Fluoride Loading of Larvae of Pine Sawfly from a Polluted Site

1992 ◽  
Vol 29 (1) ◽  
pp. 63 ◽  
Author(s):  
M. T. Davies ◽  
A. W. Davison ◽  
G. R. Port
Keyword(s):  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Ufere N. Uka ◽  
Ebenezer J. D. Belford ◽  
Florence A. Elebe

AbstractThis study was undertaken to examine changes in the content of pigments and accumulation of metals from vehicular pollution in selected species of roadside trees under vehicular pollution. A major arterial road with heavy vehicle emissions in the Kumasi Metropolis was designated as the polluted site, while Kwame Nkrumah University of Science and Technology Campus was designated as the control site. Four tree species (Terminalia catappa, Mangifera indica, Ficus platyphylla and Polyalthia longifolia) selected for the study were well distributed and abundant in the polluted and control sites. Photosynthetic pigments and levels of heavy metals (Pb, Cu, Cd and zinc) were assessed in their leaves. Chlorophyll and carotenoid contents were determined by absorption spectrometry, while the metal accumulation index (MAI) was used to determine the total metal accumulation capacity of the tree species. We observed a reduction in photosynthetic pigments in the leaf samples from the polluted site. Ficus platyphylla had the maximum reduction in total chlorophyll (49.34%), whereas Terminalia catappa recorded the lowest reduction (33.88%). Similarly, the largest decrease (31.58%) of carotenoid content was found in Terminalia catappa trees and the lowest in Polyalthia longifolia (16.67%). The Polyalthia longifolia, Ficus platyphylla and Terminalia catappa leaf samples collected at the polluted site recorded a higher ratio of chlorophyll a/b. Heavy metal (Cu, Pb, Zn and Cd) accumulation in leaf samples was higher in the polluted site than in the control, as expected. The highest metal MAI value was recorded in Mangifera indica (5.35) followed by Polyalthia longifolia with 4.30. The findings from this study specifically demonstrate that air contamination induced by vehicles decreases the level of photosynthetic pigments in trees subjected to roadside emissions. It is clear that both chlorophyll a/b and chlorophyll/carotenoid ratios will act as very useful stress-level markers. Elevated heavy metal levels in the tree species along arterial roadsides indicate that they serve as heavy metals sink. The change in MAI resulting from different pollution burden is an indication that the removal capabilities of the tree species differ from each other. We therefore suggest M. indica and P. longifolia as potential species to be used in air pollution reduction plans in the city.


2012 ◽  
Vol 425 ◽  
pp. 262-270 ◽  
Author(s):  
Elisa Gamalero ◽  
Patrizia Cesaro ◽  
Angela Cicatelli ◽  
Valeria Todeschini ◽  
Chiara Musso ◽  
...  

1958 ◽  
Vol 36 (2) ◽  
pp. 175-183 ◽  
Author(s):  
A. W. Ghent

The heads of feeding larvae of the jack pine sawfly are consistently oriented towards the needle tips. This orientation is not obtained from the apically-directed needle teeth, and is found to be independent of gravity and of the flexibility of the foliage. Though light can act to disrupt the orientation, larvae adopt the orientation in darkness so that light cannot be postulated as an essential directive stimulus. The behavior is identified as a "free-end" response, and possible underlying mechanisms are discussed.


1953 ◽  
Vol 46 (4) ◽  
pp. 703-703 ◽  
Author(s):  
Daniel M. Benjamin ◽  
Norbert B. Underwood
Keyword(s):  

1963 ◽  
Vol 41 (2) ◽  
pp. 227-235 ◽  
Author(s):  
L. C. O'Neil

An investigation of the radial growth of jack pine (Pinus banksiana Lamb.) defoliated by the Swaine jack-pine sawfly (Neodiprion swainei Midd.) disclosed that growth rings were discontinuous and missing in cross-sectional disks from severely damaged trees. In young and open-grown trees with dead tops, the incidence of such deficiencies in radial growth was especially high in disks from upper regions of the stems, in the vicinity of the dead tops; radial growth was suspended for 1 year and subsequently resumed in disks from the lower regions of some stems. Cambial inactivity was more generalized in trees from an old and dense stand and it was detected in disks representing major portions of some of the stems sampled; the death of some trees followed 2 to 6 years of cambial inactivity in disks cut at various heights along their entire stems. Growth deficiencies in the young stand were clearly effects of severe sawfly defoliation. Data from the old, dense stand indicated that sawfly defoliation had perhaps merely hastened the gradual deterioration of the stand in which intertree competition was intense.


2017 ◽  
Vol 245 ◽  
pp. 325-331 ◽  
Author(s):  
Ravi R. Sonani ◽  
Stuti Patel ◽  
Bela Bhastana ◽  
Kinnari Jakharia ◽  
Mukesh G. Chaubey ◽  
...  

2021 ◽  
Author(s):  
Kim Vertacnik ◽  
Danielle Herrig ◽  
R Keating Godfrey ◽  
Tom Hill ◽  
Scott Geib ◽  
...  

A central goal in evolutionary biology is to determine the predictability of adaptive genetic changes. Despite many documented cases of convergent evolution at individual loci, little is known about the repeatability of gene family expansions and contractions. To address this void, we examined gene family evolution in the redheaded pine sawfly Neodiprion lecontei, a non-eusocial hymenopteran and exemplar of a pine-specialized lineage evolved from angiosperm-feeding ancestors. After assembling and annotating a draft genome, we manually annotated multiple gene families with chemosensory, detoxification, or immunity functions and characterized their genomic distributions and evolutionary history. Our results suggest that expansions of bitter gustatory receptor (GR), clan 3 cytochrome P450 (CYP3), and antimicrobial peptide (AMP) subfamilies may have contributed to pine adaptation. By contrast, there was no evidence of recent gene family contraction via pseudogenization. Next, we compared the number of genes in these same families across insect taxa that vary in diet, dietary specialization, and social behavior. In Hymenoptera, herbivory was associated with large GR and small olfactory receptor (OR) families, eusociality was associated with large OR and small AMP families, and--unlike investigations among more closely related taxa--ecological specialization was not related to gene family size. Overall, our results suggest that gene families that mediate ecological interactions may expand and contract predictably in response to particular selection pressures, however, the ecological drivers and temporal pace of gene gain and loss likely varies considerably across gene families.


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