EVALUATION OF THE ASSUMPTIONS REQUIRED FOR THE GENETIC INTERPRETATION OF DIALLEL EXPERIMENTS IN SELF-POLLINATING CROPS

1977 ◽  
Vol 57 (4) ◽  
pp. 1185-1191 ◽  
Author(s):  
M. J. SOKOL ◽  
R. J. BAKER

Simulation of two-locus genetic models was used to investigate the effects of gene frequency, non-random association of genes, and epistasis on the interpretation of diallel experiments in self-pollinating crops. It was demonstrated that general combining ability includes effects due to additive, epistatic, and, when gene frequencies are not equal to 0.5, dominance gene action. Similarly, when gene frequencies do not equal 0.5, average heterosis depends upon additive × dominance interaction as well as dominance and dominance × dominance interaction. Negative associations between genes greatly inflate the apparent amount of specific combining ability. These findings cast serious doubt on the utility of diallel analysis for studying the genetics of self-pollinating crops.

HortScience ◽  
2001 ◽  
Vol 36 (7) ◽  
pp. 1315-1317 ◽  
Author(s):  
Yayeh Zewdie ◽  
Paul W. Bosland ◽  
Robert Steiner

The inheritance of capsaicinoid content was studied in five Capsicum pubescens Ruiz & Pav. genotypes using diallel analysis. General combining ability and specific combining ability effects were significant for all capsaicinoids studied, indicating additive and nonadditive gene actions are present. The association of high capsaicinoid contents with high positive general combining ability of the parents also indicates the predominance of additive gene action in capsaicinoid inheritance. Because of the predominant additive gene effect, recurrent selection would be a good breeding method to increase capsaicinoid level in the population studied. Heterosis was observed in hybrids for some of the capsaicinoids, suggesting that F1 hybrids could also be used to increase capsaicinoid content.


Author(s):  
В. В. Ващенко ◽  
О. О. Шевченко

У системі діалельних схрещувань п’яти сортів яч-меню ярого (Донецький 12, Донецький 14, Донецький 15,Прерія, Галактик) установлено особливості генети-чного контролю мінливості ознак: висота рослин,кількість зерен у колосі, маса 1000 зерен у відповід-ності зі співвідношенням варіанс специфічної комбі-наційної здатності (СКЗ) і загальної комбінаційноїздатності (ЗКЗ). Виділено й запропоновано сорти якджерела ознак висота рослин Галактик і Донецький14; кількість зерен у колосі – сорт Прерія; маса 1000зерен – сорт Донецький 15. Виділені зразки з високимі стабільним рівнем комбінаційної здатності запро-поновано використовувати в селекційній роботі. A total of diallel analysis varieties of springbarley Donetskiy 12, Donetskiy 14, Donetskiy 15,Prairie, Galactic set features genetic controlvariability characteristics: plant height, number ofgrains per ear, 1000 grain weight in accordance withthe ratio of variance of specific combining ability(SSI) and general combining ability (ZKZ).Identified and proposed as a source of variety traitsplant height and Donetsk 14, Galactic, the numberof grains per ear sort Prairie, weight of 1000 grainsDonetskiy 15. Samples of high and stable levels ofcombining ability is proposed to use in breedingwork have beeen celected.


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


2018 ◽  
Vol 49 (6) ◽  
Author(s):  
Hammadi & abed

Six inbred lines of maize were crossed in this study by using half – diallel analysis method , during spring season of 2017, to produce fifteen F1 crosses. The parents and crosses were cultivated during fall season of 2017 by using R.C.B.D with three replications to determine heterosis, general and specific combining ability effects and gene action . Significant differences were found among parental and their crosses for all the traits . The results were showed that the hybrid ( Zm - 1× Zm - 5) had the highest heterosis in grain yield.plant-1 (113.4%). The hybrid (ART-B-17x SYN-33) produced highest number rows. ear-1 (17.9) rows, 500 kernel weight (112.9) gm and grain yield.plant-1 (214.7) gm . The values  of  specific combining ability variances were more than the general combining ability variances for all the traits, indicating that non-additive gene action was responsible for inheritance of all the traits. The values of the broad sense heritability for all characters were higher and  average degree of dominance was exceeded one for all the traits . Results indicated that some inbreds could be used in breeding  program to develop single crosses which have  higher grain yield because all the traits  under over dominance gene action


2016 ◽  
Vol 21 (1) ◽  
pp. 9
Author(s):  
RR. SRI HARTATI ◽  
SUDARSONO SUDARSONO

<p>ABSTRAK<br />Perakitan varietas unggul memerlukan informasi daya gabung tetua,<br />baik umum maupun khusus. Tetua dengan daya gabung umum (DGU)<br />tinggi berpotensi menghasilkan varietas sintetis atau komposit. Sementara<br />itu, tetua dengan daya gabung khusus (DGK) tinggi berpotensi<br />menghasilkan varietas hibrida. Tujuan penelitian adalah mengetahui daya<br />gabung tetua jarak pagar yang dapat menghasilkan hibrida atau populasi<br />komposit. Sepuluh tetua, yaitu 1 tetua berdaya hasil rendah, 6 menengah,<br />dan 3 tinggi digunakan dalam persilangan dialel lengkap. Evaluasi<br />dilaksanakan di Kebun Percobaan Balittri Pakuwon Sukabumi, mulai<br />Agustus 2008 sampai Juli 2011 menggunakan Rancangan Acak Kelompok<br />tiga ulangan. Karakter yang diamati yaitu tinggi tanaman, lingkar batang,<br />lebar kanopi, umur mulai berbunga, serta jumlah cabang total, cabang<br />produktif, infloresen, tandan, fruit set, dan buah per tanaman. Analisis<br />dialel menggunakan metode I Griffing. Hasil penelitian menunjukkan ratio<br />ragam DGU dan DGK lebih besar daripada satu ( DGU / DGK &gt; 1) pada<br />semua karakter yang dievaluasi. Tetua 3012-1 dan PT 15-1, yang berdaya<br />hasil tinggi, memiliki DGU tinggi pada karakter umur mulai berbunga,<br />lebar kanopi, serta jumlah cabang total, cabang produktif, infloresen,<br />tandan, dan buah. Tetua PT 33-2, yang berdaya hasil menengah, memiliki<br />DGU tinggi pada karakter umur mulai berbunga, serta jumlah cabang total,<br />cabang produktif, infloresen, dan buah. Sementara itu, tetua 575-3, yang<br />berdaya hasil rendah, memiliki DGU tinggi pada lingkar batang. Tetua PT<br />33-2, 3012-1, dan PT 15-1 berpotensi sebagai penyusun populasi dasar<br />untuk pembentukan varietas sintetik yang cepat berbunga dan berdaya<br />hasil tinggi. Tetua 575-3 berpotensi untuk dirakit sebagai varietas yang<br />memiliki lingkar batang besar dan berbunga lambat.<br />Kata kunci: daya gabung umum, daya gabung khusus, gen aditif,<br />komposit, Jatropha curcas L.</p><p>ABSTRACT<br />General Combining Ability (GCA) and Specific Combining Ability<br />(SCA) are important in creating high yielding varieties. A parent having<br />high GCA is appropriate to produce synthetic or composite varieties, while<br />high SCA is to produce hybrid. The research objective is to find out the<br />information of parents combining ability in Jatropha curcas L. Research<br />was conducted using diallel analysis. Ten genotypes i.e. 1 low yielding<br />parent, 6 medium, and 3 high were used to generate F1 arrays with full<br />diallel analysis. Evaluation was conducted at Indonesian Spice and<br />Industrial Crops Research Institute Experimental Station, using<br />Randomized Block Design from August until July 2011. The observation<br />were plant height, stem girth, canopy width, days to flowering, and<br />number of total branches, productive branches, inflorescences, bunches,<br />fruit set percentages; and fruit per plant. Diallel analysis was using<br />Griffing Model I. Results showed that general variance, each of GCA and<br />SCA ratio, is more than one ( GCA / SCA &gt; 1) in all evaluated characters.<br />High yielding parents of 3012-1 and PT 15-1 exhibited high GCA on days<br />to flowering, canopy width, and number of total branches, productive<br />branches, inflorescences, bunches, and fruits. Medium yielding parents of<br />PT 33-2 exhibited high GCA for days to flowering, number of total<br />branches, productive branches, inflorescences, and fruits. Low yielding<br />genotype of 575-3 exhibited high on stem girth. PT 33-2, 3012-1, and PT<br />15-1 could be used for developing early flowering and high yielding<br />varieties, while 575-3 was suitable for producing big stem girth and late<br />flowering varieties.<br />Key word: general combining ability, specific combining ability, additive<br />gen, composite, Jatropha curcas L.</p>


Author(s):  
Beena Nair ◽  
R. B. Ghorade

A diallel analysis of 36 F<sub>1</sub> and 36 F<sub>2</sub> progenies hybrids along with nine divergent parents were estimated. The general and specific combining ability for selection of potential parents and crosses and to ascertain the nature of gene action operating in inheritance of some important quantitative characters associated with shoot fly resistance. These 36 hybrids were developed by crossing nine diverse parents in <italic>rabi</italic> 2011-12. The results indicated that, IS 18551, IS 2312, SPV 504, Ringni and AKSV 13R showed desirable gca effect for most of the shoot fly resistance traits in F<sub>1</sub> and F<sub>2</sub> diallel progenies. Crosses exhibiting highest positive significant sca effects for almost all the shoot fly resistance traits included CSV 18R X IS 18551, Ringni X AKR MS45B and IS 2312 X IS 18551 in F<sub>1</sub> and F<sub>2</sub> diallel progenies. So these crosses may be forwarded further to develop genotypes with shoot fly resistance.


1980 ◽  
Vol 22 (4) ◽  
pp. 633-640 ◽  
Author(s):  
S. B. Rood ◽  
D. J. Major

A set of eight corn (Zea mays L.) inbreds was studied in a diallel cross over two years and in a growth room to investigate general and specific combining ability for flowering-time. Diallel analysis of days from emergence to flowering revealed a failure of the joint Wr/Vr regression in one of the years, indicating a lack of agreement with the simple additive-dominance model of inheritance. The array position changed across the years and environments, complicating genetic interpretation. Transforming data of flowering-time to cumulative corn heat units (CHU) to flowering gave a better fit. Joint regression was satisfactory and array position was more consistent across years and environments. Dominance was incomplete for low CHU to flowering. Positive (increasing CHU) and negative, as well as dominant and recessive, alleles were in about equal frequencies. Heritability estimates in the broad- and narrow-sense were high. The estimates of general combining ability were higher than the estimates of specific combining ability in all studies.


Bragantia ◽  
2007 ◽  
Vol 66 (1) ◽  
pp. 641-647 ◽  
Author(s):  
José Marcelo Soriano Viana

This study discusses from the theoretical standpoint the analyses of heterosis and combining ability from the partial diallel. Aiming at to investigate the information provided by the genetic parameters, simulation studies were realized. The genetic model adjusted considered one gene, groups of six populations, three degrees of dominance (|d/a| equal to 0.5, 1 and 2, representing partial, complete and overdominance) and random allelic frequencies. For each degree of dominance 50 replications were performed. The model for heterosis analysis does not need to be restricted. The unrestricted model gives the same information as the restricted one. The model for combining ability is restricted. The restrictions of the partial-G2 model of GERALDI and MIRANDA-FILHO do not satisfy the parametric values of the specific combining ability effects. As in the complete diallel analysis, from the theoretical point of view there is no differences between the analysis of heterosis and combining ability. The analysis of differences in gene frequencies among the populations of the two groups is more efficient when it considers the heterosis and not the specific heterosis - or the specific heterosis effects or the effects of specific combining ability - mainly for genes whose frequencies are contrasting in the groups.


Plant Disease ◽  
1997 ◽  
Vol 81 (4) ◽  
pp. 388-394 ◽  
Author(s):  
N. K. Osterbauer ◽  
K. B. Johnson ◽  
S. A. Mehlenbacher ◽  
T. L. Sawyer

Inheritance of resistance to eastern filbert blight, caused by Anisogramma anomala, in European hazelnut (Corylus avellana) was evaluated in the progeny of seven cultivars crossed in 12 combinations. The progeny were subjected to inoculation with A. anomala in the greenhouse and in the field. Three disease responses were measured: disease incidence, number of cankers, and proportion of wood diseased. In both the greenhouse and the field, progeny produced by crossing VR6-28 with three susceptible cultivars segregated 1:1 for complete resistance to eastern filbert blight, confirming a previous report that VR6-28 is heterozygous for a single, dominant resistance gene. Histograms of disease responses in progeny of the remaining six parents showed continuous distributions for all crosses examined. Consequently, these parents were analyzed for general and specific combining abilities for each disease response. In the field, general and specific combining ability were both significant (P < 0.05) for all disease responses, with general combining ability having twice the magnitude of specific combining ability. These results suggest these disease responses are controlled by additive gene action in the cultivars examined, with nonadditive gene action being of some importance. Based on general combining ability values, high levels of partial resistance were transmitted by the pollen parents, Gem and Tonda di Giffoni, and the seed parent, Willamette. Heritability of disease incidence, number of cankers, and proportion of wood diseased were calculated to be 0.21, 0.39, and 0.47, respectively, for this set of nine crosses after the first exposure period in the field. This suggests that it will be possible to use partially resistant parents to breed for hazelnuts exhibiting fewer and smaller cankers.


Author(s):  
Anamika Nath ◽  
S. R. Maloo ◽  
Baudh Bharti ◽  
R. B. Dubey ◽  
Rajani Verma

A diallel method was employed in which eight genotypically diverse lines of mungbean were crossed among themselves in all possible combinations excluding reciprocals. The mean square due to general combining ability (GCA) and specific combining ability (SCA) were significant for all the characters except mean square due to (SCA) for clusters per plant and seed yield per plant indicating importance of both additive as well as non-additive gene action. The estimates of variances due to specific combining ability were higher than general combining ability for all the traits except days to 50 % flowering, primary branches per plant, clusters per plant and seed yield per plant pointed out to be the preponderance of non-additive gene effects in the expression of these characters. Whereas predictability ratios were greater than the value of 0.5 for days to 50 % flowering, primary branches per plant, clusters per plant and seed yield per plant indicating the predominance of additive gene action for these characters. However, predictability ratio exhibited less than 0.5 values for rest of the characters indicating the predominance of non- additive gene action. The good general combiners for seed yield per plant were BM-4, PDM-139, ML-131, and IPM 99-125. The best specific cross combinations wereRMG-344 x RMG-1045, RMG-1035 x RMG-1045 and BM-4 x PDM-139. showed the highest positive significant SCA effect for seed yield per plant. These cross combinations could be utilized for further use in breeding programme for improvement in yield of mungbean.


Sign in / Sign up

Export Citation Format

Share Document