EFFECTS OF HELMINTHOSPORIUM VICTORIAE AND VICTORIN UPON PERMEABILITY

Wheeler, Harry, and Homer S. Black. (Louisiana State U., Baton Rouge.) Effects of Helminthosporium victoriae and victorin upon permeability. Amer. Jour. Bot. 50(7): 686–693. Illus. 1963.—Helminthosporium victoriae, the causal agent of Victoria blight of oats, produces a potent toxin called victorin. All of the symptoms of Victoria blight, both visible and biochemical, can be induced in susceptible plants either by infection with H. victoriae or by treatment with victorin. Among the effects produced both by the fungus and the toxin are marked changes in respiration and cell permeability. These are of special interest because they are characteristic of many plant diseases. This paper is concerned with the nature of changes in permeability and the possible relation of these to changes in respiration observed in tissues infected with H. victoriae or treated with victorin. Suseeptible oat tissues treated with victorin lost electrolyes when suspended and shaken in distilled water more rapidly than control tissues, and the magnitude of the effect varied with the concentration of victorin applied. Similar results were obtained with naturally infected susceptible plants but not with inoculated or victorin-treated resistant plants. The rate of electrolyte loss from victorin-treated tissue had a low temperature coefficient typical of a physical process and was not dependent upon oxygen tension. The concentration of victorin needed to produce an increase in the rate of electrolyte loss was approximately 50-fold less than that required to induce a significant increase in the respiratory rate. Changes in permeability were detected within 5 min after victorin was applied, whereas respiratory changes were not clearlyevident until after 30 min. These results indicate that if a causal relationship between these 2 phenomena exists, changes in permeability are responsible for changes in respiratory activity rather than vice versa.     

急性高原性低氧对三种小哺乳动物肝脏作用的比较

人工低气压舱模拟高原低氧,观察实验动物小白鼠、豚鼠及野生动物达乌尔鼠兔,在海拔5000米及8000米24小时内的几种生理效应,并与2300米海拔对照组进行了比较。发现随着海拔高度的升高:1.3种动物体重明显下降;2.肝糖原含量明显降低:小鼠、达乌尔鼠兔与豚鼠肝糖原在8000米时分别为2300米含量的62%,35%及 9%:3.小鼠、达乌尔鼠兔及豚鼠的肝脂肪累积量依次增大;4.肝蛋白质含量减少;5.SGPT与SGOT活力升高;6.肝细胞溶酶体的酸性磷酸酶与芳基硫酸脂酶活力升高。肝组织形态学观察结果与生化检测结果一致,豚鼠在8000米海拔时,肝细胞出现气球样变,脂肪变性及灶性液化性坏死等变化。综合分析,这3种动物对极度低氧的耐受性依顺序为小鼠、达乌尔鼠兔、豚鼠。     

长白松的木材解剖及其分类问题

关于长白松的分类问题一直有争议^[6-11],根据作者对吉林省安图县二道白河产的长白松的木材解剖研究,发现其木材的射线管胞内壁具深锯齿,颇与欧洲赤松(Pinus sylvestris Linn.)相近^{[14] [15]},但以其木射线薄壁组织细胞水平壁无纹孔和晚材最后数列管胞弦壁上存在着排列成轴向单行小形具缘纹孔来看,这又显属赤松(Pinus densiflora Sieb.et Zucc.)的特征。因此,作者认为长白松的木材结构是处于欧洲赤松与赤松之间而更偏于赤松^[10],故确认其当归属于赤松的种群范围。     

UVA的辐射效应及其分子机理

在光量子血疗法治疗肿瘤及其它疾病中,紫外线已被广泛地用作辐照光源,并取得满意效果。本文综述了近几年关于ＵＶＡ的辐射效应和分子机制研究的某些进展。     

广西柳杉木材构造、材性研究

南丹大塘山林场所产的柳杉生长良好,年轮平均宽度达0.8cm左右,比生长在南丹的杉木还要宽,在木材构造方面,柳杉管胞(纤维)的长度、直径、胞壁厚度等都稍低于杉木,其中差距较大为早材管胞长度。从木材性质来看,除年轮宽度、弦径干缩比、弦面抗劈力、冲击韧性稍大于杉木外,余均稍低于杉木;柳杉木材质量系数为中质量,强度性质为低的一级,其他强重比如顺压、抗弯等虽稍低于杉木,但在一般用途可以适应的。无论在化工原料、原木利用,交通运输、一般用器都具有一定的经济价值。     

通光藤甙元甲、乙和丙的结构——悼念蔡希陶教授

通光藤〔Marsdenia tenacissima（Roxb.）Wight et Arn.〕系云南民间治疗气管炎和抗癌药用植物。前报我们报告了通光藤甙元甲的结构的部分研究工作。自分离甙元甲的母液中我们又分得了两个少量新甙元——通光藤甙元乙和丙（tenacigenin B and C）。本文报告它们的结构研究,并在此基础上对前报所推定的通光藤甙元甲的六元氧环的立体构型提出修正。     

环境污染物对巨噬细胞的影响及生物监测意义

研究环境污染物亚硫酸盐和无机汞对小鼠腹腔巨噬细胞的影响,探讨巨噬细胞作为生物监测指示物的意义。实验取小鼠腹腔巨噬细胞分别经Na_2SO_3和HgCl_2体外培养,光镜和电镜下观察细胞形态学改变,检测其NO产量,还原MTT能力和吞噬功能。结果显示,小鼠腹腔巨噬细胞染毒后,细胞形态均发生显著改变;NO浓度明显降低,还原MTT能力受抑制,吞噬功能明显减弱(p<0.05或p<0.01)。高浓度(10~(-4)mol/L)HgCl_2细胞毒性作用显著,可致巨噬细胞坏死。实验表明,Na_2SO_3和HgCl_2对小鼠腹腔巨噬细胞具有明显损伤作用,进而直接影响巨噬细胞的非特异性防御功能。实验提示巨噬细胞可作为生物监测指示物,应用于环境污染的生物监测。     

烟蚜为害的经济损失研究

陕西渭北烟草种植区迁飞到烟田的蚜虫有6种,但只有桃蚜Myzus persicae(Sulzer)能够建立种群,造成为害。从烟草旺长开始,按烟株上蚜量和蚜虫分泌蜜露,引起霉菌滋生,污染叶面积的比例分为0、I、II、III、IV级。以未受蚜害的0级为对照,受蚜害的I、II、III、IV级的中上等烟下降分别为6.93%、13.05%、28.51%和30.94%,经济损失率分别为9.86%、23.81%、36.12%和39.59%。化学成分分析表明：I、II、III和IV级烟叶的烟碱含量分别降低10.61%、19.29%、10.61%和25.40%,还原糖分别降低15.04%、19.23%、40.98%和44.86%,蛋白质含量分别提高16.17%、31.99%、37.02%和38.72%。这就表明桃蚜为害既影响烤烟的外观质量、又影响内在品质。1头蚜虫经济损失率＝0.0695%。     

THE EFFECTS OF DEFOLIATION AND LOSS OF STAND UPON YIELD OF SUGAR BEET

Seedling pests of sugar beet cause defoliation and loss of stand. Attempts were made to assess the effects of these types of injury by means of field trials in which the defoliation and loss of stand were produced artificially shortly after singling. The main effects of these treatments were to modify the size of the plants without greatly influencing their percentage sugar content. Little loss of crop resulted until 50% of the leaf area or 50% of the plant population had been destroyed. The yield from re-sowing after removal of all the plants was inferior to that from stands depleted of half or two-thirds of their initial plant population. The relation between the results of artificial injury and the injury produced by seedling pests is briefly discussed.     

中国紫堇属曲花堇组的研究

曲花紫堇组(Sect．Rapiferae)是1936年由Fedde建立的,当时大约有20种。我们在做中国植物志的过程中,对大量标本进行了分析研究后,本组已是包括有41种的大组。模式种:曲花紫Corydalis curviflora Maxim．     

雌甾—金属卟啉的合成及其催化性质的研究

合成了雌酚酮—卟啉及其钴络合物,研究了其催化氧化异丙苯的动力学,用Lineweave-Burk法求得动力学参数V_(max)=5.506×10~(-3),K_m=6.081×10~(-2)和K_2=25.37。     

COMPARATIVE STUDIES ON RESPIRATION : XVI. EFFECTS OF HYPOTONIC AND HYPERTONIC SOLUTIONS UPON RESPIRATION.

1. In highly hypertonic solutions of sea water the rate of respiration of Laminaria agardhii is rapidly reduced. 2. In highly hypotonic solutions the rate of respiration of Laminaria agardhii is reduced somewhat less rapidly than in the case of hypertonic solutions. 3. Hypertonic solutions of NaCl, CaCl₂, and of mixtures of NaCl, and CaCl₂ in the proportion of 50:1, all caused a decrease in the rate of respiration of wheat seedlings.