Combining Ability Analysis Research Articles

Combining Ability Analysis for Seed Yield and Attributing Traits in Linseed (Linum usitatissimum L.)

A complete set of 79 entries comprising of twelve parents, their 66 F1s and one check RLC-92 were evaluated during rabi 2020-21 at two locations i.e., ARS, Dahod, and BTRS, Anand, under two dates of sowing i.e., 2nd fortnight of October and 1st fortnight of November. The present study aimed to investigate the combining ability analysis over environments for seed yield and attributing traits in linseed (Linum usitatissimum L.). Among the all four environments, E1 had higher mean value for seed yield per plant and all other important yield contributing traits by sowing in second fortnight at Dahod conditions best for linseed cultivation. Combining ability analysis revealed importance of both additive and non-additive variances with prime role of non-additive genetic variance for seed yield per plant and its related traits in all environments as well as pooled over environments suggesting heterosis breeding would be more useful for development of superior hybrids if sterility system available. Among the parents; Shekhar, GS 384, KB 9610 and K 29 were good general combiners for seed yield per plant and test weight and capsules per plant. The parent viz., IPI 10, H 45, GS 384 and RLC 133 were good general combiners for earliness. The cross Indira × ILS 264, Gaurav × H 45 and RLC 133 × Shekhar showed higher sca effects for seed yield and test weight. Most of the crosses with high per se performance involved at least one good general combining parent such as Shekhar, GS 384, KB 9610 and K 29 through out for all studied characters.

Combining ability analysis for grain yield and quality characters in pearl millet [Cenchrus americanus (L.) Morrone

The objective of the present study is to estimate the combining ability effects among parents and their crosses in pearl millet, to identify promising cross combinations for grain yield and its component traits. In combining ability analysis, the extent of sca variance was higher than gca variance for all of the characters demonstrating the predominance of non-additive gene action except for panicle length and 1000-grain weight. The estimates of general combining ability suggested that parents, RIB 17 S/109, RIB 16300, RIB 37-40 S/17, RIB 13-16 S/17, ICMA 96666 and ICMA 94111 were good general combiners for yield and its contributing characters. The best hybrid, ICMA 94111 x RIB 16296 involved low x low performing parents which exhibited high positive and significant SCA effect for grain yield and most of the yield contributing and quality traits like protein, iron and zinc. These good combiner lines may be exploited to develop iron and zinc rich hybrids along with grain yield to alleviate malnutrition in people of the country. Keywords: Pearl millet, combining ability, gene action, male sterile line, tester.

Combining ability analysis in soybean through North Carolina mating design II under varying water levels and temperature at maturity stage

Combining ability analysis in soybean through North Carolina mating design II under varying water levels and temperature at maturity stage

Heterosis and Combining Ability Analysis in Maize Using Line X Tester Model

Twenty-two lines were crossed with 2 testers in a Line × Tester mating design in 2017-18 and the resulting 44 crosses along with the lines, testers and three checks i.e., BARI Hybrid Maize 9 (BHM 9), 981 and Elite were evaluated in a alpha lattice design with two replications, during rabi, 2018-19. Highly significant differences were found among the genotypes for all the characters studied. Parent and parents vs crosses were significant for all the characters except ASI indicating greater diversity in the parental lines of the traits. Three lines (viz., BMZ 55, BMZ 53, BMZ 4) showed significant negative GCA effect for both days to 50% tasseling and silking, indicating good general combiners for earliness. BMZ 15, BMZ 55, BMZ 53 and BMZ 68 showed significant negative GCA effects for both plant and ear height. BIL 79, Pinacle 17 and BIL 182 exhibited desirable significant positive GCA for grain yield. Considering desirable GCA effects those parents could be used extensively in hybrid breeding program to accumulate those favorable genes. However, two cross combinations BIL 182 x CML 429 and BIL 79 x CML 429 were found promising considering SCA effect, mean performance and could be utilized for enhancing hybrid production. Considering BHM 9 as check, the percent standard heterosis for grain yield varied from -52.6 to 0.6%. None of the crosses showed significant positive heterosis for grain yield except BIL 79 × CML 429.
 Bangladesh J. Agril. Res. 46(3): 261-274, September 2021

Combining Ability Analysis of Maize Inbred Lines Suitable For Machine Harvest

Using self selected maize inbred lines and hybrid combinations as test materials, the combining ability of maize hybrids suitable for machine harvest was analyzed. Ten maize inbred lines were selected as female parent (P1) and three inbred lines as male parent (P2). The experiment design of incomplete diallel cross was adopted in this study. The combining ability of 10 agronomic characters such as plant height, ear height, ear grain weight, ear length, ear diameter, number of rows per ear, number of grains per row, 100- grain weight, number of branches in male ear and water content at harvest were analyzed. The present findings revealed that in terms of general combining ability, JM39 was the best in ear length, grain number per row, 100-grain weight, branch number of male ear and water content at harvest, followed by JM35, JM26 and JM28. In terms of specific combining ability, the combination with better performance were JM39×JF167, JM39×JF200 and JM35×JF167. Moreover, JM26, JM28, JM35 and JM39 could be used directly, and the other inbred lines could be improved and reused. Plant height, number of rows per ear, number of grains per row and 100-grain weight should be selected in the early generation, while ear height, ear diameter, number of branches in male ear and water content at harvest should be selected in the late generation. Bangladesh J. Bot. 51(4): 889-895, 2022 (December) Special

Heterosis and Combining Ability Studies in A 5x5 Diallel Crosses of Maize Inbred Lines

The present study was conducted to evaluate the genetic architecture of five diverse maize genotypes using combining ability analyses. General combining ability (GCA) mean squares were non-significant for grain yield and its related components. Specific combining ability (SCA) mean squares were highly significant for grain yield, the number of grains per row and cob girth while non-significant for days to tasseling, days to silking, plant height, cob height and cob length. These studies suggested the preponderance of non-additive type of gene action for grain yield, cob girth and number of grains per row and additive gene action for days to tasseling, days to silking, plant height, cob height and cob length. The genotypes MIL2020-51 and MIL2020-52 were good general combiners for grain yield, grains per row, cob height and plant height. These lines were the poorest general combiner for days to 50% tasseling and days to 50% silking which suggested that these genotypes had sufficient genes for inducing earliness. The crosses MIL2020-51 x MIL2020-54, MIL2020-52 x MIL2020-53, MIL2020-51 x MIL2020-55, MIL2020-53 x MIL2020-55and MIL2020-52 x MIL2020-55 were the best performing combinations for grain yield. These crosses involved good x good and good x poor general combiners. The reciprocal cross combinations MIL2020-55 x MIL2020-53, MIL2020-52 x MIL20220-51, MIL2020-54I x MIL2020-52, MIL2020-55 x MIL2020-51, MIL2020-54 x MIL2020-51and MIL2020-55 x MIL2020-54 showed large positive estimates for grain yield suggesting that cytoplasmic inheritance also had a role in the expression of grain yield. SCA variances were higher than GCA variances for grain yield, plant height, cob height, number of grains per row, cob girth and cob length which highlighted major role of non-additive genes in the inheritance of these traits. Additive gene action was found more important for number of days to 50% tasseling and number of days to 50% silking

Selecting tropical wheat genotypes through combining ability analysis.

The selection of parents to originate promising base populations, as well as the knowledge of the gene effects controlling agronomic traits by means of diallel, are useful to drive genetic gains in Brazilian tropical wheat breeding programs. The goals of this study were to select tropical wheat parents with a high frequency of favorable alleles and segregating populations with high potential to originate superior progenies through partial diallel analysis. Thus, 14 parents were divided in two groups and crossed in a 7 × 7 partial diallel scheme to originate 49 F1 combinations. After obtaining F2 generation, the populations and the parents were evaluated in the field in the summer of 2021. Days for heading, plant height, rust and yellow spot resistance, and grain yield were evaluated. The data were subjected to partial diallel analysis. There were significant effects of general combining ability for all traits. The specific combining ability effect was significant for days for heading and plant height. The additive gene effects were predominant over the non-additive ones. The parents with the highest frequency of favorable alleles for the traits evaluated were selected in each group. Four populations with high genetic potential to originate superior progenies were selected.

Combining Ability Analysis for Yield and its Component Traits in Rice (Oryza sativa L.)

Combining Ability Analysis for Yield and its Component Traits in Rice (Oryza sativa L.)

Combining Ability Analysis for Yields and Its Components in Pearl Millet (Pennisetum glaucum L.)

Present investigation was carried out in Kharif 2022 to assess the magnitude than the general combining ability (GCA) effects for all the characters, indicating the preponderance of non-additive gene action for characters under study. The results indicate the presence of substantial variability in the selected materials for the study. The estimated components of variance for specific combining ability (SCA) effects were larger in magnitude than the general combining ability (GCA) effects for all the characters, indicating the preponderance of non-additive gene action for these characters. The estimates of GCA effects showed that the parents 418 R and 1358 R were good combiner for all the traits studied except number of grains/cm2 and fodder yield/ plant, respectively. The hybrids MS- 88004 A x 418 R and MS-863 A x 260 R were found superior with high SCA effects for seven important traits including grain yield as well as fodder yield per plant. Whereas, the crosses namely; MS-98222 A x 1358 R, MS-841 A x UCC-23 R, MS-841 A x 1404 R and MS-94555 A x 268 R registered higher SCA effects for the six important economic traits, including grain yield per plant. The crosses namely; MS-98222 A x 1358 R, MS-841 A x UCC-23 R, MS-841 A x 1404 R and MS-94555 A x 268 R registered higher SCA effects for six important economic traits, including grain yield per plant. These crosses were identified as superior and can be effectively utilized for hybrid breeding program.

Retracted: Combining Ability Analysis of Relevant Characters of Maize Inbred Lines Suitable for Machine Harvest

Retracted: Combining Ability Analysis of Relevant Characters of Maize Inbred Lines Suitable for Machine Harvest

Combining ability analysis for yield-attributing traits in cytoplasmic male sterility based hybrids of chilli (Capsicum annum)

Combining ability analysis for yield-attributing traits in cytoplasmic male sterility based hybrids of chilli (Capsicum annum)

Estimates of Combining Ability and Association among Morpho-Agronomic Traits of Single Cross Maize (Zea mays L.) Hybrids

Screening genotypes have a crucial role to increase the efficiency of selections in plant breeding program. Therefore, this study was emphasized to determine combining ability and the association between traits among themselves and yield. The experiment was conducted at Haramaya University Research Station (Raare) for two years (2018 and 2019) using 4x7 alpha-lattice design with three replications. Pooled analysis of variance revealed highly significant (p≤0.01) variations among crosses for grain yield and related traits. According to the result of combining ability analysis, parental line L3 was identified as a good general combiner for grain yield, ear diameter, 1000-kernel weight, and days to maturity. Similarly; L1, L2, and L8 proved as the best general combiner for number of kernels per row. Crosses L1×L6, L3×L5, L4×L6, L4×L8, and L5×L7 were found good specific combiners for 1000-kernel weight. Furthermore, the cross L5×L6 was the best specific combiner for ear diameter, whereas L4×L7 for both number of kernels per row and 1000-kernel weight. Likewise, the crosses L1×L5, L3×L8, L6×L7, and L7×L8 were identified as the best specific combiner towards earliness. Moreover, thousand kernel weight showed significant positive correlation with grain yield, conversely, days to anthesis, days to silking, ear aspect, and Puccinia sorghi exhibited significant negative correlation with grain yield at genotypic and phenotypic levels. Ear length, 1000-kernel weight, number of kernel rows per ear, and Turcicum leaf blight had positive direct effect on grain yield at genotypic and phenotypic level. In general, the result presented in the study might be useful for further breeding process to improve the productivity of maize.

DEVELOPMENT OF HIGH-YIELDING SESAME (SESAMUM INDICUM L.) GENOTYPES UNDER DROUGHT STRESS CONDITIONS

Ten drought-tolerant and six sensitive lines with their resultant crosses emerged from crossing in the Line × Tester mating design, then evaluated at the maturity stage in the field. Data recorded for morphological and physiological parameters took place, as well as, for drought tolerance and yieldrelated traits. Recorded data followed analysis to access the variability in germplasm and general and specific combining ability effects. Combining ability analysis exhibited variable direction and magnitude of specific combining ability effects among crosses and general combining effects among line and testers. Results showed the breeding material had genetic variability that can serve in developing drought-tolerant and high-yielding genotypes of Sesamum indicum L. The testers 93004 and 96019 and Lines 90005 and 96006 revealed the best general combiners under normal and drought stress. Results of SCA indicated that 95001 × 97005, 97007 × 97001, 95010 × 93004, TH-6 × 96019, and 90005 × 96014 exhibited to have positive significant specific combining ability effects for most of the traits under control and drought stress conditions that can undergo further evaluation for growing under drought conditions. The fresh and dry weight of seedlings and 1000-seed weight traits proved useful as selection criteria in developing drought-tolerant types in sesame.

Combining Ability and Heritability Analysis for Early Maturity and Yield Traits in Contemporary Spring Wheat (Triticum aestivum L.)

An experiment was carried out with North Carolina Mating Design II (NC II) derived F1 progenies along with parents to know nature of gene action in regulating early maturity, yield and yield contributing traits. The principal objective of this research was to identify best parents and specific cross combinations based on combining ability analysis and estimation of heritability. Hybrids and their parents were arranged in a 8 by 8 partially balanced lattice design with two replicates. Kanchan, BARI Gom-25 × BARI Gom-21, BARI Gom-26 × Kanchan, Rawal × Kanchan, Rawal × BARI Gom-22 and BARI Gom-23 × Kheri showed earliness and BARI Gom-25 × BARI Gom-21 showed highest yield potentiality. The genotypes BARI Gom-28 and BARI Gom-30 were used as checks and the selected genotypes performed comparatively better than the checks. The genetic analysis exhibited significant additive and non-additive genetic variations for all the traits. For earliness and yield potentiality the variance due to SCA was highly significant than GCA. Heritability estimates revealed low broad sense heritability except the traits i.e. days to 50% flowering, days to 100% flowering, plant height and 100-grain weight, which exhibited medium heritability. Narrow sense heritability was low for all the traits. The GCA effect of 15 parental genotypes was insignificant for all the traits that were assessed. BARI Gom-25 x BARI Gom-21, BARI Gom-23 x BARI Gom-21, BARI Gom-25 x BARI Gom-27, BARI Gom-26 x Kanchan, BARI Gom-26 x BARI Gom-28, BARI Gom-25 x BARI Gom-27 showed significant SCA effects for earliness. BARI Gom-25 x BARI Gom-22, BARI Gom-26 x CB51 showed significant SCA effects for yield potentiality.

ESTIMATION OF GENE ACTIONFOR THE SELECTION OF SUPERIOR PARENTS AND THEIR CROSS COMBINATIONSFOR YIELD AND FIBER ASSOCIATED ATTRIBUTES IN AMERICAN COTTON (GOSSYPIUM HIRSUTUM L.)

Cotton is very important crop regarding the global trade. It is grown for its fiber and edible oil in Pakistan. It contributes 1.5 percent to GDP and 69 percent in foreign exchange. There is need to enhance the yield per unit area of cotton by developing high yielding and stress tolerant varieties. In breeding program the parents and their crosses are selected on the basis of their combining ability. Combining ability analysis is performed to identify the general and specific combiner for yield attributed traits. This research was performed for evaluation of four lines as female parents (C-1, CIM-616, TIPO-1 and CYTO-608) and three testers as male parents (NIAB-1048, CYTO-124 and CIM-600) of cotton (Gossypium hirsutum L.). The traits such as plant height, first fruiting node, seed cotton yield, monopodial branches, sympodial branches, ginning out turn percentage, number of bolls per plant, height to node ratio and cotton seed yield was tested. The general combining ability of parental lines and specific combining ability of the F1 cross will be determined for yield related traits. The genotypes with good general combining ability and specific combining ability further exploited for hybrid/variety development programs. For most of the traits like number of monopods per plant, boll weight per plant, seed cotton yield, number of nodes per plant, 1st fruiting node, intermodal distance, ginning out turn percentage, cotton seed yield, seed index, plant height, fiber strength, fiber length, fiber uniformity and fiber fineness value had more value for dominance variance. The higher effects of GCA and SCA indicated that there is the role of additive and non-additive gene action for inheritance of traits.

Combining Ability Analysis for Fruit Yield in Bottle Gourd [Lagenaria siceraria (Mol.) Standl

Present investigation was carried out during Zaid season 2019-2020 in (Y1) and Zaid 2020-2021 in (Y2) at the Main Experimental Station (MES), Department of Vegetable Science, Acharya Narendra Deva University of Agriculture & Technology, Narendra Nagar, Kumarganj, Ayodhya (U.P) with 21 genotypes with six parental line and their fifteen F1 hybrids of bottle gourd by using diallel (excluding reciprocal) mating fashion. Experiment was laid out in RBD include three replication having each experimental unit with rows space at 3 (m) apart with a plant to plant spacing of 0.50 (m). Significant variances over seasons were found for general as well as sca for all the 17 traits studied during over season pooled which suggested that both additive and non-additive gene action were most important in the expression of all the traits. Pooled combining ability analysis revealed that parents viz., P4, P6 and P2 were good general combiner for fruit yield per plant. An attempt to identify desirable parents based on gca effect as well per se performance of the most of the character studied. Among the 15 F1 crosses P3 x P4, P2 x P6 and P2 x P5 have found good specific combiners for total fruit yield per plant along with most of the other yield contributing characters follow days to first staminate flower anthesis, days to first pistillate flower anthesis, fruit length and average fruit weight.

Persilangan Dialel Penuh pada Beberapa Genotipe Melon (Cucumis melo L.)

Melon productivity in Indonesia can be increased through the use of hybrid varieties. In order to obtain superior hybrids, information on general combining ability (GCA) and specific combining ability (SCA) is needed as a guide in selecting parents and combinations of superior crosses effectively and efficiently and to obtain the necessary information about the action of genes controlling plant traits. The aim of this study was to estimate the combining ability and gene action of melon crosses using full dialelic crosses. The research was conducted at the Greenhouse of Brawijaya University, Karangploso District, Malang Regency. The genetic material used was five melon parents {ACD211303 (1), ACD211254 (2), ACD221362 (3), ACD231380 (4), ACD231265 (5) which were planted and crossed in full dialelic to produce F1 hybrids. This research was conducted by planting 25 melon genotypes in a randomized block design, repeated three times. The results of the analysis of variance showed significant differences for several growth characters, namely leaf length (cm), leaf width (cm), stem diameter (mm), plant length (cm) and flowering age (DAP). The analysis of SCA variants on the characters of leaf length, stem diameter, plant length and flowering age was higher than that of the DGU variant which indicated that non-additive gene action dominated the inheritance of most of the characters. Combining ability analysis showed that the mean square of general combining ability (GCA) was significantly good for all characters. The combination of 1x3, 1x4, 1x5, 2x5 and 3x4 crosses is a superior cross combination and deserves further consideration as a candidate for hybrid varieties.

Combining Ability Analysis for Grain Yield and Some Agronomic Traits in Maize (Zea mays L.) Inbred Lines Throughout, Diallel Mating Design at Kassala State, Sudan

This study was conducted to analyze the combining ability for yield and some agronomic traits of maize inbred lines at two locations, Tacroof, Kassala Research Station farm and Sawagi in a farmer field, at Kassala state, Sudan Five parental line (TZBRD-ADQ-2, TZBRD-ADQ-3, TZBRD-ADQ-4, TZBRD-AD-5 and TZBRD-COMP-6) and their ten single cross (F1hybrid) (TZBRD-ADQ-2× TZBRD-ADQ-3, TZBRD-ADQ-2× TZBRD-ADQ-4, TZBRD-ADQ-2× TZBRD-AD-5, TZBRD-ADQ-2× TZBRD-COMP-6, TZBRD-ADQ-3× TZBRD-ADQ-4, TZBRD-ADQ-3 ×TZBRD-AD-5, TZBRD-ADQ-3× TZBRD-COMP-6, TZBRD-ADQ-4× TZBRD-AD-5, TZBRD-ADQ-4× TZBRD-COMP-6 and TZBRD-AD-5× TZBRD-COMP-6) of maize developed by using Diallel mating design. Four experiments were conducted in two consecutive summer seasons 2016 and 2017. The studied traits included days to 50% tasseling, days to 50% silking, plant height (cm), ear height (cm), ear length (cm), ear diameter (cm), number of rows per ear, number of kernel per row, 100 kernel weight (g), and grain yield (ton/ha). Out of the five parents considered as the best combiner at Kassala site, such as parent TZBRD-COMP-6, TZBRD-ADQ-3 and TZBRD-ADQ-4, which showed a highly significant general combining ability effects in desirable direction for all studied traits. Therefore, these lines could be utilized in improvement of the respective traits in any breeding programs where hybridization was involved. Regarding to, Sawagi location, the best combiner were the parents TZBRD-ADQ-3, TZBRD-COMP-6, and TZBRD-ADQ-2 recorded highly significant general combining ability effects in desirable direction for 50% tasseling, days to 50% silking, ear length, ear diameter, 100 kernels weight, number of row per ear, number of kernel per row and grain yield. Among the ten cross combinations, the best cross was, TZBRD-ADQ-2× TZBRD-ADQ-3 recorded significant SCA effect in the desirable direction for all traits except days to 50% silking, plant height and number of kernel per row at Kassala location, but at Sawagi location cross TZBRD-ADQ-3×TZBRD-COMP-6 recorded significant SCA effect in the desirable direction for days to 50% tasseling, days to 50% silking, plant height and number of kernel per row, followed by cross TZBRD-ADQ-2×TZBRD-ADQ-3 which recorded a significant SCA effect in the desirable direction for ear height, ear length and grain yield.

Genetical Contributions and Combining Ability Analysis in Bitter gourd (Momordica charantia L.)

The present study was undertaken to estimate the general and specific combining ability in 10 x 10 diallel set of crosses (excluding reciprocals) in bitter gourd to get 45 hybrids using 10 parents (DVBTG-1, VRBT-94, VRBT-39, VRBT-41, VRBT-49, VRBT-50, VRBT-103, VRBT-63, VRBT-32 and VRBT-6). These 45 F1 along with 10 parents were evaluated in Randomized Block Design with three replications considering 10 characters (days to first male flower anthesis, days to first female flower anthesis, days to first harvest, number of branches/plant, plant height, fruit length, fruit diameter, number of fruits/plant, fruit weight and fruit yield/plant) in bitter gourd. Analysis of variance due to treatment was highly significant for all the traits. The combining ability analysis revealed highly significant differences among the treatments for all the parameters studied. The variances due to sca were higher than the gca for all the characters indicating the predominance of non-additive gene effects. Out of 10 parents’ four parents DVBTG-1, VRBT-49, VRBT-103 and VRBT-32 exhibited significant and negative g.c.a effects for early female flowering and days to first harvest. Similarly, positive and significant g.c.a effects were shown by DVBTG-1, VRBT-50, VRBT-49, VRBT-103 and VRBT-6 for number of fruits/plant. DVBTG-1 and VRBT-49 showed negative gca effects for the characters except days to 1st harvesting. How VRBT-49 was identified as one of the best general combiners. The cross combinations VRBT-94 x VRBT-32, DVBTG-1 x VRBT-50, VRBT-49 x VRBT-103, VRBT-49 x VRBT-32, VRBT-94 x VRBT-32 and VRBT-41 x VRBT-103 exhibited positive and significant s.c.a effects for first female flower anthesis and days to first harvest. The finding of experiments confirmed the potentiality of DVBTG-1 x VRBT-6, VRBT-94 x VRBT-103, VRBT-41 x VRBT-6, VRBT-94 x VRBT-49, VRBT-39 x VRBT-49 and VRBT-94 x VRBT-39 combination based hybrids for yield/plant. The results of this study also suggest that for improvement of a desirable character, the selected parental line should be of high gca value and their F1s should express high specific combining ability. Significant estimates of additive component (d) along with significance of additive x additive (i) gene interaction-with positive sign pod yield per plant which indicated the presence of increase alleles and associated pair of genes.

Combining ability analysis in sunflower (Helianthus annuus L.)

A study was carried out to assess the combining ability of ten CMS lines with four testers using the line x tester method. Biometrical observations were taken for days to 50% flowering, plant height, head diameter, days to maturity, volume weight, hundred seed weight, seed yield /plant, oil content and oil yield/plant.  Specific combing ability variance was greater than the general combining ability variance for all the characters which indicated that non-additive gene action played a major role in inheritance.  The gca of parents were not in agreement with the per se performance for various traits.  Hence, the selection of parents should be based on gca alone for a breeding programme. Three lines viz., COSF 12A, COSF 13A and CMS 207A, and tester IR 6 were identified as good general combiners for seed and oil yield.  Among the hybrids generated using good general combiners, COSF 13A x IR 6 had the additive type of gene action for seed and oil yield per plant.  In general, most of the crosses had non-significant sca for oil yield per plant and oil content which indicated the presence of an additive type of gene action.  Hence, the selection of good general combiners for oil content, seed and oil yield will help to evolve high oil yielding hybrids in sunflowers. Keywords: Sunflower, line x tester, combining ability, seed yield, oil yield