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41.
Carbon dioxide (CO2) concentration in greenhouses is sub-optimal for vegetable production. Many techniques have been used to increase CO2 concentration in greenhouses but most of them are expensive with certain limitations and drawbacks. We adopted a new strategy to elevate CO2 concentration in the greenhouse throughout the day via crop residues and animal manure composting (CRAM). During the whole cultivation period, CRAM-treated greenhouse had doubled CO2 concentration which significantly increased the yield of cherry tomatoes (Solanum lycopersicum L.), i.e., up to 38%. The influence of CRAM procedure on cherry tomato quality was also investigated and the concentrations of total soluble solids (TSS) and soluble sugar were found to be significantly higher in cherry tomatoes grown under composting greenhouse than that of non-composting greenhouse. Additionally, CRAM-CO2 enrichment also resulted in increased concentrations of ascorbic acid (Vitamin C) and titrate acid as compared to control. In contrast, the concentration of nitrate was considerably decreased in cherry tomato grown under CO2 enriched condition than that of control. The increase in active oxygen metabolisms such as POD, CAT and SOD while a decrease in MDA, as well as APX was observed for cherry tomatoes grown under CO2 enriched condition. Hence, CO2 fertilization by using CRAM in greenhouse significantly improved quality and increased the yield of cherry tomatoes.  相似文献   
42.
Determining degree-day thresholds from field observations   总被引:6,自引:0,他引:6  
 This paper compares several methods for determining degree-day (°D) threshold temperatures from field observations. Three of the methods use the mean developmental period temperature and simple equations to estimate: (1) the smallest standard deviation in °D, (2) the least standard deviation in days, and (3) a linear regression intercept. Two additional methods use iterations of cumulative °D and threshold temperatures to determine the smallest root mean square error (RMSE). One of the iteration methods uses a linear model and the other uses a single triangle °D calculation method. The method giving the best results was verified by comparing observed and predicted phenological periods using 7 years of kiwifruit data and 10 years of cherry tree data. In general, the iteration method using the single triangle method to calculate °D provided threshold temperatures with the smallest RMSE values. However, the iteration method using a linear °D model also worked well. Simply using a threshold of zero gave predictions that were nearly as good as those obtained using the other two methods. The smallest standard deviation in °D performed the worst. The least standard deviation in days and the regression methods did well sometimes; however, the threshold temperatures were sometimes negative, which does not support the idea that development rates are related to heat units. Received: 26 May 1998 / Accepted: 28 October 1998  相似文献   
43.
Birch pollen-related food allergies are mainly associated to Bet v 1. Little is known about isoforms of Bet v 1 homologous in fruit of the Rosaceae family. We attempted to identify novel isoforms of Pru av 1, the major cherry allergen, at the cDNA and the protein level by a combination of molecular biology and proteomic tools. A cDNA library was screened with patients immunoglobulin E (IgE) and a specific hybridization probe. Edman sequencing, mass spectrometry (MS), and MS/MS were performed after detecting Pru av 1 on 2-D maps by immunoblotting using patients IgE and a monoclonal antibody. Partial amino acid sequences were completed with a polymerase chain reaction (PCR) strategy. The IgE-binding properties of the Pru av 1 spots were analyzed by 2-D blot inhibition. cDNA library analysis revealed a novel Pru av 1 isoform. MS and N-terminal sequencing confirmed the cDNA sequences at the protein level. A series of spots were confirmed as the already known Pru av 1. One spot, exclusively detected with patients sera, was identified as the novel isoform. A partial amino acid sequence detected with MS/MS was completed by PCR-cloning. The 2-D blot inhibition revealed epitope differences between the novel isoform and the previously published Pru av 1. Our data demonstrate that a synergistic combination of molecular biology and proteomics represents a powerful tool for reliable and comprehensive identification of allergen isoforms and variants. The newly identified isoform showed diverging IgE-binding properties and may be relevant for the diagnosis or therapy of cherry allergy.  相似文献   
44.
抗菌肽基因转化樱桃矮化砧木获得抗根瘤病的转基因植株   总被引:22,自引:0,他引:22  
建立了樱桃(PrunuspseudocerasusLindl.)矮化砧木茎尖高频再生系统,并利用根癌土壤杆菌(Agrobacteriumtumefaciens(SmithetTownsend)Conn)介导将gus及抗菌肽基因导入樱桃矮化砧木,获得19个转化株系。经Southernblot检测证明,抗菌肽基因已整合到樱桃的基因组。转基因植株接瘤实验、gus基因表达产物的颜色反应及叶片提取液对根癌土壤杆菌C58的抑菌实验表明,抗菌肽基因在转化植株中可能已得到有效表达,试管苗具有明显的抗根瘤病特性。还研究了茎尖分生组织的种质转化特点,结果表明它是一个较好的转化系统,可获得较高的转化频率。  相似文献   
45.
本文报告通过茎尖培养及试管苗嫁接快速繁殖甜樱桃新品系13-38苗木。取新品系母树休眠芽制备成无菌外植体,分别在MS附加6-BA 0.1-0.5mg/l,IAA 0.1mg/l培养基及MS附加ZT1—1.5mg/l,IAA 0.1—0.25mg/l培养基中进行微型扦插及茎尖分化培养,建立茎尖无性系。试管苗年扩繁量为4~8和10~3。以新品系试管苗为接穗,采用切接,皮接两种方法嫁接于四种砧木,成活率为20—70%不等。实验表明13-38试管苗与砧木新品系1090试管幼苗的亲和力较好。接合部位预先施用200ppm的NAA可提高嫁接成活率。  相似文献   
46.
47.
Characterisation of novel S-alleles from cherry (Prunus avium L.)   总被引:1,自引:0,他引:1  
In plant populations exhibiting gametophytic self-incompatibility, individuals harbouring rare S alleles are likely to have a reproductive advantage over individuals having more common alleles. Consequently, determination of the self-incompatibility haplotype of individuals is essential for genetic studies and the development of informed management strategies. This study characterises six new S alleles identified in wild cherry (Prunus avium L.). Investigations to determine the S genotype of individuals in recently planted woodland through length polymorphisms of introns associated with the stylar S-RNase gene and the pollen SFB gene revealed six S intron profiles which did not correspond to those of known S alleles. These are now attributed to S 27 to S 32 . Consensus primers, annealing in the S-RNase sequence coding for the signal peptide and C5 regions, were used to isolate the S-RNase alleles associated with the novel S intron profiles. The proteins corresponding to the new alleles were separated by isoelectric focusing from stylar extracts and their pI values determined. Similarities between the deduced amino acid sequence for the new alleles isolated and other cherry S-RNase sequences available on the databases ranged from 40% to 86%. Amplification products for SFB introns ranged from 172 to 208bp. New sequence regions exposed to positive selection were identified and the significance of the PS3 region reinforced. A phylogenetic relationship between P. avium S-RNases for S 10 and S 13 and between corresponding SFB alleles may indicate co-evolution of allele specificities of these two genes. The nucleotide sequences reported in this paper have been submitted to the EMBL/GenBank database under the following accession numbers: S 27 (DQ266439), S 28 (DQ266440), S 29 (DQ266441), S 30 (DQ266442), S 31 (DQ266443), S 32 (DQ266444).  相似文献   
48.
都江堰林区取食樱桃果实(种子)的鸟类及其种子扩散作用   总被引:1,自引:0,他引:1  
樱桃(Prunus pseudocerasus)是广泛分布于我国亚热带常绿阔叶林内的一种重要核果植物。为了解食果鸟类在樱桃种群更新中的作用,于2007年和2008年在四川都江堰亚热带常绿阔叶林内研究了取食樱桃果实(种子)的鸟类及其种子扩散作用。研究表明,樱桃成熟果实的下落高峰发生在4月下旬至5月上旬;2007年的种子扩散率为4.0%±1.0%,明显低于2008年(27.7%±5.7%)。在研究地内,发现至少有16种鸟取食樱桃果实或种子,根据其对果实和种子的处理方式分为3个功能群:白头鹎(Pycnontus sinensis)、领雀嘴鹎(Spizixos semitorques)、黑鹎(Hypisipetes leucocephalus)、白颊噪鹛(Garrulax snnio)、红嘴蓝鹊(Urocissa erythorhyncha)等10种鸟吞食樱桃果实,而种子通过消化道末端排出并将种子携至远离母树的地方,是重要的种子扩散者;暗绿绣眼鸟(Alcippe morrisonia)和灰眶雀鹛(Zosterops iaponicus)等4种鸟主要啄食果肉而将种子丢弃在母树下,为啄食果肉者;而普通朱雀(Carpopacus erythrinus)和灰头鸦雀(Paradoxornis gularis)则主要取食种子,为纯粹的种子捕食者。在吞食樱桃果实的食果鸟中,3种鹎科鸟类访问频次所占的比例达55.3%(2007年)和35.3%(2008年),说明鹎科鸟类是都江堰林区樱桃种子的主要扩散者,对樱桃种群的空间格局和自然更新可能有重要影响。  相似文献   
49.
Analysis of two cherry progenies from semi-compatible crosses for the esterase enzyme system showed extremely distorted segregation ratios for Est-5. Analysis of two progenies from compatible crosses for esterase and for stylar ribonuclease proved that Est-5 is linked with the incompatibility locus S. The recombination fraction is 4%. About a fifth of some 50 cultivars or selections genotyped for Est-5 were heterozygous. The various heterozygotes could provide ’testers’ for the presence in cultivars of unknown genotype of 8 of the 11 known S alleles. A seedling suitable for testing S 9 has been identified and crosses have been made to raise testers for S 10 and S 11 . Isoenzyme analysis of the four progenies for glutamate oxaloacetate transaminase, and of one of them for isocitrate dehydrogenase, showed no evidence for the linkage of Got-1 or Idh-2 with S, contrary to a previous report. Estimation of linkage with S in semi-compatible crosses is discussed. Received: 16 April 1999 / Accepted: 22 June 1999  相似文献   
50.
External and internal tomato irregular ripening (TIR) symptoms were associated with the feeding of silverleaf whitefly (SLW), Bemisia argentifolii Bellows and Perring. Four experiments consisting of various soil drench applications of GA3 (100 ppm) and cycocel (CCC, an inhibitor of GA biosynthesis; 1,000 and 2,000 ppm) were applied to dwarf cherry tomato cv. Florida Petite in the presence and absence of SLW in an attempt to mimic the disorders induced by the SLW. The application of GA3 induced external and internal TIR symptoms similar to the SLW-induced disorder. Minimal TIR-like symptoms also occurred in the control and CCC treatments. Internal TIR symptoms in GA3, GA3 plus SLW, and GA3 plus CCC treatments ranged from 66% to 97% throughout the experiments. The incidence of external TIR symptoms was highest in the GA3 plus SLW treatment compared with the other treatments. CCC reduced the incidence of external TIR symptoms induced by GA3 or GA3 plus SLW treatments. However, CCC-treated plants also attracted more oviposition and higher populations of SLW and consequently induced a greater incidence of TIR symptoms than SLW treatment alone. Furthermore, although low SLW populations may be associated with low external TIR symptoms, internal TIR symptoms almost always remained high in infested plants. The results suggest that the TIR disorder in dwarf cherry tomato which is induced by the SLW may be a gibberellin-regulated disorder. Received May 27, 1997; accepted September 26, 1997  相似文献   
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