Inheritance of Carbon Isotope Discrimination in Bread Wheat (Triticum Aestivum L.)

Summary Reliable selection of families with increased grain yield is difficult in breeding programs targeting water-limited environments. Carbon isotope discrimination (Δ) is negatively correlated with transpiration efficiency, and low Δ is being used for indirect selection of high wheat yield in rainfed environments. Yet little is known of genetic control and opportunities for improving selection efficiency of Δ in wheat. Half-diallel and generation means mating designs were undertaken to provide estimates of the size and nature of gene action for Δ in a range of wheat genotypes varying for this trait. Significant (P < 0.01) differences were observed for leaf tissue Δ among parents (19.3 to 20.7‰) and F₁ progeny (19.4 to 20.9‰) in the half-diallel. General (GCA) and specific combining ability (SCA) effects were significant (P < 0.05), while Baker's GCA/SCA variance ratio of 0.89 was close to unity, indicating largely additive gene effects. GCA effects varied from −0.38 to + 0.34‰ for low and high Δ genotypes `Quarrion' and `Gutha', respectively. GCA effects and parental means were strongly correlated (r = 0.95, P < 0.01) while directional dominance and epistasis contributed to small, non-additive gene action for Δ. Smaller Δ in F₁ progeny was associated with accumulation of recessive alleles from the low Δ parent. Narrow-sense heritability was high (0.86) on a single-plant basis. Generation means analysis was undertaken on crosses between low Δ genotype Quarrion and two higher Δ genotypes `Genaro M81' and `Hartog'. The F₁, F₂ and midparent means were not statistically (P > 0.05) different, whereas backcrossing significantly changed Δ toward the mean of the recurrent parent. Gene action was largely additive with evidence for additive × additive epistasis in one cross. Narrow-sense heritabilities were moderate in size (0.29 to 0.43) on a single-plant basis. Genetic gain for Δ in wheat should be readily achieved in selection among inbred or partially inbred families during the later stages of population development.     

Seedling emergence,coleoptile length,and plant height relationships in crosses of dwarf and standard-height wheats

Summary Seedling emergence was closely correlated with coleoptile length and plant height among parents, F₂ and F₃, populations of crosses involving dwarf wheats Olesen Dwarf (CI 14497), Norin 10 derivative D6301, Tom Thumb derivative D6899, and the standard-height varieties Ramona 50 and Nainari 60. Genetic mechanisms that governed plant height also influenced coleoptile length, but the relative effects of genes showing dominant or epistatic effects appeared to be different. With respect to the two parents involved in each of 15 crosses, mean F₂ coleoptile lengths were consistently closer to the low parent value than were corresponding mean F₂ plant heights. A slight curvilinear relationship was also found between coleoptile length and plant height of F₃ lines. The results suggest that selection of semidwarf wheats with long coleoptiles and improved emergence properties from crosses involving the dwarf wheats of this study would be unlikely.     

Analysis of diallel crosses between wheat genotypes with genetically different resistance to Pseudocercosporella herpotrichoides (Fron) Deighton

Two diallels were analysed for general combining ability (GCA) and specific combining ability (SCA) to study the resistance of crosses‐between wheat genotypes, advanced to the F₅ generation, to Pseudocer‐cosporella herpotrichoides. The parents either carried the resistance‐gene Pch‐1 or had different levels of quantitative resistance, one genotype was susceptible. At medium milk‐ripening, significant effects were‐found for GCA and SCA. GCA effects were the more important. Diallel crosses between genotypes, all carrying Pch‐1, revealed interactions‐of the gene with the genotypic background. Some combinations had a‐higher level of resistance than the best parent. In these populations'CH‐75417’ was involved as a parent. Both ‘CH‐75417’ and ‘F–210.13.4.42’ had significant GCA effects. Crosses between quantitatively resistant parents yielded populations that transgressed both parents. The increased resistance level was associated with ‘Cappelle‐Desprez’, distinguished by its high GCA. In some crosses SCA contributed significantly to an increase in resistance level. Selection for resistance within the best advanced populations is recommended since it‐takes advantage of additive gene action and the high heritability estimates based on ELISA values in plant progenies.     

Population genetics of self-incompatibility and developing self-compatible genotypes in niger (<Emphasis Type="Italic">Guizotia abyssinica</Emphasis>)

Two cucumber recombinant inbred lines (RILs) differing in plant habit were crossed and progeny self-pollinated to produce F₃ individuals upon which phenotypic selection was practiced to identify a base population which in turn underwent either two cycles of MAS or random mating without selection (RAN). MAS and RAN were practiced to produce F₄ and F₅ progeny sets. RIL, crossing parents, and F₃–F₅ progeny sets were then evaluated under replicated field conditions for fruit yield and quality (L:D and E:T) to evaluate gain from selection (ΔG). The broad-sense heritability (h ² B) over cycles (C) of selection ranged 0.22–0.45, 0.09–0.20, and 0.11–0.15 for yield, L:D, and E:T, respectively. Although one cycle of PHE selection followed by MAS was effective in conserving the performance of the traits examined during inbreeding, progeny performance during RAN fluctuated (F₄–F₅ generation; C₂). Lack of ΔG during advanced generations (F₄–F₅) of MAS was likely due to allelic fixation and/or optimized epistatic complementation.     

Estimates of additive and dominance effects for Fusarium head blight resistance of winter triticale

The most effective strategy to control Fusarium head blight (FHB), a devastating disease of small‐grain cereals, is breeding resistant cultivars. This resistance study of F₁ crosses, F₂ and backcross generations of triticale estimates heterosis, general and specific combining ability (GCA, SCA), additive and dominance effects and compares parents with segregating generations. The genetic material consisted of 10 parents with their 45 F₁ crosses and of six parents with their 15 F₂ progeny and backcrosses to each parent. Genotypes were grown in various environments and artificially inoculated with an aggressive isolate of F. culmorum. FHB was assessed, by visual rating, as the mean of four to five individual ratings of disease development. Heterosis for FHB was of little importance. The correlation between the FHB rating of F₁ crosses and their mid‐parent performance was close. GCA was the predominant source of variation, although the significance of the SCA variance also implied non‐additive allelic interaction. The preponderance of additive gene effects is encouraging for increasing resistance by a recurrent selection programme. The relationship between the GCA effect of a parent and its per se performance was close, which gives the possibility of predicting FHB resistance in F₁ crosses. Additive effects were predominant in the F₂ progeny and also in the backcrosses. Transgressive segregants could not be detected. Searching for them should be postponed to the F₃ or later generations.     

优异纤维品质陆地棉与转基因抗虫棉的配合力及遗传效应分析

 利用10个优异纤维品质陆地棉品种和6个转Bt基因抗虫棉品种配组的10×6 NCII交配设计,对其产量、品质及抗虫性的配合力及遗传效应进行了分析。结果表明：Bt基因能在F₁得到显性遗传。以A₈的产量性状一般配合力最高,A₄的纤维品质性状一般配合力最高;A₇×B₅、A₆×B₁等组合的各性状特殊配合力较好;亲本的一般配合力与组合间特殊配合力不存在显著相关性。遗传效应分析表明,基因加性效应对铃重、衣分、2.5%跨长、比强度、伸长率等性状起主导作用;双亲的互作效应对F1产量性状起重要作用;2.5%跨长、铃重、比强度的狭义遗传力较高,产量性状的狭义遗传力最低。     

Combining ability of soybean (Glycine max) for low phosphorus tolerance on acidic soils of Western Ethiopia

Determining the gene actions governing the inheritance of traits of interest has paramount importance in designing a breeding approach to improve the progeny populations. This study was undertaken to determine the combining ability of nine selected parental lines in the F₂/F₃ segregating populations for low P tolerance. The experiment was laid out in an alpha lattice design in two locations, that is Mettu and Assossa of Western Ethiopia that are characterized by soils with low P and pH. General combining ability (GCA) effects were highly significant for grain yield, pod length, days to maturity and plant height, while specific combining ability (SCA) effects were highly significant for grain yield, 100-seed weight, pod length and plant height. The parent Hardee-1 was identified as the best general combiner for yield, number of seeds per pod, pod length, plant height and pod number. The results suggest that additive gene action was important for several of the studied traits, implied by significant GCA effect, which might indicate selection for these traits could be effective in later segregating generations.     

Combining ability analysis for harvest index in winter wheat

Summary Cereal breeders have used harvest index (HI) as a selection criterion in segregating generations to identify physiologically superior lines with improved partitioning of total assimilate into grain. Information on combining ability for HI of the hard red winter wheat (Triticum aestivum L.) cultivars of the Southern Great Plains is not available. A study was undertaken to examine HI of seven genetically diverse winter wheat parents, evaluate their general combining ability (GCA) and specific combining ability (SCA) effects, and study correlations of HI with several agronomic traits. The seven parents were crossed in a half-diallel mating design to produce 21 crosses. The F₁'s, their F₂ progenies, and the parents were evaluated in replicated field tests at Stillwater and at Lahoma, OK. The combining ability analysis was performed using Griffing's Method 4, Model 1. The results showed significant variation among parents for HI. The GCA and the SCA effects were mostly inconsistent between generations and between environments. However, parents with consistently high HI and positive GCA estimates were identified. The progeny with high HI mostly resulted from parents with high GCA estimates. The correlations between HI and agronomic traits indicated that improvement in HI should also result in high grain yield, early maturity, and short plant height.     

Identification of superior parents and hybrids for improving canola production under optimum and late sowing conditions

Major advancement in canola breeding depends on heterotic hybrids that require high general combining ability (GCA) and specific combining ability (SCA) inbred lines. In order to estimate heritability, gene action type, GCA, SCA and heterosis and to identify superior hybrids with wider adaptation to cold, one hundred canola hybrids were produced by crossing 10 lines and 10 testers in a Line?×?Tester mating design. The F₁ and F₂ generations were sown in α-lattice design in 2012 and 2013 growing seasons under optimum (early October) and late sowing (early November) conditions to be evaluated for days to flowering, days to physiological maturity, number of pods per plant, number of seeds per pod, thousand seed weight, seed yield and leaf electrical conductivity. The combined analysis indicated sufficient genetic diversity in the population and significant difference between two sowing date. The Line?×?Tester analysis presented significant GCA and SCA effects for all studied traits across optimum and late sowing conditions. The main gene action type was found to be non-additive, especially incomplete dominance and over-dominance in both conditions. Narrow-sense heritability ranged from low to moderate whereas broad-sense heritability was recorded more than 60% for all of the studied traits in both generations and conditions. The average heterosis in F₂ population for all studied traits was lower than that in F₁ representing this fact that heterosis is generally related to the heterozygosity at the population level and poorly correlated with heterozygosity at the individual level.     

Genetic analysis of mechanisms associated with inheritance of resistance to sheath rot of rice

Understanding genetic mechanisms controlling inheritance of disease resistance traits is essential in breeding investigations targeting development of resistant genotypes. Using North Carolina design II, 32 F₁ hybrids were generated by crossing eight susceptible to four resistant parents and submitted for field evaluation. The analysis of general and specific combining ability (GCA and SCA) indicated involvement of additive and non‐additive gene action controlling inheritance of horizontal resistance to sheath rot of rice. High GCA/SCA ratio and high heritability estimates revealed additive effects and were more predominant than none additive ones. The level of dominance indicated dominant genes was more important than recessive genes. Estimates of GCA and SCA analysis suggested that crop improvement programmes should be directed towards selection of superior parents or good combiners, emphasizing on GCA. As far as source of resistance is concerned, most promising genotypes were Cyicaro, Yunertian and Yunkeng. The predominance of additive genetic effects together with the relevance of dominant genes suggested possibilities of improving the resistance by introgression of resistance genes through recurrent selection coupled with phenotypic selection.     

Diallel analysis of sooty stripe resistance in sorghum

Sooty stripe [Ramulispora sorghi (Ellis and Everhart) Olive and Lefebre] is a widespread foliar disease of sorghum [Sorghum bicolor (L.) Moench] in West Africa, responsible for grain yield losses up to 46%. We studied the inheritance of sooty stripe resistance in a 9 × 9 sorghum F₂-population diallel grown together with parent lines and checks in1996 under natural disease pressure at two locations in Mali. The percentage of infected leaf area was determined twice over a two-week interval during the season. At the second evaluation, the mean sooty stripe severity amounted to 13% infected leaf area at Samanko and 12% at Cinzana. The frequency distribution of the entries was approximately normal for the mean disease severity, averaged across assessment dates and locations, pointing to the involvement of multiple genes. With the data combined across the two locations, genetic differences among lines and among F₂ populations were highly significant. Genotype × location interaction variances were also significant but much smaller than the genetic variances. Broad-sense heritability estimates were 0.92 for lines and 0.94 for the F₂ populations, for the mean percentage infected leaf area across the two assessment dates. General combining ability effects (GCA) determined most of the differences among the F₂ populations. Specific combining ability effects (SCA), and the interactions of GCA or SCA with locations were also significant but less important. Line performance per se was highly correlated with GCA. Because of the high heritability and predominance of additive effects, prospects are good for the genetic improvement of resistance to sooty stripe in sorghum in Mali, using simple pedigree or recurrent selection procedures. This revised version was published online in August 2006 with corrections to the Cover Date.     

Genetic effects determining rice grain weight and grain density

Summary Increasing grain weight is one means of increasing rice (Oryza sativa L.) grain yields. Selection for increased density of filled grains may offer an approach to increasing rice grain weight. Before rice breeding programs can begin effectively selecting for higher grain density, the nature and amount of the genetic variation present must be evaluated. A Design II mating plant with two sets was constructed using 16 parents. The 16 parents were representative of cultivars and elite breeding material available to breeders of long-grain rice in the southern U.S. The parents and 32 F₁ hybrids were evaluated in 1990 at two Arkansas locations: Stuttgart and Marianna. Additive variation was essentially zero for grain density as indicated by nonsignificant general combining ability (GCA) and specific combining ability (SCA) mean squares and a narrowsense heritability estimate –0.04 (±0.07). Increasing rice grain weight through increased grain density would not be feasible in U.S. southern long-grain rice unless new germplasm with higher filled grain densities is introduced. Genetic variation for grain weight was predominately additive and complemented with additive x additive epistatic variation, indicating that selection for increased grain weight could be practiced in segregating generations. The small proportion of epistatic variation to additive variation would not justify delaying selection until epistatic combinations are fixed in the homozygous line. Midparent grain weight means would serve as an adequate indicator of progeny performance for cross appraisal.Abbreviations GCA General Combining Ability - SCA Specific Combining Ability     

Inheritance of beta-carotene-associated mesocarp color and fruit maturity of melon (<Emphasis Type="Italic">Cucumis melo</Emphasis> L.)

Melon (Cucumis melo L.) fruit production in U.S. can be improved through the introgression of early fruit maturity (FM) and the enhancement of fruit color [i.e., quantity of β-carotene (QβC); orange mesocarp]. However, the genetics of FM and QβC have not been clearly defined in U.S. Western Shipping market class melons (USWS). Thus, a cross was made between the monoecious, early FM Chinese line ‘Q 3-2-2’ (non-carotene accumulating, white mesocarp) and the andromonecious, comparatively late FM USWS line ‘Top Mark’ (carotene accumulating; orange mesocarp) to determine the inheritance of FM and QβC in melon. Parents and derived cross-progenies (F₁, F₂, F₃, BC₁P₁, and BC₁P₂) were evaluated for FM and QβC at Hancock, Wisconsin over 2 years. Estimates of narrow-sense heritability (h _N²) for QβC and FM as defined by F₁, F₂, and BC (by individuals) were 0.55 and 0.62, respectively, while estimates based on F₃ families were 0.68 and 0.57, respectively for these traits. Mesocarp color segregation (F₂ and BC₁P₂) fit a two gene recessive epistatic model, which in turn, interacts with other minor genes. Although the inheritance of QβC and FM is complex, introgression (e.g., by backcrossing) of early FM genes resident in Chinese germplasm into USWS market types is possible. Such introgression may lead to increased yield potential in USWS market types while retaining relatively high β-carotene fruit content (i.e., orange mesocarp), if stringent, multiple location and early generation family selection (F_3–4) is practiced for FM with concomitant selection for QβC.     

Heterosis,combining ability and genetic effect,and relationship with genetic distance based on a diallel of hybrids from five diverse <Emphasis Type="Italic">Gossypium barbadense</Emphasis> cotton genotypes

The cultivated tetraploid Gossypium barbadense L. cotton produces superior natural fibers for the textile industry in the world. However, the possibility in utilization of heterosis to further increase its lint yield has not been extensively explored. In this study, two commercial US Pima cotton cultivars and three exotic G. barbadense lines, together with all of their possible hybrids in F₁ and F₂ progeny without reciprocals, were tested for lint yield, yield components, and fiber quality traits in four environments in 2005–2007. With a few exceptions, genotype (G), environment (E), and G × E were all significant or highly significant for all the traits studied. General combining ability (GCA) variances for all the traits in both F₁ and F₂ were also significant, while specific combining ability (SCA) variances were detected only for lint yield, fiber length, and micronaire in both generations and boll weight in F₁. GCA × E was also detected for lint percent, seed index, and fiber length in both F₁ and F₂, and boll weight in F₁, but none of the traits had significant SCA × E. As a group, F₁ and F₂ out-yielded the parent group by 20–40% and 6–10%, respectively. Mid-parent heterosis (MPH) for lint yield in F₁ was generally positive, ranging from ?4.7 to 116.4% with an average of 21.2–48.7%, while lint yield MPH in F₂ ranged from ?23.3 to 69.4% with an average of 6.4–12.4%. However, useful heterosis in lint yield was only detected in the hybrid between the two US commercial cultivars Pima S-7 and DP 340. MPH for other traits was low or not detected. MPH in F₂ was lower than that in F₁ but they were generally positively correlated. The genetic distances (GD) of the parents (based on 467 polymorphic RAPD and AFLP markers) between the five parents was not consistently correlated with MPH and SCA of their hybrids and dominant effects for lint yield and other traits. However, significant and positive correlations between GD of parents and the performance of their hybrids were detected for lint yield, lint percentage, and lint index in both F₁ and F₂ in most of the tests. GD of parents was also correlated with their GCA and additive effects in lint yield, lint percent, lint index, micronaire, plant height, and elongation. The results suggest that the close correlation between GD and hybrid performance per se was mainly due to the existence of GCA and additive effects from parents.     

Breeding long coleoptile, reduced height wheats

Semidwarf wheats have the potential to produce high yields when sown and managed under optimal conditions. However, farm yields often fall below this potential because of poor seedling establishment and low early vigour associated with gibberellic acid (GA)-insensitive reducing-height ( Rht) genes contained in these wheats. Australian and overseas wheats containing major and minor Rht genes sensitive to GA were intercrossed to develop three populations. Seedlings sensitive to GA and therefore lacking Rht-B1b ( Rht1) and Rht-D1b ( Rht2) plant height genes were selected for further study. GA- sensitive F4-derived lines were sown in field and glasshouse environments to determine plant height, and then sown at four temperatures to determine coleoptile length. Genetic variation in plant height and coleoptile length was large and significant ( P<0.01) among lines within each population with a number of lines identified as producing plant heights as short as current semidwarf varieties. Transgressive segregation for coleoptile length produced progenies with coleoptiles significantly ( P < 0.05) longer than the longest coleoptile parent in each population. Genotype × temperature interactions for coleoptile length were small thereby resulting in high line-mean heritabilities (h2 = 85–89) for this character. Larger plant-to-plant variation reduced single-plant estimates of heritability for plant height (h2 = 29–31) but heritability was increased (h2 = 68–78) with replication within and over environments. High narrow-sense heritabilities indicate that phenotypic selection should produce modest genetic gain for both characters. Variation in coleoptile length was poorly related to differences in plant height (r2 = 0.00 to 0.04 ns) while selection differentials for plant height were not associated with any change in coleoptile length of the selected groups. When considered together, height and coleoptile length appeared to be largely under independent genetic control among GA-sensitive wheats. These results suggest that GA-sensitive Rht genes could be used to select shorter height, longer-coleoptile wheats with improved establishment and seedling vigour. This revised version was published online in July 2006 with corrections to the Cover Date.     

Means and variances for Fusarium head blight resistance of F2-derived bulks from winter triticale and winter wheat crosses

Fusarium head blight (FHB), caused by Fusarium graminearum and Fusarium culmorum, is a devastating disease in cereals. This study was undertaken to estimate progeny means and variances in each of five winter triticale and winter wheat crosses using unselected F₂−derived lines in F₄ or F₅ generation bulked at harvest of the previous generation. Fifty (triticale) and 95 (wheat) progeny per cross were inoculated in two (triticale) or three (wheat) field environments. FHB rating was assessed on a whole-plot basis. Mean disease severities of the parents ranged from 2.3 to 6.4 in triticale and from 3.1 to 6.5 in wheat on a 1-to-9 scale (1 = symptomless, 9 = 100% infected). The midparent values generally resembled the means of their derived progeny. Significant (P < 0.01) genotypic variance was detected within each cross, but genotype × environment interaction and error variances were also high for both crops. Medium to high entry-mean heritabilities (0.6–0.8) underline the feasibility of selecting F₂-derived bulks on a plot basis in several environments. Phenotypic correlation of FHB resistance between generation F_2:4 and F_2:5 was r = 0.87 (P < 0.01) tested across 150 wheat bulks at two locations. Our estimates of selection gain are encouraging for breeders to improve FHB resistance in triticale and wheat by recurrent selection within adapted materials.     

Correlated selection responses of fiber properties measured by high volume instrument and advanced fiber information system in Upland cotton

Fiber properties measured by high volume instrument (HVI) and advanced fiber information system (AFIS) are currently being used in Upland cotton (Gossypium hirsutum L.) breeding. It would be interesting to know if it is equally efficient in selection for parameters measured by the two instrumental systems and how are the correlated selection responses of the parameters between the two systems. A study was designed to determine the correlated selection responses between fiber properties measured by the two systems in F₃, F₄, and F₅ generations of two crosses, FM 832 × SP 205 and MD 52ne × JJ 1145ne. Selections for HVI-fiber length, HVI-short fiber content, and HVI-maturity were made in the F₃ generation and the correlated responses of AFIS-fiber properties to the selections were estimated in the subsequent F₄ and F₅ generations. Selections for AFIS-fiber length, AFIS-short fiber content, and AFIS-maturity were made in the F₄ generation and the correlated responses of HVI-fiber properties to the selections were estimated in the F₅ generation. Moderate to high realized heritability was identified for both HVI- and AFIS-fiber properties. Significant correlated selection responses of fiber length and maturity between the HVI and AFIS methods were consistently observed in both crosses, suggesting similar genetic basis for fiber length and maturity measured by HVI and AFIS. Therefore, equal effectiveness is expected of the selection for both traits by the two instrumental systems. Correlated selection responses of short fiber content parameters between the HVI and AFIS methods were not consistent, suggesting a possible different genetic basis or differential variations of measurement quality between the two systems.     

Combining ability analysis of resistance to Helminthosporium leaf blight in spring wheat

Wheat breeders in South Asia are attempting to develop wheat (Triticum aestivum L.) cultivars resistant to Helminthosporium leaf blight (HLB), which occurs mainly as a complex of spot blotch caused by Cochliobolus sativus (Ito & Kuribayashi) Drechs. ex Dastur, and tan spot caused by Pyrenophora tritici-repentis (Died.) Drechs. Information on the combining ability for HLB resistance in wheat cultivars of South Asia is not available. This study was undertaken to examine the resistance to HLB in nine genetically diverse wheat parents, and to evaluate their general combining ability (GCA) and specific combining ability (SCA) effects toward determining the genetic basis of disease resistance. Nine parents were crossed in a half-diallel mating design to produce 36 populations. The F₁ and F₂ progenies, and the parents were evaluated in replicated field tests at Rampur, Nepal. Multiple disease scores were recorded, and area under the disease progress curve (AUDPC) was calculated to measure disease severity over time. The combining ability analysis was performed using Griffing's Method 2, Model 1. The parents chosen showed wide variation for resistance to HLB. They and the F₁ and F₂ progenies differed significantly for AUDPC. GCA and SCA effects were significant in both generations suggesting that additive as well as non-additive genetic mechanisms were involved in the expression of resistance in these parents. Wheat genotypes 'SW89-5422', 'G 162', 'NL 781'and 'Chirya 7' had significantly negative GCA effects for AUDPC in both F₁ and F₂ generations, suggesting their prime suitability for use in wheat breeding programs to improve resistance to HLB. The estimate of narrow-sense heritability was 0.77 in both generations suggesting that selection for HLB resistance should be effective in these crosses. The results indicate a predominance of additive gene action in the inheritance of HLB resistance in spring wheat.     

Inheritance of resistance to Fusarium wilt and yield traits in pigeonpea

Fusarium wilt is the main pigeonpea production constraint in Malawi. The purpose of the study was to understand the nature and mechanism of inheritance of F. wilt resistance, yield and secondary traits in pigeonpea. 48 crosses were generated in a 12 lines × 4 testers mating scheme. Some F₁ plants were selfed for segregation analysis for inheritance pattern of resistance, while others were evaluated for resistance, yield and secondary traits. There were significant variations among F₁ plants for F. wilt, days to 50 % flowering, seed/pod, and number of secondary branches. Specific combining ability (SCA) effects were predominant for F. wilt, days to 50 % flowering and number of secondary branches. The general combining ability (GCA) effects, mainly due to maternal genotypes, were preponderant for yield and other secondary traits. The significance of GCA and SCA effects suggested that variations were due to additive gene action in both the testers and parental lines arising from their interactions, and the dominance effects due to interactions of the parental lines. The χ² analysis suggested dominant patterns of inheritance for wilt in most of the F₂ populations. The segregation ratios of 3:1, 15:1, and 9:7 suggested the involvement of single or two independent/complementary dominant genes in the test donors. Involvement of a few genes governing wilt resistance suggested the ease of breeding for this trait. Pedigree breeding method would be recommended for incorporating various traits in pigeonpea.