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1.
An outbreak of larvae and adults of a devastating moth was noted to be causing severe damage in tomato grown in greenhouses at Khartoum State, Sudan during June 2010. Symptoms included foliage mining and leaves drying. Photographs of symptoms and larvae and adults of the pest (and subsequently specimens) were sent to Russell IPM, UK and the Finnish Museum of Natural History for identification. The pest was identified as Tuta absoluta (Meyrick), (Lepidoptera: Gelechiidae). This is the first official record of T. absoluta in Sudan, based on surveys in tomato production areas in Khartoum, Gezira, Red Sea and North Kordofan States and eggplant and potato in Khartoum State. Severe yield loss due to the serious feeding damage on foliage and fruits infestation was reported on tomato and eggplant fields at Khartoum State. 相似文献
2.
H. Schmutterer 《Anzeiger für Sch?dlingskunde》1998,71(2):36-38
In 1996 and 1997, several pests and a semi-parasitic plant species were identified as pests of the neem tree in Kenya, East
Africa. Some damage was caused by a gall mite (Phyllocoptes sp.) at Mbita Point in western Kenya in a nursery and on older plants. The potentially dangerous scale insectAonidiella orientalis was widespread in western Kenya but not harmful for the time being. In coastal areas the semi-parasiteCassytha filiformis was very common. This plant is able to kill mature trees growing under unfavourable conditions. As in West Africa, fruit
bats likeEpomophorus wahlbergi were useful due to their feeding activity on the pulp of ripe neem fruit, making consequently depulping (by man) was unnecessary. 相似文献
3.
M. E. E. Mahmoud S. A. Mohamed F. M. Khamis M. A. I. Basher S. Ekesi 《EPPO Bulletin》2019,49(2):359-363
Bactrocera zonata is an alien fruit fly which was introduced into Sudan in 2012 and spread throughout the country, severely hampering the production and export of fruit and vegetable crops. Cataloguing indigenous natural enemies of pests, especially parasitoids, is key to successful biological control programmes, to mitigate damage and decrease reliance on insecticides. This study was conducted to determine the parasitoids of B. zonata in two orchards in Gezira State, Sudan from November 2015 to May 2016 and from February to December, 2016 and to determine their role in natural control of the pest. Three parasitoids emerged from puparia of B. zonata, these were: Tetrastichus giffardianus Silvestri (Eulophidae), an Aganaspis sp. (Figitidae: Eucoilinae) and a Psyttalia sp. (Braconidae Opiinae). Tetrastichus giffardianus was the most numerous parasitoid throughout the study period. The mean percentages of B. zonata from guava fruits that were parasitized by T. giffardianus for the whole study period were 13.7% and 13.2% with 3.1 ± 0.3 and 2.8 ± 2.4 parasitoids per puparium at Fadasi and Gazirat Elfil sites respectively. Data on the temporal abundance of T. giffardianus is presented. Strenuous efforts should be considered to involve the reported natural enemies of B. zonata in integrated management programmes for fruit flies in Sudan. 相似文献
4.
Journal of Plant Diseases and Protection - Greenhouse experiments were conducted at Khartoum (Sudan) with the aphid predator Hippodamia variegata, two botanical and one synthetic insecticides: neem... 相似文献
5.
Gaafer A. El-Zorgani 《Pest management science》1976,7(2):150-152
Twenty-eight specimens representing five types of fish and five types of birds from the Gezira Research Farm, Wad Medani, Sudan, were analysed for residues of organochlorine insecticides. All fish muscle samples were found to contain pp′-DDE, pp′-TDE and pp′-DDT in total concentrations ranging from 0.27 to 16.0 mg/kg. In addition to DDT-type residues, dieldrin (HEOD) was also found in the majority of bird samples. Concentrations in bird breast muscle ranged from 0.07 to 5.5 mg/kg. When bird liver samples were examined they were found to contain higher residues than the breast muscle in nearly all cases. 相似文献
6.
R. J. V. Joyce 《国际虫害防治杂志》2013,59(1):62-70
Abstract Mobility results in movement of insects from their birth place (emigration) to another site (immigration). The scale, both in time and in space, on which such migration occurs may determine rates of increase or decrease in numbers in a fixed geographical area or plot. This is self evident in the case of mobile insects, such as locusts. Other documented examples include the spruce budworm in Canada and the Queensland fruit fly. In the Sudan Gezira the distribution of the major insect pest of cotton, Heliothis armigera Hb., was found to conform to a common temporal pattern over probably some thousands of square kilometres, and other major pests, Empoasca libyca de Berg and Bemisia tabaci Gen., are considered to be similarly distributed, suggesting that their occurrence in damaging numbers may be dominated by transport and concentration by major windfields rather than by natality and mortality within a field or area. This posibility was investigated using a Pilatus Turbo-Porter aircraft fitted with Doppler Navigator equipment and an insect collecting net, and densities of flying insects monitored by a ground-based Marine-type Radar. The results of this study will make it possible to determine the spatial extent of a threatening population and the time during which that population is present, so that control action may be taken on a commensurate scale. Such matching of scale of operations to insect mobility is of particular importance when repeated invasions occur during periods of rapid crop growth, because it enables non-persistent insecticides to be employed, thus providing potentially better utilisation of parasites and predators than can be achieved by maintaining the crop as an environment lethal to insects. These procedures, connoted ‘synoptic survey’ and ‘synchronous control’, require that the control is applied on a scale determined by pest mobility rather than by the boundaries of fields or other artificial constraints. Evidence is accumulating regarding the importance of insect mobility, in particular adaptive dispersal, in population dynamics and this may require re-assessment of farmer and government responsibilities in crop protection. 相似文献
7.
Chemical control of the intermediate hosts of schistosomiasis, based on copper sulphate, has been practised in the Sudan Gezira since 1956. A continued use of the more recent trifenmorph blanket-treatments raises the question of eventual resistance to this molluscicide. Two collections of Bulinus truncatus (Audouin), from a treated and an untreated area of the Gezira, have therefore been subjected to laboratory rearing, bioassay and measurement of the rate of uptake of the chemical into the snail. A difference in susceptibility could be shown and this has been tentatively attributed to the rather more marked difference, in penetration rate of the molluscicide, between the two groups of snails. 相似文献
8.
Margosine-0®, a commercial preparation of neem seed extract, was tested for its effects as a toxicant, growth inhibitor, or repellent against six species of cockroaches —Blatta orientalis L.,Blattella germanica (L.),Byrsotria fumigata Guérin-Méneville,Gromphadorhina portentosa (Schaum),Periplaneta americana (L.), andSupella longipalpa (F.) (Orthoptera: Blaberidae, Blattidae, and Blattel-lidae). Last-instar nymphs of these species fed Lab-Chow® pellets impregnated with neem extract at a rate of 0.5 ml/pellet showed increased mortality and retarded development. All lst-instar nymphs ofB, orientalis, B. germanica andS. longipalpa died after consuming treated Lab-Chow pellets. Topical application of 2 μl of Margosine-0 to the abdomens of last-instarB. orientalis nymphs, as well as injection of 0.5 μl, resulted in reduction of growth and increased mortality. Placing lst-instarB. orientalis nymphs on a surface treated with the neem extract had no notable effect. In a choice test,P. americana adults immediately preferred the pellets treated with 0.5 ml of neem extract, but pint cardboard cartons treated with 1.5 ml extract repelled them. 相似文献
9.
Factors influencing the weed flora in the Gezira Scheme, Sudan 总被引：1，自引：0，他引：1
Agriculture plays a major role in the economic and social development of Sudan. The most important agricultural area in Sudan is the irrigated Gezira Agricultural Scheme (GAS), which takes water from the Sennar Dam on the Blue Nile. This study investigated weed communities in relation to geographical location and crop rotation in 2000 and 2001. Five agricultural units were sampled from the central sector of the GAS; within each unit we surveyed weed communities in different phases of the crop rotation: cotton, groundnuts, sorghum, and a fallow. The distribution of weed species showed some similarities in the 2 years sampled, with most species being found in all agricultural units but their relative proportions differed. Broad-leaved weeds were dominant, suggesting that herbicides selected for weed control in the Gezira scheme need to be effective against this group of species. Agricultural unit and crop type affected weed communities in both years. The weed flora was largest in cotton, intermediate in groundnuts and sorghum, and smallest in the fallow. Although most weeds were found in all agricultural units; however, their relative abundances differed greatly, either as a result of differences in management between the units, or some other spatial effect. As such, weed control programmes need to be tailored at the agricultural unit scale. 相似文献
10.
GEORGE I. GHOBRIAL 《Weed Research》1981,21(5):201-204
Large losses in grain yields due to weed competition were found in studies conducted in irrigated dry seeded rice at Gezira Research Station, Sudan. These losses could exceed 50%. Weed competition lowered panicle number per unit area by 37%, number of filled grains per panicle by 13%, and weight of 1000 grains by 4%. Tillering was the critical growth phase most affected by weed competition. Grain yields were increased as number of hand weedings increased. The best yield (4.1 t/ha) was obtained from 3–4 weedings carried out at 15, 30, 45 and 60 days after rice emergence. Oxadiazon (0.5 kg/ha) gave good residual weed control of the dominant weed species, Phyllanthus niruri L., Leucas urticifolia L., Heliotropium F.W.Andr. and Echinochloa colona (L.) Link, for 6–7 weeks. The combination with continuous flooding from 6 weeks after rice emergence gave excellent weed control during the entire season, and comparable or even better yields than frequently weeded rice. 相似文献
11.
Hairy root cultures have been derived from neem (Azadirachta indica A Juss, Family Meliacceae) using Agrobacterium rhizogenes and have been studied for the production of compounds with antifeedant effects on insects. Six-week-old hairy root cultures were extracted, and HPLC yielded fractions ranging from polar to non-polar compounds. High antifeedancy levels against the desert locust were observed in fractions(F) 2, 3 and 4 whilst F1 and F5 were not significantly antifeedant. Interestingly F3 did not contain any of the well-known neem chemicals while F2 contained azadirachtin and 3-tigloylazadirachtol and F4 nimbin and salannin. © 1999 Society of Chemical Industry 相似文献
12.
Serap Mutun 《Phytoparasitica》2009,37(1):65-66
An invasive Tingidae, the platanus lace bug Corythucha ciliata (Say, 1832) (Hemiptera: Tingidae), which specializes on Platanus spp., was found for the first time in Turkey in 2007; it was recorded from a 120 km2 area in the northwestern part of the country. Infestations occurred in an area between Taşkesti and Abant in Bolu Province,
which is located near major cities and two main motorways. The pest species is newly spreading in Turkey, causing noticeable
damage to Platanus orientalis trees. 相似文献
13.
Mikdat Doğanlar Abdurrahman Yiğit Yair Ben-Dov İlhan Üremiş Mehmet Arslan 《Phytoparasitica》2010,38(3):231-236
The scale insects Acanthomytilus sacchari (Hall) and Duplachionaspis erianthi Borchsenius (Hemiptera, Diaspididae) are newly recorded as indigenous insects from Turkey. Both A. sacchari and D. erianthi were found to feed only on rhizomes of Johnsongrass. A field study was conducted to determine host ranges and feeding effects
of these scale insects on Johnsongrass, Sorghum halepense (L.) Pers. No feeding of these species was observed on Zea mays L. (maize), Sorghum sudanense Staph. (sorghum), Aegilops triuncialis L. (barbed goatgrass), Avena fatua L. (wild oat), A. sterilis (sterile oat), Bromus tectorum L. (downy brome), Cynodon dactylon (L.) Pers. (bermudagrass), Phragmites australis (Cav.) Trin. ex Steudel (common reed), Poa bulbosa L. (bulbous bluegrass), or Secale montanum Guss. (wild rye). The mean infestation rates of the scale insects on Johnsongrass in southeastern Anatolia were 11.47% and
1.64% for A. sacchari and D. erianthi, respectively. Further investigations are required to clarify their biology and damage to Johnsongrass under field conditions. 相似文献
14.
Transmission of ‘Candidatus Phytoplasma pyri’ by naturally infected Cacopsylla pyri to peach,an approach to the epidemiology of peach yellow leaf roll (PYLR) in Spain 
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下载免费PDF全文 Peach orchards in the northeast of Spain were severely affected in 2012 by a previously unreported disease in this area. The symptoms included early reddening, leaf curling, decline, abnormal fruits, and in some cases death of the peach trees. All the infected peach samples were positive for ‘Candidatus Phytoplasma pyri’, but none were infected by the ‘Ca. Phytoplasma prunorum’. In this work, potential vectors able to transmit ‘Ca. Phytoplasma pyri’ from pear to peach and between peach trees were studied and their infective potential was analysed at different times of the year. Transmission trials of the phytoplasma with potential vectors to an artificial feeding medium for insects and to healthy peach trees were conducted. Additionally, isolated phytoplasmas were genetically characterized to determine which isolates were able to infect peach trees. Results showed that the only insect species captured inside peach plots that was a carrier of the ‘Ca. Phytoplasma pyri’ phytoplasma was Cacopsylla pyri. Other insect species captured and known to be phytoplasma transmitters were present in very low numbers, and were not infected with ‘Ca. Phytoplasma pyri’ phytoplasma. A total of 1928 individuals of C. pyri were captured in the peach orchards, of which around 49% were phytoplasma carriers. All the peach trees exposed to C. pyri in 2014, and 65% in 2015, were infected by ‘Ca. Phytoplasma pyri’ 1 year after exposure, showing that this species is able to transmit the phytoplasma to peach. Molecular characterization showed that some genotypes are preferentially determined in peach. 相似文献
15.
R. Singh A. Kalra B. S. Ravish S. Divya T. N. Parameswaran K. V. N. S. Srinivas D. J. Bagyaraj 《Plant pathology》2012,61(4):700-708
Based on earlier results obtained in pot experiments, 2‐year field experiments were conducted with five bioinoculants and neem cake under organic field conditions (with vermicompost as a nutritional supplement) to evaluate their potential to control root‐rot and wilt (a complex problem involving Fusarium chlamydosporum and Ralstonia solanacearum) of the medicinal plant Coleus forskohlii. Plants treated with arbuscular mycorrhizal fungus (Glomus fasciculatum), neem cake or Pseudomonas fluorescens showed significantly increased plant height (15–31%), plant spread (25–33%), number of branches (63–67%) and dry root (129–200%) yields, and reduced disease incidence (47–50%) compared to controls. Increases in yields were reflected by increases in N (51–81%), P (17–76%) and K (44–74%) uptake. The forskolin content of the roots was found not to be affected by any of the bioinoculants, but forskolin yield (calculated) was increased significantly by treatment with G. fasciculatum (227%), neem cake (222%) or P. fluorescens (159%). 相似文献
16.
Von O. Eichhorn 《Anzeiger für Sch?dlingskunde》2000,73(1):13-16
In the East Pontic mountains at Giresun (Black Sea shore) three species of the genus Dreyfusia have been established: D. nordmannianae Eckst. and D. prelli Grosm. on Abies nordmanniana Link. and Picea orientalis Link. and Dreyfusia nov. spec. on A. nordmanniana. The latter species, earlier known from Greece and the Balkans, but not yet described is most probably unholocyctic on fir.In the Zigana mountains between Trabzon and Gümüsane a species producing plenty galls on young P. orientalis trees and closely resembling D. merkeri Eichh. has been observed. Further investigations are necessary to evaluate whether or not it lives unholocyclic on spruce.In the West Pontic mountains near Bolu D. nordmannianae was intensively studied in twig infestations on A. bornmülleriana Mattf. The pattern of attack differs greatly from the one experienced in central Europe in that almost exclusively the current year's shoots are attacked whereas the leader and the older twig axis remain free of attack. In Europe all parts of the trees are colonized.Considering the known facts about generation- and morph sequences, morph determination and phenological behaviour of D. nordmannianae the characteristics of their population dynamics in Turkey and the interactions of the curious mode of attack and the extraordinary efficiency of their special predators have been completely evaluated. 相似文献
17.
Factors affecting the activity of GR7 in stimulating germination of Striga hermonthica (Del.) Benth.
Experiments with the alkaline heavy clays of the Sudan Gezira showed that when the strigol analogue GR7 was applied to moist soil prior to subjecting Striga hermonthica seeds to moist conditions (‘conditioning’) for 7–14 days, there was no significant increase in germination. Conditioning of seeds in soils treated with GR7 had an adverse effect on the responsiveness of seeds when GR7 was added again after conditioning. Under ideal conditions, when GR7 was applied to conditioned seeds in moist soil, up to 75% germination could be induced by 2.0 kg/ha incorporated to 2–3 cm depth. Residual activity of GR7 persisted in air-dry soil, but at 50% moisture there was complete loss within 1 day. However, when conditioned seeds were put into the soil immediately after GR7 application its activity increased with increasing soil moisture. 相似文献
18.
Systemic injection of neem (azadirachtin) was tested in the control of horse chestnut leafminer,Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae), a pest of horse chestnut trees (Aesculus hippocastanum L.: Hippocastanaceae). Three concentrations, 0.08, 0.15 and 0.25 g of active ingredient (a.i.) per cm of diameter at breast
height (dbh), provided long-lasting insecticidal activity. The 0.15 and 0.25 g a.i. concentrations resulted in 100% pupae
reduction in all generations; the 0.08 g a.i. concentration was effective against the horse chestnut leafminer for at least
23 weeks and led to 70–80% pupae reduction. Treated trees did not lose their leaves before winter. Neem applicationvia injection is cheap, with no environmental hazards, and thus this treatment is recommended for the control ofC. ohridella in horse chestnut trees.
http://www.phytoparasitica.org posting Dec. 19, 2004. 相似文献
19.
The aphids Aphis craccivora Koch attack country bean Lablab purpureus L. both in its vegetative and reproductive stages and cause severe damage. To develop an integrated management of aphid powders of black pepper, chili, turmeric, and coriander; oils of mahogany, neem, and eucalyptus; aqueous extracts of neem, basil, and garlic leaves; and water were evaluated in field conditions. The treatments were applied at 7?day intervals and aphid abundance per inflorescence was counted at 24, 48, and 72?h after treatment. All the plant materials reduced aphid abundance and flower infestation, ensuring a higher yield with larger and heavier pods. The neem oil treatment had the lowest abundance of aphid and consequently produced the highest marketable and gross yields. Predatory insects were abundant in the field, but their populations were lower in the treatments than the control. An economic analysis indicated that the highest gross return, net return, adjusted net return, and benefit-cost ratio were obtained from the mahogany oil treatment. The plant materials have insecticidal potential against aphids, and the oils of mahogany and neem showed better performances. 相似文献
20.
Recent disease surveys in the Western Cape province of South Africa have revealed a previously unknown and serious stem canker disease on native Rapanea melanophloeos (Myrsinaceae, Ericales) trees. Cankers commonly result in the death of branches or entire stems. Fruiting structures typical of fungi in the Cryphonectriaceae were observed on the surfaces of cankers. In this study, the fungus was identified and its pathogenicity to R. melanophloeos was tested. Multigene phylogenetic analyses based on DNA sequences of the partial LSU gene, ITS region of the nuclear ribosomal DNA gene and two regions of the β‐tubulin (BT) gene, showed that the fungus represents a formerly undescribed genus and species in the Cryphonectriaceae. The fungus was also morphologically distinct from other genera in this family. Inoculation trials showed that the fungus described here as Immersiporthe knoxdaviesiana gen. et sp. nov. is an aggressive pathogen of R. melanophloeos trees. 相似文献