فصلنامه زراعت و اصلاح نباتات
سال ششم شماره 3 (پاییز 1389)

In this study, sugar beet tissue culture clones were used to screen rhizomania resistant genotypes. At first, explants derived from flowering stem tips of sugar beet were transferred to shoot tip elongation media after surface sterilization. Then, the grown shoots were transferred to media containing various hormonal combinations NAA, BA, IBA, and GA3, for multiplication, growth and rooting. The clones were transferred to the soil and peat moss mixture and then were adapted to greenhouse conditions. For screening clones against rhizomania, the genotypes of adapted clones were selected and inoculated to rhizomania-infested soil. This experiment was done as a completely randomized design with in equal replicates in greenhouse. Adapted plants were transferred to the soil containing rhizomania virus. All infested soils were diluted 3 to 7 with sand. DAS- ELISA test was used for infested plants after six weeks and optical density of the samples were analyzed by SAS program. Significant difference among the genotypes was observed. Genotypes in mean comparisons were classified to a few groups from completely susceptible to completely resistant by SAS analysis and SPSS software. As in this study same genetic based clones has been used, therefore difference between the genotypes was affected in genetic difference of between them and differences within each genotypes resulted in environmental effects. Use of colons having same genotype, resulted in increasing of selection accuracy of resistant genotypes.

Attention to Genetic diversity of wild relative plants important as a natural germplasm that are huge source of genetic diversity, study on wild relative plants is important. So for study of synthetic wheat lines that received from international center for maize and wheat research (CIMMYT), on 2008-2009 season crops an experiment including 69 synthetic wheat lines with seven controls (Bam, Sistan, Bahar, Roshan, Kavir, Pishtaz and Akbari) by Alpha lattice design include 2 replications which have been done in the research filed seed and plant breeding research institute of Karaj. The twenty morphological and physiological traits were measured. The biological yield trait has the highest correlation (r=0.77**) with grain yield. Biological yield, harvest index, plant height, penultimate and grain width are five traits that entered into the stepwise regression’s model and explain %95.2 of data variation. In continue for study on relative among traits, path analysis has been done. It showed that biological yield and harvesting index consecutively have 0.685 ** and 0.569 ** highest and positive direct effects and plant’s height has the highest and negative (-0.174 **) direct effect.

In order to study the genetic control of yield and related traits in corn, a diallel mating with 14 inbreed lines were used. Parents and their F1 generations were evaluated, using RCB design with 3 replications (2007) in Karaj seed and plant improvement institute. Hayman & Jinks method were used to data analysis. Variance analysis indicated that additive and non-additive gene effects were important in traits control. According to average degree of dominance over-dominance gene effect observed for yield, ear length and kernel weight per ear and for one hundred kernel weight and ear diameter were partial dominance. Also the increaser alleles for traits were dominant. Broad sense heritability and narrow sense heritability for yield was 0.67 and 0.25 respectively. For other traits broad sense heritability estimated between 0.65 and 0.85, and narrow sense heritability estimated between 0.29 and 0.55.

In order to investigation the relations among the affective traits on white bean grain yield, a filed experiment was conducted with 46 promising lines of white bean and two improved check cultivars “Dehghan” and “Daneshkadeh” at the research field of Karaj, Seed and Plant Improvement Institute, Iran, in 2008 growing season. The experiment was performed as a randomized complete block design with three replications. The results of the traits’ correlation with the grain yield showed that all the characteristics under investigation have a positive and significant correlation with the grain yield. Among them a remarkable correlation was seen among the grain yield with the number of seeds per plant, the biological yield and the number of pod per plant. In the Regression Analysis, the first trait entering the model was” the number of seed per plant” which justified 73% of the yield alterations by its own. Then these characteristics entered the model respectively: 100 seeds weight, biological yield, pods weight, LAI (R8) and the pod Length and they justified 95% of yield alterations totally. To identify the direct and indirect effects of the traits on the grain yield, path analysis was performed; which showed that the traits of the number of seeds per plant, 100 seeds weight and the biological yield has the most positive and direct effect on the grain yield respectively.

Genetic and environmental factors can affect the performance of the genotypes. Genotypes ×environment interaction can result different reaction of the genotypes in different environments.Therefore,determination of stability of the genotypes in different environments is necessary and important.This study was conducted to determine the stability of 10 winter and facultative bread wheat genotypes in experiment of C-86.The experiment was conducted in 9 experimental stations using randomized complete block design with three replications in 2007-09 cropping seasons.Simple and combine analysis of variance were carried out.Result of combined analysis of variance for grain yield showed non-significant effect for genotype×year and genotype×locations. However,genotypic effect and interaction effect of year×location and genotype×year×location were significant. Eberhart and Russel,Intra-locational variance,Wricke and Shukla method, and simultaneous selection for yield and stability (YS) were used to determine the stability of the genotype.for grain yield,Genotypes 3 and 4 were determined as the most stable genotypes by Eberhart and Russel method. Genotypes 5 and 9 with the low mean variance and high yield were determined as the most stable genotypes by Intra-locational variance method. Wricke and Shukla method showed 9,5and 6 as the most stable genotypes.Using simultaneous selection for yield and stability (YS) showed genotypes 6 and 4 as the most superior genotypes.

Wheat leaf rust (Brown rust) caused by (Puccinia triticina) is a, worldwide major disease of wheat. In this study, three leaf rust isolate from Gorgan, were collected and determined their Avirulence and virulence formula with 39 near-isogenic lines. The results showed that these isolate were avirulence on plants with Lr1, Lr14a, Lr19, Lr25,, Lr23+ Lr28,Lr10+ genes while these isolate had virulence on plant with (Lr 22b, Lr 2a, Lr 2b, Lr 2b, Lr 2c, Lr 3, Lr 3ka, Lr 3bg Lr 9, Lr 10, Lr 11, Lr 12, Lr 13, Lr 14b, Lr 15, Lr 16, Lr 17, Lr 18, Lr 20,Lr 21, Lr 22a*, Lr 23, Lr 24, Lr 26, Lr29, Lr 30, Lr 32, Lr 33, Lr 34*, Lr 35*, Lr 36, Lr 37*, Lrb) genes. In order to evaluate of resistance to leaf rust, 122 advanced lines from Iranian regional program were tested at seedling stage with Gorgan pathotype in greenhouse condition. The experiment was conducted in randomized complete block design (RCBD) with three replications. The latent period (number of days from inoculation to appearance of the first uredia) and infection type were recorded by McIntosh et al; 1995 method. Analysis of variance showed significant difference between 122 genotypes for infection type and latent period in Gorgan, indicates that there are more diversity between genotypes with pathotupe Gorgan.. The results of analysis cluster lines showed division to thrre groups resistance and mid resistance and susceptible. Lines No. 23 and 78 were the more resistant and susceptible, respectively.

In order to determine stability and reaction of durum wheat promising genotypes in dry and warm region of Iran, 18 durum wheat promising lines in 5 stations including Khorramabad, Ahvaz, Darab, Dezful and Zabul, along with commercial bread wheat and Karkheh cultivars as checks, based on randomized complete block design (RCBD), with three replications and two croping season (2007-2009) were evaluated. To evaluate genotype-environment interaction and determine of stable genotypes, ten stability statistics were calculated (ib,2diS,2Ri,Di,DI,iS,iPEG,i􀁔,(i)􀁔and GAI). Based on the results of the above statistics genotypes 1, 3, 5, 14, 16 and 17 in most methods showed varying degrees of the general stability. In general, genotypes 3 (AJAIA_12/F3LOCAL (SEL.ETHIO.135.85)//...), 5 (NUS / SULA / / 5 * NUS/4/SULA/RBCE_. ..), 14 (CNDO / PRIMADUR / / HAI-OU_17/3/SN TURK MI83-84 375 /...) and 16 (ADAMAR_15//ALBIA_1/ALTAR 84/3/SN TURK MI83-84..) with the average yield of 6.009, 5.926, 5.912 and 6.186 tons per hectare, respectively, had a better general stability and adaptability, consequently, these genotypes are advisable for dry and warm climate in Iran.

Sowing date is an important affecting factor on yield in rape seed (Brassica napus L.). However, the magnitude of yield reduction caused by delay in sowing has been poorly defined for different environments, in Kermanshah province. The present study was conducted to determine the effect of date of planting on grain yield and oil content in five cultivars of rape seed during 2000-01, and 2001-02 cropping season at moderate climate of Kermanshah, Islam Abad. The cultivars were compared in 4 different sowing date in a split plot design with 4 replications. Four sowing dates (27 August, 10 September, 25 September and 10 October) were considered as main-factors and the five cultivars (Orient, Tallaye, Okapi, SLMO 46 and Colvert) as the sub-factors. The combined analysis of variance indicated highly significant differences among the sowing dates and the cultivars. Other traits including: days to flowering, flowering period, plant height, days to maturity, seed per pod, oil content of seeds, were also different among the treatments. The effect of sowing date on yield, days to complete flowering and their interaction were different at 1 % level of significance. In the first sowing date (27 August), period of maturity and yield component were increased. In the first and the second sowing dates, the yield were highest with 3952 and 3478 kg/ha, respectively.Though the oil content was not increased in the first sowing date, but it was compensated for higher yield production. The highest grain yield were obtained form Orient and Cobra with 3289, 3235 respectively. The highest oil content belonged to Orient and Cobra, with 44.57% and 44. 2%, respectively.