硬枝碱蓬种子萌发对盐旱胁迫的响应

以硬枝碱蓬种子为试材,在最适的温光条件下,研究不同NaCl和PEG(分子量为6 000)处理对硬枝碱蓬种子萌发特性的影响。结果表明:低浓度的盐(NaCl浓度为100mmol/L)显著缩短了硬枝碱蓬种子的萌发进程,但对硬枝碱蓬种子的最终萌发率无显著影响;中等或高浓度的盐(NaCl浓度为200~500mmol/L)显著延长了硬枝碱蓬种子的平均萌发时间,降低了种子的最终萌发率。轻度干旱(外界渗透势为-0.2MPa时)显著促进硬枝碱蓬种子萌发,缩短平均萌发时间,快速达到最终萌发率,完成萌发进程,最终萌发率最高,为99%,显著高于对照;中度和严重干旱(渗透势在-1.2~-0.4MPa范围时)显著抑制硬枝碱蓬种子萌发,随着外界渗透势的降低,种子最终萌发率呈显著下降的趋势,平均萌发时间延长,达到最终萌发率的速度较慢,完成萌发进程用时延长;在外界渗透势为-1.2MPa时最终萌发率最低,仅为28%。硬枝碱蓬种子的耐盐(NaCl)阈值和极限值分别为394.30mmol/L和894.30mmol/L;硬枝碱蓬种子的耐旱(PEG-6000)阈值和极限值分别为-0.88MPa和-1.79MPa。综上所述,硬枝碱蓬种子萌发时表现出较强的抗盐性和抗旱性。     

碱胁迫对碱蓬种子萌发的影响

采用不同浓度的Na2CO3和NaHCO3溶液处理土壤,研究碱性盐对碱蓬种子萌发及幼苗生长状况的影响。结果表明:随着碱性盐浓度的升高,碱蓬种子的成苗率、发芽指数和幼苗生物量均有不同程度降低,在Na+浓度相同的情况下,Na2CO3对碱蓬种子萌发及幼苗生长的抑制作用大于NaHCO3;碱性盐对碱蓬幼苗地下部分胁迫作用大于地上部分胁迫作用;可以将碱蓬引种到Na2CO3浓度小于50mmol/L和NaHCO3浓度小于100mmol/L的盐碱地。     

地木耳提取物对盐碱条件下孔雀草种子萌发的影响

探讨地木耳提取物对盐胁迫下孔雀草种子萌发的影响。用不同浓度NaCl盐溶液处理孔雀草种子,筛选盐害浓度,在用不同浓度地木耳提取液处理盐胁迫下孔雀草种子,记录种子萌发率。结果表明,低盐溶液对孔雀草种子萌发无显著影响,超过0.2mol/LNaCl溶液开始产生盐害影响,以0.8mol/L盐害最重;高盐溶液处理下,地木耳提取物有显著缓解盐害效应,以5mg/L效果最好。     

几种处理对两种白头翁种子萌发的影响

以白头翁和兴安白头翁种子为试材,研究了植物生长激素、温度、光照和浸种等处理方法对2种白头翁种子萌发的影响.结果表明:5 mg/L NAA和100 mg/L GA3处理的白头翁种子萌发率显著高于对照(P＜0.05);10和50 mg/L GA处理的兴安白头翁其发芽率和发芽势均显著高于对照(P＜0.05).2种白头翁种子的萌发率和发芽势均随着温度的升高而明显增高,适宜的发芽温度为25～30℃.延长光照和浸种时间处理可以明显促进2种白头翁种子的萌发率和发芽势.     

光照、温度等因子对卷丹百合种子萌发特性的影响

研究了光照、温度、pH值和浸种温度等因子对卷丹百合种子萌发的影响。结果表明:卷丹百合种子为需光种子,在光下萌发,在黑暗中萌发受抑制;卷丹百合性喜温暖,种子萌发的适宜温度以20℃为宜;在pH 6.0时种子的萌发率最高;在播种前对卷丹百合进行温汤浸种可以促进种子萌发,浸种的适宜温度以35～45℃为宜。     

环境因素对曼陀罗种子萌发特性的影响

研究了光照、温度、pH以及浸种温度对曼陀罗种子萌发率的影响。结果表明:曼陀罗种子为嫌光种子;种子在温度21～27℃,pH 4～8的范围内都有较高的萌发率;使用40～60℃的温水对曼陀罗种子浸种,萌发率显著提高。     

丁香酸对苦瓜种子萌发、幼苗生长的影响

研究了不同浓度丁香酸对苦瓜种子发芽及幼苗生长的影响.结果表明:随着丁香酸浓度的增大,苦瓜种子萌发率有所降低,并且与对照相比,各处理均达到了显著性差异水平(10-7 mol/L浓度除外).同时,随着丁香酸浓度的增大,苦瓜幼苗的生长也显著受到抑制.     

苯甲酸对豇豆种子萌发及抗氧化酶活性的影响

研究了不同浓度的苯甲酸对豇豆种子发芽、幼苗生长及抗氧化酶活性的影响。结果表明:随着苯甲酸浓度的增大,豇豆种子萌发率及豌豆幼苗的根长和苗长均呈降低的趋势。与对照相比,豇豆种子萌发率和豇豆幼苗的苗长均在苯甲酸浓度达到最大时受到显著抑制,而豇豆幼苗的根长在苯甲酸浓度最低时就受到显著抑制;随着苯甲酸浓度的增大,豇豆种子的抗氧化酶活性(SOD和POD)均呈降低趋势。10-5mol/L和10-6mol/L分别显著抑制了豇豆种子SOD和POD活性。     

光照和温度等因素对苘麻种子萌发特性的影响

以苘麻种子为试材,研究了光照、温度、pH以及浸种温度对苘麻种子萌发率的影响。结果表明:苘麻种子为需光种子,温度15～30℃、pH 4～8的条件下萌发率较高;使用30～60℃的温水对苘麻种子浸种,萌发率均显著高于对照。     

Na_2CO_3胁迫对波斯菊种子萌发的影响

以波斯菊种子为试材,研究了不同浓度的Na2CO3胁迫对种子萌发特性的影响。结果表明:随着盐浓度的升高,波斯菊种子的初始萌发时间、萌发高峰期均随之延迟,发芽率、发芽势、发芽指数和活力指数均呈先升高后下降的变化趋势;低浓度(≤5mmol/L)Na2CO3盐溶液对种子的发芽率、发芽势、发芽指数、活力指数均有一定的促进作用,而高浓度(>5 mmol/L)盐溶液则对波斯菊种子的萌发有明显的抑制作用。     

氮磷钾硼肥配施对青花菜养分吸收分配及产量和品质的影响

研究了不施肥处理,氮磷钾配施和增施硼肥对青花菜养分吸收分配及产量和品质的影响。结果表明,现蕾期至花球膨大期,青花菜对氮、磷、钾的吸收量最大,整个生长期对钾的吸收最多,氮次之,磷最少。氮磷钾主要分配在叶片中,现蕾后逐渐向花球转移,从现蕾到采收时,叶片中氮、磷、钾分配率分别降低了19.6%、10%和9.0%,花球中氮磷钾分配率分别提高了23.1%、15.9%和11.1%。不施氮、磷、钾肥显著降低了花球产量、维生素C含量和成品率,增施硼肥处理的花球成品率较氮磷钾肥处理提高了4.8%,不施氮肥和钾硫肥(K₂SO₄)显著降低了花球中的硫代葡萄糖苷含量。相关性分析表明,青花菜产量与植株内氮、钾积累量显著正相关,成品率与植株内磷营养显著正相关。     

江汉平原麦瓜棉菜一年四熟栽培技术

江汉平原是国家优质粮食、优质棉花和双低油菜重要生产基地,也是湖北省西瓜主产区。种植西瓜对增加农民收入、丰富市场、发展农村经济、提高土地利用率具有重要作用。江汉平原西瓜生产的突出特点是间作套种,早在20世纪70年代就推广了“麦／／瓜-稻”这种水旱、粮经作物配套种植的优化模式．并获得原荆州地区科技进步二等奖。由于西瓜间作套种提高了单位面积的经济效益、     

Up-regulation of mRNA expressions of fas,bcl-2, bim,bax, caspase-3, caspase-9, and bcl2l12 in K562 treated with bortezomib

AIM: To detect the treatment of K562 leukemia cells with bortezomib altering the expression of genes fas, bcl-2, bcl2l12, bim, bax, caspase-9 and caspase-3.METHODS: MTT assay was used to detect the inhibition of proliferation. Apoptosis was detected by Annexin-V staining and mitochondrial transmembrane potential (Δψm). RT-PCR was used to analyze the mRNA expressions of fas, bcl-2, bcl2l12, bim, bax, caspase-3 and caspase-9.RESULTS: Bortezomib caused a time- and dose-dependent inhibition of cell proliferation and IC50 of 24 h and 48 h were 161.41 nmol/L and 96.33 nmol/L, respectively. At the concentration of 104 nmol/L, bortezomib induced apoptosis in a time-dependent manner, including increasing annexin-V positivity and decreasing the Δψm. RT-PCR showed that bortezomib up-regulated the mRNA expression of fas, bcl2l12, caspase-9 and caspase-3, but mRNA expressions of bcl-2, bim and bax did not changed obviously.CONCLUSION: Bortezomib inhibits the proliferation of K562 and induces apoptosis, in which fas, bcl2l12, caspase-9 or caspase-3 gene is one of the main genes taking part in.     

Comparison of yield,fruit quality,antioxidant activity,and some phenolic compounds of white seedless grape obtained from organic,conventional, and integrated fertilization

The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds.     

Climatic, landform, microtopographic, and overstory canopy controls of tree invasion in a subalpine meadow landscape, Oregon Cascades, USA

Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors at multiple spatial scales. The purpose of this research was to quantify spatiotemporal patterns of meadow invasion; and how climate, larger landforms, topography, and overstory trees have interactively influenced tree invasion. We combined airborne Light Detection and Ranging (LiDAR) characterizations of landforms, topography, and overstory vegetation with historical climate, field measurements of snow depth, tree abundance, and tree ages to reconstruct spatial and temporal patterns of tree invasion over five decades in a subalpine meadow complex in the Oregon Cascade Range, USA. Proportion of meadow occupied by trees increased from 8?% in 1950 to 35?% in 2007. Larger landforms, topography, and tree canopies interactively mediated regional climatic controls of tree invasion by modifying depth and persistence of snow pack, while tree canopies also influenced seed source availability. Landscape context played an important role mediating snow depth and tree invasion; on glacial landforms tree invasion was negatively associated with spring snowfall, but on debris flows tree invasion was not associated with snow fall. The importance of snow, uncertain climate change impacts on snow, and mediation of snow by interacting and context dependent factors in complex mountain terrain poses substantial hurdles for understanding how these ecotones may respond to future climate conditions.     

中国''''99昆明世界园艺博览会蔬菜瓜果园

蔬菜瓜果园作为中国’99昆明世界园艺博览会六大专题展园之一 ,占地 4 90 0ｍ2 。园内以农舍草屋为中心 ,通过瓜架、篱笆、草亭及蔬菜瓜果栽培 ,构出一幅农家乐园式的田园风光。另外 ,通过集中展示中国蔬菜瓜果的科技生产水平 ,丰富的资源优势 ,色彩缤纷、新奇别致的蔬菜瓜果品种 ,来突出本次世博会的主题“人与自然 ,和谐发展———迈向 2 1世纪” ,从而展现“蔬菜瓜果园艺是人类赖以生存的重要食源和艺术”为主题思想的蔬菜瓜果园内涵。　　蔬菜瓜果园位于世博园主入口世博大道南侧 ,与盆景园、药草园相邻。在总体布局、栽培上充分运用园…     

Some responses of cucumber,grown in beds of peat,to N,K and Mg

Two levels of N and four levels of K, applied to beds of sphagnum peat before planting (Experiment A), were tested in factorial combination with three concentrations of N (50, 175 and 300 mg 1^-1) and two of K (50 and 250 mg T1) in the liquid feed. In three cucumber crops grown, Mg was supplied or omitted before planting as a split plot factor (96 subplots). In two further crops (Experiment B), grown in fresh peat, six concentrations of N (20-320 mg 1^-1) were tested in the liquid feed, all other nutrient levels being constant. In Experiment A, the early yield was reduced by low and high levels of N. The main effect of N on the final yield was not significant, but maximum yield was achieved with 175-300 mg 1^-1 N in the liquid feed where the peat received a small amount of ureaformaldehyde (15 g m“2) and Mg fertilizer. The N x Mg interaction became increasingly marked with successive crops; the loss in yield due to Mg deficiency (<31%) increased with the amount of N applied. K deficiency reduced the yield by up to 66%, and very high levels of K also tended to decrease the yield. The K x Mg interaction became more marked with time and the loss in yield due to Mg deficiency (<23%) increased with the amount of K applied. Leaves from N, K and Mg deficient plants contained <2.5% N, <1.0% K and <0.28% Mg respectively. In Experiment B, where N was supplied only in the liquid feed, the highest yield was obtained at 220 mg 1^-1. The relation between yield and the total amount of N supplied in the feed was defined by a quadratic regression.     

盆景果树的发展、特点及价值

盆景果树集"艺术欣赏与果实享用"于一身。文章重点阐述盆景果树的定义、发展史与现状、分类与特点、文化和经济的双重价值等内容。     

早熟优质迷你西瓜品种玲珑王的选育

玲珑王是杂交一代西瓜新品种,早熟,全生育期100 d,果实发育期28 d.植株长势中强,低温弱光条件下坐果性好,果实商品率较高.果实椭圆形,果彤指数1.28.果皮绿底覆深绿色窄条带,皮厚约5 mm,果肉鲜红色,中心折光糖含量11.7%,肉质细脆,汁多纤维少,口感风味好.抗病性、抗逆性较强.单瓜质量1.5 kg,1 hm2产量达到33 000～58 500 kg.