Larval food source promotes cyclic seasonal variation in polyandry in the moth Lobesia botrana

The objective of this study was to analyze the diet of fish species that use the mangrove vegetation for shelter and feeding in a river southeastern Brazil. The fieldwork, including collecting and underwater observations, was carried out in the dry (July and August 2004) and in the rainy season (February and March 2005) in order to assess the existence of seasonal variation in the diets. Seven kinds of food items were consumed, two of plant origin and five of animal origin. Crustaceans predominated in the diet of most species, either in the form of unidentified fragments or discriminated in eight groups. The predominance of species using mainly a single food source (crustaceans, principally Ostracoda and Tanaidacea) and the existence of seasonal variation in the diets of some species became very evident in the analysis food niche breadth, with a predominance of dietary specialists. In the Rio da Fazenda mangrove, the submersed marginal vegetation was used by the ichthyofauna as a locale for foraging, and principally as cover by bottom-feeding species. These species may be using the vegetation for protection from aerial and aquatic predators, or even from the pull of the current during the turn of the tide. In the study area, the great diversity of crustaceans constitutes an important food source for most fish species which adjusted their diet according to seasonal changes in food availability and to interactions with other species.

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Vine phenological stage during larval feeding affects male and female reproductive output of Lobesia botrana (Lepidoptera: Tortricidae)

Bulletin of Entomological Research ◽

10.1017/s000748539900070x ◽

1999 ◽

Vol 89 (6) ◽

pp. 549-556 ◽

Cited By ~ 28

Author(s):

L.M. Torres-Vila ◽

M.C. Rodríguez-Molina ◽

R. Roehrich ◽

J. Stockel

Keyword(s):

Body Weight ◽

Reproductive Output ◽

Lobesia Botrana ◽

Crop Damage ◽

Reproductive Efficiency ◽

Larval Feeding ◽

Phenological Stage ◽

Semisynthetic Diet ◽

Larval Food ◽

Potential Factor

AbstractThe effect of vine phenological stage during larval feeding on the reproductive output of Lobesia botrana (Denis & Schiffermüller) adults was assessed. Larvae were reared under field conditions on vine inflorescences, unripe or ripe berries simulating the first, second and third insect generations respectively. The resulting adults showed significant differences in body weight, longevity and reproductive output as measured by oviposition period, total fecundity and reproductive efficiency (viable eggs/body weight) for females, and spermatophore number and volume of the first spermatophore for males. Viable egg number was positively correlated with female body weight for all treatments but male reproductive efficiency (spermatophores/body weight) was not. The reproductive output of females from larvae reared on a standard semisynthetic diet was comparable to that of females reared on ripe berries whereas males showed a higher reproductive output when reared on semisynthetic diet. These results clearly show that data obtained from insects reared on artificial diet cannot be extrapolated to ‘field-derived’ adults. The results suggest that the variation in L. botrana reproductive output due to the larval food source should be taken into account as a potential factor affecting insect population dynamics. It is suggested that different intervention thresholds, such as those based on pheromone catches, may be needed for each of the three moth generations, to compensate for the increased fecundity and potential to cause larger amounts of crop damage of later generations.

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Larval Conditioning and Aging of Sand Fly Rearing Medium Affect Oviposition Site Selection in Phlebotomus papatasi (Diptera: Psychodidae) Sand Flies

Journal of Medical Entomology ◽

10.1093/jme/tjab063 ◽

2021 ◽

Author(s):

Lindsey R Faw ◽

Kasie Raymann ◽

Nayma Romo Bechara ◽

Gideon Wasserberg

Keyword(s):

Conditioned Medium ◽

Food Source ◽

Food Sources ◽

Sand Fly ◽

Larval Rearing ◽

Sand Flies ◽

Phlebotomus Papatasi ◽

Larval Food ◽

Gravid Females ◽

Larval Conditioning

Abstract Sand fly larvae develop in sheltered humid habitats containing decaying organic matter on which they feed. Previously, we showed that gravid females of Phlebotomus papatasi Scopoli (Diptera: Psychodidae) are attracted to and stimulated to lay eggs on larval rearing medium containing larvae. That study, however, did not control for the possible effect of medium aging. Our goal in this study was to evaluate the effect of larval substrate conditioning on attraction and oviposition responses of Ph. papatasi sand flies while controlling for the effect of substrate aging. Initially, we confirmed that the pretreatment fresh larval food sources (to be used as larval conditioned and unconditioned media) did not differ with respect to their effect on attraction and oviposition responses. The larval conditioned medium was produced by rearing larvae to the second/third-instar stage over 3 wk using the same larval food source. To produce larval unconditioned medium, the same amount of fresh larval food was added to a control rearing cup that did not contain larvae but was aged under identical time and conditions. Two-choice bioassays were conducted to evaluate gravid female’s attraction and oviposition response to larval conditioned and unconditioned media. We found that gravid females were significantly attracted (P < 0.05) to larval conditioned medium when compared with unconditioned medium under the same amount of time and conditions. However, no such difference was found with respect to oviposition response. Both attraction and oviposition responses were significantly increased for larval conditioned and unconditioned media in comparison to the initial fresh larval food source.

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Importance of the macrofauna for the feeding of young fish species from infralittoral of Arrozal: Cananeia lagoon estuarine region (25º02'S-47º56'W) - Brazil

Boletim do Instituto Oceanográfico ◽

10.1590/s0373-55241993000100004 ◽

1993 ◽

Vol 41 (1-2) ◽

pp. 39-52 ◽

Cited By ~ 6

Author(s):

Yoko Wakabara ◽

Airton S. Tararam ◽

Maurea N. Flynn

Keyword(s):

Seasonal Variation ◽

Fish Species ◽

Food Source ◽

Sampling Site ◽

The Other ◽

Nursery Ground ◽

Young Fish ◽

The Third ◽

Balanced Diet ◽

Estuarine Region

The aim of this study was to establish the importance of the macrofauna as food for young fish species that inhabit the infralittoral adjacent to the lower marsh. The sampling site is located at Arrozal, Cananéia lagoon estuarine region (25º02'S and 47º56'W) and the collectings were realized monthly, during a year. The results suggest that the studied area could be considered as a nursery ground for young fish species. The local macrofauna is composed mainly by several groups of crustaceans and has a marked temporal variation. Mysids were dominant in Spring, copepods in Summer, mysids and bivalves were co-dominants in the Autumn and amphipods in Winter. Mysids, copepods, ostracods, tan aids and other epifaunal crustaceans were more consumed than other items. According to the trophic habits, the twelve fish species could be divided into three groups: the first and the third as mysids and copepods eaters respectively, and the second group with a balanced diet reflecting more than the other groups the seasonal variation of the macrofauna collected by the dredge. Benthonic and benthopelagic organisms were considered the major food source, being consumed by 75% of the analysed fish species, in Cananéia infralittoral.

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Oviposition patterns and the supplementary role of a seed-feeding weevil, Rhyssomatus marginatus (Coleoptera: Curculionidae), in the biological control of a perennial leguminous weed, Sesbania punicea

Bulletin of Entomological Research ◽

10.1017/s0007485300041122 ◽

1992 ◽

Vol 82 (3) ◽

pp. 343-347 ◽

Cited By ~ 10

Author(s):

J.H. Hoffmann ◽

V.C. Moran

Keyword(s):

Biological Control ◽

Food Source ◽

Biological Control Agent ◽

Reproductive Potential ◽

Control Agent ◽

Larval Food ◽

Intraspecific Interactions ◽

Host Plant Location ◽

Selection Of

AbstractA seed-feeding curculionid, Rhyssomatus marginatus Fåhraeus, was introduced into South Africa for biological control of a perennial leguminous weed, Sesbania punicea, from South America. R. marginatus has become established even though its larval food source, seeds in ripening pods, is severely depleted by another biological control agent, an apionid, Trichapion lativentre (Beguin Billecocq), which destroys nearly all the flower-buds produced by the plants and reduces seed-set by 98% on average. In spite of this indirect competition, R. marginatus destroys up to 88% of the remaining seeds that develop on S. punicea, regardless of host plant location. Detrimental intraspecific interactions between larvae of R. marginatus are minimized, and the utilization of a depleted food source is optimized, through meticulous selection of oviposition sites by the female weevils. Although numerically inferior, R. marginatus is an important supplementary agent to T. lativentre and together the two species of weevils have almost arrested the reproductive potential of S. punicea.

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Microzooplankton as a food source for the Pacific oyster Crassostrea gigas: seasonal variation in gut contents and food availability

Fisheries Science ◽

10.1007/s12562-011-0409-9 ◽

2011 ◽

Vol 77 (6) ◽

pp. 961-974 ◽

Cited By ~ 10

Author(s):

Takashi Kamiyama

Keyword(s):

Seasonal Variation ◽

Food Availability ◽

Crassostrea Gigas ◽

Food Source ◽

Pacific Oyster ◽

Gut Contents ◽

The Pacific

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SEM Observations on the Germination of Euonymous Americanus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119363 ◽

1985 ◽

Vol 43 ◽

pp. 508-509

Author(s):

D.R. Hill ◽

J.R. McCurry ◽

L.P. Elliott ◽

G. Howard

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Light Microscopy ◽

Filter Paper ◽

Room Temperature ◽

Food Source ◽

Environmental Chamber ◽

Dormant Stage ◽

Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

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