scholarly journals AN ANALYSIS OF THE MODE OF GENE ACTION AFFECTING PUPA WEIGHT IN TRIBOLIUM CASTANEUM

Genetics ◽  
1975 ◽  
Vol 79 (2) ◽  
pp. 219-229
Author(s):  
R Goodwill

ABSTRACT Triple-testcross experiments (Kearsey and Jinks 1968) were employed to investigate the mode of gene action affecting pupa weight in Tribolium castaneum. Their experimental design involves two inbred lines, the F1 progeny and a segregating population derived from the cross of the inbred lines. In the present experiments, four segregating populations were used. These populations included the F2 generation, a select line (SEL) and two relaxed select lines (RSI and RSII). In addition, all possible reciprocal crosses were made among the RSI, RSII, and SEL populations. It was observed that: (1) additive, dominant and epistatic gene effects all made significant contributions to the pupa weight of the progeny from all four segregating populations; (2) there was no evidence of either accumulation of epistasis as a result of selection in the SEL population or decline in epistasis as a result of removing selection pressure from the RSI and RSII populations; and (3) significant negative heterosis and maternal effects contributed to the pupa weight of the crossbred progeny of the RSI, RSII and SEL populations.

1989 ◽  
Vol 37 (6) ◽  
pp. 609 ◽  
Author(s):  
NG Ehiobu ◽  
ME Goddard

Three crosses among inbred lines of Drosophila melanogaster generated by eight generation full-sib mating, three Australasian population crosses, and two Australian/English population crosses were raised to the F2 generation, to examine evidence of hybrid breakdown. Inbred line crosses produced F2 generations that retained, on average, 54% of the F1 heterosis, which was not significantly different from the retention of 50% F1 heterosis expected under a dominance model of heterosis. Australasian population crosses produced F2 generations with significantly less than 50% of the F1 heterosis, while crosses between Australian and English populations produced a F2 generation that generally performed worse than midparent purebred populations. These results imply epistatic gene action. Because inbred lines contain random combinations of genes, recombination does not necessarily produce hybrid breakdown. However, in crosses between natural populations, recombination is likely to disrupt co-adapted gene combinations leading to poor F2 performance. Populations which rarely exchange migrants are more likely to have alternative gene combinations and to show hybrid breakdown than populations which regularly exchange migrants. The implications of these findings for livestock crossbreeding programs is discussed.


1966 ◽  
Vol 19 (6) ◽  
pp. 1061 ◽  
Author(s):  
EJ Eisen ◽  
BB Bohren ◽  
HE Mckean

The diallel cross has been used frequently in plant experiments to partition the genetic variation into general and specific combining abilities of inbred lines. The statistical models developed for analysis of diallel crosses in plants have been used in a number of studies of diallel crosses in mammals and poultry, without due consideration to the presence and effect of the sex chromosomes.


1998 ◽  
Vol 21 (1) ◽  
pp. 87-92 ◽  
Author(s):  
Claudia E. Lange ◽  
Luiz C. Federizzi ◽  
Fernando I.F. Carvalho ◽  
Ana L.C. Dornelles ◽  
Cristine L. Handel

The genetic bases of in vitro organogenesis and precocious germination of embryos in immature wheat embryo culture were investigated using six Brazilian genotypes and their F1, F2, BC1F1 and BC2F1 generations in a generation means analysis. Four parents and one set of F1’s were also analyzed in a diallel experiment. The results indicated a complex gene action controlling both traits, with additive, dominant and epistatic effects. High broad sense heritability values were found, indicating genetic determination. Considering the complexity of gene control, genetic gain could be achieved by selecting for the traits in advanced generations of the segregating population. Low correlation values between organogenesis, precocious germination, regeneration and somatic embryogenesis (data shown in a previous report) indicated the possibility of obtaining recombinant genotypes.


Author(s):  
Andreea Daniela ONA ◽  
Ioan HAȘ ◽  
Ivan ILARIE ◽  
Voichița HAȘ ◽  
Nicolae TRITEAN ◽  
...  

In the last 40 years, pre-breeding works induced, in more and more centers of maize breeding, full-sib reciprocal recurrent selection programmes to identify some heterotic pairs which can be sources for obtaining performance inbred lines. The aim is to identify the heterotic pairs with the best results according to the yield potential of maize, the breaking and falling resistance, and the grains moisture at the harvesting time. The creation programme of A and B composite population started at ARDS Turda in 1985. Inside of A composite came the next inbred lines: B73, A632, M117, TC209, T291, being from the B SSS heterotic group, and inside of B composite came the inbred lines Mo17, C103, TC 208, T248, W633, appreciated by us or being related to Lancaster Sure Crop heterotic group. The experimentation was done in two orientation comparative cultures, each one with 49 variants, in 4 repetitions; the comparative culture was a balanced quadratic grid of 7x7 type. From each culture were chosen the first six variants, which were evaluated according to the next characters: production potential, breaking and falling resistance, grains moisture at harvest. The presented results are a part from the second cycle of full-sib reciprocal recurrent selection. Test crosses and self-pollinations were made on plants from the two composites which had two cobs; on the first cob from A Composite realised the cross with the corresponding plant from the B Composite, and from the plant panicle of the B Composite was collected pollen to pollinate the chosen plant from the A Composite. At the both plants from the crossing, the second cob was self-pollinated and kept in reserve until 2010, when the test crosses was experimented and were selected the pairs with the best results according to the above characters. Using the full-sib reciprocal recurrent selection, we can successfully harnessing, simultaneously, the additive and non-additive gene effects.


Author(s):  
Alireza Haghighi Hasanalideh ◽  
Mehrzad Allahgholipour ◽  
Ezatollah Farshadfar

This study was undertaken to assess the combining ability of 6 rice varieties, for viscosity parameters and determining gene action controlling Rapid Visco Analyser (RVA) characters. F2 progenies derived from a 6×6 half diallel mating design with their parents were grown in a randomized complete block design with three replications at the research farm of Rice Research Institute of Iran (RRII) in 2015. The diallel analysis by Griffing`s method indicated the involvement of additive and non-additive gene actions controlling RVA traits. For traits PV and FV RI18447-2 and IR50 were the best combiners for increasing and decreasing, respectively. Deylamani and IR50 were the best combiners for increasing and decreasing BV, respectively. Beside, due to more portion of non-additive gene action in controlling trait SV, The Gilaneh × RI18430-46, and Deylamani × RI18430-46 crosses were the best for increasing and decreasing SV, respectively. The high estimates of broad sense heritability and narrow sense heritability for BV and FV, indicated the importance of additive effects in expression of these traits. Therefore, selection base breeding methods will be useful to improve these traits and selection in the early generations could be done to fix the favourable genes. Low estimate of narrow sense heritability for SV revealed that non-additive gene effects play important role in controlling setback viscosity. So, hybrid base breeding methods will be useful to improve this trait.


1962 ◽  
Vol 42 (4) ◽  
pp. 628-634 ◽  
Author(s):  
Edwin E. Gamble

Six inbred lines of corn and their F1’s, F2’s, and backcrosses were tested at two locations in each of 2 years. The population means obtained were used to estimate additive, dominance, additive × additive, additive × dominance, and dominance × dominance gene effects for six quantitative attributes.Variance components of cross × environment interactions indicated the presence of major interactions of gene effects with environments. The cross × year interactions were of major importance but the cross × location interactions were of minor importance. Additive gene effects appeared to be the most constant over environments followed by additive × dominance gene effects. The remaining types of gene effects indicated very little stability over environments for most of the attributes studied. Estimates of gene effects were most constant over environments for ear diameter in corn while yield, plant height, and seed weight showed little or no stability of the estimates of the gene effects.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1625
Author(s):  
Innocent Iseghohi ◽  
Ayodeji Abe ◽  
Silvestro Meseka ◽  
Wende Mengesha ◽  
Melaku Gedil ◽  
...  

Vitamin A deficiency (VAD) is a serious problem in sub-Saharan Africa (SSA) and other parts of the world. Understanding the effect of marker-based improvement (MARS) of two maize synthetics (HGA and HGB) representing different heterotic groups on their agronomic performance, carotenoid content, and combining abilities could help identify suitable sources to develop divergent inbred lines for optimizing heterosis. This study involved three selection cycles each of the two synthetics and their nine varietal-cross hybrids together with a released check variety was conducted across four diverse locations in Nigeria in 2018 and 2019. Environment and hybrid effects were significant on grain yield and other agronomic traits as well as provitamin A content and other carotenoids. Genetic improvement per cycle of MARS in the parental synthetics was 15% for provitamin A, 25% for β-carotene and 26% for lutein in HGA and 4% for grain yield, 3% for zeaxanthin and 5% for α-carotene in HGB. Grain yield and agronomic traits of the two maize synthetics were controlled by additive and non-additive gene effects, while provitamin A content and other carotenoids were mainly controlled by additive gene effects. Some selection cycles which were high in grain yield and provitamin A content were identified as potential sources of new and divergent maize inbred lines in maize breeding programs. Some varietal-cross hybrids expressed significant mid-parent heterosis for grain yield and moderate mid-parent heterosis for provitamin A, β-carotene and xanthophylls. These hybrids could be commercialized at reasonable prices to small-scale farmers in rural areas that are most affected by vitamin A deficiency.


2007 ◽  
Vol 20 (2) ◽  
pp. 23-30 ◽  
Author(s):  
Z. I. Sarker ◽  
A. K. M. Shamsuddin ◽  
R. Ara

Estimates of gene action for lodging related traits at Wheat Research Center during 1999-2002 in three crosses of wheat showed different genetic control of the traits among the crosses. For almost all traits, additive or dominance effects or both components were significant in either three- or six-parameter model, indicating that both additive and dominance gene effects were operative for different traits contributing to lodging resistance. Although duplicate type of epistasis was also observed for second internode breaking strength, plant height and spikes per plant and grain yield per plant once in different crosses, additive x additive epistasis along with additive gene action for the aforesaid traits would improve selection of the same in the segregating populations. The additive x dominance gene interaction for second internode length, diameter and wall thickness would be useful too for improvement of second internode breaking strength and consequently lodging resistance, as their inheritance and selection in segregating populations would be relatively easier than the traits controlled by completely non-additive genes. For duplicate type of epistasis biparental mating or recurrent selection followed by conventional selection is suggested.DOI: http://dx.doi.org/10.3329/bjpbg.v20i2.17031


2016 ◽  
Vol 8 (11) ◽  
pp. 138 ◽  
Author(s):  
Lawrence Owere ◽  
Pangirayi Tongoona ◽  
John Derera ◽  
Nelson Wanyera

<p>Blast disease is the most important biotic constraint to finger millet production. Therefore disease resistant varieties are required. However, there is limited information on combining ability for resistance and indeed other agronomic traits of the germplasm in Uganda. This study was carried out to estimate the combining ability and gene effects controlling blast disease resistance and selected agronomic traits in finger millet. Thirty six crosses were generated from a 9 × 9 half diallel mating design. The seed from the 36 F<sub>1</sub> crosses were advanced by selfing and the F<sub>2</sub> families and their parents were evaluated in three replications. General combining ability (GCA) for head blast resistance and the other agronomic traits were all highly significant (p ≤ 0.01), whereas specific combining ability (SCA) was highly significant for all traits except grain yield and grain mass head<sup>-1</sup>. On partitioning the mean sum of squares, the GCA values ranged from 31.65% to 53.05% for head blast incidence and severity respectively, and 36.18% to 77.22% for the other agronomic traits measured. Additive gene effects were found to be predominant for head blast severity, days to 50% flowering, grain yield, number of productive tillers plant<sup>-1</sup>, grain mass head<sup>-1</sup>, plant height and panicle length. Non-additive gene action was predominant for number of fingers head<sup>-1</sup>, finger width and panicle width. The parents which contributed towards high yield were <em>Seremi 2</em>, <em>Achaki</em>, <em>Otunduru</em>, <em>Bulo</em> and <em>Amumwari</em>. Generally, highly significant additive gene action implied that progress would be made through selection whereas non-additive gene action could slow selection progress and indicated selection in the later generations.</p>


2018 ◽  
Vol 43 (4) ◽  
pp. 599-609
Author(s):  
ANMS Karim ◽  
S Ahmed ◽  
AH Akhi ◽  
MZA Talukder ◽  
A Karim

Combining ability effects were estimated for grain yield and some other important agronomic traits of maize in a 7×7 diallel analysis excluding reciprocals. The variances for general combining ability (GCA) were found significant for yield, days to pollen shedding, days to silking and ear height while it was found non-significant for plant height and number of kernels/ear. Non-significant general combining ability (GCA) variance for plant height and number of kernels/ear indicates that these two traits were predominantly controlled by non- additive type of gene action. Specific combining ability (SCA) was significant for all the characters except yield and days to silking. Non-significant specific combining ability (SCA) variance for yield and days to silking suggests that these two traits were predominantly controlled by additive type of gene action. Both GCA and SCA variances were found significant only in days to pollen shedding and ear height indicated the presence of additive as well as non additive gene effects for controlling the traits. However, relative magnitude of these variances indicated that additive gene effects were more prominent for all the characters studied except days to silking. Parent BIL95 was the best general combiner for both high yield and number of kernels/ear and parent BML4 for dwarf plant type. Two crosses (BML4× BML36 and BIL114× BIL31) exhibited significant and positive SCA effects for grain yield involved low × average and average × average general combining parents. The range of heterosis expressed by different crosses for grain yield and days to silking was from -65.83 to 21.26 percent and -17.85 to 8.22 percent, respectively.. The better performing three crosses (BIL114×BIL31, BIL138×BIL95 and BIL31×BIL95) can be utilized for developing high yielding hybrid varieties as well as for exploiting hybrid vigour.Bangladesh J. Agril. Res. 43(4): 599-609, December 2018


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