Agar/galactomannan gels applied to shoot regeneration from tobacco leaves

This study concerns the efficacy of partial agar substitution by galactomannans as support in plant regeneration media for Nicotiana tabacum. The production of multiple shoots from leaf-derived callus and their rooting were evaluated. The galactomannans applied were obtained from Cassia fastuosa (cassia) and Cyamopsis tetragonolobus (guar gum — a commercial galactomannan) seeds. The results obtained on media solidified with mixtures of agar/galactomannan (3 g dm⁻³ each) gels were compared with those on media gelled with a standard concentration of agar (6 g dm⁻³). The in vitro performance allowed to conclude that the use of galactomannans raised the number of shoots and improved their quality. Furthermore, the length of roots and the size of leaves were significantly higher in the media solidified with agar/guar galactomannan mixtures.     

水杨酸调节决明根系铝诱导的氧化胁迫

水杨酸(Salicylic acid,SA)在调节生物和非生物胁迫,诱导植物氧化胁迫中起着重要的作用,但对铝诱导的氧化胁迫的调节作用尚不清楚.本文研究了SA对决明(Cassiatora L.)根系铝诱导的H2O2和O2-含量变化,包括抗氧化酶活性以及细胞质膜过氧化胁迫变化的影响.介质中20 μmol/L铝处理增加质膜透性,导致MDA含量上升及根尖细胞Evans blue染色加重(测定细胞死亡),而外源供给5 μmol/L SA能缓解铝诱导的氧化胁迫.SA处理能明显降低根尖H2O2和O2-的含量,但两者含量与CAT、APX和GR的活性变化没有相关性,而与POD活性增加有关.水杨酸诱导H2O2含量的下降与抑制O2积累和SOD活性有关.结果表明,SA可能激活一条由H2O2介导的、依赖于POD的抗氧化机制来缓解脂质的过氧化作用.     

Cytogenetics and chromosome banding patterns in Caesalpinioideae and Papilionioideae species of Pará, Amazonas, Brazil

Despite the abundance of woody legumes in Brazilian Amazonian rain forests, there are few chromosome counts on the native species of this important region. The present work presents such data for 13 species of Caesalpinioideae (the genera Bauhinia , Caesalpinia , Cassia , Chamaecrista and Senna ) and Papilionioideae ( Bowdichia , Centrosema and Dioclea ) collected from 17 natural populations. Our report represents the first chromosome counts for the genera Bowdichia and Dioclea and for four of the studied species. Observations are made on chromosome morphology, size, condensing behaviour and interphase nucleus structure. Banding with fluorochromes carried out for the first time in Caesalpinioideae revealed discrete CMA⁺/DAPI^– terminal (GC-rich) bands on 2–4 chromosome pairs of most species analysed, with a few species presenting discrete CMA^–/DAPI⁺ (AT-rich) bands. Significant differences in chromosome size, morphology and condensing behaviour were observed among members of the controversial tribe Cassieae ( Cassia , Chamaecrista and Senna ), revealing the tribe to be a heterogeneous group from the karyological point of view.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 181–191.     

水杨酸调节决明根系铝诱导的氧化胁迫

水杨酸(Salicylicacid,SA)在调节生物和非生物胁迫,诱导植物氧化胁迫中起着重要的作用,但对铝诱导的氧化胁迫的调节作用尚不清楚。本文研究了SA对决明(CassiatoraL.)根系铝诱导的H2O2和O2-含量变化,包括抗氧化酶活性以及细胞质膜过氧化胁迫变化的影响。介质中20mmol/L铝处理增加质膜透性,导致MDA含量上升及根尖细胞Evansblue染色加重(测定细胞死亡),而外源供给5mmol/LSA能缓解铝诱导的氧化胁迫。SA处理能明显降低根尖H2O2和O2-的含量,但两者含量与CAT、APX和GR的活性变化没有相关性,而与POD活性增加有关。水杨酸诱导H2O2含量的下降与抑制O2-积累和SOD活性有关。结果表明,SA可能激活一条由H2O2介导的、依赖于POD的抗氧化机制来缓解脂质的过氧化作用。     

茜草、虎杖及决明子的高速逆流色谱研究

以茜草、虎杖及决明子三种传统中药材为原料,利用高速逆流色谱对其蒽醌类活性成分进行制备性分离研究.研究表明氯仿甲醇水=4x2(x=3.5～4.0)作为溶剂分离系统,对含蒽醌类中草药的乙醇初提物进行分离,具有通用性.对制备物进行薄层色谱分析,检验被分离的蒽醌类成分,进一步证实了该方法的有效性及实用性.     

毛决明种子不同发育时期发芽力和脱水耐性的初步研究

毛决明种子发芽力在花后39d后逐渐上升,发芽率和发芽指数在花后53d,活力指数在花的67d最大值,而后有所降低,花后39-74d,含水量逐渐下降,但下降速度不等,花后67d种子干重达到最大值,花后67-74d含水量显著下降,花后39-74d,含水量逐渐下降,但下降速度不等,花后67d种子干重达到最大值,花后67-74d含水量显著下降。种子存在明显的成熟脱水阶段。种子的脱水耐性在花后46-60d逐渐增强,60d达到最大值,后有所下降,轻微脱水可显著提高花后46d和67d的种子的发芽率,花后60-67d的种子能忍耐10%含水量,毛决明种子极可能是正常性种子。     

柱隔孢属二新种*

柱隔孢属二新种:决明柱隔孢Ramularia cassiae,寄生在豆科(Leguminosae)云实亚科(Caesalpinioideae)望江南决明(Cassia occidentalis)上; 莲子草柱隔孢 (Ramularia alternantherae), 寄生在苋科(Amaranthaceae)喜旱莲子草(Alternanthera philoxeroides)上。柱隔孢属在云实亚科和苋科是首次报道。文中为新种提供了拉丁文描述和附图。模式标本保藏于云南农业大学真菌标本室(MHYAU)。     

Air pollution exacerbates effect of allergenic pollen proteins of Cassia siamea: a preliminary report

Pollinosis caused by several allergenic proteins in pollen grains has been a major problem of healthcare in most parts of the world. Environmental factors such as air pollution are known to alter the release of allergenic pollen proteins from a variety of the plant species. Cassia siamea is commonly planted along roadsides and in industrialised areas in many parts of India. The present study reports the findings of animal experiments demonstrating the effect of air pollution on the allergenicity of Cassia siamea pollen proteins. Total white blood cell (WBC) count and lymphocyte count were significantly higher in animals that received protein extract of pollen collected from a polluted site compared to those that received protein extract of pollen collected from a non-polluted site. This was concomitant with increased production of IgE antibodies; followed by marked degranulation of mast cell leading to heighten type I hypersensitivity in these animals. These results are important for the development of a consensus linking ever-increasing pollution due to industrialisation and an increase in associated pollinosis.     

培养条件对双荚决明愈伤组织诱导的影响

以双荚决明试管苗茎段作外植体,进行光照、温度和pH值等不同培养条件的比较试验。结果表明,在温度26 ℃、12 h/d光照和12 h/d黑暗相间处理、pH 5.3的培养条件下,双荚决明愈伤组织诱导率最高,且芽丛苗的长势最佳。     

水皂角多酚的提取工艺研究

本研究通过单因素实验和正交实验 ,以提取物中水皂角总多酚含量为考察指标 ,对影响水皂角多酚提取效果的各因素进行了研究。结果表明各因素对水皂角多酚提取效果的影响程度从高到低依次为 :浸提温度 >乙醇浓度 >固液比 >浸提时间。确定了水皂角多酚的最佳提取工艺为乙醇浓度 70 % ,浸提温度 70℃ ,浸提时间 5h ,固液比 1∶10。