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1.
报道了陕西省胡椒科一新记录属——胡椒属(Piper Linn.)及一新记录种——竹叶胡椒(P.bambusifolium Y.C.Tseng)。  相似文献   

2.
报道了陕西省萝藦科一新记录属——吊灯花属(Ceropegia Linn.)及一新记录种——宝兴吊灯花(Ceropegia paoshingensis Tsiang et P.T.Li)。  相似文献   

3.
报道了广西罂粟科一新记录属——黄药属(Ichtyoselmis LidénFukuhara)及一新记录种黄药[Ichtyoselmis macrantha(Oliver)Lidén]。  相似文献   

4.
报道福建省莎草科一新记录属——剑叶莎属(Machaerina Vahl),一新记录种——圆叶剑叶莎[Machaerina rubiginosa (Sol. ex G. Forst.) T. Koyama],凭证标本存放于福建农林大学林学院树木标本室(FJFC)。  相似文献   

5.
独尾草属(Eremurus M. Bieb)全世界约有20多种,主要分布于中亚及西亚的山地和平原沙漠地区。我国产4种,其中独尾草(E. chinensis Fedtsch. )主要分布于四川、云南和西藏,在甘肃南部的岷县、舟曲、武都、文县也有分布。其染色体数目和核型迄今未见报道,本文对采  相似文献   

6.
报道了海南莎草科一新记录属——针蔺属(Trichophorum Persoon)及该属一新记录种——玉山针蔺[T.subcapitatum(Thwaites et Hooker)D.A.Simpson].  相似文献   

7.
报道了陕西省兰科一新记录属——套叶兰属(Hippeophyllum Schltr.)及一新记录种——套叶兰(Hippeophyllum sinicwn S. C. Chen et K. Y. Lang)。  相似文献   

8.
报道了中国大戟科一新记录属——小果木属(Micrococca Benth.)。小果木Micrococca mercurialis(L.)Benth.首次在海南发现。  相似文献   

9.
秦岭兰科一新记录属--蝴蝶兰属   总被引:2,自引:0,他引:2  
报道了秦岭兰科一新记录属——蝴蝶兰属,华西蝴蝶兰Phalaenopsis wilsonii Rolfe.。  相似文献   

10.
报道云南樟科一新记录属——土楠属(长果土楠).增订了长果土楠的特征,并绘制了该种的分布图.  相似文献   

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The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

14.
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

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Difficulties in controlling outbreaks of Western flower thrips, Frankliniella occidentalis, have obstructed the widespread adoption of biological control in many ornamental crops. The efficacy of the predatory mite, Neoseiulus cucumeris, in controlling F. occidentalis on two cultivars of cyclamen was tested in glasshouse experiments. The establishment and development of F. occidentalis populations was compared in three treatment introductions of N. cucumeris (50, 200 and 350 mites m -2 per week) and an untreated control. F. occidentalis were sampled in the flowers over eight weeks and counted into different life stages. No differences were observed between the two cultivars. All treatments with the predator resulted in a decline in numbers of F. occidentalis compared to the untreated control. Although the proportion of first instar F. occidentalis was similar in all treatments, the level of control varied with the number of N. cucumeris introduced. Lower populations of F. occidentalis, combined with a more rapid decline in their numbers, were observed at the 200 and 350 mites m -2 rates. Numbers of F. occidentalis remained low in the 350 N. cucumeris m -2 rate and the proportion of second instar F. occidentalis in the samples was consistently lower than in the other treatments. Trap counts of adult F. occidentalis were strongly correlated with the numbers of both adult and total F. occidentalis in flower samples. High inoculative releases of N. cucumeris early in the flowering cycle followed by frequent low introductions of predators should provide a strong basis for preventative control of F. occidentalis and other thrips species on cyclamen.  相似文献   

17.
Highlights
1. 13 strains of H7N9 viruses from laying hens in 2020 and 2021 were identified.
2. H7N9 viruses in China comprised at least 11 genotypes.
3. H7N9 viruses are high pathogenic in chickens, not in ducks.
4. The most H7N9 viruses cross-reacted poorly with H7-Re3 antiserum.
5. The H7-Re3 vaccine was unable to prevent H7N9 infection.  相似文献   

18.
The fungi, Hirsutella rhossiliensis and Hirsutella minnesotensis, are two endoparasites of second-stage juveniles (J2) of the soybean cyst nematode (SCN), Heterodera glycines. The objective of this study was to screen for effective fungal isolates to control the nematode in laboratory and greenhouse assays. A total of 93 isolates of H. rhossiliensis and 25 isolates of H. minnesotensis were evaluated for parasitism of SCN J2 on cornmeal agar. Percentage of SCN J2 parasitized by the fungi varied among the fungal isolates. Most H. rhossiliensis isolates parasitized a high percentage of J2. The isolates of H. rhossiliensis obtained from bacteria-feeding nematodes, however, generally did not parasitize J2 on agar. H. minnesotensis parasitized fewer J2 on agar than did H. rhossiliensis . Forty isolates of H. rhossiliensis and four isolates of H. minnesotensis that parasitized a high percentage of J2 on agar were evaluated for their biocontrol potential in soil treated with microwave heating. Most isolates selected from the agar assay also parasitized a high percentage of J2 in the soil but there was variation among isolates. Pathogenicity of 14 isolates of H. rhossiliensis and four isolates of H. minnesotensis to the SCN was also investigated in the greenhouse using untreated field soil. Most isolates of H. rhossiliensis reduced SCN population density and increased plant growth when compared with 1% corn-grits control (culture media). One isolate (OWVT-1) of H. rhossiliensis reduced the SCN egg density by 95% and J2 density by 98% when compared with the control. Isolates of H. minnesotensis, however, neither reduced SCN density nor increased plant growth in the greenhouse.  相似文献   

19.
Three remarkable new genera of conidial lichen-forming fungi, with pycnidial or acervular conidiomata are described and illustrated.Hastifera tenuispora gen. et spec. nov. from the South-Tyrol, Italy, is characterized by very long and narrow hyaline conidia produced in pycnidial conidiomata immersed in thalline warts.Lichingoldia gyalectiformis gen. et spec. nov. from rocks subject to inundation by freshwater in Norway has long sigmoidly curved conidia which appear to be adapted to dispersal in water.Woessia fusarioides gen. et spec. nov. from aQuercus stump in the Burgenland, Austria, has a finely granular thallus and disc-like conidiomata producing falcate conidia; this species is also of interest in that it hasChlorella as the photobiont. The recently described hyphomyceteCheiromycina flabelliformis B. Sutton is reported from Austria for the first time, and is also lichenized. Recent collections ofNigropuncta rugulosa D. Hawksw. from Austria and Italy also show that this species is lichenized rather than parasymbiotic. In all five cases the fungal hyphae of the conidiogenous structures are continuous with those in intimate contact with cells of the algal partners and the biological relationship appears to be mutualistic giving rise to stable crustose lichen thalli.  相似文献   

20.
Creeping thistle, Cirsium arvense (L.) Scop. (Asteraceae), is one of the most serious weeds in ecological compensation areas (within-field or border refugia) in Europe. Since conventional weed control measures are restricted in compensation areas, augmenting indigenous agents for biological control of the weed may be a feasible alternative. In this paper, we studied the effect of density of the shield beetle, Cassida rubiginosa Muller (Coleoptera, Chrysomelidae), and two vegetation types typical for ecological compensation areas, on the performance of creeping thistle plants in an open field experiment. Early-season larval feeding had no measurable effect on creeping thistle growth, while late-season feeding significantly reduced shoot growth. These findings were attributed to higher feeding rates of the herbivores at higher ambient temperatures late in the season. Defoliation had a strong effect on the above-ground performance of C. arvense plants, but not on the below-ground performance. In contrast, the plant community affected all below-ground performance parameters measured, but only some of the above-ground performance parameters of creeping thistle. A combination of high levels of plant competition and herbivory by C. rubiginosa larvae led to 50% mortality in C. arvense plants during the growing season. We conclude that augmentation of indigenous herbivores of C. arvense in combination with breaking up the root system by tillage and the establishment of a highly competitive plant community of beneficial herbs may be a feasible way to control this problematic weed in ecological compensation areas.  相似文献   

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