SEED AND PLANT IMPROVEMENT JOURNAL
Year:2012 | Volume:28-1 | Issue:4|Papers Count:13

To study grain yield stability and adaptability of eighteen barley genotypes comparing with two national check cultivars, an experiment was carried out in eight cold region agricultural research stations Arak, Ardebil, Hamedan, Jolgeh Rokh, Karaj, Miandoab, Mashhad, and Tabriz during two consecutive cropping seasons (2005 and 2006). The experimental trials were based on a randomized complete block design with three replications. To study genotype × environment effects, GGE biplot method was used. Based on the polygon of GGE biplot method for grouping environments, the genotype no. 16 (G16) in Arak and Hamedan, genotype no. 17 (G17) in Karaj, Miandoab and Mashhad and genotype no. 4 (G4) in Ardebil and Jolgeh Rokh had the highest yield. Based on the tester biplot results, the environments of Karaj, Mashhad and Miandoab were closer to the ideal tester environment and based on the biplot of genotypes and environments and ideal genotypes biplot overall, the promising line no. 17 (MAKOUEE//ZARJOW/80-5151) was recognized as the best genotype examined in terms of being a high yielding and stable genotype. Based on these results it can be concluded that although breeding stable and adaptable cultivars for such a vast climatic zone has its own difficulties, it is possible to seek for the genotypes with both narrow and wide adaptations through the information extracted from the multivariate stability analyses.

To study the genetic diversity and determine the role of morphological traits in determination of relationship between different species of wild lentil, 96 accessions of wild lentil collection of NPGBI from Lens nigricans, L. ervoides and L. odemensis were characterized according to instruction of IPGRI. Twenty four morphological traits were assessed. Statistical parameters of traits were calculated and coefficient variance percentage and Shannon index were used to estimate genetic diversity. The results of descriptive statistics showed a considerable variation among and between different accessions. Among quantitative traits, 100 seed weight (CV= 114%), rachis length (CV= 55%), rachis to peduncle length ratio (CV= 49.5%) and the number of pod per peduncle (CV= 33%) had the most, and calyx length and leaflet width (CV= 25%) had the least variation in different species. Based on Shannon index, in qualitative traits, stipule shape (1.02) and pod pigmentation (0.92) showed high variation. But pod dehiscence and shedding had lower variation. In multivariate analysis of quantitative and qualitative traits, morphological characters could almost distinguish L. ervoides from two other species. Considerable similarities especially in qualitative traits were observed in Lens nigricans and L. odemensis accessions so they could not be differentiated by these characters.

In the present investigation, eight accessions belonging to three species of Stipagrostis were subjected to cytogenetic analyses. Results of chromosome count showed two ploidy levels of diploid (2n=2x=22) in S. plumosa and tetraploid (2n=4x=44) in S. pennata and S. karelinii. The chromosome number (tetraploid) of S. karelini is reported for the first time. Karyotypic formula obtained in the studied populations mostly included metacentric chromosomes. Satellite and nucleolus organizer region (NOR) were observed in diploid populations of S. plumosa. Karyotypic analysis and grouping of karyotypes with Stebbins method classified diploid population into 1A and 2A and tetraploid populations into 1B karyotypic classes. Considering this classification it could deduced that tetraploid populations containing asymmetrical karyotype. Analysis of variance of karyotypic traits showed significant differences for short arm length, arm ratio and centromeric index that indicating chromosomal variation among the studied genotypes. The highest correlations were observed between short arm with long arm, centromeric index with total form percentages and centromeric index with value of relative chromatin content (r = 0.96, 0.88 and 0.87, respectively). The results of cluster analysis and Romero Zarco coefficient grouping were consistent and divided the populations into two separate groups. First group included three diploid populations from S. plumosa and the second group included tetraploid populations from S. pennata and S. karelinii species.

Ten local hazelnut genotypes named Gerduii, Gercheh, Shastak, Payizeh, Mahali Karaj, Tabestaneh, Rasmi, Shirvani, Pashmineh and Gerde Eshkevarat were evaluated based on guidelines of Distinctness, Uniformity and Stability (DUS) during years 2008-2009 in Kamal-Shahr Research Station in Karaj. Three 16 years-old trees from each genotype were selected and 55 traits including 3 traits from trees, 3 from one-year-old shoots, 9 from leaves, 6 from flowers, 24 from fruits and 9 complementary traits including pests and diseases resistance were recorded. Fourteen quantitative traits (length, width, length × width, thickness of one-year-old shoot, length and width of petiole, length and dimensions of leaves, male flower length, fruit weight, length and diameter and percentage of kernels) were significantly different among genotypes. Based on four qualitative traits, all genotypes could be differentiated well. Regarding quantitative fruit traits, Gerduii was determined as a superior genotype having thin shells, large kernels, and easily separating shells from kernel and was a multipurpose genotype. Pashmine, Gerduii and Gerche had round fruits and were suitable pollinizers for other genotypes. This information could be used for hazelnut orchard establishment and breeding programs.

To determine mode of action of the genes affecting important agronomic traits and seed shattering resistance in soybean, progenies derived from crosses between Telar and T215, including F1, F3, BC1, and BC2 together with P1 and P2 were evaluated in Karaj. The results indicated that for all the traits, genes action with dominance effects, followed by additive effects had the most impact on the genetic performance. There was a high similarity in inheritance of the reproductive-related characters such as flowering initiation with starting stage of seed filling, completion of seed filling with seed maturity, seed yield with yield components especially with pod number per plant and plant height with number of node per stem. Dominance effects in seed shattering were more important than the additive effects. However, epistatic effects could not be ruled out. [d], [h] and [i] effects were significant for majority of agronomic traits and [j], [l] interaction effects were significant for a few traits. Inheritance mode of flowering initiation (R1) was similar to initiation of seed filling (R5), compelet seed filling (R6) was similar to compelet maturity (R8), seed yield was similar to its components and plant height was similar to number of nods. Seed shattering had single gene inheritance but different epistatic effects inpressed expersion of the character.

In order to study drought tolerance in 21 advanced bread wheat genotypes and two check cultivars Azar 2 and Alvand, an experiment was conducted using randomized block design with three replications under drought stress and supplementary irrigation during 2008-09 cropping season at Maragheh research station, Iran. The combined analysis of variance showed significantly differences among the genotypes over the environments. Significant differences were also found among the environments and GE interaction effects. The large magnitude of the GE interaction related to genotypic effect, suggested the possible existence of sub-environmental groups for the genotypes. The GGE (G + GE) biplot analysis was able to differentiate of environments to sub-environmental groups with top yielding genotypes as highly adapted genotypes to each environmental group. Based on GGE biplot, the genotypes No. 9 (Sabalan/4/VRZ/3/ORFI.148/TDL/BLO) and 11 (BAYRAKTAR) can be recommended as genotypes which integrating yield with stability performance and the genotype No. 12 (F10S-1//ATAY/GALVEZ87) was highly adapted to supplementary irrigated environment. Lines No. 3 (Azar 2/78Z hong 291-99) and No. 12 with 2691 and 3597 kgha-1 under drought and supplementary irrigated conditions respectively produced the highest grain yield. Two irrigations increased 9.2g TKW, 652kgha-1 yield, 6.4cm plant hieght and 5.6% harvest index compared to drought condition. Under supplementary irrigation 1mm irrigation increased 8.15 kgha-1 grain yields.

Lack of heterogenesity in commercial populations of common button mushroom Agaricus bisporus, hinders the analysis of breeding systems in this valuable species. With the aim of producing a heterogenous segregating population which can be used in breeding programs, slow growing isolates were derived from 10 commercial strains. Out of 377 slow growing isolates 22 proved to be homokaryotic. Homokaryotic isolates were assessed for their similarity using nine RAPD primers. Similarity analysis revealed high polymorphism among homokaryons. Based on the similarity matrix isolates with the least similarity were crossed. Out of 92 crosses, seven proved to be compatible and resulted in stable heterokaryons. The seven hybrids were recognized as the segregating maternal population.

Eighteen pulm cultivars including ten Iranian native and eight foreign cultivars were evaluated based on 36 parametric and non-parametric characteristics and 15 RAPD primers. The results of analysis of variance showed significant differences among the cultivars for all characteristics except the petal color. Dissimilarity matrix revealed that two cultivars Mashhad 4 and Dirras-e-Seif and two other cultivars Ontario and Barbang were distinctly different considering their quantitative and qualitative characteristics. Cluster, constructed from morphological data in distance of 25, classified cultivars into two major groups. Cluster analysis could differentiate the Iranian and foreign cultivars in some extents. Molecular data generated a high percentage of polymorphic bands (99.04%), and the similarity matrix of these data showed the highest similarity between Emprofrance and Bokharaye Marghob (71%) and the lowest similarity between Shiro and Bokharaye Mamoli (9%). The cluster constructed from molecular data clustered cultivars from 0.15 to 0.85 genetic similarity coefficient. In the similarity distance of 0.26, the cultivars were divided into three groups where the Dirras-e-Seif cultivar exclusively comprised an indipentent cluster and was distinguished from other cultivars. In valuation of plum cultivars based on morphological and RAPD primers, although Iranian and foreign cultivars were clearly differentiated, but in some cases they showed some differences.

The resistance of 72 wheat genotypes from collection of National Plant Gene Bank of Iran was assessed to yellow rust in two hot spots of Sari and Karaj, Iran. Both experiments were performed in augmented design and traits of infection type, disease severity, area under disease progress curve (AUDPC) and coefficient of infection were recorded. Based on t-test, two hot spots were significantly different for disease severity (at the first and third evaluations), infection rate (first, second and total), coefficient of infection (first and third) and AUDPC (second and total). Standard deviation of the resistance traits increased by time at both hot spots. Cluster analysis of resistance components grouped AUDPC distinctly at both hot spots. The results of regression analysis indicated strong association of AUDPC with disease severity, infection type and coefficient of infection at both hot spots. Infection rate had higher broad-sense heritability compared to other components of resistance, totally in two hot spots of Karaj and Sari. The results of Mantel test for consistence of distance matrices of accessions based on resistance components at two hot spots along with other results of the research indicated the importance of each components of partial resistance in reaction of the studied accessions to yellow rust. Cluster analysis by resistance components placed the genotypes in two groups of susceptible and partially resistant.

In order to study the pathogenic variability in Puccinia triticina Eriks (Pt), population and for identification of physiological races, during early spring of 2009 and 2010, more than 140 infected leaf samples were collected randomly from different wheat growing areas in Iran. In each sample, some single pustules were produced. In total 234 single pustules were used for seedling race analysis of which, 177different virulence classes (races) were identified. Three leaf rust races FKTRS, FJRRS, and FKTTS were highly frequent among identified races. The maximum number of virulence factor for 31 Lr genes was found for races TKTTN and TFTTN that were collected form Ardebil and North Khorasan, respectively. In spite of the high diversity in Pt population in Iran, gene Lr19 was susceptible only to one race (FHQJS) and Lr2a to seven races. Based on the results of this study, combination of leaf rust resistance gens with low frequency of virulence(such as Lr9, Lr28, Lr25, Lr19, Lr29, and Lr2a) with the Non-race specific adult-plant resistance genes (Lr34, Lr46or Lr67) could be used for development of durable leaf rust resistant cultivars. Existence of the identical races especially in the adjacent provinces along with the existence of air flows on this way reinforced the reason of linking of these provinces through air flows. This relationship was both in grouping based on being virulent or non-virulent on the seedlings of wheat near isogenic lines and in the abundance of the races. The aggressive isolates in rather similar groups showed the relation between the provinces. Almost most of the provinces were related to each other. This suggests the vast gene flow and effective transmission of spores through air flows.

Mahaleb (Prunus mahalab L.) is used as a rootstock for cherries in Iran and many other countries. In this research, RAPD markers were used to determine the genetic diversity among eight genotypes of Mahaleb evaluated in two separate research grardens in Karaj, Iran. These genotypes are used as mother plants for seed production. Totally 40 random primers were examined for PCR reactions on the template DNAs extracted from leaves, of which 12 primers producing polymorphic bands between genotypes were selected. These 12 primers produced 73 bands, among them, 30 were polymorphic. The highest similarity (0.82) was detected between genotypes no. 4 (Gen4) and 7 (Gen7) and the lowest similarity (0.26) between genotypes no. 2 (Gen2) and 5 (Gen5) with genotype no. 8 (Gen8). In another trail, 16 morphological traits were recorded for these genotypes. Resulted morphological cluster, divided these genotypes into three clusters. In plot analysis gnotypes Gen4, Gen1 and Gen2 were separated from others.

A breeding hexaploid salt tolerant wheat line (MS-81-14) was produced from crossing of an Iranian salt tolerant wheat line (1-66-22) with Inia cultivar (from CIMMYT) at Karaj Research Station in 1991-92 cropping season. The F1 plants were grown at Karaj in 1992-93 cropping season, furthermore F2-F6 populations were evaluated under salinity stress conditions (EcSoil&Water = 8-12 ds/m) in Isfahan (Rodasht Agricultural Research Station) during 1993-1999 cropping seasons. An extracted breeding line was evaluated in the preliminary yield trial of Yazd and Neishabour Stations and was picked based on its high yield as well as its good performance under salinity stress conditions in 1999-2000. This line was further tested in the preliminary regional yield trial of salt affected regions of temperate zone at two stations (Yazd and Isfahan) and with recorded yield of 6.483 tha-1 against 4.893 and 4.400 tha-1 of Kavir and and Roshan check cultivars, respectively was selected again in 2000-01. This line was tested in advanced and replicated trials over four stations (Yazd, Zabol, Kerman and Isfahan) in 2001-02 and with recorded grain yield of 5.55 tha-1 compared to 4.145 and 4.185 of Kavir and Roshan check cultivars, respectively under salinity stress conditions, as a superior line forwarded to adaptation trials. The adaptation and stability of this line were evaluated in a two years experiment tested over three stations (Yazd, Birjand and Isfahan) during 2002-2004 periods under salinity stress conditions (EcSoil = 8-14ds/m, EcWater= 8-12 ds/m), and with grain yield of 5.470 tha-1 against 4.650, 4.499 and 4.962 tha-1 of Kavir, Roshan and Bam check cultivars, respectively and due to its high stability (with Ys=23 against Ys= 8,7 and 17 of Kavir, Roshan and Bam check cultivars, respectively), high adaptability and good bread quality was considered as the most stable line for on-farm and extension trials which was followed in 2004-08 over different salt affected regions of temperate zone showing an average grain yield of 4.232 tha-1 for MS-81-14 against 3.673 and 3.769 tha-1 of Bam and Kavir check cultivars, respectively. The results of farmer conditions trials confirmed the wide adaptability and grain yield stability of the new line. Considering high grain yield, high adaptability and stability for saline areas and good grain quality (protein contents of 11.9% and hardiness index of 50 as well as good agronomic performance including resistance to lodging and shattering, this line named Arg and officially released in 2009 for cultivation in saline areas (with water/soil saline) farms of temperate zone, in Iran.

Line WB73-6 (Trompillo, CMB74A-432-25B-1Y-IB-1Y-OB) was first introduced in Iran through a nursery received from CIMMYT in 1989. It was selected in a preliminary experiment in Zabol research station among the genotypes of IBON in 1990. In other preliminary and advanced yield trails carried out in Zabol and other stations in southern provinces of Iran with warm climate in 1991-1997, line WB73-6 produced higher grain yield than other advanced lines and check cultivars and showed also good adaptability and yield stability. The global mean grain yield of this line in these experiments was 4902 kgha-1, which was 404 kgha-1 higher than that of the check cultivars. The most specifications of this line are geneal compatibility, high tolerance to loding and diseases, moderate tolerance to grain loss, tolerance to axis breaking, tolerance to drough and high temperature in late growth stages, high 1000 kw (42 g) and high seed protein contents (12%). In on-farm trials carried out in three locations in Zabol and two locations in Khuzestan province during 1999 and 2003 cropping seasons, its grain yield was 350-580 kgha-1 higher than the yield of check cultivars. This line was officially registered in Iran by the National Cultivar Release Committee of Agricultural, Education and Extension Organization with the name of Nimrooz in 2009.