JOURNAL OF CROP BREEDING
Year:2014 | Volume:6 | Issue:13|Papers Count:9

Combining ability and heritability of yield and yield components of sunflower (Helianthus annuus L.) breeding lines was studied using line×tester analysis. Eight lines and six testers which were tolerant to plasmopara (Plasmopara halstedii) disease were crossed in line × tester method.48 F1 single cross combinations along with their parents and two checks including Azargol and SHF81-85 were planted in simple lattice design with two replications. The results of analysis of variance revealed significant differences among the genotypes for all the traits including plant height, life-cycle duration, duration of flowering, grain yield, seeds per head and oil yield. Line×tester analysis based on Comstock and Robinson design II displayed significant effects of genotypes, parents and hybrids for all the studied traits. For growth period, RF81-25, AF80-488/1/2/1 had significant negative general combining ability effects. For duration of flowering, RF81-30, AF80-533/1/1/1 had also significant negative general combining ability effects. For seeds per head, RF81-25, AF80-488/1/2/1 and also for seed yield and oil yield, RF81-150/1 and AF80-488/1/2/1 maintained significant positive general combining ability effects. The crosses including AF80-460/2/1/1× RF81-25 and AF-6937×RF81-30 had significant positive specific combining ability for seed and oil yield. Maximum heterosis effects for seed yield were belonged to AF80-960×RF81-25.

Different tissue culture techniques of Digitalis nervosa staud & Hochst were studied. In this study, different kinds of plant growth regulators and sources of carbon (sucrose, galactose, fructose and maltose) were used to investigate the callus induction by leaf explants. Growth regulators 2, 4-D and NAA at three levels and BA at two levels were applied. Murashige and Skoog culture medium supplemented with sucrose, 0.5 mgl-1 BA and 1 mgl-1 NAA was found to be the best treatment for callus induction from leaf explants. In comparison with other culture media callus was appeared sooner on MS medium containing 1 mgl-1 BA, 1 mgl-1 NAA and 2 mgl-1 2, 4-D. The cotyledon explants were the best samples for callus induction compared with the other explants (leaf, hypocotil and root). Hormones BA and NAA were used to investigate plantlet regeneration from leaf based callus. Treatment containing 2 mgl-1 BA was the best choice to shoot regeneration from leaf explant. Murashige and Skoog culture medium acted better than B5 for regeneration. Hormone IBA was used at two levels (0.5 and 1 mgl-1) for root induction. It was determined that there is no significant difference between these two treatments.

The lemon balm (Melissa officinalis L.) a perennial medicinal plant, of Labiateae family is grown in the most parts of Iran and it has shown the sedative, hypnotic, analgesic, antiviral and antimicrobial effects. In present study, genetic diversity of 14 landraces of balm with two out group landraces (basil and moldavian balm) was investigated. Study variation within and between landraces of balm ITS (Internal Transcribed Spacer) region was used to design markers. Also four enzymes Taq1, EcoR v, BssM1 and AspLE1 were used for investigating polymorphism in ITS region. Enzyme BssM1 showed the polymorphism in number and length of digested fragments better than other enzymes. Mantel test results showed that the most correlation was existed between of dice dissimilarity matrix and Neighbor joining algorithm for data analysis. Among balm landraces highest degree of dissimilarity (0.44) was observed from Esfahan and Qazvin landraces and the lowest from 1, 6 and 10 landraces were quite identical. Diversity was observed just for five of landraces (3, 7, 8, 9 and 11). Results of cluster analysis separated landraces on eight groups and Basil genetic distances were less than moldavian balm to the balm and highest distance between groups 3 and 6 with 0.42 and the most similarity was between groups 1 and 4 (dissimilarity=0.15).

Ocimum basilicum L. (sweet basil), from Lamiaceae family, is rich in aromatic essential oils and valuable in industry for its pharmaceutical, aromatic properties. The present study has focused on tissue culture of O. basilicum using leaf explants from in vitro germinated plants. The current study has been fulfilled based on completely randomized design with 5 replications using MS (Murashige and Skoog) medium with different concentrations of BAP (0, 1 mgl-1) and 2, 4-D (0, 0.5, 1mgl-1). After callus formation the calluses were transferred on new MS media with (1, 3 & 5 mgl-1) BAP in combination with 0.2 mgl-1 NAA, for regeneration. The highest average number of shoots occurred in the medium containing 1 mgl-1 BAP and 0.2 mg-1 NAA. The presence of NAA inhibited root formation, when combined with different concentrations of BAP.

In order to increase beet cyst nematode resistance gene frequency, one population named 261* (20314*W-1009) that contains Hs1pro-1 was used in present research. In first year, the population was planted in selection plotes in field. Single plants were labeled and leaf samples were prepared. Then DNA extraction from leaves was done and molecular analysis of plants containing resistance gene accomplished using STS marker and specific PCR test. In second year, gall signs onto resistant vernalized roots were noted and the roots were planted under cages in isolated plots to produce S1 seeds. The S1 seeds were sowed in greenhouse for molecular analysis and in the steckling field to produce the roots. The roots were vernalized in the field in winter season. The molecular results of the S1 plants by Hs1pro-1 marker showed that presence of the resistant gene among the S1 lines is varied 25 to 63 percent. In third year, the vernalized roots were planted under cages in isolated plots to produce new S1 seeds. The new S1 seeds were grown in greenhouse for molecular analysis. The molecular results of the new S1 plants by Hs1pro-1 marker showed enhancement of the resistant gene among the S1 lines that varied 39 to 80 percent. The results showed that resistance gene frequency can be increased by increasing in selfing number and genotypic selection by molecular marker.

In the process of hybrid rice seed production program, initial assessment of the traits related to out crossing levels in male sterile lines for selecting the favorite lines is necessary. Therefore, the study of seven cytoplasmic male sterile lines (released by IRRI) together with their maintenance and 33 male sterile lines derived from backcrossing program (released by Iran) were compared using a randomized complete block design with three replication. Analysis of variance indicated significant differences among the studied lines in 1% level for all characters. Mean comparison of traits showed that male sterile Hasani-awn-Red has the longest length of stigma (2.93 mm) and shortest length of anther (1.87 mm). Out crossing percent was very low in Hasani-awn-Red A and the Khazar A lines. IR69224A line with complete pollen sterility, had out crossing percent (`x=%37.79). Pollen sterility, number of florets per panicle, legume and stamen length traits have been high genotypic coefficient of variation, inheritance, genetic progress. These traits can be used as selection criteria for cytoplasmic male sterile lines without high crossing. Also, out crossing with traits such as anther length (r=0.47), panicle exertion rate (r=0.32) and floret length (r=0.22) had a significant positive correlation. Thus cytoplasmic male sterile lines with anther length large, floret size and complete panicle exertion will be more products of hybrid seed.

Faba bean (Vicia faba L.) is a grain legume that grown for its high protein seeds, which is using as human food and animal feeding. Genetic variability of the traits is important in breeding programes, so that selection gain depends on the existence of genetic variability of traits. Therefore, an investigation was carried out to select the most successful faba bean genotype (s) and to assess the genetic diversity related to the morphological and agronomical traits in some of faba bean genotypes at two locations in Guilan and Lorestan provinces. Results of combined analysis of variance revealed that genotype ×environment interaction effects were significant for all of the studied traits, thus evaluation of the genotypes carried out separately in two environments. Results of analysis of variance indicated that the studied genotypes differed significantly for all of the traits at two environments. Orthogonal contrast indicated that large seed and small seed genotypes were significantly differed for all traits and the eight genotypes were classified in two groups. Two genotypes including the landraces from north of Iran and breeding variety (Barrakat) had the highest yield at Guilan and landraces from Khoramabad produced the highest yield at Lorestan. Results of present study showed that the small seed genotypes from west of Iran and large seed genotypes from north of Iran could be used as parents to obtained transgressive segregation for most of traits.

Ten promising alfalfa ecotypes were evaluated in normal and salty conditions. Various agro-morphological traits of ecotypes such as plant height, number of stem, chlorophyll (CHL) amounts and yield were measured in normal and salt stress conditions. Analysis of variance showed that the responses were significantly different among ecotypes. To ensure results accuracy and ecotypes selection, the experiment was repeated once again and salinity treatments were applied at two levels. The results indicated that the response was significantly different among cultivars. Gara-Yonje, Baftan and Leghlan ecotypes were the best for plant height, however, the results for number of stems were similar. Gara-Yonje and Leghlan had the most CHL but Khaje ecotype produced the shortest height. In salt-free conditions, Gara-Yonje, Khaje and Baftan had the most individually fresh yield. Gara-Yonje and Baftan were the best in moderate salty conditions. Ecotypes in severe salty conditions for fresh yield were similar to moderate conditions and again Gara-Yonje, Khaje, Baftan and Leghlan were the best. Considering all measured traits, particularly with emphasis on yield, Gara-Yonje, Khaje, Baftan and Leghlan can be selected for moderate and severe salty conditions.

In order to estimate gene action of yield and yield components characteristics such as Spikelet Number per Spike, Biomass Weight, Kernel Number per Spike, Seed weight of 10 spikes, Hectoliter Weight, 1000 kernel weight and Yield, six genotypes of bread wheat such as: Arvand, Atrak, Zarrin, Karaj-3, Mv-17 and Navid were used in a 6×6 half-diallel cross. The crosses among the parents were down in 2009-2010. The experiment was conducted in a randomized complete block design with three replications at the research station Mahidasht Kermanshah, Iran in 2010-2011. Data were analyzed using diallel method. Analysis of variance showed significant differences (P<0.01) among the genotypes for all studied traits. Regression coefficient and epistasis tests showed fitness of additive-dominance model for most of the traits except grain yield, 10 spikes weight and seed weight in 10 spikes. Results of Hayman analysis showed that contributions of additive and non-additive effects were involved in control of the traits. Hayman’s graphical analysis showed that A and B parameters were significant at 1% levels. The highest and the lowest heritability of traits belonged to hectoliter weight and 1000 grains weight, were 57% and 13%, respectively. Regarding presence of additive effects for understudy materials and cumulative effect of genes help early generations, screening of cultivars and it, in turn may improve yield and its components.