Insect Behaviour As A Factor In Applied Entomology

Author : Charles Gordon Hewitt
Publisher : Forgotten Books
ISBN 13 : 9780260528339
Total Pages : 20 pages
Book Rating : 4.5/5 (283 download)

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Download or read book Insect Behaviour as a Factor in Applied Entomology (Classic Reprint) written by Charles Gordon Hewitt and published by Forgotten Books. This book was released on 2017-11-08 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Insect Behaviour as a Factor in Applied Entomology The realization that in the ultimate control of the gipsy moth in North America, the silvicultural aspect of the problem must receive serious consideration is an indication of the importance of chemo tropism in the control of this pest. The elimination of favored food plants and the substitution of unfavored species such as pine are meas ures largely based on the principle of food attraction, that is, of chemo tropism, and should be so regarded. Enticing and suggestive as the subject of chemotropism has been shown to be, we must pass on to the next tropic reaction, namely, thermotropism. In temperature we encounter an environmental influence which is as far-reaching as it is universal in its relation to insect behaviour, and while it is inseparably associated with other factors, especially that of moisture which we shall consider later, it is in itself sufficiently potent to determine the range of insect activity in both time and space. The relation of temperature to the distribution of insects is too well known to require demonstration by examples. Merriam's laws of temperature control, namely: (1) that animals and plants are restricted in northward distribution by the total quantity of heat during the season of growth and reproduction, and (2) that animals and plants are restricted in southward distribution by the mean temperature of a brief period during the hottest part of the year, in general, hold true in regard to insect distribution. The importance of determining the optimum temperatures for the repro duction and development of different insects has been realized by a number of investigators, although their conclusions have sometimes been defective through neglect to take into consideration the coopera tive effect of other environmental factors such as humidity. The influence of temperature on development is illustrated very strikingly in the Aphides. For example, Ewing has recently found that a con stant temperature of 90° F. Is sufficient to prevent completely the development of A phis avenaz and that the optimum temperature for the production of Wingless agamic forms of this species is about 65° F these forms only being produced at a mean average daily temperature of about 65° F. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.