查看更多>>摘要：Traditional seed-coating agents are widely used,and their accumulative toxicity in soil brings a great hazard to natural environment and human health.In this study,a novel cucumber seed-coating agent was prepared from natural polysaccharide,fertilizer and microelement,etc.Results indicated that the agent had an excellent control effect on pests and increased yield by 8.5％ to 9.3％,while the material cost was decreased by 16.7％ compared with the traditional toxic seed-coating agent.In addition,the toxicity of the novel agent was also lower than that of traditional ones.Therefore,the application of the novel agent for cucumber is an appropriate option for controlling pests and replacing high toxicity ones.
查看更多>>摘要：The timing of floral transition is tightly controlled by a combination of endogenous and environmental signals.One early flowering mutant plant was screened from Arabidopsis library of T-DNA insertion to accelerate flowering under short-day condition,and a related-gene EFS1 (AT4G36680.1) was isolated and identified as a novel flowering-time gene of Arabidopsis in our preliminary studies.To investigate the function and the specific mechanism of EFS1 in the flower process control,the RNAi expression vector containing EFS1 gene-specific sequences in the sense and antisense orientations was constructed and transferred into Arabidopsis by using the floral-dip method,with 11 transgenic plants obtained through hygromycin B screening and PCR assays.The results showed that the expression level of EFS1 in transgenic fines was significantly lower than that in wild type and efsl mutant.The flowering time of the efs1 mutant and RNAi transgenic plants was much earlier than that of wild-type plants.This result further verified that the EFS1 gene played an important role in flowering,and its specific mechanisms need further study.These work provided a foundation to further regulatory mechanisms of EFS1 in the control of floral transition.
查看更多>>摘要：Botrytis cinerea is one of the important phytopathogenic fungi.Cloning of the genes related to their development and pathogenicity is fundamental to the pathogen control.A mutant (BCt160),which produces abnormal conidia and no sclerotia,was identified from Botrytis cinerea mutant library generated by Agrobacterium tumefaciensmediated transformation (ATMT).Southern blotting analysis showed that one T-DNA insertion occurred in the genome of the mutant.TAIL-PCR (thermal asymmetric interlaced PCR) and bioinformatic analysis indicated that the exogenous T-DNA insertion occurred in the second exon of a putative gene BC1G_12388.1,named as BcDR1 (B.cinerea development-related gene 1).The function analysis of BcDR1 gene showed that the BcDR1 was related to development,morphological differentiation,and pathogenicity of B.cinerea,suggesting that BcDR1 gene was required for the development and pathogenicity of B.cinerea.
查看更多>>摘要：Tea is an important economic crop in China.About 2665 accessions of tea germplasm (Camellia spp.) are conserved in the China National Germplasm Tea Repository.However,only a small fraction of the collections have been exhaustively used in tea plant improvement programs.The objective of the present study was to develop a core collection of tea plant to enhance the utilization of genetic resources in improvement programs and simplify their management.For this purpose,based on the cultivated region grouping and phenotypic trait data,a core collection of tea plant was established using logarithm proportion and Ward's cluster method.Approximately 20％ of the accessions were then randomly selected from these distinct groups to form a core collection of 532 accessions.Different statistical methods including comparison of mean using Newman-Keuls test,variance using Levene's test,and frequency distribution using Chi-square test for the traits validated that the variation present in the initial collection was retained in the core collection.The Shannon-Weaver diversity index for different traits was also similar in the core and initial collection.The phenotypic correlations among different quantitative traits that may be under the control of coadapted gene complexes were also preserved in the core collection.This core collection will play an important role in the utilization of tea germplasms.
查看更多>>摘要：The occurrence of fruit shrink disease in Ziziphus jujuba Mill.‘Linyilizao' was investigated from 2006 to 2009 in Cangxian of Hebei Province,Taiyuan,and Taigu of Shanxi Province,and the pathogens were isolated from the diseased fruits sampled from both Cangxian and Taiyuan in 2006 and 2007.The pathogens in leaf,fruit,and shoot collected from Cangxian were isolated from June to October in 2008 at 30-day intervals.The incidence of the disease varied significantly with location and year,and the highest incidence was observed in Cangxian during 2006.Three kinds of key pathogens were isolated from the fruits from July to September,i.e.,Alternaria alternata Keissler (mainly in July),Phoma destructiva Plowr.(mainly in September),and Fusicoccum sp.,of which A.alternata was the most dominant.In leaves,both A.alternata (much more dominant) and P.destructiva could be isolated throughout June to October,but no Fusicoccum sp.was found.At the white-ripening stage of fruit,the isolation rate of A.alternata was the highest in leaves (36.67％),followed by extension shoot (6.67％) and fruit (1.11％) while that of P.destructiva was the highest in extension shoot (31.11％),followed by fruit (13.33％) and leaf (12.22％),with Fusicoccum sp.isolated only in extension shoot (2.22％).The frequency of isolating two or three kinds of above three pathogens together was very low,with the highest rate (19.30％) found in A.alternata and P.destructiva from leaves in July.
查看更多>>摘要：The postharvest physiology of strawberry was investigated to study the effects of ozone on weight loss rate,ascorbic acid,respiration rate,peroxdase (POD) activity,catalase (CAT) activity,and malondialdehyde (MDA) content during cold storage.The strawberries were treated with ozone of 0 ppm (control),2 ppm,4 ppm,and 8 ppm,respectively.The results indicated that the treatment of 4 ppm ozone could inhibited the decrease of ascorbic acid,POD activity,and CAT activity,and reduced weight loss rate and MDA content.The treatment delayed the senescence of strawberry,with a significantly lower respiration rate.Thus,the best concentration of ozone was 4 ppm,and ozone treatment could be a good candidate for maintaining postharvest quality of strawberry and provide a longer storage life.
查看更多>>摘要：Intracellular signal transduction pathways including MAPK,Ca2+,and cAMP signal transduction pathways play important roles in regulating growth,development,and pathogenesis of phytopathogenic fungi.Protein kinase A (PKA) is a key enzyme in cAMP signaling pathway.The transcription level of the gene encoding catalytic subunit of PKA in Setosphaeria turcica under different culture conditions was analyzed by the semiquantitative RT-PCR method.The expression level of PKA-c gene was the lowest on the medium containing sucrose and starch as the carbon source,and it was distinctly inhibited by Cu2+,but it was independent of nitrogen source.After the addition of different concentrations of sorbitol,it showed the positive correlation between the inhibition affection and concentrations.However,the highest expression was observed in response to NaCl (0.9 mol/L).This research enriched the biological information resource of filamentous fungi and laid a foundation for the functional analysis about signal transduction pathway in phytopathogenic fungi.
查看更多>>摘要：The existence of a long juvenile phase is found seriously to affect the early-stage economic benefits of later mature walnuts (Juglans regia L.).Studies on LFY,a key gene controlling floral transition and flower differentiation,may be helpful in solving the problem.This study reports the identification and characterization of a JrLFY gene from Juglans regia L.,a homolog of FLORICAULA/LFY.The gene was isolated from flower buds of precocious walnut cultivar Zhonglin No.5 by RT-PCR and RACE.The cDNA sequence of JrLFY (GenBank accession no.GU194836) was 1496 bp and contained an ORF of 1158 bp.Its corresponding genomic sequence (GenBank accession no.HQ019159) showed that the JrLFY contained three exons and two introns.The predicted amino acid sequence of the gene consisted of 385 amino acids and had a conserved region in the C-terminal when being aligned with sequences of other LFY homologs.Phylogenetic analysis showed that the LFY protein of walnut was close to those of hickory and chestnut.These studies will lay a foundation for understanding the mechanism of early fruiting and preparation for transfer of the JrLFY as a transgene to later mature walnuts.
查看更多>>摘要：To study the effect of foliar application of urea fertilizer on the growth and yield of tomato and to find out the optimum concentration of foliar application of urea for maximum growth and yield of tomato,an experiment was conducted with different concentrations of foliar application of urea fertilizer,namely,2500,5000,7500,and 10000 ppm.The experiment was laid out by a randomized complete block design (RCBD) with four replications.Results showed that different yield components and yield of tomato were influenced by the foliar application of different concentrations of urea.The maximum plant height (132.6 cm),number of leaves (30.73),number of green leaves per plant at harvest (21.08),days to first flowering (28.94),number of flower clusters (11.89),number of flowers (75.18),fruit clusters (5.81),fruits per cluster (4.14),and fruits per plant (21.49); length (4.72 cm),diameter (6.58 cm),and weight of individual fruit (151.0 g) were significantly influenced by the 10000 ppm concentration of foliar application of urea fertilizer.The 10000 ppm application gave the highest yield (63.69 t/hm2) with the lowest (28.48 t/hm2) in the control treatment.The yield per plant as well as per hectare increased with increasing concentrations of foliar application of urea fertilizer.
查看更多>>摘要：Soluble dietary fiber (SDF) is an extract from spent residue of Cornus officinalis Sieb.et Zucc fruit by ultrasonic.The conditions of the experiment optimized with response surface methodology were ambient temperature of 70.3℃,the ratio of solvent to solid being 30 mL/g,and processing time of 110 min under the ultrasonic wave frequency of 40 kHz and ultrasonic power of 250 W.The best aggregative indicator,incorporating the yield of Cornus SDF (CSDF),the content of SDF,and light transmittance (％,at 620 nm) of SDF,was predicted to be 12.7845 according to the fitting equation.After UV sterilization,0.25％ (w/v) dispersion of CSDF in mineral water presented a good light transmittance (94.9％) and shelf-life (over 2 months).It had no smell and tasted good.The left residue was extracted with caustic soda to get hemicellulose.
NETL
NSTL
万方数据