Linkage relationships among five enzyme-coding gene loci in the copepod Tigriopus californicus: A genetic confirmation of achiasmatic meiosis

ABSTRACT Forty-eight useful new mutations of S. commune were obtained by mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine. Their requirements and meiotic linkage relationships to each other and previously mapped areas were investigated. Several of these new mutations were incorporated into diploid strains so that the diploids contained at least one marker on every linkage group. Analysis of somatic recombination in these diploids indicated that each meiotic linkage group corresponded to an independent chromosome.

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Linkage relationships of HLA and a familial chromosome 6 inversion (pter→p23::q23→p23::q23→qter): lack of dose effect in duplication-deficient offspring

Cytogenetic and Genome Research ◽

10.1159/000130987 ◽

1978 ◽

Vol 22 (1-6) ◽

pp. 418-420 ◽

Cited By ~ 3

Author(s):

R.E. Magenis ◽

J. Chamberlin ◽

K. Overton ◽

E. Lovrien

Keyword(s):

Dose Effect ◽

Chromosome 6 ◽

Linkage Relationships

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Influence of the Insecticide Diflubenzuron (Dimilin) on the Growth of Marine Diatoms and a Harpacticoid Copepod in Culture

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f85-158 ◽

1985 ◽

Vol 42 (7) ◽

pp. 1272-1277 ◽

Cited By ~ 6

Author(s):

N. J. Antia ◽

P. J. Harrison ◽

D. S. Sullivan ◽

T. Bisalputra

Keyword(s):

Skeletonema Costatum ◽

Harpacticoid Copepod ◽

Adult Survival ◽

Thalassiosira Weissflogii ◽

Marine Diatoms ◽

Tigriopus Californicus ◽

Per Se ◽

Juvenile Development ◽

Cyclotella Cryptica ◽

Injurious Effects

Diflubenzuron (Dimilin) was tested, in the concentration range 0.1–5000 μg∙L−1, for possible injurious effects on the growth and photosynthesis of three chitin-producing (Thalassiosira weissflogii, T. norden-skioldii, Cyclotella cryptica) and one nonchitinaceous (Skeletonema costatum) diatoms. For comparison, the effects of the pesticide were also examined on adult survival and juvenile development of the harpacticoid copepod Tigriopus californicus. While the development of the copepod was hindered at concentrations of the order of 1–10 μg∙L−1, the diatoms were barely affected by Dimilin even at the highest concentration tested (5 mg∙L−1). We conclude that Dimilin acts specifically on insects and crustaceans as a larvicide by interfering with chitin deposition into cuticles during juvenile development through ecdysis. The lack of effect from Dimilin on the chitin-producing diatoms has suggested that the insecticide may not inhibit chitin biosynthesis per se as was previously believed, but that it presumably deregulates one or more of the larval postsynthetic processes responsible for chitin integration into cuticles.

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