应用~(125)碘、~(14)碳标记化合物研究4-碘苯氧乙酸(增产灵)在水稻上的吸收、运转和积累过程

以~(14)C-氯代乙酸钠制备~(14)C-增产灵;以 Na~(125)I制备~(125)I-增产灵。在孕穗期或湖浆初期,采取叶面涂布、喷施或淋浇根部方法,将标记物分别引进水稻体内。 涂布~(125)I-增产灵(1000 ppm,0.1毫升)于剑叶面3小时后,标记物在叶片中已达附着量的75.2％;一部分标记物并从叶片传递至叶鞘、茎、穗及其它叶片,其中以叶鞘的积累量较多。 叶面喷施~(125)I-增产灵(100 ppm),l小时内渗入量为附着量的26.5％,随时间延长,吸收量增加。标记物在叶片积累量最多,叶鞘次之,运入茎与穗很少,加入0.1％肥皂液可增加叶面药液附着最及渗入量,但不会使叶鞘、茎、穗中的积累量增多。 通过根系吸收的~(125)I-增产灵大部分留在根内,少部分向上运转,以叶鞘积累量较多,茎部次之,叶片及穗部运入量很少。 在水稻生育后期喷施增产灵,糙米中的标记物残留量在2ppm以下。 在显微放射自显影中,~(14)C-增产灵的轨迹首先在茎的维管束及其周围细胞中密集出现,其后分散在茎叶的薄壁组织中。标记物较多地积聚于叶、茎中,推论增产灵有调节韧皮部的运输和动员贮藏物向代谢中心运输的作用。     

辛硫磷在茶叶中残留消解动态的研究

本文介绍了有机磷杀虫剂辛硫磷在茶树上的残留消解动态。试验是1973年在杭州进行,用50%辛硫磷乳剂800倍稀释液喷洒在遮荫条件和自然日照条件下的茶树上,每天采摘鲜叶,并制成成茶,用薄层层析法测定鲜叶及成茶中的辛硫磷残留量。本文还介绍了在室内条件下进行的辛硫磷光敏性试验结果。 根据室内试验结果表明,辛硫磷是一种光敏性极强的农药。在紫外光源照射下,4小时后光解99%左右。在自然漫射光下,4小时后光解50%以上,但在黑暗条件下较稳定,8小时仅分解17.5%。根据三种农药测定结果的比较,光敏性依如下次序递减:辛硫磷>马拉硫磷>乙硫磷。田间残留量测定资料进一步证实了这一实验结果。在自然日照条件下,根据实验结果,喷后4小时鲜叶中辛硫磷残留量下降85%以上,二天后即为痕迹量到无残留。成茶中一天后一般残留量降至0.5 ppm以下,二天后即无残留;但在遮荫条件下辛硫磷消解速度显著变慢,喷药后4小时鲜叶中残留量下降63%,为自然日照条件下的2.9倍,二天后仍有4.12 ppm,五天后仍有痕迹量残留。成茶中残留量一天后为4.02 ppm,五天后仍有痕迹量残留。 鲜叶中辛硫磷残留量经加工后消失50—80%左右。 本文提出了茶园中喷施50%辛硫磷800倍液后距采摘的安全间隔期为3天(晴天)和5—6天(阴天)。     

烟草叶片中草酸形成及其向下运输(简报)

水培条件下烟草根、茎、叶中的草酸含量呈极显著正相关。光照条件下用14CO2饲喂烟草叶片后,叶中很快有大量14C-草酸形成,随后分别在茎、根中检测到14C-草酸,时间上相差约1h。这表明烟草叶片通过光合固定CO2,其光合产物可很快转化为草酸,部分草酸可通过茎向根部运输。     

利用显微放射自显影技术研究~(14)C标记4-碘苯氧乙酸(增产灵)在水稻各器官的积聚与分布

在水稻孕穗期、开花期,用~(14)C标记增产灵涂布剑叶(功能叶)。放射自显影表明:涂布6小时后~(14)C-增产灵就在水稻茎的维管束细胞和叶脉中发现,其后主要集中在同化组织茎的薄壁细胞和叶的叶肉细胞(栅栏组织、海绵组织)中。6小时后在水稻花中也偶尔发现,2天后已较多的进入花器官,但只分布在颖片、花丝、花粉囊和子房壁等营养性组织中,而生殖细胞花粉粒和胚珠中未发现~(14)C-增产灵分布。本研究从细胞水平为阐明增产灵的作用机理提供一些理论依据。     

小麦在干热风条件下的生理变化 Ⅱ.干热风对小麦灌浆期~(14)CO_2同化作用和~(14)C-同化产物累积的影响

小麦在灌浆期受干热风的影响,叶绿素遭受破坏,降低了同化~(14)CO_2的能力。~(14)C-同化产物在叶片、茎秆和籽粒中的含量也相应地下降了。这与叶片和籽粒内糖分含量的分析结果是一致的。干热风还使~(14)C-同化产物在小麦体内的运转发生改变。在叶片和茎秆中降低了醇溶部分的含量而使石油醚溶部分含量增高。茎秆内的贮藏物质加速降解外运,而运入籽粒内的同化产物则加快了转化与贮藏。小麦受害后给以适宜的生长条件,其功能仍不能恢复。这是最终造成籽粒产量和品质下降的重要生理原因之一。     

水稻秧苗对~(14)C-MET的吸收与运转(简报)

水稻种子吸收的~(14)C-MET有80％滞留在颖壳内,出苗后地上部和地下部各器官均有~(14)C-MET分配;叶片吸收的~(14)C-MET可运输至地上部各器官,但多数滞留在原吸收部位,不运输到根部;根系从土壤中吸收~(14)C—MET运转到地上部各器官。土施的~(14)C-MET多数滞留在0～5cm的表层土壤。     

应用辛硫磷拌种防治蛴螬的研究

蛴螬取食萌发种子和残存种皮是药剂拌种杀虫保苗的生物学依据。应用高效低毒低残留农药——辛硫磷拌种,可以逐步取代当前常用的高残留、剧毒类农药.改变目前防治现状。 应用种子上有效含量0.0375%的辛硫磷拌种,保苗效果稳定在90%以上,在土壤中残效时间为25天,且对小麦、玉米、高梁等作物无药害表现。经47万余亩麦田示范应用,一致表现药效稳定,人畜安全。 拌种还可兼治蝼蛄,惟后期出现死苗,保苗效果稍差。采用拌种加颗粒剂方法,可以提高早春和秋播拌种的药效。     

降解辛硫磷农药菌株的筛选

从农药厂附近的土壤中,分离得到两株降解辛硫磷有机农药能力较强的菌株,编号为1631、2021。经鉴定均属于PREVOT系统中的不动芽孢杆菌属(Bacteridlun)。在辛硫磷含量为50ppm的模拟废水中,1631号菌株把辛硫磷降解为无机磷的转化率为33.7%,而2021号菌株为36.6%。两个菌株在培养特性、形态特征及生理生化特性方面均是相似的。     

利用光合细菌进行微生物修复：一种降低辛硫磷在养殖水中积累的低成本方法

【背景】中国是农业生产大国,渔林农牧占比庞大。有机农药无论在畜牧业还是水产养殖业都有广泛的应用。有机磷农药(Organophosphorus Pesticide,OP)是应用最广泛的有机农药,具有低毒和不易残留的优点。OP在水体中大量积累可通过生物富集作用间接影响人体健康,由此产生的生殖毒性不容忽视。光合细菌作为环境友好型水体有益菌,部分菌种具有降解有机农药的功能。【目的】自上海海洋大学明湖中分离纯化得到一株光合细菌(编号SPZ)。探究其对辛硫磷的耐受程度及降解效果,为养殖水体中有机磷农药的生物降解提供目的菌株。【方法】利用16S rRNA基因序列分析方法对目标菌株进行种属鉴定;利用紫外分光光度法测定分离菌株SPZ和标准菌株ST在不同接种量下的OD660并测定实验周期内光合细菌在不同浓度辛硫磷中OD660的变化趋势,以示辛硫磷对光合细菌的毒性作用;利用高效液相色谱法(High Performance Liquid Chromatography,HPLC)测定菌株对水体辛硫磷的降解能力;通过HPLC测定加热致死菌与活菌对水体辛硫磷的降解能力,确定菌株对辛硫磷的降解方式。【结果】16S r...     

不同水分梯度下楸树苗期生长及光合特征比较

以1a生楸树根插苗为试验材料, 设置95%—100%FC、85%—90%FC、70%—75%FC、50%—55%FC等不同梯度的土壤含水量, 对生长旺季的光合特征及生长量进行测量, 研究苗期楸树对不同土壤水分含量的生长及光合特征响应。结果显示: 高土壤含水量(≧85%FC)和低土壤含水量(≦75%)地径和苗高生长量差异显著(P<0.05), 随着土壤含水量逐渐下降, 地径和苗高生长量、根重、茎重及根干比均呈下降趋势。光合特征比较发现, 上午净光合速率显著高于下午, 净光合速率的日变化主要直接受制于气孔因素; 85%—90%FC处理叶片的净光合日总量最大, 50%—55%FC处理叶片的净光合日总量最小。在所有光强梯度下, 高土壤水分含量处理(≧85%FC)的叶片净光合速率均明显较高, 尤其是85%—90%FC处理, 光利用能力和光合潜力都具有较大优势。从生长和光合特征综合分析结果可以看出, 四种处理中85%—90%FC处理最有优势和潜力, 是楸树苗期生长最为适宜的土壤含水量。     

蚜虫寄主植物与取食部位的多样性

在中国科学院动物研究所已有标本采集记录和国内外文献资料的基础上,分别从蚜虫类Aphidina科级和属级阶元系统研究世界范围内蚜虫寄主植物与取食部位的多样性.蚜虫的寄主植物种类繁多,涉及267科2120属,尤其以菊科、禾本科、豆科、伞形科、唇形科、蔷薇科、茜草科、兰科、壳斗科、杨柳科、胡桃科等植物为主.13科蚜虫的寄主植物差别很大:在科级水平,球蚜科Adelgidae、纩蚜科Mindaridae和平翅绵蚜科Phloeomyzidae的寄主植物类群比较单一,蚜科Aphididae和瘿绵蚜科Pemphigidae的寄主植物范围最为广泛;在属级水平,各属蚜虫间寄主植物也有明显差异,有143属蚜虫的寄主植物多于2科,其中蚜科的属占多数,蚜属Aphis、瘤蚜属Myzus、长管蚜属Macrosiphum、粗额蚜属Aulacorthum和声蚜属Toxoptera的寄主植物最多,各超过100科290属.在不同的寄主植物上寄生着不同种类的蚜虫,其中16科47属寄主植物上寄生的蚜虫多于14属.蚜虫在寄主植物上的取食部位丰富多样,可分为7类,分别为叶片、嫩梢、嫩枝、茎、花、根部、果实等.以叶片、茎、嫩枝和嫩梢为蚜虫主要取食部位.平翅绵蚜科主要取食嫩枝、茎和根部,短痣蚜科Anoeciidae主要取食叶片、嫩梢和根部,球蚜科、群蚜科Thelaxidae和毛管蚜科Greenideidae取食叶片、嫩梢、嫩枝和茎等部位,纩蚜科取食叶片、嫩梢、茎和花等部位,大蚜科Lachnidae和斑蚜科Drepanosiphidae除取食叶片、嫩梢、嫩枝、茎等部位外,前者还在根部取食,后者还寄生在果实上,根瘤蚜科Phylloxeridae在除花以外的其它6个部位取食,蚜科、瘿绵蚜科和毛蚜科Chaitophoridae的取食部位最为多样,它们在上述7个部位均可取食.还初步讨论了在不同寄主植物上蚜虫物种的分化,以及蚜虫与寄主植物之间的对应关系.     

4种鼠尾草属植物根、茎、叶中脂溶性成分的分布差异性

为了说明4种鼠尾草属植物脂溶性成分在根、茎、叶中的分布情况,本文采用了组织化学定位和HPLC图谱分析相结合的方法,对4种鼠尾草属植物不同部位的脂溶性成分进行了分析.结果表明:4种鼠尾草属植物的根、茎、叶中脂溶性成分的分布有差异,根中脂溶性成分分布于周皮,茎、叶中脂溶性成分分布于表皮.丹参和白花丹参根中的脂溶性成分主要是丹参酮ⅡA、丹参酮Ⅰ和二氢丹参酮Ⅰ,鼠尾草和药用鼠尾草根中仅含丹参酮ⅡA,不含丹参酮Ⅰ和二氢丹参酮Ⅰ.茎、叶中的脂溶性成分不是丹参酮ⅡA、丹参酮Ⅰ和二氢丹参酮Ⅰ.脂溶性成分的种类和含量随品种和引种地的不同而产生差异.这一结果明确了脂溶性成分在4种鼠尾草属植物不同部位的确切分布,为准确用药提供了依据.     

AN ANALYSIS OF THE GROWTH RESPONSE OF YOUNG TOMATO PLANTS TO INFECTION BY VERTICILLIUM ALBO-ATRUM: II. THE PRODUCTION OF GROWTH SUBSTANCES

Bioassays on ether-soluble acid extracts from healthy and Verticillium -infected tomato plants, showed the presence of substances inhibiting growth of wheat coleoptiles in both healthy and infected leaves and stems, but the amounts were greater in the infected.
Assays of infected stems and leaves showed increases in growth-promoting activity expressed as indole-3-acetic acid equivalents (IAAe), up to 200% of those for healthy controls.
Similar assays of cultures of V. albo-atrum showed growth-promoting activity. No acid substance capable of inhibiting the growth of wheat tissue was detected in the culture filtrate. IAA was identified by colour test with Ehrlich's reagent on chromatograms from extracts of both infected stems and fungal culture filtrates.
The vertical distribution of IAAe was determined in healthy and infected plants at the eight-leaf stage by assaying individual leaves and four stem segments separately. In healthy plants the IAAe content was greatest in the young leaves (6–8) but no gradient was observed as between leaves 1–5. In infected leaves increases over the controls were found in leaves, 1, 3 and 6 and a decrease in leaf 8.
In healthy stems IAAe was highest in the distal segment and infected stems showed higher values at all four levels, with the relative increase greatest in the distal region.
It is suggested that the major part of the Verticillium syndrome including petiolar epinasty, tylosis, pith hyperplasia and the formation of adventitious roots is the result of an accumulation of growth substances in infected tissue.     

CHARACTERIZATION OF STARCH GRAINS IN THE NONARTICULATED LATICIFER OF EUPHORBIA PULCHERRIMA (POINSETTIA)

Starch grain morphology in laticifer amyloplasts of Euphorbia pulcherrima Willd. (poinsettia) was examined for evidence of starch metabolism in vegetative and flowering plants. Laticifer starch grains in vegetative plants were rod shaped with lengths ranging from 3 to 60 μm. Average grain size was significantly larger in stems than leaves, and in older than younger tissues. Starch grain length frequency was unimodal and approximated a normal probability distribution in stems, but was skewed positively toward smaller grains in leaves. Frequency distributions were shifted toward larger grains in older tissues. Under short-day photoperiod (flowering) conditions, round starch grains formed in latex of stems, and the average length of rod-shaped grains decreased in latex of stems and leaves. Round grains did not occur in laticifers of leaves or bracts. Round starch grains often occurred in aggregates of two or more subunits. Changes in size and shape of latex starch grains indicate that amyloplasts in fully differentiated laticifers metabolize starch. Identification of metabolically active amyloplasts in differentiated laticifers suggests that the function of these organelles may involve starch mobilization under certain physiological conditions.     

Calotropis procera as a source of plant hydrocarbons

Calotropis procerawas evaluated as a potential source of hydrocarbons. Hexane Soxhlet extractions of oven-dried whole plants, stems, leaves and pods (≧6mo of age) yielded 4.35, 3.83, 5.13, and 9.37% (w/w) hexane extract (HE), respectively. The HE from whole plants has a density of 0.9299 glcm3, 0.71% total ash, 9973.4 callg and 78.03, 11.22 and 10.71% carbon, hydrogen and oxygen, respectively. Similar values were obtained from stems, leaves and pods when analyzed separately. Methanol Soxhlet extractions of residues previously extracted with hexane yielded 16.14, 18.50, 12.15 and 20.68% (w/w) methanol extract (ME) from whole plants, stems, leaves and pods, respectively. The ME from whole-plant residues had a density of 1.2267 glcm3, 12.05% total ash, 4,647.4 callg, and 40.88, 6.86, and 30.05% carbon, hydrogen and oxygen, respectively. Similar values were obtained from stems, leaves and pods when analyzed separately.     

EVIDENCE FOR THE REPAIR OF OZONE-INDUCED MEMBRANE INJURY

The increase in [¹⁴C]-2-deoxy-D-glucose uptake by leaf discs 24 hr after fumigation was used as a measure of ozone injury to pinto bean leaves (Phaseolus vulgaris). This method showed that the primary leaves were most affected by ozone when plants were 10 to 12 days old, which coincided with the time of maximum leaf necrosis. However, 8-day-old plants, which had no visible leaf injury, still showed a higher uptake rate than controls, indicating that injury occurred at the cellular level. In these younger plants, uptake was shown to return to normal over a 5 day period. Moreover, the rate of this “repair” was retarded by cold or continuous darkness, enhanced by continuous light, and very markedly increased by glucose applied to the leaves. The timing of the glucose application was not critical, nor did H₂O or mannitol have an effect. The results suggest that ozone injury at the cellular level can be repaired by energy-dependent processes so that necrosis of the leaf tissue does not occur. These experiments also show that conditions and treatments after ozone exposure can alter the degree of ozone injury.     

STUDIES ON THE UPTAKE AND TRANSLOCATION OF STREPTOMYCIN BY PEACH SEEDLINGS

Measurements of the antibiotic activity in the foliage of peach seedlings, kept with their roots in mineral nutrient solutions containing streptomycin, showed that streptomycin passed into the foliage and sometimes reached concentrations above those of the solutions surrounding the roots. The amount of the antibiotic in leaves varied with the time that roots were kept in the solutions and with the streptomycin concentrations of the solutions. Lower leaves contained much more than upper leaves.
Adding macerated leaf tissue to streptomycin solutions decreased the amount of streptomycin detectable in the supernatant liquid more than could be accounted for by dilution or alteration of pH.
Streptomycin first affected plants by decreasing apical growth, but at higher concentrations it caused chlorotic and necrotic areas on leaves and stems.     

木本植物对大气重金属污染物——铅、镉、铜、锌吸收积累作用的研究

对环境污染除必须采取人工治理措施外,还必须充分发挥自然净化作用,才能取得经济合理和维护生态系统动态平衡的目的。 绿色高等植物特别是树木,对环境污染起着明显的净化和改善作用。因为它们的生物产量高,占有很大的空间,有巨大的根、茎、叶面积作用于环境,并对污染物具有一定的吸收积累或降解作用;生活周期长,有较长的时间与周围环境相互作用与影响,同时吸收积累的污染物质不会在短期内转移释放到环境中;此外,大部分树木是以保护环境或生产木材为主要目的,因而吸收积累的污染物不进入食物链对人产生危害。所以树木在保持和维护生态系     

鼎湖山南亚热带常绿阔叶林植物营养元素含量分配格局研究

在鼎湖山南亚热带常绿阔叶林中,植物叶片营养元素含量为Ｎ ０．９４６％－２．５３５％,Ｐ ０．０３０－０．１２７％,Ｋ ０．６１４％－１．８３３％,Ｃａ ０．４４２％－１．９９５％,Ｍｇ ０．０２４％－０．１８８％。叶片各营养养元素间相关性较差,仅Ｐ与Ｍｇ及Ｍｇ与Ｋ之间存在显著的线性相关。叶片Ｎ元素平均含量在各层中的序列为：乔木Ⅲ〉乔木Ⅱ〉乔木Ⅰ〉灌木〉藤本〉草本;其它营养元素浓度随层次分配的规律性     

马尾松疱锈病菌及转主寄生的研究

马尾松疱锈病是一种严重的病害,病菌的性孢子、锈孢子(O、Ⅰ)阶段发生在马尾松(Pinus massoniana Lamb.)枝干上,夏孢子、冬孢子(Ⅱ、Ⅲ)阶段出现在玄参科的阴行草(siphonostegia chinensis Benth.)叶背、茎、萼片及果实上。取马尾松病干上的锈孢子人工接种,只有阴行草感病,产生与自然状态下相同的典型症状。该病菌性孢子器平展或不规则形,生于皮下;锈孢子表面塔状疣突的基部两层环纹很厚;冬孢子柱较小,长度很少超过800μm。因此认为,马尾松疱锈病菌是松芍柱锈菌[Cronartium flaccidum(Alb.et Schw.)Wint.]的阴行草专化型(C.flaccidum f.sp.siphonostegium)