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101.
Z. H. Sierota 《Forest Pathology》1977,7(3):164-172
The mycelial yield of Trichoderma viride on a number of carbon sources and the inhibitory effect of its filtrates on Fomes annosus were investigated. d-Xylose and d-glucose as carbon sources in the media gave the highest degree of inhibition when their filtrates were directly tested against F. annosus mycelium. The protection of pine wood blocks with filtrates was most effective when these were derived from cellulose and d-xylose. 相似文献
102.
A quantitative trait loci (QTL) associated with resistance to pea rust, caused by the fungus Uromyces pisi (Pers.) Wint., has been identified in a F2 population derived from an intraspecific cross between two wild pea (Pisum fulvum L.) accessions, IFPI3260 (resistant) and IFPI3251 (susceptible). Both parental lines and all the segregating population displayed a fully compatible interaction (high infection type), which indicates absence of hypersensitive response. Nevertheless, differences on the percentage of symptomatic area of the whole plant (disease severity) were observed. A genetic map was developed covering 1283.3 cM and including 146 markers (144 random amplified polymorphic DNA (RAPDs) and two sequence tagged sites (STSs) markers) distributed in 9 linkage groups. A QTL explaining 63% of the total phenotypic variation was located in linkage group 3. RAPDs markers (OPY111316 and OPV171078) flanking this QTL should allow, after their conversion in SCARs, a reliable marker-assisted selection for rust resistance. 相似文献
103.
The Pi‐ta gene in rice confers resistance to strains of the blast pathogen Magnaporthe grisea (Herbert) Borr. (anamorph Pyricularia oryza Cav.) containing the corresponding avirulence gene AVR‐Pita in a gene‐for‐gene fashion. The Pi‐ta gene is a typical nucleotide‐binding site type resistance gene. Nucleotide sequences distinguishing the resistant Pi‐ta and susceptible pi‐ta alleles were previously identified and used for developing DNA markers for a resistant Pi‐ta haplotype and three susceptible pi‐ta haplotypes. In the present study, the existence of the Pi‐ta gene in 141 rice germplasm accessions was rapidly determined using these markers, and the results were confirmed by inoculating rice germplasm with an M. grisea strain containing AVR‐Pita. The Pi‐ta gene was found in accessions from several major rice producing countries, including China, Colombia, Japan, Vietnam, the Philippines, Iran and the United States. The usefulness of DNA markers for rapid determination of the genotype of rice germplasm was thus demonstrated. The Pi‐ta gene also was found in rice cultivar known to contain the Pi‐ta2 gene, although the allelic relationship of these genes remains to be determined. The presence of the Pi‐ta gene in landrace cultivars in several different geographical locations, the Philippines and Vietnam, other indica rice cultivars in China and Colombia suggest that the Pi‐ta gene may have spontaneously originated in indica rice cultivars. These results are useful for incorporating the Pi‐ta gene into advanced breeding lines by marker‐assisted selection for rice breeding programmes worldwide. 相似文献
104.
A set of simple sequence repeat (SSR or microsatellite) markers was used to discriminate a collection of 33 Spinacia oleracea hybrid cultivars from seven different breeding stations all over the world. All SSR markers were genic microsatellite markers located in coding or non-coding regions of genes of known function. Cluster analysis based on 13 of the SSR markers showed that the spinach hybrids grouped into three clusters. The first two clusters consisted of European spinach types, which were well discriminated according to their origin from different breeding stations. The third cluster was a mixture of Asian as well as European types of spinach. Subclusters in this group did not reflect differences in morphology, earliness or company origin. The data show that genic microsatellites are a powerful tool for discrimination of spinach cultivars. 相似文献
105.
In the process of breeding triploid hop cultivars, diploid varieties need to be raised to the tetraploid level. Existing methods are predominantly based on treatment of the apices with antimitotic substances, in vivo or in vitro , resulting in a reported maximum of 26% tetraploids and a large proportion (over 60%) of mixoploids. This study was set-up to test whether an adventitious shoot regeneration protocol can be used as an alternative. In the first part of the experiments, regeneration media and a choice of explants (internodes, petioles and leaf discs) were optimized using three hop cultivars with putatively low, medium or high adventitious shoot regeneration capacity. On an optimized induction medium supplemented with 6 mg/l N 6 -(2-isopentenyl) adenine (2iP), a regeneration rate up to 17.7% was obtained from cultured internodes, even of the most recalcitrant 'Aurora', while the regeneration rate of the most responsive 'Tettnanger' was 56.9%. Flow cytometric analysis of ploidy level revealed a high frequency of tetraploid induction, the highest (58.6%) being in 'Savinjski golding'. In 616 regenerants of all three cultivars, 30.4% were found to be tetraploid, the others were diploid. Cytokinin content was found to be of minor importance in tetraploid induction. The high frequency of spontaneous tetraploid induction and, in particular, the complete absence of mixoploids makes this protocol an alternative to the currently established methods of chromosome doubling based on the use of antimitotic substances. The occurrence of a high proportion of tetraploid adventitious regenerants in hop is discussed in view of certain other biotechnological applications. 相似文献
106.
W. Li Z.-H. Yan Y.-M. Wei X.-J. Lan Y.-L. Zheng 《Journal of Agronomy and Crop Science》2006,192(3):221-227
An understanding of the characteristics of crop varieties and advanced lines could help improve their cultivation and to further enhance their potential. The objectives of this study were to estimate the genotype (G), environment (E) and genotype × environment (GE) interactions on the grain yield of Chinese spring wheat genotypes in 2000 and 2001 by the additive main effects and multiplicative interaction (AMMI) model, and to evaluate the relationships between yield and its components by correlation and path analysis. Grain yield varied from 3.9 to 5.2 t ha?1, among which SW8188 had the highest yield performance, followed by 58769‐6 and Chuannong 16. Three interaction principal components (IPC) accounted for a total of 79.99 % and 72.96 % of the interactions with 41.05 % and 52.08 % for the corresponding degrees of freedom in 2000 and 2001, respectively. When IPC3 was significant, the stability coefficient Di was more useful in the evaluation of the stability of each genotype. The estimates of Di in the 2 years indicated that the Di values varied between genotypes and years. The Di values ranged from 1.804 to 14.665 and 2.497 to 12.481 in 2000 and 2001 respectively. The suitable locations (environments) for all genotypes were characterized. These results would be useful for improving the Chinese spring wheat cultivation and improvement. 相似文献
107.
H. Z. Dong W. J. Li W. Tang Z. H. Li D. M. Zhang 《Journal of Agronomy and Crop Science》2006,192(2):132-139
Bt (Bacillus thuringiensis) transgenic cotton (Gossypium hirsutum L.), including the introduced, indigenous Chinese non‐hybrid and hybrid cotton, is spreading very rapidly in China. Agronomic and photosynthetic performance as well as the optimum plant density for planting Bt cotton may vary with genotypes. With three types of commercial Bt cotton varieties, two field experiments were conducted to study yield performance and leaf photosynthetic rate (Pn) during 2000 and 2001, and yield interaction between variety and plant density during 2001 and 2002 in Yellow River region in northern China. The first experiment showed that the indigenous Chinese Bt cotton significantly differed from the introduced Bt cotton (IBtC) in plant growth and yield components. As a result of manipulation of boll numbers, boll weight and lint percentage, there was no significant difference in lint yield between Chinese non‐hybrid Bt cotton (CBtC) and the IBtC, but two Chinese hybrid Bt cotton (HBtC) varieties exhibited significantly higher lint yield than all other varieties in either 2000 or 2001. Hybrid cotton SCRC15 showed a one‐peak curvilinear change in diurnal course of Pn throughout the growing season, while non‐hybrid cotton 33B and SCRC16 exhibited severe mid‐day depression in Pn in squaring, flowering or boll‐setting stage. The second experiment showed that the main effect of plant population on lint yield was not significant, and yield difference among all treatments was derived from varieties and the interaction between plant density and variety. The optimal plant densities in terms of lint yield for the introduced, indigenous CBtC and HBtC genotypes were 6.0, 4.5 and 3.0 plants m?2 respectively. 相似文献
108.
Guillermo Riesco Muñoz Óscar Santaclara Estévez Juan Gabriel Álvarez González Esther Merlo Sánchez 《European Journal of Forest Research》2014,133(4):623-630
The aim of this study was to establish the sources of variation in maritime pine wood properties related to appearance and strength, because of the importance of this wood in the sawing industry in Galicia (NW Spain). Ten trees from each of ten plots of the species (i.e., 100 trees) growing in Galicia were felled and sawn to produce the structural planks required for studying the presence of external strength-reducing characteristics. The planks were sampled from the basal logs to 16 m height in the stems, yielding cross sections of target dimensions 100 × 40 mm to 200 × 200 mm. We propose a model in which individual tree height and dominant height are used to predict the knottiness of planks from trees in mature stands. The abundance of externally visible knots on faces and edges of sawn planks is therefore more dependent on the stand location than on the prior silvicultural treatment of the stand. 相似文献
109.
Bernabéu JA Torres-Suárez AI Gil-Alegre ME Camacho MA 《Journal of agricultural and food chemistry》2000,48(12):5969-5974
The objective of this paper was to study the stability of a medicated premix and a medicated farm feed containing sulfadimidine as the active ingredient. The medicated premix is supplied as powdered form and administered orally after mixing with animal feed. The sulfadimidine analytical method described in United States Pharmacopoeia 23 cannot be used to carry out the stability study because of its lack of specificity for different degradation products. Therefore, a high-performance liquid chromatography method was developed to assay sulfadimidine. This method was optimized and validated for the stability study. According to International Committee Harmonization (ICH) guidelines, the samples were stored under long-term testing and accelerated conditions for the stability study of the premix and the medicated farm feed. Sulfadimidine degradation was not detected in either form under any of the conditions studied. 相似文献
110.
Anne-Sophie Sergent Nathalie Bréda Léopoldo Sanchez Jean-Charles Bastein Philippe Rozenberg 《Annals of Forest Science》2014,71(6):709-720