Acclimation and Selection for Increased Resistance to Thermal Stress in Drosophila buzzatii

Abstract Direct selection for increased resistance to a heat shock (41.9° for 90 min) was carried out using two replicate lines of Drosophila buzzatii that were derived from a large base population. Selected individuals were first acclimated to high temperature before selection, while control individuals were acclimated but not selected, and selection was performed every second generation. Resistance to heat shock with acclimation increased in selected lines. Without acclimation, a correlated smaller increase in heat-shock resistance was suggested. Survival of males was higher than that of females in all lines when tested with acclimation, but with direct exposure to high temperatures, survival of females was greater than that of males both in selection and control lines but not in the base population. From analysis of reciprocal cross progeny between lines, one selection line was found to possess a dominant autosomal factor that significantly increased resistance of males much more than resistance of females. Also suggestive was recessive traits on the X chromosome in both selection lines that increased thermotolerance. No cytoplasmic effects were found. After accounting for other effects, survival of F1 flies was intermediate, suggesting that additive variation is present for one or more of the autosomes.

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Selection for Heat-Shock Resistance in Larval and in Adult Drosophila buzzatii: Comparing Direct and Indirect Responses

Evolution ◽

10.2307/2410704 ◽

1996 ◽

Vol 50 (6) ◽

pp. 2354 ◽

Cited By ~ 28

Author(s):

Volker Loeschcke ◽

Robert A. Krebs

Keyword(s):

Heat Shock ◽

Drosophila Buzzatii ◽

Shock Resistance ◽

Selection For ◽

Adult Drosophila

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SELECTION FOR HEAT-SHOCK RESISTANCE IN LARVAL AND IN ADULT DROSOPHILA BUZZATII : COMPARING DIRECT AND INDIRECT RESPONSES

Evolution ◽

10.1111/j.1558-5646.1996.tb03623.x ◽

1996 ◽

Vol 50 (6) ◽

pp. 2354-2359

Author(s):

Volker Loeschcke ◽

Robert A. Krebs

Keyword(s):

Heat Shock ◽

Drosophila Buzzatii ◽

Shock Resistance ◽

Selection For ◽

Adult Drosophila

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Polygenic and single gene responses to selection for resistance to diazinon in Lucilia cuprina.

Genetics ◽

10.1093/genetics/130.3.613 ◽

1992 ◽

Vol 130 (3) ◽

pp. 613-620 ◽

Cited By ~ 6

Author(s):

J A McKenzie ◽

A G Parker ◽

J L Yen

Keyword(s):

Resistant Strain ◽

Single Gene ◽

Natural Populations ◽

Susceptible Strain ◽

Selection Line ◽

Base Population ◽

Gene Response ◽

Biochemical Profiles ◽

Resistant Strains ◽

Selection For

Abstract Following mutagenesis with ethyl methanesulfonate, selection in a susceptible strain with a concentration of the insecticide diazinon (0.0004%, w/v) above that required to kill 100% of the susceptible strain, the LC100 of that strain, resulted in a single gene response. The resultant four mutant resistant strains have equivalent physiological, genetical and biochemical profiles to a diazinon-resistant strain derived from a natural population and homozygous for the Rop-1 allele. Modification of the microsomal esterase E3 is responsible for resistance in each case. The Rop-1 locus maps approximately 4.4 map units proximal to bu on chromosome IV. Selection within the susceptible distribution, at a concentration of diazinon [0.0001% (w/v)] less than the LC100, resulted in a similar phenotypic response irrespective of whether the base population had been mutagenized. The responses were polygenically based, unique to each selection line and independent of Rop-1. The relevance of the results to selection for insecticide resistance in laboratory and natural populations is discussed.

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Studies on the Scutellar Bristles of Drosophila melanogaster. IV. Selection for Low Bristle Number in Oregon-RC Wild-type Lines

Australian Journal of Biological Sciences ◽

10.1071/bi9840277 ◽

1984 ◽

Vol 37 (4) ◽

pp. 277

Author(s):

BL Sheldon ◽

M K Evans

Keyword(s):

Recessive Gene ◽

Population Level ◽

Initial Response ◽

The Other ◽

Selection Line ◽

Base Population ◽

Wild Type ◽

Threshold Phenomenon ◽

Bristle Number ◽

Selection For

Results are presented of 130-145 generations of selection for low scutellar bristle number in four lines of D. melanogaster derived directly from an Oregon-RC wild-type stock and in one derived from an Oregon-RC line selected for low sternital bristle number. The most rapid initial response and the lowest mean scutellar bristle number ultimately reached, just below 2 bristles, occurred in a line in which the response was due to a new recessive gene located at approximately 17�4 on the X chromosome. Three of the other four lines reached a plateau just above a mean of 2 bristles after different patterns of response. These plateaux reflected a new canalization or threshold phenomenon at 2 bristles in these lines. The remaining line reached a mean of about 2� 5 bristles after some 50 generations and remained at that level or slightly higher thereafter, but had no indication of canalization at 2 bristles. Two relaxed lines were derived from each selection line at different times and showed variable patterns of regression towards the base population level.

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STUDIES ON THE SCUTELLAR BRISTLES OF DROSOPHILA MELANOGASTER. II. LONG-TERM SELECTION FOR HIGH BRISTLE NUMBER IN THE OREGON RC STRAIN AND CORRELATED RESPONSES IN ABDOMINAL CHAETAE

Genetics ◽

10.1093/genetics/71.4.567 ◽

1972 ◽

Vol 71 (4) ◽

pp. 567-595

Author(s):

B L Sheldon ◽

M K Milton

Keyword(s):

Population Level ◽

Direct Selection ◽

Correlated Response ◽

Selection Line ◽

Wild Type ◽

Correlated Responses ◽

Bristle Number ◽

Dominance Level ◽

The Mean ◽

Selection For

ABSTRACT Results are presented of 135 generations of selection for high scutellar bristle number in two lines M and M3 derived from the same original mating of one female with 5 bristles by one male with 4 bristles, the latter being the wild-type canalised phenotype. Results are also given of two relaxed lines per line and of a reselection line M2 derived from the first relaxed line of line M which had regressed almost to base population level. The effect of introducing the sc1 allele into the M and M3 selected backgrounds was studied at generations 39–44. At the end of selection the effect of an extra dose of sc+ was also studied in males of all selected backgrounds. The correlated responses in abdominal bristles were followed in all lines.—Considering their common origin, the selection lines differed markedly in pattern of scutellar response and in most other aspects observed, namely correlated responses in abdominals and p.c. scutellars, sex differences, and behaviour on relaxation. Selection limits for scutellar bristles in lines M and M2 were equal to or greater than the most extreme reported in the literature.—The probit span of the canalised 4 bristle class decreased in each selection line as the mean scutellar bristle number increased, and increased again in the relaxed lines as the mean bristle number decreased. In the context of an hypothesis that canalisation at 4 bristle is due to regulation of the scute locus, this result is now interpreted as being due mainly to selection for poor regulators of sc+, in contrast to a previous interpretation that only the minor gene background was altered by selection, the canalisation (regulation) genotype not being affected.—Introducing the sc 1 allele into the selected backgrounds M and M3 showed a reduced effect on sc 1 flies compared with sc+ flies, and an interaction of sc 1 and sc+ with selected background. sc 1 flies had about the same number of bristles in both backgrounds though the mean of sc+ flies in line M was about 3? higher than in line M3. Dominance of sc+ to sc 1 was reduced slightly in M3. However, the effect of an extra dose of sc+ at the end of selection was about the same as in unselected in all lines, so the first or dominance level of regulation of the scute locus was not significantly affected by selection, though the second or canalisation level of regulation was.—A large positive correlated response in abdominal bristles occurred in all lines. The response in line M was about twice that in M2 and M3 and was in fact as large as can be obtained from direct selection on abdominals. In line M some genes may have been selected with a proportionately greater effect on abdominals than on scutellars. This is supported by the further observation in line M that the abdominal scores of flies with particular scutellar bristles scores increased as the scutellar mean increased. An attempt was made to apply to these results Rendel's (1962) model of competition between scutellars and abdominals for common bristle-making resources. This could not be done satisfactorily mainly because the assumptions in the model about the similarity of effects in scute and wild-type flies were not met in the present material.

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SELECTION FOR REDUCED CROSSING OVER IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/76.3.447 ◽

1974 ◽

Vol 76 (3) ◽

pp. 447-451

Author(s):

Nasr F Abdullah ◽

Brian Charlesworth

Keyword(s):

Drosophila Melanogaster ◽

Regression Coefficient ◽

Selection Line ◽

Crossing Over ◽

Base Population ◽

The Third ◽

Significant Difference ◽

Selection For ◽

Significant Regression ◽

Recombination Value

ABSTRACT Selection was practiced for reducing crossing over between the third chromosome genes Sb and H2 of Drosophila melanogaster, the method employed was to select the repulsion double heterozygotes Sb+/+H2 every generation. Two replicate selection lines were maintained. After 24 generations of selection, Line 1 showed no significant difference from the control, although the regression of recombination value on generation was significant. In generation 20, Line 2 had a significantly lower recombination value than the control, as well as having a highly significant regression coefficient. No chromosome rearrangements were involved in the response. It was concluded that there was substantial genic variability in the frequency of crossing over between Sb and H2 in the base population.

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ESTIMASI NILAI HERITABILITAS BOBOT IKAN MAS VARIETAS PUNTEN DALAM PROGRAM SELEKSI INDIVIDU

Jurnal Riset Akuakultur ◽

10.15578/jra.11.3.2016.217-223 ◽

2016 ◽

Vol 11 (3) ◽

pp. 217

Author(s):

Estu Nugroho ◽

Budi Setyono ◽

Mochammad Su’eb ◽

Tri Heru Prihadi

Keyword(s):

Body Weight ◽

Selection Response ◽

Base Population ◽

Breeding Programs ◽

Male And Female ◽

Body Weight Trait ◽

Population Selection ◽

Selection For ◽

Weight Trait ◽

Selection Of

Program pemuliaan ikan mas varietas Punten dilakukan dengan seleksi individu terhadap karakter bobot ikan. Pembentukan populasi dasar untuk kegiatan seleksi dilakukan dengan memijahkan secara massal induk ikan mas yang terdiri atas 20 induk betina dan 21 induk jantan yang dikoleksi dari daerah Punten, Kepanjen (delapan betina dan enam jantan), Kediri (tujuh betina dan 12 jantan), Sragen (27 betina dan 10 jantan), dan Blitar (15 betina dan 11 jantan). Larva umur 10 hari dipelihara selama empat bulan. Selanjutnya dilakukan penjarangan sebesar 50% dan benih dipelihara selama 14 bulan untuk dilakukan seleksi dengan panduan hasil sampling 250 ekor individu setiap populasi. Seleksi terhadap calon induk dilakukan saat umur 18 bulan pada populasi jantan dan betina secara terpisah dengan memilih berdasarkan 10% bobot ikan yang terbaik. Calon induk yang terseleksi kemudian dipelihara hingga matang gonad, kemudian dipilih sebanyak 150 pasang dan dipijahkan secara massal. Didapatkan respons positif dari hasil seleksi berdasarkan bobot ikan, yaitu 49,89 g atau 3,66% (populasi ikan jantan) dan 168,47 g atau 11,43% (populasi ikan betina). Nilai heritabilitas untuk bobot ikan adalah 0,238 (jantan) dan 0,505 (betina).Punten carp breeding programs were carried out by individual selection for body weight trait. The base population for selection activities were conducted by mass breeding of parent consisted of 20 female and 21 male collected from area Punten, eight female and six male (Kepanjen), seven female and 12 male (Kediri), 27 female and 10 male (Sragen), 15 female and 11 male (Blitar). Larvae 10 days old reared for four moths. Then after spacing out 50% of total harvest, the offspring reared for 14 months for selection activity based on the sampling of 250 individual each population. Selection of broodstock candidates performed since 18 months age on male and female populations separately by selecting based on 10% of fish with best body weight. Candidates selected broodstocks were then maintained until mature. In oder to produce the next generation 150 pairs were sets and held for mass spawning. The results revealed that selection response were positive, 49.89 g (3.66%) for male and 168.47 (11.43%) for female. Heritability for body weight is 0.238 (male) and 0.505 (female).

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