1-MCP处理对软枣猕猴桃果实品质及软化的影响

为探讨1-甲基环丙烯处理对软枣猕猴桃果实软化的影响,以软枣猕猴桃果实为试材,进行1-MCP处理,然后在常温下贮藏,检测与果实软化有关的防御生理指标。结果表明,1-MCP处理的软枣猕猴桃果实在常温贮藏条件下,明显延缓了可溶性固形物含量的上升和可滴定酸含量的下降,果实硬度下降速度明显延缓,从而延缓了果实的软化。同时,1-MCP处理推迟过氧化物酶和超氧化物歧化酶活性高峰的出现,且降低软枣猕猴桃果实在贮藏初期丙二醛(Malondialdehyde,简称MDA)含量,即1-MCP处理延缓软枣猕猴桃果实的软化。     

1-MCP处理对美味猕猴桃果实采后生理生化变化的影响

研究不同浓度、不同时间的1-MCP处理对"金魁"美味猕猴桃采后生理生化变化的影响。结果表明:不同浓度、不同时间的1-MCP处理均可延缓果实硬度的下降,抑制乙烯的合成,推迟乙烯高峰和呼吸跃变的到来,并降低其峰值,且能较好地保持Vc含量,抑制总糖及可溶性固型物的上升。同时,1-MCP处理还有效地缓解了果胶的降解,抑制淀粉酶和果胶酶的活性。在贮藏后期,1-MCP处理果实保持了较高的SOD活性,并延缓了CAT活性高峰的出现,从而达到延缓果实后熟衰老的目的。实验表明:运用浓度为1.5μL/L的1-MCP进行12 h处理对猕猴桃果实的贮藏保鲜有较好的效果;而经1-MCP二次处理的果实贮藏保鲜效果则更佳。     

1-甲基环丙烯和CO_2组合处理抑制柿果实脱涩软化的效应及其细胞壁成分的变化

为研究1-MCP(1-甲基环丙烯)对CO2脱涩柿果实软化及细胞壁成分变化的影响,探讨延长柿果实采后脱涩后货架期的方法,以‘磨盘柿’(Diospyros kaki Thunb cv.Mopan)为材料,研究了采用CO2、CO2+0.5μL/L1-MCP组合处理24h后,在室温下贮存对采后脱涩柿果实软化和细胞壁成分的影响。结果表明:CO2处理和CO2+0.5μL/L 1-MCP组合处理均能够有效的使涩柿脱涩,CO2+0.5μL/L 1-MCP组合处理相对于CO2处理来说在脱涩的同时能够有效的降低柿果实采后脱涩后柿果实贮存过程中硬度下降的速率,降低呼吸强度、乙烯释放量并且延迟呼吸高峰、乙烯高峰的出现时间,延缓柿果实水溶性果胶上升和共价性果胶下降的速率,以及半纤维素和纤维素含量下降的速率。因此,CO2+0.5μL/L 1-MCP组合处理可以延长柿果实采后脱涩后柿果实的货架期。     

乙烯和1-MCP对白姜花萜类香气及相关基因表达的影响

【目的】研究乙烯和1-MCP对白姜花萜类香气物质合成释放的影响,探究相关基因的表达变化。【方法】以白姜花Hedychium coronarium为材料,分别用10μL·L~(–1)的乙烯和4μL·L~(–1)的乙烯抑制剂1-MCP处理8 h,随后采用顶空固相微萃取和气相色谱–质谱(GC-MS)技术进行挥发性香气物质的测定,所得到的离子图用NIST 08数据库进行定性及定量分析。通过荧光定量PCR分析相关基因的表达情况。【结果】乙烯处理后白姜花香气成分罗勒烯、沉香醇、别罗勒烯、石竹烯和法尼烯的挥发量显著上升,相关香气萜类合成酶基因HcTPS1、HcTPS3和HcTPS10的表达量分别上升了116%、182%和63%;而用1-MCP处理后,罗勒烯、别罗勒烯和法尼烯的挥发量显著下降,HcTPS1、HcTPS3和HcTPS10基因的表达量分别降低了45%、30%和30%。乙烯处理后,核转录因子HcEIL1-1和HcEIL1-2的表达量分别上升了51%和114%;1-MCP处理后,HcEIL1-1和HcEIL1-2表达量分别下降了30%和60%。【结论】外源乙烯可以提升白姜花萜类花香物质的释放量,白姜花乙烯信号通路中的核转录因子HcEIL1-1和HcEIL1-2与萜类花香合成酶基因的表达模式一致。     

1-MCP在果蔬贮藏保鲜中的应用

1-甲基环丙烯（1-MCP）是一种新型的化学保鲜剂,通过抑制乙烯的产生、阻止乙烯作用的生理过程延缓果蔬的腐败和衰老,从而达到延长果蔬贮藏保鲜期的目的。通过对1-MCP的性质、果蔬贮藏保鲜的作用机理及影响1-MCP保鲜效果的因素进行综述,分析了卜MCP对果蔬采后生理和品质的影响,以及1-MCP在果蔬贮藏保鲜中的应用前景。     

冬枣酒软过程中呼吸强度和乙烯代谢的变化及1-MCP的处理效应

以半红果期的冬枣为材料 ,装入打孔的农膜袋中贮藏于 ( 2 0± 2 )℃和 ( 4± 0 5 )℃ ,研究其果实酒软的规律。结果表明 :随着贮藏时间的延长 ,果实乙醇含量持续上升 ,当乙醇含量达到 0 1%时 ,果实明显酒软 ;酒软过程中无呼吸高峰和乙烯释放高峰出现 ;果实的呼吸作用与乙醇积累呈正相关 ;降低温度可以抑制其呼吸强度 ,减缓酒软进程 ;室温下 1 0 0 μL·L-11 MCP密闭处理冬枣 12h ,明显抑制了乙烯释放量 ,但对呼吸作用的抑制效果不明显。冬枣贮藏期的酒软受呼吸代谢和乙烯代谢的双重调节 ,适宜的 1 MCP处理可以延缓酒软的发生     

山葡萄VaCBF1转录因子基因的克隆与表达分析

【目的】克隆山葡萄(Vitis amurensis)CBF1转录因子基因(VaCBF1),为其功能的深入研究及其在植物抗寒基因工程中的应用奠定基础。【方法】根据植物CBF基因AP2/EREBP保守区设计1对简并引物,利用PCR法从山葡萄cDNA中扩增VaCBF1基因的中间片段。再根据中间片段区域设计2对特异引物,采用反向PCR法扩增VaCBF1基因的5′端和3′端序列。将中间片段与5′端和3′端序列拼接后得到山葡萄VaCBF1基因的cDNA全长序列,据此设计1对特异引物,PCR扩增VaCBF1基因编码区的全长序列,并对其进行生物信息学分析。同时,利用荧光定量PCR分析山葡萄VaCBF1基因在不同逆境胁迫(干旱、低温、盐胁迫)下的表达情况。【结果】成功地从山葡萄中克隆得到VaCBF1基因cDNA全长序列,其长度为762bp,编码253个氨基酸,在GenBank注册号为DQ517296。同源性分析证实,VaCBF1属于CBF转录因子家族。荧光定量PCR分析发现,低温胁迫可以诱导山葡萄VaCBF1基因高表达,而该基因的表达不受盐及干旱处理诱导。【结论】首次从山葡萄中克隆了VaCBF1基因,并证实该基因参与了植物对低温胁迫的应答。     

Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons (Cucumis melo var. makuwa Makino)

Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation (EFF) and 1-methylcyclopropene (1-MCP) on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars (Yumeiren and Tianbao) during storage. The melons were stored in incubators with temperature of 15°C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities showed fluctuations in treated melons, while lipoxygenase (LOX) activity (P<0.01) and malondialdehyde (MDA) content (P<0.05) decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.     

高邮鸭群体MSTN、MyoD1和MyoG基因外显子中SNP位点的分析

MSTN、MyoD1和MyoG基因与禽类骨骼肌的生长发育密切相关。本试验以高邮鸭为素材,对MSTN、MyoD1和MyoG3个基因的外显子单核苷酸多态性(SNP)位点进行了鉴定,并对这些位点对蛋白质的影响及群体遗传信息进行了分析。结果显示,MSTN、MyoD1和MyoG3个基因的外显子分别有9个、4个和7个SNP位点,其中具有中度多态的位点分别为8个、1个和5个,有义突变各1个,这些有义突变均改变了相应蛋白质的理化性质以及二级结构。     

临草(麦)一号生物学特性及利用

临草(麦)一号是一种强冬性牧草作物,2000~2003年在山西省隰县、安泽县、浮山等多点试验,并在临汾市乔李镇和贺家庄大面积示范种植中,表现出良好的适应性和较高的生物产量,其鲜草总量平均达60000~75000kg/hm2,全期粗蛋白平均可达19%~27%。同时,介绍了临草(麦)一号的来源、生物学特性及优点,并结合山西的产业结构调整提出了发展饲草小麦的优势、可行性措施和对山西经济特别是农牧业发展的重要意义。     

小麦基础日粮添加酶制剂对断奶仔猪生长、代谢和血液IL-2水平的影响

在小麦基础日粮中添加酶制剂 ,研究其对断奶仔猪生长、代谢和血液IL 2水平的影响。试验将 4 8头杜洛克×大约克×二花脸三元杂交断奶仔猪分为玉米基础日粮组 (Ⅰ )、小麦基础日粮组 (Ⅱ )和小麦基础日粮添加 0 0 17% (质量分数 )酶制剂组 (Ⅲ )。预试期 4d ,正试期 2 8d。结果表明 ,Ⅰ组较Ⅱ组仔猪日增重提高 4 0 % (P>0 0 5 ) ;Ⅲ组较Ⅱ组仔猪日增重提高 7 6 % (P <0 0 5 ) ,但对仔猪饲料转化率无明显影响。Ⅰ组与Ⅱ组相比 ,仔猪血液尿素氮含量极显著降低 (P <0 0 1) ,T4含量显著升高 (P <0 0 5 ) ,其他指标变化不显著 ;而Ⅲ组较Ⅱ组仔猪血液尿素氮含量、T4和IL 2含量显著升高 (P <0 0 5 ) ,血糖和T3 含量有上升趋势 ,胰岛素 (Ins)含量却略有下降。结果提示 ,小麦日粮添加酶制剂可以显著提高仔猪增重 ,甚至超过玉米日粮 ;酶制剂可以通过影响仔猪代谢和免疫而促进仔猪生长     

The Effects of Dwarfing Genes （Rht-B1b,Rht-D1b,and Rht8） with Different Sensitivity to GA3 on the Coleoptile Length and Plant Height of Wheat

Understanding the effects of wheat dwarfing genes on the coleoptile length and plant height is crucial for the proper utilization of dwarfing genes in the improvement of wheat yield. Molecular marker analysis combined with pedigree information were used to classify wheat cultivars widely planted in major wheat growing regions in China into different categories based on the dwarfing genes they carried. The effects of the dwarfing genes with different sensitivity to gibberellins （GA3） on the coleoptile length and plant height were analyzed. Screening of 129 cultivars by molecular marker analysis revealed that 58 genotypes of wheat contained the dwarfing gene Rht-B1b, 24 genotypes of wheat contained Rht-D1b gene and 73 genotypes of wheat possessed Rht8 gene. In addition, among these 129 cultivars, 35 genotypes of wheat cultivars contained both Rht-B1b and Rht8 genes and 16 genotypes of wheat cultivars contained both Rht-D1b and Rht8 genes. Wheat cultivars with the dwarfing genes Rht-B1b or Rht-D1b were insensitive to GA3, while the cultivars with the dwarfing gene Rht8 were sensitive to GA3. Most of the wheat genotypes containing combination of Rht8 gene with either Rht-B1b or Rht-D1b gene were insensitive to GA3. The plant height was reduced by 24.6, 30.4, 28.2, and 32.2%, respectively, for the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b ＋ Rht8, and Rht-D1b ＋ Rht8 genes. The plant height was reduced by 14.3% for the wheat cultivar containing GA3-sensitive gene Rht8. The coleoptile length was shortened by 25.4, 31.3, 28.4 and 31.3%, respectively, in the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b ＋Rht8 and Rht-D1b ＋ Rht8 genes, while the coleoptile length was shortened only by 6.2% for the wheat cultivar containing Rht8 gene. We conclude that GA3-insensitive dwarfing genes （Rht-B1b and Rht-D1b） are not suitable for the wheat improvement in dryland because these two genes have effect on reducing both plant height and coleoptile length. In contrast, GA3- sensitive dwarfing gene （Rht8） is a relatively ideal candidate for the wheat improvement since it significantly reduces the plant height of wheat, but has less effect on the coleoptile length.     

Bt Cry1类毒素共性结构域的分析、表达及鉴定

【目的】分析定位Bt Cry1类毒素Cry1Ab、Cry1Ac、Cry1B、Cry1C、Cry1F的共性结构域,克隆并表达共性结构域蛋白,为筛选Bt毒素广谱抗体及建立广谱检测方法打下基础。【方法】利用生物信息学和分子模拟技术,通过SWISS-MODEL同源建模分别对5种Cry1类毒素进行三维建模,并结合Ramachandran plot、ERRAT和Verify3D方法评价模型构象的合理性。通过分析比对5种Cry1类毒素的三维结构,确定DomainⅠ区域作为5种Cry1毒素的共性结构域。以含Cry1Ac基因的苏云金芽孢杆菌库斯塔克亚种为模板设计引物,PCR扩增获得共性结构域DomainⅠ基因,将其经NcoⅠ和NotⅠ双酶切连接至原核表达载体pET-26b(+),构建原核表达载体pET-26b-DomainⅠ。重组质粒经菌液PCR、双酶切以及测序鉴定验证正确后,转化至E.coli BL21(DE3),经终浓度为1 mmol·L~(-1)的IPTG在20℃下诱导表达16h后检测共性结构域蛋白的表达情况。离心收集诱导表达的大肠杆菌菌液,进行超声波破碎处理,收集上清及沉淀,采用SDS-PAGE分析融合蛋白的表达。利用His-Trap HP镍亲和柱纯化上清中的可溶性融合蛋白,经SDS-PAGE电泳、Western blot和ELISA试验验证纯化的共性结构域蛋白的生物活性。【结果】基于氨基酸序列及三维空间比对分析,发现5种Cry1类毒素的DomainⅠ的序列一致性最高,而且它们的DomainⅠ三维结构几乎完全重合,确定DomainⅠ区域作为5种Cry1毒素的共性结构域,通过PCR、双酶切及测序鉴定成功构建原核表达载体pET-26b-DomainⅠ,经IPTG诱导表达、His-Trap HP镍亲和柱纯化获得了可溶性的DomainⅠ共性结构域蛋白,SDS-PAGE和Western blot证实表达的共性结构域蛋白的分子量约为33.4 kD,且能与抗His标签鼠单克隆抗体发生特异性反应,ELISA试验证实共性结构域蛋白与5种Cry1类毒素特异性抗体均具有很强的结合能力,抗原表位分析结果显示共性结构域蛋白具有和完整的Cry蛋白存在多个潜在抗原表位位点的特征,抗原表位区域所占的比例分别为48.4%和63.6%,表明共性结构域蛋白具有良好的免疫原性和免疫反应性。【结论】基于分子模拟与分子克隆技术,成功定位及表达纯化获得共性结构域蛋白,为下一步利用共性结构域为靶标分子制备广谱特异性识别Cry1类毒素抗体打下基础。     

攀西地区不同播种期·播种量和施肥量对大麦生长发育及产量的影响

[目的]研究攀西地区不同播种期、播种量和施肥量对西昌学院新育成的西大麦1号(Hordeum agriocrithon)生长发育和产量的影响,为该地区大麦高产栽培提供指导,并为其进一步推广提供科学依据。[方法]试验设不同播种期和播种量试验及不同氮、磷肥施用量试验。[结果]在攀西地区,西大麦1号以10月25日左右播种,播种量150 kg/hm2,施纯N量108 kg/hm2,施P2O5量113 kg/hm2,施K2O量90 kg/hm2(N∶P2O5∶K2O为1.20∶1.26∶1.00)组合效果较好。播种密度越大越易感染白粉病和叶锈病,多施或偏施尿素会导致大麦抗病性和抗逆性下降,越易感染白粉病和叶锈病;肥料处理间氮肥的施用量增加,生育期延长,但磷肥施用量对生育期影响不明显。[结论]在攀西地区,西大麦1号的适宜播期为10月25日左右,适宜播种量为150 kg/hm2,适宜的N、P2O5、K2O施用量分别为108、113、90,N∶P2O5∶K2O为1.20∶1.26∶1.00。     

Lethal and Sub-Lethal Effects of Transgenic Rice Containing cry1Ac and CpTI Genes on the Pink Stem Borer,Sesamia inferens（Walker）

Lethal and sub-lethal effects of transgenic rice containing crylAc and CpTI genes on the pink stem borer, Sesamia inferens,were studied to collect information for ecological risk assessment on insect-resistance of transgenic rice. In vitro insectfeeding bioassays were conducted to evaluate the lethal and sub-lethal effects oftransgenic flee lines (Ⅱ YouKF6 and KF6)containing crylAc+CpTI genes on S. inferens at four different growth stages, viz., seedling, tillering and elongation, booting,and milk and maturing. Transgenie rice at seedling stage showed significantly high lethal effect on S. inferens with the shortest lethal duration for 50 and 100% individuals and the highest corrected mortalities after feeding on transgenic lines at this stage for 3 and 6 d. Followed by tillering and elongation stage, 50 and 100% S. inferens were dead after feeding on transgenic lines at this stage for 4 and 10 d, respectively. Moreover, corrected mortalities for 6 d feeding on transgenic lines at this stage were significantly higher than that at booting, and milk and maturing stages. Lethal effect of KF6 on S. inferens decreased significantly at booting stage. Lethal duration for 50% S. inferens significantly extended and its corrected mortalities for 6 d feeding also declined remarkably. However, lethal effect of Ⅱ YouKF6 on S. inferens did not decrease significantly at this stage. Transgenic rice at booting, and milk and maturing stages did not show significant lethal effect to S. inferens and it showed the longest lethal duration for 50% individuals and the lowest corrected mortalities for 3 and 6 d feeding. A few larvae of S. inferens could survive, pupate and emerge on these two transgenic lines at booting, and milk and maturing stages. Sub-lethal effect of two transgenie lines on S. inferens also differed significantly between different developmental stages. Continuously feeding on transgenic rice lines at seedling, and tillering and elongation stages delayed the development of larvae and pupae and decreased pupation rate, but no effect was observed on eclosion rate. Larval development was significantly inhibited after feeding on transgenic rice at booting stage, but no obvious effect was observed in pupal stage, pupation and eclosion rate. There were no significant differences for larval and pupal development, pupation,and eclosion rates between feeding on transgenic and control rice lines at milk and maturing stage. Larval and pupal weights significantly declined, but no influence was observed on fecundity when S. inferens infested on transgenic rice at any stage.These showed that there were significant differences in lethal and sub-lethal effects of transgenic rice on S. inferens among developmental stages, and the effects gradually decreased with the increase of growth stages of rice plant.     

L-蛋氨酸强化卤虫对鳙开口苗生长、氨基酸组成及相关酶活性的影响

【目的】研究L-蛋氨酸强化卤虫无节幼体对鳙开口苗生长、氨基酸组成及肌酸激酶、γ-谷氨酰转移酶、Na~+K~+-ATP酶活性的影响,为鳙开口苗的培育提供参考。【方法】用0(对照),400,800,1 600mg/L的L-蛋氨酸强化初孵卤虫无节幼体(Artemia nauplii)16h,投喂鳙(Aristichthys nobilis)开口苗21d,分别于试验第7,14和21天取样测定鳙开口苗的体长和体质量,第21天取样测定开口苗体内氨基酸组成和相关酶活性。【结果】试验第7和14天,L-蛋氨酸对各处理组鳙开口苗的特定增长率(SGR)和体长日增长率(BLGR)无显著影响(P0.05);在试验第21天,400和800mg/L L-蛋氨酸处理组鳙开口苗的SGR、BLGR显著高于0和1 600 mg/L L-蛋氨酸组(P0.05)。L-蛋氨酸能显著提高各处理组卤虫无节幼体和鳙开口苗体内的蛋氨酸含量,且各处理组之间蛋氨酸含量差异显著(P0.05);800mg/L L-蛋氨酸处理组鳙开口苗总氨基酸含量显著高于0和1 600mg/L组(P0.05);400和800mg/L L-蛋氨酸组鳙开口苗赖氨酸(Lys)、精氨酸(Arg)和半胱氨酸(Cys)的含量显著高于0和1 600mg/L L-蛋氨酸组;800mg/L L-蛋氨酸组鳙开口苗甘氨酸(Gly)和丙氨酸(Ala)的含量显著高于0和400 mg/L L-蛋氨酸组(P0.05);800mg/L L-蛋氨酸组鳙开口苗苏氨酸(Thr)含量显著高于其他3组(P0.05);800mg/L L-蛋氨酸组鳙开口苗的苯丙氨酸(Phe)含量显著高于对照组(P0.05)。800mg/L L-蛋氨酸组鳙开口苗肌酸激酶、γ-谷氨酰转移酶活性显著高于其他3组(P0.05);400和800mg/L L-蛋氨酸组鳙开口苗的Na+K+-ATP酶活性显著高于0和1 600mg/L L-蛋氨酸组(P0.05)。【结论】在本试验条件下,800mg/L L-蛋氨酸强化的卤虫无节幼虫能有效改善鳙开口苗体内的氨基酸组成和相关酶活性,进而提高其生长性能。     

小美旱杨插条苗(1-0)施肥的研究

通过田间试验,对小美旱杨1年生插条苗施用N,P,K矿质肥料的效果及其生长规律进行了研究。结果表明:华北地区的黄潮土所含N,P元素不能满足苗木生长的需要,而含K丰富。培育小美旱杨1年生插条苗需施用N和P肥,K肥可以不施。最佳施肥量为:N200kg/ha,P_2O_6100kg/ha;其N,P,K比例为2∶1∶0。根据当前的肥料和苗木的市价,用反应曲面方程计算获得最大经济效益的施肥量为N273.93kg/ha,P_2O_6121.15kg/ha。