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81.
82.
利用胚性细胞悬浮系研究香蕉枯萎病抗性离体筛选技术 总被引:3,自引:0,他引:3
以香蕉(Musa spp. AAA group)胚性细胞悬浮系(Embryogenic Cell Suspension,ECS)为试材,进行抗枯萎病离体筛选技术研究。首先测试不同的γ射线(60Co)辐射剂量对ECS植株再生能力的影响;在此基础上,以不同浓度的枯萎病病原菌毒素粗滤液(FOC)为选择压力,研究FOC对ECS植株再生能力的影响,并进行离体抗性筛选。结果表明,ECS的植株再生能力与辐射剂量之间呈负相关,半致死剂量为70~80Gy。同样地,未经辐射处理的ECS其植株再生能力也随着FOC体积分数的增加而急剧下降,但经辐射处理过的ECS其植株再生能力与CK相比成倍地增加;当FOC体积分数达到12%后,只有从经80Gy辐射后的ECS获得了再生植株。这表明ECS耐FOC的能力随着辐射剂量的增加而增强。 相似文献
83.
Are rhododendron hybrids distinguishable on the basis of morphology and microsatellite polymorphism?
Sequence Tagged Microsatellite Sites (STMSs) and morphological trait markers were used to evaluate 33 rhododendron germplasm for genetic diversity assessment and discrimination power. The average genetic diversity estimates were 0.724 (morphological traits) and 0.174 (STMSs) marker datasets. The Shannon index was higher for morphological traits (1.797) than STMS (0.302). The correlation coefficients obtained by the Mantel matrix correspondence test, which was used to compare the cophenetic matrices for the two markers, showed that estimated values of relationships given for morphological and STMS were not significantly related (p > 0.05). The dataset from STMS, supported by the total probability of identity (1.13 × 10−9) and total paternity exclusion probability (0.9999), allowed all accessions to be uniquely identified. In summary, STMS marker proved to be an efficient tool in assessing the genetic variability among old broad leaf rhododendron genotypes. The pattern of variation appeared to be consistent, and it can be used for germplasm conservation and management for restoration of historical genetic resources. 相似文献
84.
桉树栽培紫芝及营养成分分析 总被引:2,自引:0,他引:2
为探讨桉树栽培紫芝的可行性,笔者于2012年-2013年利用当地5年~6年树龄的尾叶桉为菌材,开展了桉树栽培紫芝对比试验,并对其灵芝产品营养成分送样检测。结果表明,利用桉树栽培紫芝是可行的,其菌丝生长速度快于米槠(CK)菌材,当年平均产量(早晚季合计)25.42kg·m^-3,比对照提高2.67%,差异不显著;氨基酸、粗多糖等营养成分经福建省分析测试中心检测,桉树早季灵芝总氨基酸含量(TAA)6.05g/100g,晚季灵芝总氨基酸含量(TAA)7.31g/100g,早季粗多糖含量0.52g/100g,晚季粗多糖含量0.67g/100g,比米槠(CK)栽培粗多糖含量0.59g/100g高13.56‰ 相似文献
85.
86.
Iñigo Loureiro María Concepción Escorial María Cristina Chueca 《Pest management science》2023,79(6):2247-2254
BACKGROUND
Cultivated bread wheat (Triticum aestivum L.) spontaneously hybridizes with wild/weedy related Aegilops populations, but little is known about the actual rates at which this hybridization occurs under field conditions. It is very important to provide reliable empirical data on this phenomenon in order to assess the potential crop–wild introgression, especially in the context of conducting risk assessments for the commercialization of genetically modified (GM) wheat, as gene flow from wheat to Aegilops species could transfer into the wild species genes coding for traits such as resistance to herbicides, insects, diseases or environmental stresses.RESULTS
The spontaneous hybridization rates between wheat and A. geniculata and A. triuncialis, which are very abundant in the Mediterranean area, have been estimated for the first time in the northern part of the Meseta Central, the great central plateau which includes the largest area of wheat cultivation in Spain. Hybridization rates averaged 0.12% and 0.008% for A. geniculata and A. triuncialis, respectively. Hybrids were found in 26% of A. geniculata and 5% of A. triuncialis populations, at rates that can be ≤3.6% for A. geniculata and 0.24% for A. triuncialis.CONCLUSION
The detection of Aegilops spp.–wheat hybrids in Aegilops populations indicates that gene flow can occur, although wheat is considered a crop with a low-to-medium risk for transgene escape. These data on field hybridization rates are essential for GM wheat risk assessment purposes. © 2023 Society of Chemical Industry. 相似文献87.
P. Nicholson A.S. Turner S.G. Edwards G.L. Bateman L.W. Morgan D.W. Parry J. Marshall M. Nuttall 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(2):163-177
The progress of development of stem-base pathogens in crops of second winter wheat was plotted in nine experiments in three years. The amount of each pathogen present was determined by quantitative PCR. Where Tapesia yallundae was present in quantifiable amounts, it usually developed earlier than the other eyespot pathogen, T. acuformis. Both species were usually present in greater amounts on cultivars which are more susceptible to eyespot. The sharp eyespot pathogen, Rhizoctonia cerealis, developed more erratically than either of the Tapesia spp. and there were no consistent effects on different cultivars. Fusarium spp., the cause of brown foot rot, were rarely present in quantifiable amounts, but Microdochium nivale was usually present as one or both of the varieties nivale and majus. Late-season (after anthesis) decreases in M. nivale suggest that any brown foot rot symptoms attributable to this fungus would have fully developed earlier. Cultivar differences in amounts of M. nivale were most clear in stems during internode extension and when relatively large amounts of DNA were present. Such differences approximately reflected eyespot susceptibility, cv. Soissons containing most and cv. Lynx containing least DNA. The results emphasise the difficulty in relating diagnoses, by quantitative PCR or other means, at early growth stages when decisions to apply fungicides against stem-base disease are made, to later disease severity. 相似文献
88.
测定了致病杆菌CB43菌株代谢物对灰葡萄病菌菌丝生长和孢子萌发的影响。结果表明:CB43代谢物对灰葡萄孢菌丝生长有较强的抑制作用,500、250、125ml/L代谢物能完全抑制菌丝的生长,并具有杀死作用。62.5ml/L的发酵液处理灰葡萄病菌菌丝72h的抑制率仍达83.35%。20ml/L的发酵液处理灰葡萄孢菌丝能引起菌丝畸形,异常分支、粗短。CB43代谢物能杀死灰葡萄孢分生孢子或抑制其萌发,500~62.5ml/L的发酵液处理16h后,孢子萌发抑制率达88.1%~97.91%。温室试验表明,CB43代谢物对黄瓜灰霉病的控制效果达84.09%,化学农药40%施佳乐的效果为72.94%。 相似文献
89.
测定了6个Bacillus spp.和1个Pseudomonas sp.P-13(G-对照菌株)在PPM培养基上的相互作用。在总共42个组合中,有27个组合是可亲和性的。在以B5423为单剂之一的5个组合中,亲和性的组合有4个。在温室条件下通过分批播种,在水稻分蘖盛期喷以B5423-R(B5423的标记菌株,是利福平抗性的突变体)为单剂之一的4个亲和性组合的菌悬浮液,以检测该组合中B5423-R在水稻茎基部的种群数量。结果发现,与单剂B5423-R相比,在应用1~7天内,组合B5423-R B45中,B5423-R的群体数量显著性降低;组合B5423-R B95、B5423-R B77中,B5423-R的群体数量与单剂无显著差异;组合B5423-R B4313中,B5423-R的群体数量在应用1~4天内与单剂无显著性差异,但在应用第7天显著地高于单剂。离体叶片纹枯病痛斑面积的抑制试验表明,与各自的单剂相比,组合B95 B5423及B95 Er77显著地抑制了纹枯病病斑面积;而组合B45 B80、B45 B5423和B45 B95纹枯病病斑面积显著地高于各自的单剂;其余10个组合与各自的单剂无显著差异。 相似文献
90.
Suppression of wheat-seedling diseases caused by Fusarium culmorum and Microdochium nivale using bacterial seed treatment 总被引:1,自引:0,他引:1
Snow mould, caused by Microdochium nivale , and seedling blight caused by members of the Fusarium complex, are cereal diseases of great economic importance in many temperate zones. In a glasshouse bioassay designed to enhance disease, about 600 plant-associated bacterial isolates obtained by different methods were screened for suppressive effects in wheat against infection caused by Fusarium culmorum . Although most of the isolates tested had a neutral effect on test plants and disease development, a few were synergistic to the pathogen and about one-fifth showed > 80% disease suppression. During five consecutive growing seasons, 164 bacterial isolates were tested in field experiments against both F. culmorum and M. nivale as causal agents of seedling blight. Tests for effects on yield in experiments with spring and winter wheat, performed in different climatic regions of Sweden, showed that disease-suppressive effects were repeatable. The most efficient isolates, three fluorescent pseudomonads and a species of Pantoea , suppressed disease equal to that of the fungicide guazatine, both with respect to crop stand and yield. Seed treatment with Pantoea sp. (isolate MF 626) increased yield by an average of more than 500 kg ha−1 in six field experiments. 相似文献