Intra- and inter-clonal variation in gypsy moth larval performance on bigtooth and trembling aspen

1992 ◽  
Vol 22 (11) ◽  
pp. 1676-1683 ◽  
Author(s):  
Charley A. Chilcote ◽  
John A. Witter ◽  
Michael E. Montgomery ◽  
Jennifer L. Stoyenoff
Keyword(s):  
Gypsy Moth ◽  
Growth Rates ◽  
Larval Growth ◽  
Clonal Variation ◽  
Larval Performance ◽  
Trembling Aspen ◽  
Lower Growth ◽  
Relative Growth Rates ◽  
Fine Mesh ◽  
Window Of Vulnerability

A field study on the effects of interclonal and intraclonal variations of aspens on the performance of gypsy moth, Lymantriadispar (L.), was conducted in Michigan during 1988 and 1989. Study species were trembling aspen, Populustremuloides Michx., and bigtooth aspen, Populusgrandidentata Michx. Larvae were caged on intact host trees in the field in fine mesh bags. We examined the leaf phenological development of aspen clones and its relationship to a number of insect parameters: larval weight, relative growth rates, survival, and pupal weights. Interclonal variations in larval growth on trembling aspen clones and bigtooth aspen clones were high in 1988 and 1989. Leaf phenological differences between clones also were highly significant. These differences in leaf phenology led to a window of vulnerability existing for each clone. While insects that initiated feeding on phenologically delayed clones had poorer survival and lower growth rates than did larvae on more phenologically advanced clones, later in the season these larvae were able to catch up as the phenology of delayed clones caught up to that of more advanced clones. Because of this, pupal weights did not show significant effects of clones. Intraclonal variation in larval growth was extremely low for all growth periods. While there were significant differences in phenology between ramets within clones, the variation was much less than the variation seen in phenological differences between clones. Phenology of caged branches within a tree did not vary significantly for either species.

Growth Rates and Growth Efficiencies in Larvae and Juveniles of Rutilus rutilus and Other Cyprinid Species: Effects of Temperature and Food in the Laboratory and in the Field

1988 ◽  
Vol 45 (6) ◽  
pp. 943-950 ◽  
Author(s):  
W. Wieser ◽  
H. Forstner ◽  
F. Schiemer ◽  
W. Mark
Keyword(s):  
Growth Rates ◽  
Cold Water ◽  
Juvenile Fish ◽  
Larval Growth ◽  
Rutilus Rutilus ◽  
Growth Efficiency ◽  
Gut Contents ◽  
Sudden Increase ◽  
Roach Rutilus Rutilus ◽  
Relative Growth Rates

Growth rates were determined in four 0+ class populations of roach (Rutilus rutilus): two from warm backwaters of the Danube and two from cold-water lakes. Larval growth was also determined in the laboratory for R. rutilus, Leuciscus cephalus, and Alburnus alburnus at 15, 20, and 25 °C. Q10 values of growth rates were low (1.29–1.67) between 20 and 25 °C but were high (3.9) between 15 and 20 °C. Net growth efficiency of the larvae of R. rutilus ranged from 68.6 to 71.9% at 15 °C and from 72.3 to 73.5% at 20 °C. A comparison of temperature-corrected relative growth rates in the four populations of roach revealed significant differences between the two warmwater and the two cold-water populations. Growth of warmwater populations was fastest right after hatching and then declined in a fairly regular way. Growth of cold-water populations was slow after hatching but increased later. These differences reflect interactions between temperature and food availability in the two types of water bodies. The sudden increase in growth rate in the population from the coldest lake can be correlated with a change in gut contents which in turn reflects the improved ability of the juvenile fish for catching Zooplankton.

scholarly journals Leaf Induction Impacts Behavior and Performance of a Pollinating Herbivore

2021 ◽  
Vol 12 ◽  
Author(s):  
Deidra J. Jacobsen ◽  
Robert A. Raguso
Keyword(s):  
Volatile Compounds ◽  
Growth Rates ◽  
Floral Scent ◽  
Larval Growth ◽  
Oviposition Preference ◽  
Host Plant Selection ◽  
Larval Performance ◽  
Oviposition Choice ◽  
And Control ◽  
Artificial Flowers

Flowering plants use volatiles to attract pollinators while deterring herbivores. Vegetative and floral traits may interact to affect insect behavior. Pollinator behavior is most likely influenced by leaf traits when larval stages interact with plants in different ways than adult stages, such as when larvae are leaf herbivores but adult moths visit flowers as pollinators. Here, we determine how leaf induction and corresponding volatile differences in induced plants influence behavior in adult moths and whether these preferences align with larval performance. We manipulated vegetative induction in four Nicotiana species. Using paired induced and control plants of the same species with standardized artificial flowers, we measured foraging and oviposition choices by their ecologically and economically important herbivore/pollinator, Manduca sexta. In parallel, we measured growth rates of M. sexta larvae fed leaves from control or induced plants to determine if this was consistent with female oviposition preference. Lastly, we used plant headspace collections and gas chromatography to quantify volatile compounds from both induced and control leaves to link changes in plant chemistry with moth behavior. In the absence of floral chemical cues, vegetative defensive status influenced adult moth foraging preference from artificial flowers in one species (N. excelsior), where females nectared from induced plants more often than control plants. Plant vegetative resistance consistently influenced oviposition choice such that moths deposited more eggs on control plants than on induced plants of all four species. This oviposition preference for control plants aligned with higher larval growth rates on control leaves compared with induced leaves. Control and induced plants of each species had similar leaf volatile profiles, but induced plants had higher emission levels. Leaves of N. excelsior produced the most volatile compounds, including some inducible compounds typically associated with floral scent. We demonstrate that vegetative plant defensive volatiles play a role in host plant selection and that insects assess information from leaves differently when choosing between nectaring and oviposition locations. These results underscore the complex interactions between plants, their pollinators, and herbivores.

The missing links: larval and post-larval development of the ascoglossan opisthobranch Elysia viridis

2000 ◽  
Vol 80 (6) ◽  
pp. 1087-1094 ◽  
Author(s):  
Cynthia D. Trowbridge
Keyword(s):  
Larval Development ◽  
Growth Rates ◽  
Shell Length ◽  
Larval Growth ◽  
Model Organism ◽  
Larval Life ◽  
Codium Fragile ◽  
Planktotrophic Larvae ◽  
Algal Diet ◽  
Better Than

The stenophagous ascoglossan (=sacoglossan) opisthobranch Elysia viridis has long been a model organism for the study of endosymbiosis or kleptoplasty as well as one of the few herbivores to consume the introduced green macroalga Codium fragile on European shores. Larval and post-larval dynamics of the ascoglossan were investigated. Planktotrophic larvae of E. viridis grew at 5–10 μm d−1 (shell length) at 15°C on a unicellular algal diet (the cryptophyte Rhodomonas baltica); larvae became competent one month post-hatching. Effective feeding and chloroplast acquisition typically started within 2–3 d of metamorphosis. Slugs grew about 8 mm in the first month of post-larval life. During this period, juveniles held in the light did not grow faster or survive better than conspecifics held in the dark; thus, functional kleptoplasty did not occur during first three weeks of benthic life. While larval growth rates and the nature of metamorphic cues are consistent with those of many other opisthobranch species with planktotrophic larvae, measures of post-larval growth—particularly as it pertains to kleptoplasty—is a new contribution to opisthobranch biology.

Selection for biomass production based on respiration parameters in eucalypts: effects of origin and growth climates on growth rates

1996 ◽  
Vol 26 (9) ◽  
pp. 1556-1568 ◽  
Author(s):  
Thimmappa S. Anekonda ◽  
Richard S. Criddle ◽  
Lee D. Hansen ◽  
Mike Bacca
Keyword(s):  
Temperature Dependence ◽  
Growth Rates ◽  
Heat Rate ◽  
Eucalyptus Species ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Metabolic Heat ◽  
Respiratory Parameters ◽  
Metabolic Heat Rate ◽  
Different Climates

Seventeen Eucalyptus species and 30 rapid-growing Eucalyptuscamaldulensis trees (referred to as plus trees), growing in a plantation were studied to examine relationships among measured plant growth and respiratory parameters, geographical origins, and growth climate. The respiratory parameters measured at two different temperatures by isothermal calorimetry were metabolic heat rate, rate of CO2 production, and the ratio of heat rate to CO2 rate. Metabolic heat rate was also measured as a continuous function of temperature by differential scanning calorimetry in the range of 10 to 40 °C. Tree growth was measured as rates of height and stem volume growth. The values of respiratory and growth variables of Eucalyptus species are significantly correlated with latitude and altitude of origin of their seed sources. The maximum metabolic heat rate, the temperature of the maximum heat rate, the temperature coefficients of metabolic rate, and the temperatures at which the slopes of Arrhenius plots change are all genetically determined parameters that vary both within and among species. Measurement of growth rate–respiration rate–temperature relationships guide understanding of why relative growth rates of Eucalyptus species and individual genotypes differ with climate, making it possible to identify genotypes best suited for rapid growth in different climates. The temperature dependence of respiration rates is an important factor determining relative growth rates of eucalypts in different climates. To achieve optimum biomass production the temperature dependence of individual plants must be matched to growth climate.

Studies on the sowing dates of cotton in the Sudan Gezira: I. The influence of date of sowing on plant growth and development

1967 ◽  
Vol 69 (3) ◽  
pp. 305-315 ◽  
Author(s):  
J. E. Jackson
Keyword(s):  
Growth Rates ◽  
Slow Growth ◽  
Seasonal Pattern ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Research Division ◽  
Sowing Dates ◽  
Net Assimilation ◽  
State Growth ◽  
Sudan Gezira

Growth analysis of cotton crops sown in the Sudan Gezira at monthly intervals between August and May revealed a marked seasonal pattern of growth. Irrespective of plant age and fruiting state growth of non-senescent plants was slowest during the cool winter months. Relative growth rates of young plants were highest in August, September and early October due to the high specific leaf areas and fairly high net assimilation rates found then. They were lowest when minimum temperatures were lowest. Net assimilation rates were also lowest in the coolest months, probably as a result of restricted growth. High temperatures in the spring reduced fruiting. It is concluded that low minimum temperatures and high evaporation rates are both associated with slow growth, and play a large part in determining the characteristic decline of growth rates of cotton sown at the usual date in August.I wish to thank the Chief of the Research Division, Ministry of Agriculture, Sudan, for permission to publish this paper and to record my gratitude to the team of field and laboratory assistants, especially Salih Saad and Hassan Osman, who helped in the work.

Wounding of aspen roots promotes suckering

2004 ◽  
Vol 82 (3) ◽  
pp. 310-315 ◽  
Author(s):  
Erin C Fraser ◽  
Victor J Lieffers ◽  
Simon M Landhäusser
Keyword(s):  
Populus Tremuloides ◽  
Growth Rates ◽  
Growing Season ◽  
Organic Layer ◽  
Trembling Aspen ◽  
Layer Depth ◽  
Injury Type ◽  
Organic Layers ◽  
Root Injury ◽  
Root Sucker

In early May, 1-m sections of trembling aspen (Populus tremuloides Michx.) roots in a forest cutblock were carefully exposed and examined for damage. Undamaged roots were subjected to one of three wounding treatments (scrape, sever, or uninjured control) and were then reburied to either the full normal organic layer depth or to one third of the normal depth. Following one growing season, the roots were reexposed and assessed for aspen sucker numbers and growth rates. Results indicate that injured roots produced suckers nearly twice as often as uninjured roots. Further, injured roots produced more suckers per root, and these suckers were taller and had greater leaf area. Roots buried under shallow organic layers also generated more suckers, regardless of injury type. The side of injury (distal or proximal) did not affect any of the measured variables. The present study suggests that moderate wounding of aspen roots increases initial sucker numbers and growth rates.Key words: trembling aspen, root sucker, root injury, regeneration.

Effects of lice infestation on the growth of beef heifers in Victoria

1984 ◽  
Vol 24 (125) ◽  
pp. 140 ◽  
Author(s):  
PJ Bailey ◽  
WAD Carroll ◽  
B Knee
Keyword(s):  
Growth Rates ◽  
Beef Heifers ◽  
Lower Growth ◽  
High Rainfall ◽  
Main Species ◽  
Western Victoria ◽  
Linognathus Vituli

Ten experiments were carried out to examine some of the effects of lice infestation on heifers grazing on six commercial properties in the high rainfall areas of Victoria. In all experiments, famphur, a pour-on lousicide, effectively controlled lice populations (main species Linognathus vituli). Lice infestation was associated with lower growth rates in only two experiments. Significant correlations between lice infestation and liveweight gain of untreated heifers were found in three of ten experiments, but infestation accounted for only 23-30% of the variation in liveweight gain. The results support other studies conducted in Western Victoria, and the need for routine whole herd treatment against lice is questioned.

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