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7952. Hospodářství lesní
- Creator:
- Chadt-Ševětínský, Jan Evangelista
- Publisher:
- nákl. vl.
- Format:
- print and 18 s. ; v. 8°
- Type:
- model:monograph, text, and TEXT
- Subject:
- udc:630, Konspekt:24, agrovoc:UK01, Konspekt:Lesnictví, agroterm:lesní hospodářství, agroterm:lesy, agroterm:lesnictví, agroterm:dějiny, and czenas:Česko
- Language:
- Czech
- Description:
- (Statement of Responsibility) Jan Evang. Chadt
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7953. Hospodářství rybniční
- Creator:
- Theodor Mokrý
- Publisher:
- Nákladem vlastním
- Format:
- print and xiv, 352 s.
- Type:
- model:monograph and TEXT
- Language:
- Czech
- Description:
- T. Mokrý.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7954. Host condition effects upon Agrilus planipennis (Coleoptera: Buprestidae) captures on decoy-baited branch traps
- Creator:
- Domingue, Michael J., Berkebile, Jennifer, Steiner, Kim, Hall, Loyal P., Cloonan, Kevin R., Lance, David, and Baker, Thomas C.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, krascovití, polník, fenomenologie, beetles, Buprestidae, Agrilus, phenomenology, Coleoptera, Agrilus planipennis, emerald ash borer, exit hole, flight, invasive species, mate search, 2, and 59
- Language:
- English
- Description:
- We deployed branch traps in an ash (Fraxinus) plantation to investigate how Agrilus planipennis behavior is associated with Fraxinus pennsylvanica condition and dispersal patterns. Data were collected from traps with or without the presence of beetle visual decoys, and from a yearly survey of exit holes. The traps were placed on trees that were either clearly declining, with most foliage arising from epicormic sprouting, or on apparently healthy trees, with little evidence of damage or decline. We calculated correlations of exit holes among neighboring tree rings and also between exit holes and male trap captures. The damaged trees the traps were hung upon had more cumulative exit holes observed than the corresponding healthy trees. However, there was otherwise no evidence that the experiment was biased by differences in exit hole patterns of the surrounding trees. Male captures were greater on decoy-baited traps than controls and this decoy effect was most clearly apparent late in the season when traps were placed on healthy trees. There were also patterns of correlations between male captures and exit hole numbers that may be indicative of short-range mate finding-and dispersal behaviors. Female captures were sparser, but were positively affected by decoys on healthy and declining trees early in the season. Thus, the results suggest that the placement of such traps on healthier trees will maximize detection, and the branch traps also show promise for further use in dispersal studies., Michael J. Domingue, Jennifer Berkebile, Kim Steiner, Loyal P. Hall, Kevin R. Cloonan, David Lance, Thomas C. Baker., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7955. Host plants and aphid hosts influence the selection behaviour of three aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae)
- Creator:
- Albittar, Loulou, Ismail, Mohannad, Bragard, Claude, and Thierry Hance
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Aphidiinae, Aphididae, aphid, broad bean, host preference, parasitoid, plant influence, sugar beet, 2, and 59
- Language:
- English
- Description:
- Aphis fabae and Myzus persicae (Hemiptera: Aphididae) are insect pests that damage sugar beet and bean crops. Both are responsible for losses in yield and transmission of viral diseases, and may be present on the same host at the same time. Three parasitoid species, Aphidius colemani, Lysiphlebus testaceipes and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae) have the potential to be used as biological control agents against at least one of these species of aphids. As a first step prior to the implementation of a biological control program, our aim was to understand the host selection behaviour of the parasitoids, particularly when both aphids are present. We recorded the host acceptance (number of insertions of the ovipositor / number of antennal contacts), suitability (number of mummies / the number of insertions of the ovipositor) and emergence (number of adults emerging from mummies) of these three aphid parasitoids when parasitizing the two aphids. We also analyzed the effect of the host plant on the host preference of the parasitoid. Females of each parasitoid species (n = 15) were exposed to 20 aphids of A. fabae or M. persicae, or a mixture of these two species of aphids, for 15 min, on a leaf disc of each of the two host plants, sugar beet and bean. Higher host acceptance and suitability were recorded for A. colemani attacking both species of aphid: A. fabae (43 and 46%) and M. persicae (43 and 46%) on beet and bean plants respectively, compared to L. testaceipes and L. fabarum. L. testaceipes and L. fabarum showed a clear preference for A. fabae. L. fabarum accepted M. persicae on both plants only when it was mixed with A. fabae, probably due to a confusion effect. We found that the host plant played a significant role in host acceptance, host suitability. We conclude that A. colemani is the better of the three parasitoids studied for the biological control in bean, and particularly, sugar beet crops. and Loulou Albittar, Mohannad Ismail, Claude Bragard, Thierry Hance.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7956. Host spatial pattern influences induction of parasitization by Trichogramma (Hymenoptera: Trichogrammatidae)
- Creator:
- Voinovich, Nataliya D., Umarova, Taisiya Ya., and Sergey Ya.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, blanokřídlí, Trichogrammatidae, Trichogramma principium, samičky, parasitizmus, Sitotroga cerealella (hostitel), vajíčka hostitele, uspořádání vajíček, vztahy, 591.5, 576, and 595.2/.7
- Language:
- English
- Description:
- The influence of host intrapatch spatial distribution on parasitoid host acceptance behavior was investigated with Trichogramma principium parasitizing eggs of grain moth, Sitotroga cerealella. Single females were placed in Petri dishes, each containing 60 host eggs arranged either as a compact patch or partitioned into 60 or 12 clusters each consisting of 1 or 5 eggs, respectively. Partitioned patches provoked parasitization more often than compact patches. The percentage of ovipositing females (i.e., females parasitizing at least one of 60 host eggs) increased with the number of clusters, while it was independent of the intercluster distance over intervals of 2.5-15 mm. The mean number of eggs parasitized by ovipositing females during 48 h was almost independent of the host egg spatial pattern. As a result, the rate of parasitization was higher when the hosts were sparsely distributed within a patch than when they were aggregated., Nataliya D. Voinovich, Taisiya Ya. Umarova, Sergey Ya. Reznik, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7957. Host-finding behaviour of Cotylurus flabelliformis (Trematoda: Strigeidae) cercariae for snail hosts
- Creator:
- Campbell, Ronald A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Cotylurus, Strigeidae, Lymnaea stagnalis, cercariae, and chemoattraction
- Language:
- English
- Description:
- Cercariae of Cotylurus flabelliformis (Faust, 1917) were individually tested in 6 experiments for evidence of chemoattraction to snail hosts, host-speeificity, and rate of dispersal. Five species of snails were tested: Lymnaea stagnalis appressa Say, 1821, Stagnatola eludes (Say, 1821), Physella gyrina (Say, 1821), Planorbella trivnlvis (Say, 1817), and Oxyloma retusum (Lea, 1834). The data substantiate that cercariae of C. flabelliformis have a chemo-positive attraction to undetermined diffusable substances from snails, show host-specificity, and do not attack the snail that produced them. Cercarial response time was significantly influenced by cercarial age (post-emergence), and duration of presence of snails. Newly emerged cercariae were most consistently chemo-positive to L. stagnalis and quickly located all snail species except the unnatural host O. retusum. Tests of 121 cercariae proved statistically significant in showing preferences for snail hosts. Cercarial dispersal experiments showed that C. flabelliformis cercariae can disperse rapidly but few located and penetrated lab-reared S. eludes at distances up to 1.2 m. The results are consistent with other studies which indicate that chemical gradients are used by cercariae to locate slow moving hosts and that cercariae must come into close proximity of snails before attraction occurs. The significance of these observations to the distribution of C. flabelliformis in the molluscan population is discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7958. Host-parasite interface between Asellus Aquaticus (Iopoda) and larvae of Acantocephalus Anguillae (Acanthocephala)
- Creator:
- Dezfuli, Bahram Sayyaf
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7959. Host-parasite relationships of Zootoca vivipara (Sauria: Lacertidae) in the Pyrenees (North Spain)
- Creator:
- Sanchis, Vanessa, Roig, Juan M., Carretero, Miguel A., Roca, Vicente, and Llorente, Gustavo A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- helminths, Oswaldocruziafìliformis, host-parasite relationships, Zootoca vivìpara, Pyrenees, and Spain
- Language:
- English
- Description:
- The helminths infesting the common lizard, Zootoca vivipara (Jacquin, 1787), were studied with special attention to the relations between the number of nematodes, Oswaldocruzia filiformis (Goezc,1782), and the size, sex and age class of the host. The possible seasonality of the parasite intensity and the relationship with the feeding habits of the host were also tested. Helminth infracommunities of Z. vivipara were depauperate with lizards harbouring only two species, the tremalode Plagiorchis molini (Lent et Freitas, 1940) and the nematode O, filiformis. A positive correlation between host size and the number of O. filiformis was found for female Z. vivipara. However, no correlation was detected between intensity and sex or age class. The feeding habits of Z. vivipara, the isolation of the population studied and the low level of interaction with other reptilian or amphibian species are suggested as the causes of the depauperate helminth infracommunities found in this laccrtid lizard.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7960. Host-plant mediated influences on population development of Sitobion avenae (Sternorrhyncha: Aphididae)
- Creator:
- Alois Honěk and Martinková, Zdenka
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Aphididae, Sitobion avenae, vývoj populace, hostitelské rostliny, obilniny, ozimá pšenice, vliv kultivaru, vliv hustoty porostu, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- We investigated the effects of genetic differences and host plant density on population development of the rose-grain aphid Sitobion avenae (F.) (Sternorrhyncha: Aphididae) in winter wheat stands. Aphid numbers on ears were recorded on 11 cultivars (6 years) and on plots where crop density was varied by thinning (12 years). Crop density significantly affected whole plant, tiller and ear mass, number of tillers, and leaf area and chlorophyll content. The duration and rate of aphid population growth, and the maximum numbers of aphids were ascertained by weekly counts. Maximum abundances increased with the length of time available for the growth of aphid populations while the rate of population growth was less important. Variation of maximum numbers of S. avenae on different cultivars was not significant, probably due to the small variation in the period available for the development of aphid populations. By contrast, there was a significant Variation of aphid performance associated with host plant density. Aphid populations on solitary plants persisted longer and became more abundant than in dense stands. The prolonged survival of aphid populations was probably caused by an extended period of tillering and lower average age of tillers of solitary plants. There was large annual variation in aphid abundance. It is likely that modifications of host plant development caused by differences in winter weather may contribute to this variation., Alois Honěk, Zdenka Martinková, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public