polymorphic bands. Results were analyzed for similarity among accessions via unweighted pair‐group means cluster analysis, resulting in 10 clusters corresponding to named variety designations. Similarity among varieties ranged from 0.60 to 0.72. Diversity within varieties was identified. Similarity within named varieties (accessions with the same varietal name) ranged from 0.75 to 0.96. Differences in several markers were found among 34 accessions. Intravarietal diversity was shown to exist within the Spanish olive varieties grown in the region surrounding Valencia. 相似文献