Salinity and Temperature Effects on Seed Germination of Milk Thistle

Abstract

Milk thistle [Silybum marianum (L.) Gaertn] is an annual plant belonging to the Asteraceae family whose ripe seeds contain flavonoid substances, which are important in the modern pharmaceutical industry. Seed germination is a major factor limiting the establishment of plants under saline conditions. The effect of salinity and temperatures on germination and seedling establishment was studied in two genotypes of milk thistle, an Iranian wild type and German (Royston) type in the laboratory and in the field. Experiments were done with seven salt concentrations [0.1 (control), 1, 3, 6, 9, 12, and 15 dS/m] and three temperatures (15, 25, and 35°C). There were three replications for each treatment, and the experiment was run three times. The results showed that the percentage of germination and the number of normal seedlings at different salt treatment at 15°C were higher than at 25 or 35°C. The mean time to 50% germination was least at this temperature for both genotypes. Results suggested all germination indices and seedling emergence (50%) were achieved at levels up to 9 dS/m salinity at 15°C. Also, seeds at a salinity of 9–15 dS/m will germinate and up to 25% of the control nonstress treatment could emerge at the low temperature of 15°C.     

不同葡萄品种膜质过氧化和保护酶活性对盐胁迫的响应

研究了不同浓度NaCl处理对双丰、左山二、贝达以及金玫瑰细胞膜透性、膜质过氧化和保护酶活性的影响。结果表明:不同处理间,4个品种耐NaCl胁迫的动态响应表现出显著差异。随胁迫浓度的增大和胁迫时间的延长,MDA含量和细胞膜透性表现出增高趋势,增高幅度由高到低的顺序为双丰、左山二、贝达、金玫瑰;保护酶SOD活性整体表现出先增后降趋势,金玫瑰和贝达升高幅度相对较大;POD活性整体表现出下降趋势,但金玫瑰和贝达下降幅度相对较小。     

复盐胁迫对几种燕麦种子萌发指数的影响

采用加拿大7种燕麦(A.nuda)种子,在不同梯度的Na2SO4、NaCl等组分盐溶液中进行发芽试验.结果表明:复盐胁迫下,种子开始发芽的时间推迟,发芽过程延长,随着盐胁迫浓度的增加,7种燕麦种子的发芽率、发芽势和发芽指数、简易活力指数均有不同程度的降低,而盐害指数升高,且不同品种间存在显著或极显著差异；随复盐浓度的增...     

禾本科牧草K~+/Na~+与其耐盐性的关系

耐盐牧草有选择性吸收Ｋ＋的能力，通过比较在相同盐份中生长的不同牧草种的叶片Ｋ＋／Ｎａ＋，可鉴定出种间耐盐性，Ｋ＋／Ｎａ＋值大的材料耐盐性强。     

福建柏抗盐无性系初步选择研究

对福建柏1年生无性苗木用100 mmol.L-1NaCl进行胁迫处理,在处理60 d后对苗木的叶绿素、脯氨酸、可溶性糖、丙二醛等指标进行测定,结果表明:参试的福建柏无性材料间叶绿素含量、可溶性糖含量、丙二醛含量、脯氨酸含量等指标存在明显差异,且受遗传力制约,这些指标可作为抗盐无性系选育的依据;盐胁迫下309、327、328、381-2无性系的叶绿素、脯氨酸、可溶性糖含量分别比总体平均值增加了6.8%～57.1%、11.7%～17.3%、0.7%～14.5%,丙二醛含量减少了17.8%～56.8%。说明这4个无性系有相对较高的抗盐性,初步筛选出309、327、328、381-2抗盐无性系。     

Salt Separation Processes in the Saltcedar Tamarix ramosissima (Ledeb.)

Salt cedars (Tamarix) are invasive halophytic species and heavy water consumers. However, Tamarix possesses interesting characteristics accounting for its opportunistic and resilient abilities: analogous to a miniature photodesalinization machine, it thrives on saline soils toxic to most plants. Here we observe, document, and reveal the salt separation process of T. ramosissima. Specimens were cultivated under controlled artificial conditions, then analyzed by microscopic and spectroscopic techniques. Tamarix ramosissima is shown to produce varied morphologies of salt crystal aggregates from vesiculated trichomes and possess the ability to separate anions and cations. Sodium chloride, potassium chloride (KCl), and potassium sodium sulfate [K_2.25Na_1.75(SO₄)₂] were major exuded salt crystal phases, with smaller quantities of other phases present. Compositions of crystals exuded by individual plants were consistent with compositions of the soils they grew on. Although T. ramosissima may be an invasive nuisance, it may possess other worthwhile attributes such as the potential to be a viable phytoremediator and environmental indicator.     

Population Studies of Limonium stocksii (Plumbaginacea) from a Salt Desert Near the Arabian Sea Coast

Abstract

A population of Limonium stocksii was studied for one year at the upper end of Manora Creek along the Arabian Sea coast, near Karachi, Pakistan. The community was divided into three zones. Soil pH varied from 8.1 to 8.5. Soil conductivity was highest (191 dS m^?1) in September and lowest (55 dS m^?1) in June. Soil water content was relatively low and varied from 1.6% in February to 9.5% in June. Limonium stocksii maintained a persistent seed bank, which peaked at 5,887 seeds m^?2 in May. Very slow growth was observed; however, plants in the intermediate zone showed better growth than the other two zones. Stem and leaf tissue water content were affected by salinity fluctuations, but root tissue water remained unaffected. Sodium (Na⁺) and chloride (Cl^?) accumulated in stems and leaves more than other ions. Leaves also accumulated a very high amount of magnesium (Mg⁺⁺) compared to roots and stems.     

天津外环线主要树种枝条枯死原因分析

2007年秋季对天津外环线树木枯枝情况进行了调查分析,发现天津市外环线树木枯枝现象比较普遍,平均枯枝率达29.01%。枯枝最严重的是柳树,其次是白蜡、毛白杨等。外环线外侧树枝的枯死程度明显比内侧树的严重。树龄的大小不是决定树木枯枝的主要因素,环境的影响是决定因素之一,其中地表水的含盐量和含钠量与树木的枯枝程度有密切关系。     

中国对虾不同生长阶段对蛋白质,脂肪,糖类和无机盐的需求

设计不同蛋白质，脂肪，无机盐，糖类配比的９个配方饵料，对中国对虾前，中，后３个生长阶段进行了饲喂试验。结果：各营养要素影响对虾增重的顺序第生阶段为脂肪〉蛋白质〉无机盐〉糖类，最适量为７％，４０％，１３％，２０％；第二阶段为蛋白质〉脂肪〉糖类〉无机盐，阳适量为４５％，５％，２３％，１３％；     

QuEChERS-超高效液相色谱-质谱联用法测定熊胆粉中9种苯二氮䓬类药物残留量

建立了超高效液相色谱-质谱联用法(UPLC-MS/MS)快速测定中药材熊胆粉中9种苯二氮?类药物残留的方法。样品以乙腈为提取溶剂,经萃取盐包除杂提取,采用分散式固相萃取管 (EMR-Lipid dSPE) 净化,ACQUITY BEH C18色谱柱(1.7 μm,2.1×100 mm)分离,多反应监测模式(MRM)采集数据,外标法定量。在优化的条件下,虽9种药物存在不同程度的基质效应,但不影响检测结果的准确性。方法学考察结果显示,9种苯二氮?类药物在对应的浓度范围内线性关系良好,决定系数(R²)≥0.9961,方法检出限(LOD,S/N =3)在0.06～0.71 μg/kg范围内,定量限(LOQ,S/N =10)在0.20～2.60 μg/kg范围内,3个加标水平的平均回收率在69.1%～108.0%范围内,日内RSD为1.8%～9.0%,日间RSD为2.6%～9.3%。该方法前处理操作简便、重现性好,准确度高,为熊胆粉中苯二氮?类药物残留的风险监控提供了一种有效的检测技术。