Variable responses of folivorous sawflies to leaf quality of mountain birch

2005 ◽  
Vol 35 (1) ◽  
pp. 189-198 ◽  
Author(s):  
Marianna Riipi ◽  
Antti Kause ◽  
Erkki Haukioja ◽  
Vladimir Ossipov ◽  
Svetlana Ossipova ◽  
...  
Keyword(s):  
Larval Growth ◽  
Leaf Traits ◽  
Mountain Birch ◽  
Leaf Water Content ◽  
Larval Performance ◽  
Leaf Quality ◽  
Tree Resistance ◽  
Leaf Consumption ◽  
Birch Trees ◽  
Herbivore Consumption

We studied whether the larval performance of four sawfly species feeding on mountain birch (Betula pubescens subsp. czerepanovii (Orlova) Hämet-Ahti) leaves at different times of the growing season was related to the same chemical and physical leaf traits. In the three phenologically earliest species, larval growth was related to the same set of leaf traits. In contrast, consumption of leaf material was related to different leaf traits in all of the four species. Leaf suitability for herbivore growth and tree resistance to herbivore consumption were thus not always determined by the same leaf traits. Leaf water content and toughness had the strongest associations with larval performance. Phenolics, which are often considered the main resistance compounds in deciduous trees, explained only a small part of the variance in leaf consumption, but some groups of phenolics were negatively related to larval growth. In conclusion, the same mountain birch trees were not resistant to all of the studied sawflies in terms of leaf consumption, but low leaf suitability, which was related to the same set of leaf traits in the case of three sawfly species, may serve birch resistance, e.g., by exposing larvae to natural enemies for a longer period.

Leaf traits influencing oviposition preference and larval performance ofCameraria ohridellaon native and novel host plants

2014 ◽  
Vol 152 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Lilla D'Costa ◽  
Monique S.J. Simmonds ◽  
Nigel Straw ◽  
Bastien Castagneyrol ◽  
Julia Koricheva
Keyword(s):  
Host Plants ◽  
Oviposition Preference ◽  
Leaf Traits ◽  
Larval Performance ◽  
Novel Host

scholarly journals Relationships between Foliar Fungal Endophyte Communities and Ecophysiological Traits of CAM and C3 Epiphytic Bromeliads in a Neotropical Rainforest

Diversity ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 378 ◽  
Author(s):  
Peter H. Tellez ◽  
Carrie L. Woods ◽  
Stephen Formel ◽  
Sunshine A. Van Bael
Keyword(s):  
Fungal Endophytes ◽  
Leaf Traits ◽  
Fungal Endophyte ◽  
Leaf Water Content ◽  
Leaf Toughness ◽  
Vascular Epiphytes ◽  
Ecophysiological Traits ◽  
Photosynthetic Pathways ◽  
Relative Abundances ◽  
Epiphytic Bromeliads

Vascular epiphytes contribute up to 35% of the plant diversity and foliar biomass of flowering plants. The family Bromeliaceae is a monophyletic group of plants native to the Neotropics. Epiphytic bromeliads form associations with distinct groups of organisms but their relationship with foliar fungal endophytes remain underexplored. In this study we examined the relationship of foliar fungal endophytes to host photosynthetic pathways and associated ecophysiological traits. We sampled the fungal endophyte communities of 67 host individuals in six epiphytic bromeliad species differing in C3 and crassulacean acid metabolism (CAM) photosynthetic pathways. We tested whether endophyte assemblages were associated with ecophysiological leaf traits related to host photosynthetic pathways. Our results indicate that (1) C3 and CAM bromeliads host dissimilar endophyte assemblages, (2) endophyte communities in C3 bromeliads are characterized by variable relative abundances of fungal orders; conversely, CAM associated endophyte communities were characterized by consistent relative abundances of fungal orders, and (3) endophyte communities in bromeliads are distributed along a continuum of leaf toughness and leaf water content. Taken together, our study suggests that host physiology and associated ecophysiological traits of epiphytic bromeliads may represent biotic filters for communities of fungal endophytes in the tropics.

scholarly journals Diet-induced differences in the essential fatty acid (EFA) compositions of larval Atlantic cod (Gadus morhua L.) with reference to possible effects of dietary EFAs on larval performance

2006 ◽  
Vol 63 (2) ◽  
pp. 302-310 ◽  
Author(s):  
C.J. Cutts ◽  
J. Sawanboonchun ◽  
C. Mazorra de Quero ◽  
J.G. Bell
Keyword(s):  
Fatty Acid ◽  
Essential Fatty Acid ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Lipid Level ◽  
Larval Growth ◽  
Somatic Tissue ◽  
Larval Performance ◽  
Experimental Diet ◽  
Live Feed

Abstract We studied the performance of cod rearing in which live feed was given under three different essential fatty acid (EFA) enrichment regimes, using commercially available live-feed enrichments. We assessed the fatty acid profile [docosahexaenoic (DHA), eicosapentaenoic (EPA), and arachidonic acid (AA)] in larval somatic tissue, relative to its amounts in both rotifers and Artemia as well as to larval performance. Overall, percentage lipid level of each experimental diet for the trial was approximately 50%. Further, there were no significant differences in total fatty acid levels of larvae from each treatment at the end of the trial (mean = 444.76 μg fatty acid per mg lipid). However, during the rotifer phase, larvae from each treatment were able to incorporate comparable levels of %DHA, irrespective of levels in the diet. Despite this, the rotifer diet with more %DHA still promoted better larval growth than other treatments. Conversely, larvae from two of the treatments did not exhibit any accumulation of AA, reflecting levels found in the diet instead. However, between-tank differences in larval %AA showed improved growth during the rotifer period when larval %AA was high. Low ratios of EPA had no effect. During the Artemia phase, percentage levels of larval DHA decreased; there was no accumulation of DHA relative to dietary levels, which in Artemia were significantly lower than in rotifers (6 cf. 20–30%). However, DHA levels in larvae at the end of the experiment correlated positively with survival. Artemia contained lower levels of AA than rotifers (1.5 cf. 3.0%), yet comparable levels of AA were found in rotifer-fed and Artemia-fed larvae. This also differed significantly between treatments, and correlated positively with survival.

scholarly journals Effects of rotifer densities on larval performance of spotted scat (Scatophagus argus)

2021 ◽  
Vol 13 (Aquaculture) ◽  
pp. 37-43
Author(s):  
Quoc Viet Le ◽  
Van Khanh Ly ◽  
Thi My Han Duong ◽  
Nguyen Duy Khoa Tran ◽  
Tomonari Kotani ◽  
...  
Keyword(s):  
Survival Rate ◽  
Growth Performance ◽  
Body Length ◽  
Fish Larvae ◽  
Larval Growth ◽  
Larval Performance ◽  
Scatophagus Argus ◽  
Wide Range ◽  
Significant Difference ◽  
Set Up

This study is aimed to determine the optimal rotifer feeding density for larviculture of spotted scat fish (Scatophagus argus). The experiment was randomly set up in triplicate with 5 treatments including 5, 10, 15, 20 and 25 rotifers/mL. The fish larvae with the initial body length and depth at 2,343 ± 110 µm and 812 ± 85µm, respectively, were stocked in 250-L tanks at 10 larva/L of density and 25‰ of salinity. After 21 days of rearing, the results showed that the larval growth were at 243 – 330 µm/day of DLG and 5.50 – 6.70 %/day of SGRL; 131 –204 µm/day of DDG and 7.20 – 8.93 %/day of SGRD, but no significant difference in larval growth performance was recorded among treatments (p>0.05). However, the highest survival rate of fish larvae (35.4-48.1%) was recorded in the treatments fed 5 and 10 rotifers/mL and was significantly higher than other treatments (p<0.05). The data demonstrated that spotted scat larvae fed effectively across as wide range of rotifer densities and the range at 5-10 rotifers/mL were suggested for the husbandry practices.

scholarly journals Silicon Fertilisation Affects Morphological and Immune Defences of an Insect Pest and Enhances Plant Compensatory Growth

2021 ◽  
Author(s):  
Tarikul Islam ◽  
Ben D. Moore ◽  
Scott N. Johnson
Keyword(s):  
Compensatory Growth ◽  
Brachypodium Distachyon ◽  
Insect Pest ◽  
Larval Growth ◽  
Leaf Consumption ◽  
Physical Defence ◽  
Model Grass ◽  
Defensive Behaviours ◽  
Immune Defences ◽  
Leaf Trichome

Abstract Insect herbivores employ various defences, including morphological, behavioural, and immune responses against their natural enemies (e.g., predators, parasitoids) which can make biocontrol of herbivorous pests challenging. Silicon (Si) accumulation in plants is a potent physical defence against herbivores. However, it remains uncertain how Si affects pest defences to their enemies and plant defences following herbivore attack. We grew the model grass, Brachypodium distachyon, hydroponically with (+Si) or without (–Si) Si and investigated the impacts of Si on morphological (integument resistance and thickness), behavioural (flee, headrear, thrash, and regurgitation), and immune defences of the cotton bollworm, Helicoverpa armigera. We further examined the effects of Si on plant compensatory growth and leaf trichome production. Larval growth, leaf consumption, and integument resistance were lower when feeding on +Si plants compared to when feeding on –Si plants. Larval integument thickness, defensive behaviours, hemocyte density and lysozyme-like activity in the hemolymph were unaffected by Si. Larvae fed on +Si plants had higher hemolymph phenoloxidase (PO) and total-PO activities than larvae fed on –Si plants, although this did not enhance larval melanisation response. Furthermore, Si supply increased plant compensatory growth and constitutive trichome production whereas herbivory induced trichome production only on –Si plants. We provide the first evidence that Si fertilisation affects insect defences in addition to reducing their growth and feeding. Lower integument resistance might enhance larval vulnerability to parasitoids and pathogens and higher PO activities could impose fitness costs (e.g., delayed development), potentially increasing overall insect susceptibility to enemies.

scholarly journals Ant-Related Oviposition and Larval Performance in a Myrmecophilous Lycaenid

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Matthew D. Trager ◽  
Matthew D. Thom ◽  
Jaret C. Daniels
Keyword(s):  
Egg Production ◽  
Host Plants ◽  
Life History Traits ◽  
Interspecific Interactions ◽  
Larval Growth ◽  
Oviposition Preference ◽  
Larval Performance ◽  
Costs And Benefits ◽  
Miami Blue Butterfly ◽  
Measures Of Performance

We experimentally assessed ant-related oviposition and larval performance in the Miami blue butterfly (Cyclargus thomasi bethunebakeri). Ant tending had sex-dependent effects on most measures of larval growth: female larvae generally benefitted from increased tending frequency whereas male larvae were usually unaffected. The larger size of female larvae tended by ants resulted in a substantial predicted increase in lifetime egg production. Oviposition by adult females that were tended byC. floridanusants as larvae was similar between host plants with or without ants. However, they laid relatively more eggs on plants with ants than did females raised without ants, which laid less than a third of their eggs on plants with ants present. In summary, we found conditional benefits for larvae tended by ants that were not accompanied by oviposition preference for plants with ants present, which is a reasonable result for a system in which ant presence at the time of oviposition is not a reliable indicator of future ant presence. More broadly, our results emphasize the importance of considering the consequences of variation in interspecific interactions, life history traits, and multiple measures of performance when evaluating the costs and benefits of mutualistic relationships.

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