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101.
É. Darkó J. Fodor S. Dulai H. Ambrus A. Szenzenstein Z. Király B. Barnabás 《Journal of Agronomy and Crop Science》2011,197(6):454-465
To improve the abiotic stress tolerance of maize (Zea mays L.), doubled haploid (DH) plants were produced by in vitro selection of microspores exposed to tert‐butyl hydroperoxide (t‐BuOOH) as a powerful prooxidant This study investigated the tolerance of the progenies of t‐BuOOH‐selected DH lines to oxidative stress, cold and drought in controlled environment pot experiments by analyses of photosynthetic electron transport and CO2 assimilation processes, chlorophyll bleaching and lipid peroxidation of leaves. Our results demonstrated that the t‐BuOOH‐selected DH plants exhibited enhanced tolerance not only to oxidative stress‐induced by t‐BuOOH but also to cold and drought stresses. In addition, they showed elevated activities of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase and glutathione S‐transferase when compared with the DH lines derived from microspores that were not exposed to t‐BuOOH and to the original hybrid plants. The results suggest that the simultaneous up‐regulation of several antioxidant enzymes may contribute to the oxidative and cold stress tolerance of the t‐BuOOH‐selected DH lines, and that the in vitro microspore selection represents a potential way to improve abiotic stress tolerance in maize. 相似文献
102.
Global temperature is rising because of increasing concentrations of CO2 and other greenhouse gases (e.g. methane, nitrous oxide, etc.) in the atmosphere because of the excessive use of fossil fuels. High temperature causes heat stress which reduces crop productivity. The development of heat-tolerant varieties is feasible and will help mitigate the effects of climate change. Fifty-one cotton accessions were screened in heat-stressed and non-stressed conditions in the glasshouse and field. Relative cell injury percentage (RCI %), a measure of cell membrane thermostability (CMT), was used to assess heat tolerance. Heat-tolerant accessions had more stable yield and yielded more seed cotton with better quality fibre than the heat-intolerant accessions across four environments. The responses of the 51 accessions to all four environments for the measured traits were strongly associated. RCI % of the accessions and hybrids was strongly and negatively associated with yield and fibre traits. CMT was concluded to be a useful technique for identification of heat-tolerant cotton. 相似文献
103.
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
104.
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
105.
The Lr56/Yr38 translocation consists primarily of alien-derived chromatin with only the 6AL telomeric region being of wheat origin. To improve its utility in wheat breeding, an attempt was made to exchange excess Ae. sharonensis chromatin for wheat chromatin through homoeologous crossover in the absence of Ph1. Translocation heterozygotes that lacked Ph1 were test-crossed with Chinese Spring nullisomic 6A tetrasomic 6B and nullisomic 6A-tetrasomic 6D plants and the resistant (hemizygous 6A) progeny were analyzed with four microsatellite markers. Genetic mapping suggested general homoeology between wheat chromosome 6A and the translocation chromosomes, and showed that Lr56 was located near the long arm telomere. Thirty of the 53 recombinants had breakpoints between Lr56 and the most distal marker Xgwm427. These were characterized with additional markers. The data suggested that recombinants #39, 157 and 175 were wheat chromosomes 6A with small intercalary inserts of foreign chromatin containing Lr56 and Yr38, located distally on the long arms. These three recombinants are being incorporated into adapted germplasm. Attempts to identify the single shortest translocation and to develop appropriate markers are being continued. 相似文献
106.
Y. X. He T. Q. Zheng X. B. Hao L. F. Wang Y. M. Gao Z. T. Hua H. Q. Zhai J. L. Xu Z. J. Xu L. H. Zhu Z. K. Li 《Plant Breeding》2010,129(2):167-175
107.
Lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis cis- -pentadiene structure producing hydroperoxy acids with conjugated dienes.…… 《分子植物育种》2007,5(2):188-189
Lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis, cis-1,4-pentadiene structure producing hydroperoxy acids with conjugated dienes. LOX activity has been found in a wide range of plants. Typical substrates for LOX in plants are linoleic acid and linilenic acid fatty acids. The function of various LOXs in plants is unknown, but their participation in all stages of plant growth and development has been suggested （Hildebrand, 1989; Siedow, 1991）. Some of the physiological processes in whicn lipoxygenses have been implicated include wounding （Saravitz and Siedow, 1996）, pathogen attack （Melan et al., 1993）, seed germination （Kato et al., 1992）, fruit ripening （Ferrie et al., 1994）, plant senescence （Paliyath and Droillard, 1992）. The study on the role of lipoxygenase in ripening and senescence fruit focused on tomato and strawberry. Cloning LOX gene of cucumber fruit will make us further understand the molecularaction mode of this enzyme during fxuit ripening and senescence. In this paper we isolated the partial nucleotide sequences of cucumber fiuit lipoxygenase gene and discuss the characterization of it. 相似文献
108.
Á. Jerzsele Z. Karancsi E. Pászti‐Gere Á. Sterczer A. Bersényi K. Fodor D. Szabó P. Vajdovich 《Journal of veterinary pharmacology and therapeutics》2018,41(3):409-414
Xylitol is commonly used as sugar substitute in households. While it has numerous beneficial effects on human health, it is highly toxic to dogs. The goal of this study was to examine whether xylitol has similar deleterious effects, such as hypoglycaemia and acute hepatic failure, on cats. Our research included six healthy middle‐aged cats. Xylitol was dissolved in deionized water and administered p.o. at three doses (100, 500 and 1,000 mg/kg body weight). These dosages have been considered toxic and can cause liver failure or even death in dogs. After every xylitol administration, the basic health status and the blood glucose of cats were observed regularly. Additionally, prior to and 6, 24 and 72 hr after xylitol administration, blood samples were taken to check complete blood count, clinical biochemical parameters and enzymes such as ALT, ALKP, GGT, GLDH, bile acids, BUN, creatinine, phosphate, total protein, albumin, sodium and potassium. There were no significant changes (p > .05) in any of the haematological or biochemical parameters. Blood glucose concentrations did not show any significant alterations, except at 1,000 mg/kg dose, where a mild but significant increase was observed, but it was in physiological range. Based on our results, xylitol did not induce toxic effects on cats. 相似文献
109.
Random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers were used to estimate the genetic relationships among 101 soybean cultivars developed in north‐eastern China. Fifty‐three fragments of the 100 RAPD markers and 35 SSR markers tested were polymorphic across the 101 soybean cultivars. Similarity values among these soybean cultivars ranged from 45.2% to 100% for RAPD data, and ranged from 36.1% to 100% for SSR data. The similarity matrices for SSR data and RAPD data were moderately correlated (r = 0.31, P < 0.05). Cluster analyses indicated that the cultivars released from the same seed company were mostly grouped together. A principal component analysis, based on the combined RAPD and SSR data, yielded a good separation of soybean varieties with different maturity ratings [represented by soybean Heat Unit (HU)]. The varieties with HU < 2200 were well separated from those with HU > 2200. Four RAPD markers and eight SSR markers were significantly associated with the maturity ratings of soybean. 相似文献
110.
Pre-harvest sprouting (PHS) reduces the quality of wheat (Triticum aestivum L.) and the economic value of the grain. The objective of this study was to evaluate the diversity of the Viviparous-1B (Vp-1B) gene associated with PHS tolerance in a collection of 490 widely grown winter wheat varieties from central and northern Europe. Four alleles of Vp-1B were found in the wheat varieties tested, three of which (Vp-1Ba, Vp-1Bb and Vp-1Bc) had previously been identified in Chinese wheat varieties. The fourth was a new allele which had a 25-bp of deletion in the third intron region compared with the nucleotide sequence of Vp-1Ba, and was designated as Vp-1Bd. The frequencies of different alleles in this set of European wheat germplasm were: Vp-1Ba (54%) > Vp-1Bc (21%) > Vp-1Bd (20%) > Vp-1Ba + c (4%) > Vp-1Bb (1%), with Vp-1Bb being present only in two French varieties, ‘Altria’ and ‘Recital’. In addition, the frequencies of the alleles differed in varieties from different European countries. For example, Vp-1Ba had the highest frequency (76%) in varieties included in the UK National List (NL), but was least frequent in the Recommended List (RL) of Sweden (19%). Similarly, Vp-1Bc was present with the highest frequency (58%) in wheat varieties from Sweden, and the lowest in UK NL varieties (8%) while Vp-1Bd had the highest frequency of 32% in German varieties, and the lowest in Sweden varieties with only 8%. The Vp-1Ba allele was present in over half of the UK wheat varieties tested but the frequency was lower in RL varieties than in NL ones. Furthermore, heterogeneities were found between Vp-1Ba and Vp-1Bc in the varieties from Sweden, Netherlands, Germany and UK. 相似文献