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81.
应用Eberhart的性状值回归参数b_i及S_(di)~2、Tai的结构模型参数和,Ecovalence(W)值等参数,对泡桐品种多点试验林8个无性系生长量的基因型稳定性和生长适应性进行了分析。并结合生产力对各无性系进行了综合评定。结果表明:选出的8112-3和8112-1属速生、稳定、适应性强的无性系;8112-4和7606-6属于速生但不稳定的无性系,只适宜于较好的环境条件。经聚类分析将采用的8个参数明显地归为三类,类间相互独立,可分别用于评价基因型的生产力、遗传稳定性和适应性。 相似文献
82.
泡桐无性系苗期叶部性状的主成分分析 总被引:2,自引:0,他引:2
经对15个泡桐无性系苗期叶部性状的主成分分析表明:叶大小和叶形状是泡桐无性系苗期叶部性状差异的主要因素,作为主成分可代表叶部信息量的87%。因而在苗期选择时可作为主要参考因子。 相似文献
83.
The effects of ethylene and CO2 on shoot regeneration in excised leaf cultures of Paulownia kawakamii were examined. When both the gases were prevented from accumulating in the headspace of cultures using mercuric perchlorate and potassium hydroxide traps, shoot regeneration frequency improved and callus production was reduced compared to the control and cultures with only one of the gases trapped. Incorporation of either aminoethoxyvinylglycine (AVG) or 1-amino-cyclopropane-1-carboxylic acid (ACC) in the culture medium caused significant reduction in shoot regeneration. There was profuse callus production in the presence of high amounts of ACC, which was accompanied by over sixfold increase in the rate of ethylene production. However, in the presence of AVG callus production was delayed and shoot regeneration decreased, suggesting that low levels of ethylene might be needed for de novo shoot bud induction in Paulownia cultures.Abbreviations IAA
Indole-3-acetic acid
- MP
mercuric perchlorate
- AVG
aminoethoxyvinylglycine
- ACC
1-aminocyclopropane-1-carboxylic acid 相似文献
84.
E. T. NILSEN 《Plant, cell & environment》1992,15(4):455-461
Stem and leaf photosynthetic responses to environmental parameters were studied in Spartium junceum L., a legume with chlorophyllous stems. Stem net photosynthesis (Pn) was consistently lower than leaf Pn. The low stem Pn was due to lower quantum yield, lower mesophyll conductance and lower CO2-saturated Pn than that of leaf Pn. Stomatal limitations to leaf and stem Pn were similar (25%). Water stress caused a greater reduction in leaf Pn than that of stems. Leaf Pn was also reduced in water-stressed plants following rehydration. The reduced leaf Pn was associated with a reduced photon saturated Pn rate and a reduced CO2 saturated Pn rate. Apparent quantum yield, mesophyll conductance and stomatal limitation of leaves were unaffected by water-stress. Stem Pn following rehydration was not influenced by the water-stress treatment. In general, leaf Pn was more responsive to environmental parameters and more sensitive to water stress than stem Pn. These data support the hypothesis that stem Pn has greater tolerance of water stress, but is limited to low Pn by biochemical means compared to leaves. 相似文献
85.
Paulownia taiwaniana, the widely cultivated, commercially important tree, has been suspected of being of hybrid origin at least since its original publication in 1975. Evidence in support of this thesis, derived from a number of different investigations, is presented in this paper.—Strong evidence comes from a controlled pollination study of the two supposed parental species,P. kawakamii andP. fortunei. F1 seedlings, derived from reciprocal crosses between the suspected parents, exhibited identical banding patterns for a number of enzymes (such as SKDH, GOT, and IDH) withP. taiwaniana, when separated by electrophoresis. Furthermore, comparative morphological studies of trichomes and wood parenchyma patterns between the purported parents andP. taiwaniana reveal that this latter qualitatively exhibits characteristics that combine features of both of the suspected parental types. Biochemically, eight enzyme systems were compared in the three species here under discussion, and, without exception, the electrophoretic banding patterns exhibited byP. taiwaniana represented a combination of the alleles of the other two species. Perhaps the most convincing evidence comes from a genetic analysis of the progeny obtained by selfingP. taiwaniana. Genotypic segregation of the offspring based on a single locus each of SKDH and PGI fit the 1:2:1 hypothesis. Genotypic segregation of the offspring based on two loci each of SP and GOT fit the ratio of 3:6:3:1:2:1. This, taken in conjunction with the other data presented, clearly suggests thatP. taiwaniana is a hybrid involvingP. kawakamii andP. fortunei. 相似文献
86.
为寻找新的能产生抗生素的植物内生真菌,采用3种培养基对毛泡桐进行内生真菌的分离,以大肠埃希菌、枯草芽胞杆菌、金黄色葡萄球菌、青枯假单胞菌为指示菌,利用琼脂块法和滤纸片扩散法筛选能抑制细菌的菌株;通过形态特征和ITS序列分析鉴定高活性菌株。结果从毛泡桐的根、茎、叶中共分离得到46株内生真菌,至少能抑制一种指示菌的有9株,其中菌株KLBMP-Pt630、KLBMP-Pt675和KLBMP-Pt686活性较强,鉴定结果显示:KLBMP-Pt630为三线镰刀菌、KLBMP-Pt675为棒曲霉、KLBMP-Pt686属于肉座菌目真菌。 相似文献
87.
Bryan A. Bailey Harry C. Evans Wilbert Phillips‐Mora Shahin S. Ali Lyndel W. Meinhardt 《Molecular Plant Pathology》2018,19(7):1580-1594
Taxonomy : Moniliophthora roreri (Cif.) H.C. Evans et al. 1978 ; Phylum Basidiomycota; Class Agaricomycetes; Order Agaricales; Family Marasmiaceae; Genus Moniliophthora. Biology : Moniliophthora roreri attacks Theobroma and Herrania species causing frosty pod rot. Theobroma cacao (cacao) is the host of major economic concern. Moniliophthora roreri is a hemibiotroph with a long biotrophic phase (45–90 days). Spore masses, of apparent asexual origin, are produced on the pod surface after initiation of the necrotrophic phase. Spores are spread by wind, rain and human activity. Symptoms of the biotrophic phase can include necrotic flecks and, in some cases, pod malformation, but pods otherwise remain asymptomatic. Relationship to Moniliophthora perniciosa : Moniliophthora roreri and Moniliophthora perniciosa, causal agent of witches’ broom disease of cacao, are closely related. Their genomes are similar, including many of the genes they carry which are considered to be important in the disease process. Moniliophthora perniciosa, also a hemibiotroph, has a typical basidiomycete lifestyle and morphology, forming clamp connections and producing mushrooms. Basidiospores infect meristematic tissues including flower cushions, stem tips and pods. Moniliophthora roreri does not form clamp connections or mushrooms and infects pods only. Both pathogens are limited to the Western Hemisphere and are a threat to cacao production around the world. Agronomic importance : Disease losses caused by frosty pod rot can reach 90% and result in field abandonment. Moniliophthora roreri remains in the invasive phase in the Western Hemisphere, not having reached Brazil, some islands within the Caribbean and a few specific regions within otherwise invaded countries. Disease management : The disease can be managed by a combination of cultural (for example, maintenance of tree height and removal of infected pods) and chemical methods. These methods benefit from regional application, but can be cost prohibitive. Breeding for disease resistance offers the greatest potential for frosty pod rot management and new tolerant materials are becoming available. 相似文献
88.
Seeds of the empress tree ( Paulownia tomentosa Steud.) were imbibed for two weeks in darkness at constant temperatures (18, 23 or 28°C), and then irradiated with red light for 5 min. Germination was poor if it took place at the same temperature as imbibition, but a high percentage was achieved if the seeds were exposed to higher or lower temperatures before they were irradiated. Maximum germination was obtained when the difference between pretreatment and imbibition was about 10°C. The effect increased with the duration of the pretreatment and was optimal at 24 h. The effect decreased as the time lapse between temperature pretreatment and red light irradiation increased, and it was lost after two days. If pretreatment was shorter than 24 h (12 h). a high percent of germination was obtained by alternating pretreatment and imbibition temperatures. The germination of seeds imbibed in 40% heavy water was also stimulated by temperature pretreatments. Light and temperature also exhibited an interactive effect in the germination of seeds that were imbibed in darkness for only 3 days. For each of the germination phases there was a temperature at which the time needed for 50% germination was the shortest, namely 35°C during imbibition, 37.5°C in the period of Pfr activity. and 32.5°C during radicle protrusion. The data obtained are shortly discussed in relation to the domestication of empress tree in Southern Europe. 相似文献
89.
90.