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[en] Carnivorous plants use insects not only as prey, but also as pollinators. Whereas outcrossing carnivorous plants are known to avoid trapping pollinators, selfing carnivorous plants may capture the pollinators as prey. Here, we provide evidence that two selfing carnivorous plant species with short flower-trap separation, Drosera makinoi (white-colored flowers) and D. toyoakensis (pink-colored flowers), caught some major pollinator species belonging to Diptera and Hymenoptera: four out of five species in D. makinoi and one out of six species in D. toyoakensis. We also tested the function of flowers to attract pollinator or prey insects by experimentally removing Drosera flowers. Flower removal did not significantly affect the number of trapped insects. On the other hand, the removal of flowers of co-flowering neighbor plants, Eriocaulon decemflorum for D. makinoi and Lysimachia fortunei for D. toyoakensis, significantly decreased the number of trapped insects. This finding suggests an exploitative relationship between Drosera spp. and co-flowering species.
[en] Plants produce a plethora of chemical compounds that can be used for various applications. Philippines is one of the mega-diverse country in the world in terms of its fauna na flora. Today different plant sepcies are being tapped as source of natural products that can be used to develop greener solutions vis-a-vis synthetic ones. This study used traditional fruit bearing fauna, Annona squamosa L. and Mangifera altissima B. to screen for biological activity against the tropical cocount pest, Brontispa longissima G. Organic preparations via reduced vacuo from seeds of these plant species were evaluated. In vitro-assays performed revealed that the selected organic preparations of M. altissima and A. squamosa were comparable to synthetic formulation. These were further evaluated under stimulated conditions at the screening facility of the Philippine Coconut Authority -Albay Research Center. Organic formulations have also shown less adverse biological effects on non-target species such as parasitoid, Tetrastichus brontispae F. (Hymenoptera: Eulophidae). Hence, data from plants with potential for applications in agriculture and other key sectors of the country. (author)
[en] The preimaginal stages of T. peregrina are described. The egg displays a sculptured chorion, which is found only on those deposited externally. The immature larvae are characterized by their peculiarities in (a) a setose ring on the thoracic and abdominal segments, (b) an anal notch and (c) size and the sensory structures of the head capsule. The final instar is described and illustrated. Morphological structures of diagnostic value are discussed. The most salient character shown by the mature larva of this species lies in the epistoma, which is complete. (author)
[es]Se describen las fases de huevo y larva de T. peregrina. El huevo, como es caracteristico en los que se depositan externamente, presenta un corion ornamentado. Las larvas inmaduras exhiben peculiaridades en (a) el anillo setoso de los segmentos toracicos y abdominales, (b) la escotadura anal y (c) el tamano, y estructuras sensoriales, de la capsula cefalica. El estado de caracter mas sobresaliente presentado por la larva madura de esta especie radica en la presencia de un epistoma totalmente diferenciado. (author)
[en] Field trials were conducted in the Research Area, Directorate of Sugarcane, Ayub Agricultural Research Institute, Faisalabad to study he physio-morphic characters of sugarcane resistance to the sucking pest Pyrilla perpusilla. Twenty genotypes of sugarcane were tested for their resistance susceptibility against P. perpusilla, as a preliminary screening experiment, during 2006. Based on the population-density count, 3 genotypes, viz., HSF- 240, CPF-243 and S-2002-US-114 showing resistance responses, 3 genotypes viz. CPHS-35, S-2003-US-394 and S-2003-US-623 showing susceptible trends and 3 genotypes viz. S-2003-US-809, S-2002-US-140 and S- 2002-US-104 exerting intermediate trends against the pest under test were selected for the final screening trials during 2007.The genotype S-2003-US-623, was found to be comparatively susceptible; whereas, HSF-240, showed resistance responses. The leaf-width and cane length showed a positive and significant correlation whereas the leaf-spine density had a significant negative effect with pest-population. The Leaf-length and Cane-Diameter did not show a significant correlation with the pest population. (author)
[en] Lysiphlebus testaceipes (Cresson) has a broad aphid host range; however the quality of these preys may interfere in its biological feature. This study aimed to evaluate the quality of three Macrosiphini, Brevicoryne brassicae (L.), Lipaphis erysimi (Kaltenbach) and Myzus persicae (Sulzer), and three Aphidini Schizaphis graminum (Rondani) Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover as hosts to L. testaceipes and to determine the relation possible of host preference, of size and quality of the host. The tests were carried out in climatic chamber at 25 ± 1 deg C, RH 70 ± 10% and 12h photophase. The parasitoid did not oviposite in B. brassicae and L. erysimi, while the other species were nutritionally suitable to the parasitoid. L. testaceipes showed preference for aphids from tribe Aphidini and these hosts presented better quality to the parasitoid when compared to Macrosiphini. Interactions among size, preference and quality between the Aphidini were found. L. testaceipes showed preference (parasitism rate 76.7%) for R. maidis, the bigger host (hind tibia with 0.281 mm). This host provided bigger size (hind tibia with 0.49 mm) and higher emergence rate (95.6%) to the parasitoid when compared to A. gossypii (parasitism rate of 55.7%). Also the smaller host A. gossypii (0.266 mm) provided smaller size hind tibia (0.45 mm) and higher mortality of the parasitoid (emergence rate 72.1%). However, the development time was shorter and the longevity was higher in A. gossypii (6.3 and 5.4 days, respectively) when compared to the host R. maidis (6.7 and 3.8 days, respectively), and not been related to host size. (author)
[en] Bag worms (Lepidoptera: Psychidae) are one of the important leaf-eating pests of oil palm in Malaysia and Indonesia. Crop losses, due to the extensive defoliation by a serious bag worm attack are inevitable. The establishment and propagation of the bag worm's parasitoids, depend very much on species of flowering plants as sources of nectar. Cassia cobanensis, was proven suitable due to its attractiveness to most bag worm parasitoids. A study to assess the diversity of bag worm's natural enemies (hymenopterous parasitoids and reduuvid predatory bugs) on the C. cobanensis plant and within the undergrowth of the oil palm planting block was evaluated by sweep net and sticky trap sampling. Environmental parameters such as light intensity, temperature and relative humidity were also recorded during the sampling to determine their possible range of influence towards the activity of the insect natural enemies. The Shannon-Wiener diversity index of insect natural enemies occurring on the C. cobanensis plant was 2.32. Among the dominant parasitoids observed on C. cobanensis plants are chalcids (Brachymeria lugubris and Brachymeria carinata) and braconids (Dolichogenidea metesae and Apanteles aluella), besides the reduuvid predator, Cosmolestes picticeps. In contrast, within the oil palm planting block, the undergrowth within the non-harvesting path only recorded a much lower diversity index of 1.09 and 1.12 each, in a block with C. cobanensis at the roadside and without, respectively. However, C. picticeps was shown to be much more dominant within both oil palm planting blocks, up to two- to three-fold, with much lesser numbers of hymenopterous parasitoids (less than five individuals). This indicates the important contribution of C. cobanensis plant towards enriching the diversity of the parasitoids, which are normally not found within the oil palm block, due to much less intense sunlight. In terms of insect activity, they are significantly more active in the moderate or medium light intensities (<8000 fc), medium humidity levels (50 - 69 %) and medium temperatures (30 - 34 degree Celsius). (author)
[en] Full text: We determined the acceptability and suitability of eggs of Cryptophlebia leucotreta (Meyrick) to parasitisation by Trichogrammatoidea cryptophlebiae Nagaraja under no choice and choice situations. Male and female moths were treated (T) with 150 or 200 Gy of gamma radiation, inbred or out-crossed to untreated (N) counterparts, and eggs laid by different crosses were offered to T. cryptophlebiae as host material. Newly laid (24 h old) eggs, as well as eggs that were 48 h and 72 h old were evaluated. In general, all egg treatments in the no choice experiments were acceptable for oviposition and suitable for parasitoid development. However, significant differences in the number of parasitised eggs were detected when one member of the host cross, particularly the female, was treated with gamma radiation or when the host egg age was greater than 24 h. No significant differences were detected in any of the choice experiments. Our results suggest that T. cryptophlebiae would accept, successfully develop in, and emerge from false codling moth eggs laid by the different crosses that would theoretically be present in the field under a sterile insect release programme for false codling moth and suggest that further evaluations combining releases of irradiated moths and parasitoids are warranted. (author)
[en] Within the framework of the study of Biocenotic insects related to conifer species in Traras, the Western region of Tlemcen, a comprehensive knowledge of the insect fauna hosted by the Aleppo pine (Pinus halepensisMill.), Thuya Barbary (Tetraclinis articulata(Vahl) Masters)) and Cypress green(Cupressus sempervirensL) is essential. The various methods used for capturing insects allowed the collection of a large number of species, but a large number still remains unknown. These species are distributed among 10 orders of which the most important are the Coleoptera, Hymenoptera and Lepidoptera. Through this list of insects and the nature of their food, six diets to which these species belong were identified. The most representative are herbivores, auxiliaries and borers. This inventory allows the compilation of a list of insects harmful to the conifer species studied in this region. They total species including 9 phytophagous, 8 xylophagous, 7 seed-eating species, 5 opophages and one gall species. The auxiliaries are present with 26 species. (author)
[en] Neotropical Piper species have bisexual flowers. Such reproductive trait is considered basal in this pantropical genus. However, neotropical species having unisexual (staminate) flowers along with bisexual ones have also been reported. Dichogamy is common in the genus, associated with either self-compatibility or incompatibility, as well as with entomophily. We analyzed a natural population of Piper caldense in an Atlantic Forest area (Vicosa municipality, Minas Gerais state, southeastern Brazil). Preliminary observations indicated that the species produces two flower types. We analyzed flower sex in spikes of 50 plants. We obtained additional information through morphological and anatomical studies and scanning electron microscopy analyses. The longevity and exposure dynamics of stigmatic papillae and the pollen release sequence of all four stamens were investigated to verify the degree of dichogamy. Pollination tests were performed, pollinators were identified and their visitation frequency was recorded. Piper caldense has both bisexual and staminate flowers, each flower type being located on separate spikes. These spikes occurred on the same plant, thus indicating andromonoecy; furthermore, plants having only spikes with staminate flowers were also observed. This gender had not yet been reported to the genus. Gradual and sequential exposure of stigmatic papillae associated with asynchronous pollen release (one stamen a day) resulted in incomplete protogyny. Hand pollination tests showed that the species is self-incompatible. Social bees, mainly Apis mellifera and Melipona spp., were the major pollinator group. Our study reinforces the need to associate morphological analysis with floral biology and indicates future changes in studies addressing reproductive traits associated with the phylogeny of the Piper genus.
[en] Anastrepha anomala Stone was obtained from Parahancornia amapa (Huber) Ducke (Apocynaceae) fruits, and Anastrepha hastata Stone from Cheiloclinium cognatum (Miers.) (Hippocrateaceae) in the State of Amapa, Brazil. Two braconids, Doryctobracon sp. and Opius bellus Gahan, were reared from the latter fruit fl y species. This is the fi rst record of P. amapa as a fruit fl y host. C. cognatum is the fi rst host known to A. hastata. Both braconids are also the fi rst records of parasitoids for this species. (author)