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31.
Lychees were surveyed in Queensland, Australia and in Guangdong Province and Hainan Island China, for natural enemies of the lychee erinose mite,Aceria litchii (Keifer), one of the most serious pests of lychee in Australia. A guild of seventeen predators, including ten species of phytoseiid mites, was associated with lychee erinose in Queensland. Six other predaceous mite species and a cecidomyiid larva,Arthrocnodax sp. were also part of the complex. Despite the apparent predation of most of the seventeen species recorded in Queensland onA. litchii, the pest continues to cause major problems. In China, whereA. litchii is a relatively minor pest, nine phytoseiid species were collected in lychee orchards. The value of introducing additional predators to Australia, especially from China, is discussed. 相似文献
32.
F. N. Zaki M. F. El-Shaarawy N. A. Farag 《Archives Of Phytopathology And Plant Protection》2013,46(5):328-332
Abstract The biological effect of plant extracts on the two predators C. carnea and C. undecimpunctata was studied in the laboratory. Treated B. brassicae was offered to the newly hatched larvae of the two predators. The rate of prey consumption and duration of the larval instars of the two predators were slightly affected as a result of the treatments of the plant extracts. Adults of the aphid parasite D. Rapae and the whitefly parasite E. Mundus were exposed to the plant extracts via feeding on treated honey droplets or parasitized treated hosts. Mortality percentages of D. Rapae fed on honey contaminated with plant extracts were 50 and 80% for extracts of Melia fruits in ethanol and in petroleum ether, respectively. Mortalities in parasites developed in hosts treated with plant extracts of Neem fruits in ethanol and Melia flowers in petroleum ether in were 33.3 and 81.5%, respectively. Similar results were obtained when E. Mundus received the same treatments of the plant extracts. 相似文献
33.
JUN GONG SHAN GAO DAVID McL. ROBERTS KHALED A.S. AL‐RASHEID WEIBO SONG 《The Journal of eukaryotic microbiology》2008,55(6):492-500
ABSTRACT. A new marine cyrtophorian ciliate Trichopodiella faurei n. sp., which belongs to the order Dysteriida, family Hartmannulidae, was investigated at the morphological and molecular levels. A combination of morphological features of the organism including the oval body shape, 2–3 contractile vacuoles, 22–28 nematodesmal rods in the cytopharyngeal basket, and 31–39 somatic kineties, distinguishes it from all other known congeners. In reconstructed small subunit (SSU) rRNA phylogenies, T. faurei groups with Isochona, a representative genus of the subclass Chonotrichia. The similarity of the infraciliature between hartmannulids and several chonotrichian examples also suggests that these taxa should be closely related. A new S943 intron belonging to group IC1 was identified in the SSU rRNA gene of this species. This intron is phylogenetically related to the S891 introns previously found in the suctorians Acineta sp. and Tokophrya lemnarum, and their internal guide sequences share four nucleotides, indicating that these introns were vertically inherited from a common phyllopharyngean ancestor and that reverse splicing might have been involved in the transposition. 相似文献
34.
ESMATMOHAMEDHEGAZI ANNETTEHERZ SHERIFHASSAN ESSAMAGAMY WEDADKHAFAGI SANIASHWEIL AHMEDZAITUN SAFAAMOSTAFA MOHAMEDHAFEZ AHMEDEL-SHAZLY SOMAIAEL-SAID LAMIAABO-ABDALA NOHAKHAMIS SAMIAEL-KEMNY 《Insect Science》2005,12(3):185-192
A survey of two-year studies (2001-2003) was carried out in two olive groves sited at two representative olive growing areas, namely Paradise Park (arid area) and Burg E1-Arab farm (semi-arid area) to monitor the frequency of endemic Trichogramma species on olive moth (Prays oleae) and jasmine moth (Palpita unionalis). The suspended host bait traps were found to be a more practical and effective tool for collecting Trichogramma wasps than the attached ones. Four naturally occurring Trichogramma species were collected for the first time in Egypt from the olive groves, where releases have never been conducted. T.bourarachae was collected exclusively from Burg El-Arab farm. It seems that this wasp species adapts well to the semi-arid area. Three species, namely T. cordubensis, T. nr.pretiosum and T. cacociae were isolated from Paradise Park farm. All of these wasps were also bred from naturally parasitized host eggs during favorable and even at unfavorable temperature conditions of June-August. However, these endemic species did not occur naturally in sufficient numbers to keep the pest populations from reaching damaging levels.The excessive usage of insecticides and the oophagous predators (e.g., ants and lacewing larvae) are some factors that affect the performance of Trichogramma wasps in olive farms.The presence of warm weather wasp strains suggests the existence of well-adapted wasp species or swains which may be appropriate candidates for the control of target pests in olive groves. Additional study is required to determine the best “habitat-specific” species/strains of Trichogramma for augmentative release of naturally occurring wasps and to incorporate them into integrated pest management programs. Efforts should be made to conserve these endemic species from oophagous predators, hot weather and insecticides.The olive and jasmine moth-larvae and pupae found under tree canopies were bred and emerged parasitoids were listed. 相似文献
35.
Protozoan epibionts on Mysis relicta Loven, 1862 (Crustacea, Mysidacea) from Lake Lüšiai (Lithuania)
Gregorio Fernandez-Leborans 《Acta zoologica》2004,85(2):101-112
Protozoan epibionts were found on specimens of the mysid Mysis relicta collected in Lake Lü?iai (Lithuania). These protozoans belong to three genera of ciliates: Vorticella, Dendrosoma and Tokophrya, and were located on the antennae, carapace, appendages and abdomen of the basibiont. The ciliates of the genus Vorticella had a bell‐shaped body, with concave‐type striations and a very long contractile stalk. The stalk joined the body via a truncated and overlapping zone. The macronucleus was J‐shaped, and the contractile vacuole was anterolateral. Only one ciliate species of Vorticella has been found on mysids, although on species other than M. relicta, and this is therefore the first record of Vorticella on M. relicta, and the second on the order Mysidacea. The ciliates of the genus Dendrosoma had an irregular body directly attached to the substrate. Finger‐like actinophores arose from the body, with a bundle of tentacles at their ends. The macronucleus ramified into branches that followed the actinophores. These ciliates were included in the species D. astaci. The presence of this ciliate represents the first record of this genus on Mysis relicta. The ciliates of the genus Tokophrya had a pyramidal body, the apical surface of which showed two conspicuous actinophores, with a short, longitudinally striated stalk joining to the body via a narrow unstriated band. The macronucleus was spherical or ovoid, centrally located, and there was an apical contractile vacuole. Only one previous study has referred to the presence of this genus on Mysis relicta, and the data contained in it were compared with those of the present study. The biometrical data and taxonomical position of the ciliate epibionts was considered. 相似文献
36.
B. A. DEHORITY 《The Journal of eukaryotic microbiology》1974,21(1):26-32
Total numbers, generic distribution and percentage species distribution were determined for the ciliate protozoa in rumen contents obtained from Alaskan moose (Alces americana), musk-ox (Ovibos moschatus) and Dall mountain sheep (Ovis dalli). The musk-ox has a fauna somewhat similar to that previously observed in reindeer and caribou. In contrast, only protozoa in the genus Entodinium were observed in moose, while Dall mountain sheep have a fauna unique among Alaskan ruminants studied to date. Other than Entodinium exiguum which was common to all animals, only 2 additional species of Entodinium, observed in the moose and musk-ox, occurred in more than one animal species. Four new species of protozoa are described, Entodinium dalli sp.n., Entodinium constrictum sp.n. and Polyplastron alaskum sp.n. from the Dall mountain sheep and Entodinium alces sp.n. from moose. 相似文献
37.
Nyctemera annulata Boisduval was reared in the laboratory at 26±1°C and 50 ±5% RH on a host plant, ragwort (Senecio jacoboea L.), and on an artificial diet. On ragwort the average life cycle of 34 days embraced a larval period of 24 days, with up to 6 larval instars, and a pupal period of 9–11 days, depending on whether pupation occurred at the 5th or 6th instar. On the artificial diet the larval period of 56 days, involving up to 10 instars, was followed by a pupal period of 9 days, for an average life cycle of 65 days. 相似文献
38.
于2011年春季(5月)和秋季(11月)在东海陆架区进行浮游纤毛虫丰度和生物量的调查.春季和秋季纤毛虫的平均丰度分别为(614±861)和(934±809) ind·L-1,平均生物量分别为(1.70±3.91)和(0.93±0.99) μg C·L-1.表层纤毛虫丰度和生物量的高值区春季主要分布在近岸及远岸海区,秋季主要分布在远岸海区.春季纤毛虫的丰度和生物量在水体上层较高;秋季纤毛虫主要分布在水体上层,有时在水体底层也会出现丰度和生物量的高值.春季无壳纤毛虫群落的粒级较大,秋季较小.砂壳纤毛虫占纤毛虫丰度的平均比例春季和秋季分别为(26.9±34.3)%和(44.9±25.2)%.两个季节共鉴定出砂壳纤毛虫27属52种,春季丰度较大的种为原始筒壳虫、橄榄领细壳虫及筒状拟铃虫,秋季丰度较大的种为原始筒壳虫、小领细壳虫及矮小拟铃虫.纤毛虫丰度与温度、叶绿素a(Chl a)浓度呈显著正相关.砂壳纤毛虫丰度与盐度呈显著负相关,群落结构变化与温度显著相关. 相似文献
39.
Rui Lourenço Sara Maria Santos João Eduardo Rabaça Vincenzo Penteriani 《Population Ecology》2011,53(1):175-185
Predatory interactions among top predators, like superpredation or intraguild predation (IGP), can influence community structure.
Diurnal raptors occupy high trophic levels in terrestrial food webs, and thus can regulate the presence of mesopredators.
We studied superpredation (the killing and eating of another predator) in four large European raptors. We gathered 121 dietary
studies, totalling 161,456 prey for the Goshawk Accipiter gentilis L., Golden Eagle Aquila chrysaetos L., Bonelli’s Eagle Aquila fasciata Vieillot, and Eagle Owl Bubo bubo L. Results showed that superpredation: (1) is a widespread interaction in large raptors, but it can vary according to the
top predator species; (2) is not an important energetic resource for large raptors, but rather seems mostly related to diet
diversification when the main prey decreases; (3) is spatially clustered reflecting habitat heterogeneity, but shows no temporal
or large-scale spatial trends; and (4) it is associated with lower breeding success of the top predator species. These findings
support the food stress hypothesis as the main driving force behind increases in superpredation and IGP in raptors, with the
decrease in breeding performance as a side effect. Superpredation by large raptors deserves future research to understand
its effects on mesopredators, because on one hand it might contribute to promote biodiversity, while on the other hand, it
can sometimes represent an additional risk for small populations of endangered mesopredators. 相似文献
40.
《European journal of protistology》2014,50(5):496-508
Three species of Diophrys, D. peculiaris nov. spec., D. cf. scutum and D. oligothrix, isolated from the New Nagasaki Fishing Port, Nagasaki, Japan, were investigated using live observation and protargol impregnation. Diophrys peculiaris nov. spec. can be recognized by having two characteristic clusters of rod-like structures and two groups of dikinetids located on anterior dorsal portion of cell. Morphogenetic data show that this part of the life cycle basically proceeds as in congeners, except for the formation of dikinetids under the rod-like structures. In the opisthe, the origin of dikinetids under the rod-like structures is still unknown, but the old dikinetids under the rod-like structures may be retained by the proter. The Japanese population of Diophrys cf. scutum resembles other populations of D. scutum well except for moniliform macronuclear segments. Our populations of D. oligothrix correspond well with other populations in terms of general morphology and ciliary pattern, in particular the continuous dorsal kineties with loosely arranged cilia. 相似文献