Heterosis and combining ability of American and African cotton cultivars in a low latitude under high-yeild conditions

1971 ◽  
Vol 22 (5) ◽  
pp. 759 ◽  
Author(s):  
NJ Thomson
Keyword(s):  
Combining Ability ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Lint Yield ◽  
Strength Index ◽  
Lint Percentage ◽  
Low Latitude ◽  
Gossypium Hirsutum L ◽  
Boll Weight ◽  
Index Variation

A diallel cross of nine cultivars of Gossypium hirsutum L. (race latifolium), grouped on a basis of origin and staple characteristics into African uplands and American high quality and ordinary quality uplands, was used to examine heterosis and combining ability effects. Heterosis associated with the African cultivars, in combination either with the American cultivars or with each other, at an average of 22 % was approximately double that associated with either American group of cultivars. A number of hybrids significantly outyielded the standard commercial cultivar of the region, Stoneville 7A. The best hybrid yielded 271 kg lint/ha more than Stoneville's yield of 1622 kg lint/ha. This increase was brought about by heterosis in the three yield components: number of bolls, boll weight, and lint percentage. Heterosis was also marked for early height with all groups but was absent or only slight for mature height. No significant heterotic effects were demonstrated for micronaire value or Pressley strength index. Variation due to general combining ability predominated in all traits, particularly for lint yield, number of bolls, boll weight, and mature height. Even when significant, the specific combining ability component of variance was much less than the general combining ability component. All three African cultivars and the ordinary quality American type Stoneville 7A had high general combining ability for lint yield and number of bolls and should be valuable parents for use in a breeding programme. Lint yield in the F1 population was strongly genetically correlated with number of bolls but negatively correlated with boll weight, not associated with lint percentage, and slightly negatively associated with micronaire value and Pressley strength index.

HETEROSIS, COMBINING ABILITY, AND PREDICTED SYNTHETICS FROM A DIALLEL CROSS IN SUNFLOWERS (HELIANTHUS ANNUUS L.)

1966 ◽  
Vol 46 (1) ◽  
pp. 59-67 ◽  
Author(s):  
Eric D. Putt
Keyword(s):  
Helianthus Annuus ◽  
Combining Ability ◽  
Oil Content ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Specific Combining Ability ◽  
Helianthus Annuus L ◽  
The Mean ◽  
Seed Characters ◽  
Mature Weight

Heterosis occurred for the eight plant and seed characters studied. It was most frequent for yield of seed and height of plant. Mean squares for general combining ability (gca) and specific combining ability (sca) were significant (P =.01) for all characters. The estimated components for gca were greater than for sca for days to mature, weight per bushel, and percent oil in the seed; less for height and yield of seed; and essentially the same for days to bloom, diameter of head, and weight per 1000 seeds.The yield of seed and percent oil in the seed, for the highest ranking 100 synthetics that could be composed from the 10 lines, was predicted in F6 assuming 50 and 60% outcrossing between F2 and F6. Virtually all values exceeded the mean performance of four check samples of commercial hybrids. Many exceeded the highest rank check for oil content in the seed. Fourteen of the highest ranking 100 synthetics for yield and 30 for oil content consisted of two or three lines. It was concluded that synthetics can be superior to the present hybrids in heterosis and that desirable synthetics can be made from only a few lines.

COMBINING ABILITY ANALYSIS IN THE CULTIVATED STRAWBERRY

1971 ◽  
Vol 51 (5) ◽  
pp. 377-383 ◽  
Author(s):  
L. P. S. SPANGELO ◽  
R. WATKINS ◽  
C. S. HSU ◽  
S. O. FEJER
Keyword(s):  
Combining Ability ◽  
Plant Density ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Flower Stalk ◽  
Combining Abilities ◽  
Combining Ability Analysis ◽  
Strawberry Cultivars

General and specific combining abilities were analyzed for total, marketable, early, and late yield, and for flower stalk number in a diallel cross of eight strawberry cultivars. Data were recorded from individual seedlings restricted to two runner plants, thereby eliminating variability resulting from differences in plant density. General and specific combining abilities for the five characters were highly significant. Estimates of general combining ability effects taken alone were, in general, of little value in predicting the order of desirability of individual crosses.

GENOTYPE × ENVIRONMENT INTERACTIONS IN SMOOTH BROMEGRASS. I. YIELD

1979 ◽  
Vol 21 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Wai-Koon Tan ◽  
Geok-Yong Tan ◽  
P. D. Walton
Keyword(s):  
Genetic Variation ◽  
Analysis Of Variance ◽  
Combining Ability ◽  
Significant Variation ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Bromus Inermis ◽  
Smooth Bromegrass ◽  
Combining Ability Analysis ◽  
Half Diallel

Twenty-one progenies and the parents of a 7 × 7 half diallel cross of smooth bromegrass (Bromus inermis Leyss.) were evaluated at four locations in Alberta in each of two years, for genetic variation and genetic by environment interactions in the expression of their yield potentials. Years, locations and their interactions were highly significant in the combined analysis of variance. Combining ability analysis revealed that general combining ability (GCA) and specific combining ability (SCA) were both important in the expression of yield, including spring, fall and annual yield, whereas GCA was more important than SCA for yield per area. Although the genotype × environment interactions were all highly significant, variation accounted for by combining ability effects was generally higher than the interaction effects of GCA and SCA respectively, with environments. High average GCA effects for spring, fall and annual yield were demonstrated for the clones UA5, UA9 and B42. These together with the high average SCA effects suggested that the three clones could be included in a synthetic to develop high yielding cultivars. The results suggested that recurrent selections involving multi-location and multi-year testing seems necessary in breeding for high yielding bromegrass cultivars in Alberta.

Inheritance of Resistance to Cercospora arachidicola and Cercosporidium personatum in Six Virginia-type Peanut Lines1,3

1980 ◽  
Vol 7 (1) ◽  
pp. 4-9 ◽  
Author(s):  
Julia L. Kornegay ◽  
M. K. Beute ◽  
J. C. Wynne
Keyword(s):  
Combining Ability ◽  
Leaf Spot ◽  
Resistance Breeding ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Leaf Spot Disease ◽  
Inheritance Of Resistance ◽  
Cercospora Arachidicola ◽  
Cercosporidium Personatum ◽  
Leaf Spots

Abstract The inheritance of resistance to two cercospora leaf-spots, Cercospora arachidicola (early leafspot) and Cercosporidium personatum (late leafspot) in Virginia-type peanuts (Arachis hypogaea L.), was determined using F1 and F2 generations and parental lines from a six parent diallel cross under natural field conditions. Two techniques for rating disease severity were employed. General combining ability, determined from both rating techniques, was significant for both F1 and F2 generations, indicating that resistance to both fungi and tolerance to infection i. e., minimal leaf defoliation, was primarily due to additive genetic effects. The six parents produced offspring with different levels of resistance to both fungi. From the estimates of general combining ability effects, only NC-GP 343 and NC 5 produced progeny resistant to both early and late leaf-spot. NC 3033 was resistant to early leafspot, but susceptible to late leafspot. NC-Ac 3139, Florigiant and NC 2 were resistant to late leafspot, but susceptible to early leaf-spot. Disease indices ranked NC 3033 and NC-GP 343 as, overall, the most resistant of the six lines and the most useful to include in a cercospora leafspots resistance breeding program.

GENERAL AND SPECIFIC COMBINING ABILITY IN SEVEN INBRED STRAWBERRY LINES

1968 ◽  
Vol 10 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Lewis E. Aalders ◽  
Donald L. Craig
Keyword(s):  
Genetic Variation ◽  
Powdery Mildew ◽  
Combining Ability ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Specific Combining Ability ◽  
Additive Genetic Variation

Seedlings of a diallel cross of seven strawberry inbreds omitting reciprocals were fruited in matted rows. Per acre fruit yields were comparable with leading cultivars, but berry appearance and quality of the hybrids were poor. Differences in resistance to powdery mildew reflected the values of the cultivars from which the inbreds were derived.All four characters studied showed significant general combining ability values, and three of the four showed significant specific combining ability values. These results are consistent with previous findings of considerable amounts of non-additive genetic variation in the strawberry.

Performance of male-sterile stocks of cotton as parents and hybrids

1976 ◽  
Vol 27 (2) ◽  
pp. 243
Author(s):  
NJ Thomson
Keyword(s):  
Male Sterility ◽  
Yield Components ◽  
Diploid Species ◽  
Yield Component ◽  
Lint Yield ◽  
F1 Hybrids ◽  
Male Sterile ◽  
Lint Percentage ◽  
Genomic Changes ◽  
Boll Weight

Two male-sterile lines of G. hirsutum containing G. anomalum or G. arboreum cytoplasm, their respective maintainer lines, and the M8 variety from which the male sterility stocks had been derived, were crossed reciprocally with each of three male fertility-restoring varieties. The F1 hybrids of the four male sterility stocks did not differ significantly in either lint yield or boll numbers. However, significant though small differences occurred in other traits including boll weight, lint percentage, seedling growth and some fibre properties. Pair-wise comparisons between sets of hybrids containing anomalum v. hirsutum, anomalum v. barbadense, arboreum v. hirsutum and arboreum v. barbadense cytoplasms showed that the diploid species cytoplasms did not significantly affect lint yield or the yield components of number of bolls and boll weight, while the other yield component, lint percentage, was only affected in one instance. Significant cytoplasmic differences in other attributes were rare. The recurrent G. hirsutum parent M8 outyielded its sterile derivatives both as a cultivar and as a hybrid parent. The yield decline of the male-sterile stocks was ascribed to nuclear (genomic) changes resulting from strong selection pressure for sterility during their development. It was concluded that, while the production of cotton hybrids from these male-sterile stocks is technically feasible, their practical utility is limited.

PARTIAL DIALLEL CROSS ANALYSIS AMONG THREE BREEDS OF PIG FOR PRODUCTIVE AND REPRODUCTIVE TRAITS

2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Edy Kurnianto ◽  
Mukh Arifin ◽  
Prasetyo Nugroho
Keyword(s):  
Litter Size ◽  
Combining Ability ◽  
Reproductive Traits ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Partial Diallel

Suatu penelitian telah dilakukan untuk mengevaluasi general combining ability (GCA) dan specific cobining ability (SCA) untuk sifat produksi dan reproduksi pada babi. Materi yang digunakan adalah catatan keturunan hasil persilangan tiga bangsa babi (Duroc, Landrace, Yorkshire) sebanyak 573 anak babi yang berasal dari 13 pejantan dan 65 induk. Formula yang digunakan untuk menganalisis parameter adalah Partial Diallel Cross Metode II dari Griffings. Parameters yang diamati pada anak adalah litter size, bobobt lahir, jumlah puting, pertambahan bobot badan (PBB) sebelum dan sesudah sapih dan bobot sapih. Hasil penelitian menunjukkan bahwa GCA Duroc lebih tinggi dibandingkan Yorksire and Landrace, yang nilai GCA untuk litter size, bobot lahir, jumlah puting, jumlah anak pada saat sapih, bobot sapih, PBB sebelum sapih, PBB setelah sapih dan bobot badan pada umur 42 hari masing-masing -0,18; -0,02; -0,52; -0,13; -0,21; -0,01; 0,01 dan 0,03. Persiilangan antara Duroc x Yorkshire menunjukkan SCA paling tinggi untuk bobot lahir (0.30), jumlah puting (3.60), bobot sapih (1.10) dan PBB sebelum sapih (0.04). Persilangan antara Yorkshire x Landrace menghasilkan SCA paling tinggi untuk litter size (2.47), jumlah anak waktu sapih (2.23), PBB sebelum sapih (0.04), PBB setelah sapih (0.06) and bobot badan pada umur 42 hari (2.30). Kesimpulan penelitian ini adalah nilai paling baik untuk GCA ditunjukkan oleh Duroc, sementara itu SCA oleh persilangan antara Yorkshire x Landrace.

Thrips (Thysanoptera: Thripidae) Tolerance in Cotton: Sources and Heritability

1997 ◽  
Vol 32 (4) ◽  
pp. 460-471 ◽  
Author(s):  
Daryl T. Bowman ◽  
Jack C. McCarty
Keyword(s):  
North Carolina ◽  
Gossypium Hirsutum ◽  
Combining Ability ◽  
Genetic Variance ◽  
Additive Genetic Variance ◽  
General Combining Ability ◽  
Sources Of Resistance ◽  
Gossypium Hirsutum L ◽  
F2 Generation ◽  
F1 Generation

Thrips (Thysanoptera: Thripidae) resistance or tolerance in cotton, Gossypium hirsutum L., is often associated with extreme pubescence. This is undesirable because hairy (pubescent) plants tend to have more trash in harvested lint which reduces the price received by growers. Two other possible sources of resistance include gossypol and thick lower epidermal cells, the latter has been found in G. barbadense L. Five G. barbadense genotypes were mated in a North Carolina Design II to 4 upland cultivars to evaluate combining ability. In addition, 90 converted racestocks were screened for tolerance to thrips. Experiments were designed to evaluate tolerance or resistance by comparing plots with and without thrips. Two G. barbadense parents had tolerance to thrips while two upland cultivars also exhibited tolerance. In the F1 generation, general combining ability was significant for thrips damage ratings among the G. barbadense parents. In the F2 generation, all characters exhibited specific combining ability. Thus, non-additive genetic variance predominates measures of thrips tolerance.

DIALLEL ANALYSIS OF CROSSES BETWEEN FLUE-CURED AND BURLEY TOBACCO CULTIVARS

1970 ◽  
Vol 12 (3) ◽  
pp. 484-489 ◽  
Author(s):  
Bronius Povilaitis
Keyword(s):  
Combining Ability ◽  
Diallel Analysis ◽  
Diallel Cross ◽  
General Combining Ability ◽  
The Other ◽  
Additive Effects ◽  
Burley Tobacco ◽  
Total Variability ◽  
Number Of Leaves ◽  
Cross Experiment

The eight tobacco cultivars Delcrest, Hicks Broadleaf, Yellow Gold and Jamaica Wrapper of the flue-cured type and Burley 1, Burley 21, Virginia B29 and Kentucky 12 of the burley type and their crosses and reciprocals were grown in an 8 × 8 diallel-cross experiment. Diallel analyses were completed according to procedures described by Hayman, Griffing and Robinson.The mean squares for general combining ability and for Hayman's a made up a considerably higher proportion of the total variability than the other subdivisions. The variances for special combining ability were in all instances smaller than those for general combining ability, although there were differences in size and in levels of significance between Griffing's and Robinson's methods. The statistic due to additive effects of genes (Hayman's D) was significant for days to flower, height, and number of leaves, and the statistic due to dominance effects significant for days to flower and height. The greatest effect in decreasing the number of days to flower was exhibited by the cultivar Delcrest, and the greatest effect in increasing the number of days to flower was by Yellow Gold and Kentucky 12. Kentucky 12 showed the greatest effect in increasing height and number of leaves.

Genetic analysis of quantitative characters in cigar and pipe tobacco, Nicotiana tabacum. III. Economic indices: grade index, yield, and crop revenue

1983 ◽  
Vol 25 (2) ◽  
pp. 185-189 ◽  
Author(s):  
I. S. Ogilvie ◽  
V. Kozumplik
Keyword(s):  
Nicotiana Tabacum ◽  
Combining Ability ◽  
Diallel Cross ◽  
General Combining Ability ◽  
Specific Combining Ability ◽  
Total Alkaloids ◽  
Nicotiana Tabacum L ◽  
Economic Indices ◽  
Grade Index ◽  
Pipe Tobacco

A diallel cross of four cigar cultivars and one pipe tobacco (Nicotiana tabacum L.) cultivar was analyzed for the following parameters: grade index, yield, crop revenue or index, percentage of nicotine, percentage of total alkaloids, and susceptability to pole rot. The experiment was performed over 3 years. Analysis was done for general combining ability and specific combining ability. General combining ability was greater than specific combining ability for all variables although significant specific combining ability effects were also present for all parameters with the exception of nicotine and total alkaloids. Reciprocal effects were completely absent. The line Pennbel 69 showed a positive general combining ability effect for yield, crop index, and infestation by pole rot and a high negative general combining ability effect for grade index and percentage of nicotine and total alkaloids. Petit Havane showed a complete reverse of general combining ability effects for these parameters while the other three cultivars were intermediate. High positive specific combining ability effects for grade index, yield, and crop index and high negative specific combining ability effects for the percentage of pole rot were shown by crosses of Pennbel 69.

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