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1.
DREB1/CBF类转录因子在植物抵抗外界胁迫上起重要作用,利用这些基因改良作物抗逆性具有重要意义。本研究在白菜中分离到一个DREB类转录因子基因BpDREB1 (EF219470)。该基因序列全长647 bp,推测编码蛋白含213个氨基酸,相对分子量为23 kD,理论等电点为5.11,与白菜中该类转录因子序列同源性为94%。进化树表明,BpDREB1属于DREB亚家族中A1亚族。基因的诱导表达模式分析显示,BpDREB1被低温强烈、迅速诱导表达,并对干旱胁迫也有一定程度的响应,但对高盐处理几乎没有响应。过表达BpDREB1的转基因拟南芥经低温诱导后,其体内可溶性糖及脯氨酸含量大幅度提高。以上结果显示BpDREB1转录因子基因具有家族成员基因结构的特征,在低温、干旱应答途径中起重要作用。  相似文献   
2.
Efforts in grasspea (Lathyrus sativus) improvement have increased since the development of lines that are very low in the neurotoxin Beta-N-oxalyl-L-alpha-beta-diamino propionic acid (ODAP); also referred to as Beta-N oxalyl-amino-L-alanine (BOAA). Many programs now address several related aspects of improvement simultaneously. These include reduced ODAP concentrations, insect and disease resistance, nitrogen fixation, agronomic practices, fodder and forage production, and components for increased yielding ability. The coordinated, multidisciplinary approach now being applied to the genetic improvement of grasspea should allow the potential of this largely neglected grain legume to be fully realized.  相似文献   
3.
为探求适合河南省花生产区磷与有机肥合理的配施比例,采用田间试验研究不同磷用量(45、90和135 kg/hm2)与有机肥用量(0.75、1.50和2.25 t/hm2)配施对花生产量及磷素吸收、土壤Hedley各磷素形态含量与分配及磷酸酶活性的影响。结果表明,相同磷用量下,与2.25 t/hm2有机肥用量相比,0.75和1.50 t/hm2有机肥用量下,花生产量显著提高8.2%~11.8%,地上部干物质重显著降低17.1%~64.3%;相同有机肥用量下,增施磷肥显著增加花生地上部生物量,但对产量无显著影响。花生不同部位磷含量对磷与有机肥配施的响应表现为,中高量有机肥和磷肥处理分别显著高于低量有机肥和磷肥处理,而中量和高量有机肥、磷肥处理间差异因植株部位不同而异。土壤不同磷组分对磷与有机肥的响应存在差异,其中活性磷组分(H2O-P和NaHCO3-Pi)和中等稳定性磷组分(NaOH-Pi和NaOH-Po)含量随磷肥与有机肥用量增加而增加,土壤稳定性磷组分(HCl-P和Residual-P)随磷肥与有机肥用量变化差异不显著。有机肥和磷肥对土壤磷酸酶的影响不同,增加有机肥能显著提高土壤磷酸酶活性,但增施磷肥抑制土壤磷酸酶活性。综合而言,磷肥与有机肥合理配施能显著提高花生产量、花生各部位磷素含量、土壤活性磷含量及土壤磷酸酶活性,过量施用有机肥和磷肥均可造成花生营养生长过旺,产量下降,还不利于提高花生体内磷含量。本试验条件下在施用45 kg/hm2磷肥基础上配施0.75~1.5 t/hm2的有机饼肥有利于改善土壤-花生系统磷素营养,促进花生产量提高,可在豫南砂姜黑土花生种植区示范应用。  相似文献   
4.
There are no standardized procedures for sanitizing orchid seeds for propagation by tissue culture and there is insufficient information about the optimum stage of orchid seed development for best germination. Phalaenopsis amabilis flowers were hand-pollinated and fruits harvested 90, 105, and 120 d after pollination (DAP) for seed developmental analysis. Embryo cell number per seed was counted after staining with 4′-6-diamidino-2-phenylindole and viewing through a confocal microscope. Germination percentage and cell number per embryo increased from 14 to 61% and 41 to 66%, respectively, during fruit development from 90 to 120 DAP. Seeds from mature, browning (∼140 DAP) Phalaenopsis Sogo Lit-Angel and Phalaenopsis spp. breeding line 9450 seed pods failed to germinate until frozen at −196, −80, or −18 °C and thawed or chilled at 4 °C for 10 d. Germinability in 140 DAP seeds was correlated with cracked testa after freezing and thawing. P. amabilis seeds were treated with 0, 5, 10, or 15% calcium hypochlorite (CH) for 5, 10, or 15 min. Ninety six percent of untreated seeds from 90 DAP fruit produced protocorms within 40 d after sowing (DAS). Exposing seeds to 5% CH for 10 or 15 min decreased germination to 85 and 73%, respectively. Exposure to 10 or 15% CH for 5, 10, or 15 min produced seed germination percentages of less than 40%. Protocorms developed root hairs and shoot primordia by 50 DAS and an average of one leaf and root by 85 DAS after treatment with either 0 or 5% CH. Higher concentrations delayed or inhibited protocorm development. Green fruits 120 DAP produced the highest percentage of protocorms, while ∼140 DAP seeds from browning fruit were dormant but cold treatments increased germination.  相似文献   
5.
彭方仁  黄宝龙 《林业研究》1999,10(3):163-167
lntroductionCoconut(Cocosnucifera)isanimportanteconomicplantinthetropicalareas.Butinthetraditionalcoconutplantation,theroutinespaceintherowsis7.5mX7.5m.Sothefieldareasabout75%werenotefficientlyused.Inrecentyears,Indonesiahasmadegreateffortstodevelopanagroforestrysystemofcoconutinterplantedwithpineapple(Satyabalan1986).Asthepineapplehasacertainamountofshade-resistance,thissystemcannotonlymakefulluseofthesoilresources,butalsogreatlyimprovethebiomassproductivityofthewholesystem.Buttheresearchab…  相似文献   
6.
施氮量对不同花生品种生长及干物质积累的影响   总被引:9,自引:0,他引:9  
研究了施氮量对不同花生品种生长和干物质积累的影响.结果表明,施用氮肥可促进花生的生长和干物质积累,不同品种对氮肥的响应存在明显差异,当施氮量为N112.5 kg/hm2时,白沙1016和鲁花12号的总分枝数和结果枝数达到最大值,而远杂9102达到最大值时需要的施氮量仅为N 75 kg/hm2.花生干物质总量的积累动态符...  相似文献   
7.
The alphavbeta3 and alphavbeta5 integrins are known as transmembrane receptors capable of binding to the RGD amino acid peptide sequence. In mouse early gonadogenesis, some proteins containing the RGD sequence are deposited into extracellular space and participate in morphogenesis. We analyzed the expression patterns of the alphavbeta3 and alphavbeta5 integrins in mouse developing gonads (10.5-13.5 days post coitum) using whole-mount in situ hybridization. The alphav integrin mRNA was homogenously expressed in developing gonadal regions. On the other hand, the beta3 integrin mRNA was found only in large and round cells (presumptive germ cells), whereas beta5 integrin was localized in gonadal somatic cells, with the exception of coelomic epithelial cells. The beta3 integrin-expressed cells were determined to be primordial germ cells because the number of these cells was drastically reduced in busulfan-treated gonads. In this study, we demonstrated that the alphavbeta3 and alphavbeta5 integrins are widely localized in the mouse developing gonads and discussed their presumptive functions on mouse gonadogenesis.  相似文献   
8.
The purpose of this investigation is to develop a better understanding of the structure-function relationship of the 2S fraction of soy protein that has not been considered in earnest by the research community. Defatted soy flour was used to extract the three major fractions of the protein (2S, 7S, and 11S). It was found that 2S exhibits better foaming and emulsification properties than the other two molecular fractions. Work was extended to structural properties, which were monitored using spectrophotometry, atomic force microscopy, scanning electron microscopy, small-deformation dynamic oscillation on shear, and large-deformation compression testing. An experimental protocol utilizing glucono-delta-lactone (GDL), GDL with N-ethylmaleimide, or GDL with urea was capable of identifying the nature of molecular interactions responsible for gelation. Surprisingly, it was found that in the initial stages of structure formation, 2S fared better than 7S, with 11S exhibiting the highest rates of aggregation. Given time, however, 7S produced a firmer network with a better water-holding capacity than that of 2S. Non-covalent interactions, as opposed to disulfide bridging, were found to be largely responsible for the changing functionality of the molecular fractions throughout the experimentation from the formation of a vestigial structure to that of a mature gel.  相似文献   
9.
The chemokine-mediated recruitment of effector T cells to sites of inflammation is a central feature of the immune response. The extent to which chemokine expression levels are limited by the intrinsic developmental characteristics of a tissue has remained unexplored. We show in mice that effector T cells cannot accumulate within the decidua, the specialized stromal tissue encapsulating the fetus and placenta. Impaired accumulation was in part attributable to the epigenetic silencing of key T cell-attracting inflammatory chemokine genes in decidual stromal cells, as evidenced by promoter accrual of repressive histone marks. These findings give insight into mechanisms of fetomaternal immune tolerance, as well as reveal the epigenetic modification of tissue stromal cells as a modality for limiting effector T cell trafficking.  相似文献   
10.
The objective of this study was to evaluate the effect of implanting an Antigen Release Devices (ARD) into dairy cows during the lactation cycle to induce an immune response. Subsequently, the concentrations of lactoferrin in serum and milk were measured. Forty healthy adult Chinese Holstein cows were divided into two equal groups: a test group and a control group. Animals in the test group received ARD implants, whereas the control group animals were not treated. An even spread across the two groups was maintained with animal selection based on parity, the lactation days and milk yields. The concentrations of lactoferrin in the serum and milk of all forty animals were measured using an Enzyme-Linked Immunosorbent Assay (ELISA). The results show that the implantation of an ARD did not significantly increase the concentration of lactoferrin in the serum and milk throughout the whole experiment period except on two occasions. The levels of lactoferrin in the milk and serum significantly increased on day 7 and on day 11 after implantation (p<0.05). There was a strong correlation between milk lactoferrin and serum lactoferrin (r=0.564, P<0.01). Three separate ARDs were used releasing its antigen load on day 0, 14 and 28 to induce a primary, secondary and tertiary response respectively. As the significant increases in the lactoferrin levels were only observed after the first ARD release, the effects of lactoferrin appears to be associated with the early phase of the immune response, consistent with its role in the host's innate defense system.  相似文献   
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