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101.
All recorded host plants of Phyllotreta nemorum L. (Coleoptera: Chrysomelidae) contain glucosinolates and belong to the plant families Brassicaceae (Cruciferae), Resedaceae and Capparaceae. The acceptability of 56 plant species from 28 other plant families (non-hosts) for young larvae has been studied in the laboratory. None of these species were fully acceptable for initiations of leaf mines when intact untreated leaves were presented, and only one species, Malva silvestris L. (Malvaceae), was partially acceptable. The acceptability of some species increased when leaf discs were presented instead of intact leaves; but the highest percentages of mine initiations occurred in leaf discs treated with the glucosinolate, sinigrin. A stimulatory effect of sinigrin could be demonstrated in experiments with 7 plant species: Papaver dubium L., Papaver rhoeas L., Fumaria officinalis L., Malva silvestris L., Pisum sativum L., Campanula latifolia L. and Lactuca sativa L. The majority of species remained unacceptable even after treatment with glucosinolates.The main causes for these differences between plant species are supposed to be differences in contents of deterrents and/or other stimulants for mine initiation. These possibilities are discussed in relation to the content of allelochemicals in acceptable plants and the position of these plants in botanical classifications.
Zusammenfassung Phyllotreta nemorum L. ist ein oligophager Erdfloh, der an Cruciferen und anderen Glukosinolat-haltigen Pflanzenarten gebunden ist. Die Imagines fressen Löcher in die Blätter und die Weibchen legen ihre Eier in den Boden. Die Larven sind Blattminierer. Nach dem Schlüpfen im Boden klettern sie an die Pflanzen hoch, und die Einbohrung und der Anfang der Minierung erfolgt in eines der unteren Blätter der Wirtspflanze.Die Wirkung von Glukosinolaten auf die Einbohrung von Junglarven in Pflanzenarten, die keine natürliche Inhalt von Glukosinolaten haben, ist in Laborexperimenten untersucht worden. 56 Pflanzenarten aus 28 Familien wurden präsentiert teils als unbehandelte Blätter und teils als Glukosinolatbehandelte Blattscheiben. Unbehandelte Blätter von nicht-Glukosinolathaltigen Arten waren immer unbefriedigend für die Larven. Nur in eine Art, Malva silvestris L. war die Frequenz der Einbohrung ein bisschen höher als 10%. Eine signifikante Erhöherung der Anzahl eingebohrten Larven nach der Sinigrin-behandlung erfolgte in 7 Pflanzenarten: Papaver dubium L., P. rhoeas L., Fumaria officinalis L., Malva silvestris L., Pisum sativum L., Campanula latifolia L. und Lactuca sativa L. Doch blieben die meisten Pflanzenarten (84%) auch nach der Sinigrin-Behandlung unbesiedelt.Pflanzenarten, die nach der Sinigrin-Behandlung nicht besiedelt werden enthalten vielleicht frasshemmende Stoffe, oder ihnen fehlen noch weitere Frass-stimulierende Stoffe. Diese Möglichkeiten werden diskutiert in Zusammenhang mit den Inhalt von Allelochemikalien in besiedelten Pflanzenarten und mit ihrer taxonomischer Position.
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102.
Twelve forage grass accessions including 11 accessions of Brachiaria Griseb, were evaluated in a glasshouse for host plant resistance to nymphs and tolerance to feeding damage caused by adults of Zulia colombiana (Lallemand) (Homoptera: Cercopidae). Resistance to nymphs was evaluated with a technique that provided uniform environmental conditions and abundant feeding sites. B. brizantha Stapf (cv. Marandú) was the most resistant of the accessions tested based on nymphal mortality, duration of nymphal stadia, and weight of adult females. Andropogon gayanus Kunth, resistant to spittlebug attack in the field, was susceptible under the conditions of this study. While growth habit and rooting characteristics may contribute to field resistance, other resistance factors are present within the genus Brachiaria, particularly in the case of B. brizantha cv. Marandú. The number of insect-days causing severe damage in the most tolerant species (B. dictyoneura Stapf and B. humidicola Schweick) was approximately six times greater than that necessary to cause the same level of damage to the most susceptible species (B. ruziziensis Germain & Evrard and B. decumbens Stapf). No difference was found in regrowth capacity between infested and noninfested plants within accessions. There was a significant positive correlation between number of insect-days causing severe damage (tolerance) and regrowth of infested plants.
Résumé Brachiaria est une graminée fourragère prometteuse pour les sols tropicaux acides, saturés d'aluminium. Z. colombiana est un Cercopidae très répandu, limitant l'utilisation de Brachiaria en Amérique Latine. La résistance (antibiose et tolérance) à Z. colombiana, de Brachiaria d'origines diverses a été examinée. B. brizantha cv. Marandù s'est révélé le plus résistant d'après la forte mortalité larvaire, la prolongation du développement larvaire, et le poids réduit des femelles adultes de Z. colombiana. Andropogon gayanus, résistant dans la nature, s'est révélé sensible. Ces résultats suggèrent que cette résistance de A. gayanus dans la nature pourrait être due à la structure du végétal et à son mode de croissance. Dans le cas de B. brizantha cv. Marandù, des facteurs supplémentaires de résistance, mis en évidence à partir de différents modes de croissance, ont été éliminés, de façon à identifier les mécanismes de l'antibiose présents chez Brachiaria. Une grande gamme de résistance aux attaques alimentaires a été observée chez Brachiaria. Les plus résistants ont besoin de 6 fois plus de jours d'attaque par Z. colombiana pour provoquer les dégâts observés sur individus sensibles.
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103.
U. D. Bongale 《Hydrobiologia》1989,171(2):103-106
Six new taxa including two new species (Cosmarium bourrellyi Bongale sp. nov. andC. desikacharyi Bongale sp. nov.) and four new varieties (C. auriculatum var.protrusum Bongale var. nov.,C. pachydermum var.inflatum Bongale var. nov.,C. pseudoconnatum var.tuberculans Bongale var. nov. andC. quadrum var.rotundatum Bongale var. nov.) are reported. Algae were collected from a paddy field at Belgaum.  相似文献   
104.
After uptake of microbial ferrisiderophores, iron is assumed to be released by reduction. Two ferrisiderophore-reductase activities were identified in Escherichia coli K-12. They differed in cellular location, susceptibility to amytal, and competition between oxygen and ferrichrome-iron(III) reduction. The ferrisiderophore reductase associated with the 40,000×g sediment (membrane-bound enzyme) was inhibited by 10 mM amytal in contrast to the ferrisiderophore reductase present in the 100,000×g supernatant (soluble enzyme). Reduction by the membrane-bound enzyme followed sigmoid kinetics, but was biphasic in the case of the soluble enzyme. The soluble reductase could be assigned to a protein consisting of a single polypeptide of M r 26000. Reduction of iron(III) by the purified enzyme depended on the addition of NADH or NADPH which were equally active reductants. The cofactor FMN and to a lesser degree FAD stimulated the reaction. Substrate specificity of the soluble reductase was low. In addition to the hydroxamate siderophores arthrobactin, schizokinen, fusigen, aerobactin, ferrichrome, ferrioxamine B, coprogen, and ferrichrome A, the iron(III) complexes of synthetic catecholates, dihydroxy benzoic acid, and dicitrate, as well as carrier-free iron(III) were accepted as substrates. Both ferrisiderophore reductases were not controlled by the fur regulatory system and were not suppressed by anaerobic growth.Abbreviations DHB dihydroxybenzoic acid - MECAM 1,3,5-N,N,N-tris-(2,3-dihydroxybenzoyl)-triamino-methylbenzene - MECAMS 2,3-dihydroxy-5-sulfonyl-derivative of MECAM  相似文献   
105.
Abstract. 1. We tested the hypothesis that survival and sources of mortality of the leaf-folding sawfly ( Phyllocolpa sp.) varied significantly among host plants of the arroyo willow ( Salix lasiolepis Bent ham).
2. Survival of the leaf folder differed among field and potted willows in a common environment in two of three cases, and sources of mortality differed among plants in four of five cases.
3. Egg mortality differed among field plants but not among the potted willow plants.
4. Larval mortality and parasitism differed among field and potted willows in 2 years, and appeared to be compensatory mortality sources.
5. Leaf folder density among plants was not generally correlated with percentage of leaf folds with no egg (galls formed but no subsequent oviposition), percentage survival, or percentage mortality, indicating a general lack of density dependence.
6. The proportion of folds with no egg oviposited differed significantly among field and potted plants, and was only correlated with survival or sources of mortality in one of three years.
7. The data support the hypothesis that host plant genotype affects the interaction of the leaf folder with its natural enemies, and thus represents a three trophic level interaction.  相似文献   
106.
抗阿特拉津转基因大豆植株后代的遗传分析   总被引:9,自引:0,他引:9  
本试验用阿特拉津溶液涂抹、荧光诱导动力学检测、分子杂交等方法对抗阿特拉津转基因大豆植株的后代进行了鉴定,在第二代及第三代中检测到了抗性基因的存在,表明从龙葵中得到的此抗阿特拉津 psbA 基因不仅能导人大豆叶绿体基因组中获得表达,而且可以遗传到后代。  相似文献   
107.
Summary Axillary bud expiants from South Pacific (Solomon Islands) taro, Colocasia esculenta var. esculenta cv. Akalomamale (Araceae) cultured on a modified Murashige-Skoog medium containing 1 mg NAA 1–1 and TE formed callus and produced multiple plantlets. Explants died if NAA was present at levels lower than 0.1 mg 1–1. BA was not required and may have been inhibitory. Plantlets developed faster and became larger following transfer to a hormone-free medium two weeks after the start of culture. Fully grown plants were established in a potting mix and are growing well in a greenhouse.Abbreviations BA benzyladenine - BM basal medium - Ca Colocasia esculenta var. antiquorum - Ce Colocasia esculenta var. esculenta - Ck cytokinin(s) - CW coconut water - HSMSM half strength Murashige Skoog macroelements - HSMS half strength Murashige and Skoog medium - IM initial medium(ia) - MS Murashige and Skoog medium - NAA naphthaleneacetic acid - SM second medium - TE taro corm extract - UCI University of California, Irvine  相似文献   
108.
A method to obtain plants from embryogenic callus of Brassica nigra and protoplasts of hypocotyl expiants is described. Callus was initiated on Murashige and Skoog medium containing kinetin (kn) and 2,4-dichlorophenoxy acetic acid (2,4-D). Lowering of auxin induced embryo formation. Supplementation with gibberellic acid (GA3) enhanced embryogenic response tenfold. Passage through liquid medium devoid of growth regulators was essential for the growth of embryos. Secondary embryos were produced on transfer to solid basal medium. Embryogenic callus retained its morphogenic ability even after 12 subcultures. Both primary and secondary embryos produced fertile plants. Hypocotyl-derived protoplasts were also regenerated to plants following the same protocol. The survival of plants on transfer to soil was about 80%. The seeds from plants derived from callus and protoplasts were viable.Abbreviations 2,4-D 2,4-dichlorophenoxy acetic acid - NAA naphthalene acetic acid - IAA indole acetic acid - kn kinetin - GA3 gibberellic acid  相似文献   
109.
Investigations were made of the growth ofNelumbo nucifera, an aquatic higher plant, in a natural stand in Lake Kasumigaura. A rise of 1.0 m in the water level after a typhoon in August 1986 caused a subsequent decrease in biomass ofN. nucifera from the maximum of 291 g d.w. m−2 in July to a minimum of 75 g d.w. m−2. The biomass recovered thereafter in shallower regions. The underground biomass in October tended to increase toward the shore. The total leaf area index (LAI) is the sum of LAI of floating leaves and emergent leaves. The maximum total LAI was 1.3 and 2.8 m2 m−2 in 1986 and 1987, respectively. LAI of floating leaves did not exceed 1 m2 m−2. The elongation rates of the petiole of floating and emergent leaves just after unrolling were 2.6 and 3.4 cm day−1, respectively. The sudden rise in water level (25 cm day−1) after the typhoon in August 1986 caused drowning and subsequent decomposition of the mature leaves. Only the young leaves were able to elongate, allowing their laminae to reach the water surface. The fluctuation in water level, characterized by the amplitude and duration of flooding and the time of flooding in the life cycle, is an important factor determining the growth and survival ofN. nucifera in Lake Kasumigaura.  相似文献   
110.
湖北省蟹类地理分布的分析结果,古北界和东洋界的划线以31°N上下为过渡区,中部以汉水为界,113°E以东则逐步转向黄淮平原区,因此该省不仅是南北的转折,也是东西的交接地带。文中报道了两个新亚种:Sinopotamon denticulatum styxum S.depressum obliquum。  相似文献   
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