Some Cytogenetic Methods for the Investigation of Insect Chromosomes and Their Implications for Research in Systematic Entomology

Abstract

Abstract:The use of karyological studies in insects is of considerable significance. However, chromosome karyotyping has been hampered principally by: 1) the minute size of many insects, 2) the recovery of suitable tissues, 3) the small number of cells adequate for analyses 4) the smallness of the chromosomes in some groups, 5) the difficulty in obtaining satisfactory numbers of well-spread or dispersed metaphases, and 6) the determination of the best time of the year to carry out chromosome preparations using freshly collected material because the life history of many insects is still not well-known. Many attempts have been made to reduce these difficulties by developing novel karyological methods. These procedures can yield chromosome preparations applicable to a wide variety of insects. In this paper, we outline techniques for preparation and observation of chromosomes from insect cells. Also, implications of chromosome techniques on insect systematics are discussed.