جستجوی مقالات مرتبط با کلیدواژه « تجزیه دای آلل » در نشریات گروه « زراعت »

Wheat is attacked by many pathogens during the growing season, including rust. The causative agent of fungal wheat brown rust called Puccinia recondita f. sp. is also known as leaf rust. The most important way to control brown rust disease is to use resistant cultivars that effectively control and reduce its damage. The most important way to control brown rust disease is to use resistant cultivars that effectively control and reduce its damage. The aim of this study was to investigate the inheritance of brown rust resistance in different wheat cultivars and estimation of genetic parameters using diallel crossing.

Six bread wheat cultivars including Gonbad, Shiroudi, Darya, Atrak and Moghan 3 genotypes with susceptible Bolani cultivar and 15 F1 progenies from one-way diallel crosses were studied. his study was conducted as a randomized complete block design with three replications in field and greenhouse conditions. Traits included infection type, severity of infection, area under disease progression curve and incubation period. Data analysis was performed using SAS ver 9.1 and Excel software and estimation of genetic parameters and heritability of traits were studied by diallel analysis using Griffing's second method with fixed model and Jinks and Hayman method.

Analysis of variance showed that there was a significant difference among genotypes for all traits, indicating genetic variation for these traits and thus genetic analysis could be performed. The mean squares of general and private combining ability were significant for all traits, indicating the importance of both enhancing effects and dominance of genes in inheriting these traits. The Baker ratio indicated the same importance of additive effects and dominance for the incubation period and for the other traits indicated greater importance of additive effects. Estimation of genetic parameters by Jinks and Hayman method showed that for all four traits, the amount of D component was lower than the dominance components (H1 and H2), indicating that the dominance component was more important than the additive component in controlling these traits. The sign of F was positive for all traits, so the frequency of dominant alleles was higher than that of recessive alleles. Wr-vr statistic was significant for all studied traits, indicating the presence of inorganic effects (epistasis). In other words, the significance of this statistic indicates the inaccuracy of the additive-dominance model for traits.

Based on the traits evaluated in field, Atrak cultivar and in greenhouse, Gonbad cultivar had good resistance to brown rust. Narrow-sense heritability of traits was estimated to be between 51 and 86%. Estimation of genetic parameters showed that additive-dominance model was not sufficient. In other words, at least resistance is predictable in resistant cultivars.

In this research, the genetic analysis of some of the important agronomic traits in a number of barley cultivars was investigated under favorable irrigation (non-stress) and drought stress conditionsusing Griffing’s secondmethod and GGE-biplot. The plant materials consisted of seven barley cultivars (Valfajr, Makuei, Kavir, Reyhan, Gorgan-4, Nosrat and Nimrouz) and 21 hybrids derived from their half diallel crosses that were evaluated using a randomized complete block design with three replications under two favorable irrigation and drought stress conditions in 2015-2016. Genotypic mean squares for all studied traits except for harvest index and plant height undernormal irrigation conditions and harvest index, plant height and awn length under drought stress conditions were significant. Specific combining ability (SCA) was also significant for all traits except for stem diameter and seed length under normal conditions and biological yield, spike length, 100-grain weight and peduncle length under drought stress conditions. GGE biplot graph for grain yield explained 83.1% and 86.5% of total varianceunder favorableirrigation and drought stress conditions, respectively. Evaluating the general combining ability (GCA) of the studied lines under both favorable irrigation and drought stress conditions showed that Nusrat, Valfajr, Kavir, Nimrouz, Makuei, Reyhan and Gorgan-4 lines had the higher GCA, respectively. Assessing the SCA also showed that Nosrat, Reyhan and Gorgan-4 lines under favorable irrigation conditions and Nosrat and Valfajr lines underdrought stress conditions had the higher SCA than the other lines.Also, Valfajr × Nosrat and Kavir × Nosrat hybrids under favorable irrigation conditions and Valfajr × Nimrouz and Kavir × Nosrat hybrids under drought stress conditionswere the best hybrids in this research.

Six rainfed durum wheat genotypes (Chehel daneh, Gerdish, Zardak, Syrian-1, Waha and Knd1149//68/ward) and their complete diallel progenies of F1 generation were evaluted in a randomized complete block design with two replications. Analysis of variance indicated genetic differences among genotypes. General combining ability (GCA) was significant for all of the studied traits except hundred grain weight (HGW). Specific combining ability (SCA), reciprocal and non-maternal effects were significant for grain yield (GY), HGW and flag leaf area (FLA). The results indicated low values of narrowsense heritability and superiority of dominance effect for plant height (PH), GS, GY, HKW and FLA. The cross of Waha × Knd1149//68/ward with high value of GY and GCA for this trait can be used as a suitable cross for use of heterosis. This cross was also superior to their parents according HGW, NGS and SL. Gerdish can be used as a suitable parent for breeding programs to receive lines with high yield and yield components according to positive and significant GCA for number of spikelets per spike, SL, NGS, GY and FLA. According to predominance of additive effects in genetic control of number of spikelets per spike and spike length, selection can be useful for improvement of these traits, while selection was not applicable in primary generations and should be delayed for the other traits untill advanced generations.

Five wheat varieties were used to estimate gene action for morphological traits and yield and estimate the heritability of traits. The varieties including White Bolani, Brown Bolani, Tajan, Kealk and AS48 mutant have been crossed based on full diallel. The F2 genotypes were planted in a randomized complete block design with three replications in the Nuclear Agricultural Research Institute. Analysis of variance for all the traits revealed that the general combining ability was significant so these traits were controlled by additive genetic effects. The heritability of traits were high and therefore selection based on these will be successful. Additive-dominance model was sufficient for this research and non-allelic effect weren’t observed, therefore Hayman analysis was performed. Hayman’s analysis of variance showed that the additive effects and non-additive effects control the traits. For number of spikelet per spike, second and third internodes diameter, second and third internodes length and leaf area traits, the average degree of dominance indicate that partial dominance controls these traits. Heyman’s graphical analysis showed that partial dominance was involved in controlling these traits.

To estimate the gene action and heritability of traits related to cooking quality in rice varieties، F2 generations derived from diallel crosses of six rice varieties including Hassani، Shahpasand، Kadous، Vandana، Hashemi and IR36، together with their parents were assessed in a randomized complete block design with three replications in research field of Faculty of Agricultural Sciences، University of Guilan، in 2012. Result of diallel analysis based on the second method of Gardner and Eberhart showed that variety and heterosis effects were significant at 1% probability level for all studied traits indicating additive and dominance variances، respectively. Average heterosis was significant for gelatinization temperature showing significant differences between average parents and hybrids، but was not significant for amylase content and gel consistency. In contrast، specific heterosis was significant for all studied traits. Result of diallel analysis on the basis of third method of Gardner and Eberhart demonstrated that differences among parents and among crosses were significant for all measured traits indicating general and specific combining ability for varieties، while the effect of parents versus crosses (heterosis effect) was not significant for amylase content and gel consistency that confirmed the results of the second method of Gardner and Eberhart. Estimation of Baker ratio showed the higher non-additive than additive effects for amylase content، approximately equal proportion of the additive and non-additive effects for gel consistency and the higher additive than non-additive effects for gelatinization temperature. The graphical analysis of Hayman method showed that all measured traits were affected by partial dominance effects and relatively high narrow-sense heritability indicated higher proportion of additive gene effects for controlling the studied traits. Totally، the results of this research showed that to improve grain cooking quality in the studied population، can firstly be used the additive gene effects via selecting the higher quality genotypes and then the dominance gene effects is utilized by hybridization of the superior genotypes. Furthermore، IR36، Kadous and Shahpasand varieties and Hashemi×Shahpasand، Kadous×Hassani، Hassani×Shahpasand and Kadous×IR36 Crosses had the suitable values for grain cooking quality related traits and are recommended to improve these traits.

Seven rice varieties (Hassani, Deilmani, Sepidrod, Shahpasand, Saleh, Neda, and IRFAON215) along with their complete diallel progenies were grown in a randomized complete block design of three replications in the growing seasons of 2006 and 2007 and were evaluated for the quantitative traits of: number of days to flowering, flag leaf length, width and area, plant height, panicle length, extrusion length of panicle from sheath as well as grain yield. Analysis of variance indicated genetic differences among genotypes. General Combining Ability (GCA), Specific Combining Ability (SCA), reciprocal and non-maternal effects were significant for all the traits. Among genotype × year interactions, GCA×year were significant for flag leaf width, plant height, panicle length, extrusion length of panicle from sheath as well as for grain yield while SCA×year were significant for number of days to flowering, flag leaf width and area, panicle length, extrusion length of panicle from sheath and as well for grain yield. Dominance effect was predominant for flag leaf width and area and for panicle length, whereas additive effects were more prominent than the dominant ones for days to flowering, flag leaf length, plant height, extrusion length of panicle from sheath and as well for grain yield per plant. Therefore, selection for these traits can be useful in rice breeding programs.

Five rice genotypes (Hasseni, Dailamani, Shastak-mohammadi, Sange-tarom andDaei-shastak) and their 10 hybrids obtained through half diallel set were evaluated forcombining ability and gene effect studies of grain density trait. Single seedlings of eachentries were transplanted at 20×20 cm spacing in 3×5 m2 plots in a randomized blockdesign replicated three times during 2004-2005 at research station of Agricultural Sciencesand Natural Resources University General combining ability (GCA) and specific combiningability (SCA) was analyzed for this agronomic trait. The results showed significantdifference between general (GCA) and specific combining ability (SCA) for theinvestigated character. This indicates the role of additive and non-additive gene actionin inheritance of the trait. Also the results showed that selection for grain densitycharacter can’t well succeed, because of there was a high amount of non-additive geneaction in the genetic variance. Thus this character was important for production ofhybrid variety and application of heterosis. In this study, investigation of graphic Wr-Vranalysis for grain density indicated overdominance effect because the regression lineintercepted the Wr axis at negative point (a = -118/024). Also, the GCA effects of eachparent for this trait showed that the Daei-shastak is good general combiner for graindensity.

Five rice genotypes (Hassani, Dailamani, Shastak-mohammadi, Sange-tarom andDaei-shastak) and their 10 hybrids obtained through half a diallel set were evaluated forcombining ability and gene effects studies of early maturity and yield traits. Singleseedlings of each entries were transplanted at 20×20 cm spacing in 2×4 m2 plots using arandomized block design with three replications during 2004-2005 at research station ofSari Agricultural Sciences and Natural Resources University. General combining ability(GCA) and specific combining ability (SCA) were calculated for these agronomic traits.The results showed significant difference between general (GCA) and specificcombining ability (SCA) for the investigated characters. This indicates the role ofadditive and non-additive gene effects in inheritance of the traits. Also the resultsshowed that selection for early maturity and yield characters can’t well succeed,because of there were a high amount of non-additive gene effects in the geneticvariance. Thus, these characters were important for production of hybrid variety andapplication of heterosis. In this study, investigation of graphic Wr-Vr analysis for earlymaturity indicated overdominance effect because the regression line intercepted the Wraxis at negative point (a = -6.64). The GCA effects of each parent for these traitsshowed that the Daei-shastak is good general combiner for yield.

Six advanced durum wheat lines with different levels of resistance to Russian wheat aphid (RWA) were crossed in half-diallel method. Seedlings of F1 and their parents were grown in greenhouse and artificially infected with RWA. Analysis of variance and diallel analysis using Griffing, and Jinks and Hayman methods were performed for leaf rolling and chlorosis (percentage of leaf rolling and chlorosis) traits. General and specific combining abilities for resistance to Russian Wheat Aphid were significant for both traits indicating the role of additive and non-additive gene effects in controlling these traits. Jinks and Hayman analysis revealed higher additive gene effect as compared to non-additive gene effects. Non-additive gene effects were of partial dominance type for both traits. Less leaf rolling and chlorosis (greater resistance) were under control of recessive and dominant alleles, respectively. Broad and narrow sense heritability for resistance to RWA based on leaf chlorosis damage were 58 and 45 percent and for leaf rolling were 86 and 62 percent, respectively implying potential for improving resistance to RWA based on leaf rolling as compared to leaf chlorosis trait.

In order to study the genetic control of different traits in maize, a diallel mating was used with 14 inbred lines. Parents and their F1 generations were evaluated in a RCB design with three replications at research farm of Seed and Plant Improvement Institute in Karaj in 2006. Hayman and Jinks method was used for data analysis. The results indicated over dominance genes effect for plant height, ear height, number of kernel per row, number of kernel per ear, 100-seed weight, and kernel moisture percent and for yield Gene effects for ear length, ear diameter, number of row per ear, corn cob percent and kernel weight per ear were partial dominance. The increasing alleles for 100-seed weight, corn cob percent and kernel moisture percent were ressecive and for other traits were dominant. The parents which had the highest number of dominant and ressecive genes for different traits were as follow: For yield lines no. 12 and 14, for plant height lines no. 12 and 9, for ear height lines no. 7 and 13, for ear length lines no. 3 and 6, for ear diameter lines no. 8 and 14, for number kernel per row lines no. 7 and 6, for number of row per ear lines no. 13 and 1, for number kernel per ear lines no. 8 and 1, for 100-seed weight lines no. 8 and 2, for cob percent lines no. 10 and 9, for kernel weight per ear lines no. 12 and 2 and for moisture percent lines no. 12 and 11.

To study genetic of some characters in bread wheat lines under dryland conditions, a diallel crossing design was conducted. Six lines were crossed unilaterally in spring of 2001. In the following year, parents and F1s were evaluated in RCB design with three replications in the Agricultural Research Field of Lorestan University. Plant height, heading date, leaf angle, leaf rolling, chlorophyll fluorescence, flag leaf length, awn length, plant biomass weight, number of seed per spike and spike harvest index were measured. Analysis of variance showed significant differences for all characters except for number of seed per spike and spike harvest index. Data were analyzed by Griffing (method II and model II) and Hayman's methods (Morley and lones method). General combining ability (GCA) was significant for all characters except for chlorophyll fluorescence. Specific combining ability (SCA) was also significant for all characters except for plant height, awn length and plant biomass weight. In general, genes additive effects revealed the effectiveness of selection for plant height. Additive and non additive effects together were effective for selection in segregating population for heading date, leaf rolling, flag leaf length and awn length. Finally non-additive effects were effective for chlorophyll fluorescence and leaf angle

Four advanced lines of wheat which had appeared to be resistant to yellow rust in past years, along with the susceptible cultivar Bolani were intercrossed in one-way diallel cross. Seedlings were grown in greenhouse until the first leaves fully expanded and then inoculated with two pathotypes (race) 6E130A+and 166E42A+of yellow rust, separately. Infection types were scored 18 days after inoculation. Diallel analysis was done by two methods of Griffing, and links and Hayman. Results of analysis of variance of Wr + Vr and Wr - Vr, regression analysis of Vr and Wr and estimates of genetic parameters indicated the importance of additive and dominance effects with pathotype 6E130A+ and importance of additive, dominance and epistatic effects with pathotype 166E42A+. Broad-sense and narrow-sense heritability of infection type were estimated 97% and 58% for pathotype 6E130A+and 99% and 81% for pathotype 166E42A+, respectively. Line M-78-16 possessed the greatest general combining ability to decrease infection type and therefore was suggested to be included in breeding programs for resistance to yellow rust.