JOURNAL OF CROP BREEDING
Year:2015 | Volume:7 | Issue:15|Papers Count:15

This study was conducted to evaluate 100 safflower genotypes (Carthamus tinctorius L.) under two moisture stress environments (non-stress and drought stress) during 2012 using a simple lattice design. Results showed that drought stress significantly decreased some traits such as seed yield per plant (21.2%), number of heads per plant (18.7%), oil percent (1.8%) and biological yield (15.3%). Result also indicated that number of heads per plant is the main factor decreasing seed yield under drought stress. The highest genetic diversity was observed for seed yield and its components in both moisture conditions (non-stress and drought stress). The lowest heritability was belonged to biologic index (35%) and the highest was for plant height (89%).Between yield components the highest heritability were belonged to number of seed per head (87%) and 1000-seed weight (85%). According to cluster analysis based on 10 Euclidean distances all of the genotypes were categorized into three groups. Iranian genotypes were separated from other genotypes which largely consistent with the geographic origin. Results indicate some foreign genotypes are suitable for breeding of undesirable traits of Iranian genotypes such as late-maturity and tallness.

Evaluation of sterility stability between male sterile lines for favorite lines selection is necessary to production of hybrid rice program. So that in present research utilization of 7 cytoplasmic male sterile lines (A line) and 33 male sterile lines product of 7th backcrosses of Iranian varieties with IRRI standard male sterility lines. Experiment was based on a split plot to time design in RCBD. Results of variance analysis showed significant line × time interaction for pollen sterility and panicle at 5% level. Pollen sterility means comparison indicated that five varieties Nemat, Shastak mohammadi, Gerde, Hasani rishak ghermez and Khazar in all crosses with standard lines showed complete sterile in 9 evaluation stages and allocated as completely sterile and stable lines that can be used as sources for transforming sterility genes into new varieties. Pollen and panicle sterility percent of means comparison indicated that Hasani A line despite bearing complete sterility in four stages (3, 10, 17, 7 to 14), have partial fertility in three stages (6, 6, 7 in greenhouse) and have been maximum seed production percentage (25.67%) in 2 initial stages of plant. seed production percentage of IR68899A line that shown the most sterility in all stages was 15.67% at high temperature (>24co) and low light (<13.75 h) conditions in greenhouse. Therefore, could be utilized for two line hybrid programs.

In order to evaluate of annual selection effects on quality and quantitative traits as well as traits relations among cotton lines of Varamin cultivar. present study was performed during 2008-2011 at central station of research center of Varamin. Elite lines were selected annually from breeding lines population in view of morphological traits at the farm and then final selection was done based on fiber length and fiber percent as two important traits. The results showed that selection based on both traits together and selection based on fiber length, finally caused to get the same result in term of fiber percent in the next generation while in term of fiber length, the two kind of selections were different, so that in case of simultaneous selection for both traits, the fiber length was decreased in the next generation. Although the correlation between fiber percent and fiber length in the first year was not statistically significant but it was positive, while in the second and third years it was negative and significant. Therefore the character priority in selection could change the kind of this relationship.

A DNA string can be supposed a very long string on alphabet with 4 letters. Numerous scientists attempt in decoding of this string. since this string is very long, a shorter section of it that have overlapping on each other will be decoded. There is no information for the right position of these sections on main DNA string. It seems that the shortest string (substring of the main DNA string) is a proper estimation of the main DNA string. Therefore aims of the present study is demonstrating an evolutionary algorithm for selecting the shortest superstring into a DNA string. The practical problem in current study is the shortest superstring problem (SSP).We solve the problem using particle swarm optimization algorithm (PSO) in evolutionary algorithm level by programming language MATLAB version R2011a. In comparison with solving problem by genetic algorithm, the result of present study was much better than the above mentioned algorithm.

Species of pathogenic fungi Alternaria SPP developed early blight disease on potato. In order to evaluate the resistance levels of wild diploid accessions of National Plant Gene bank of Iran, a factorial randomized complete design with three replications was performed in National Plant Gene Bank under in vitro and greenhouse condition during 2007-2008 and disease symptoms were recorded. Based on area at disease progress curve for each of two pathogenic fungi A. solani and A. tenuissima disease development on five diploid accessions i.e: TN 528, TN 530, TN 531, TN 532, TN 533 and Agria (susceptible chek) experiment has been designed.Analysis of variance result of in vitro and greenhouse evaluation indicated significant effects of pathogens, sample of genotypes and their interaction. In vitro evaluation, symptoms were observed the first and third days after inoculation via in vitro evaluation, in which, continued up to date sixth. By using A. solani accession TN 533 and accessions TN 531 and TN 530 were at lower and higher levels than Agria. Respectively, mean while, by causing A. tenuissima accession TN 528 and TN 533 and TN accessions TN 531 were at semilar and higher level than that of Agria. Disease symptoms during green house evaluation began on the third day and continued until the day twentieth. During this part accessions: TN 533, TN 532 and TN 530 were at the lower levels compare with Agria and accessions: TN 531 and TN 528 were at higher levels when A. solani has been used. When A. tenuissima was applied accession TN 528 was at semilar level and accession TN 533 was in higher level than Agria.

The relationship between some important morphological traits with seed yield in 18 soybean genotypes inclusive three cultivars (JK, May and Cap) and 15 M4 mutant lines were investigated using randomized complete block design with four replications. Results of analysis of variance indicated that there were significant differences between genotypes in all traits except the number of branches per plant. Analysis of phenotypic correlation showed that the seed yield has a positive correlation with total number of pods (0.888) and harvest index (0.709). Four factors were determined by factor analysis, which justified 88.14 % of total variation. The first factor justified 38.89 % of total variation that defined as yield factor. Stepwise regression analysis for seed yield showed 90 % of variation of yield, as a dependent variable justified with number of total pods per plant, harvest index and plant height. These correlation coefficients of studied traits were 0.888, 0.709 and -0.508, respectively. Therefore, these traits can be notability used in soybean breeding programs. In general, result of present study suggested that gamma irradiation negatively affected on plant height. The May-150 mutant line, with the lowest plant height is able to be accounted for the highest seed yield.

In order to evaluate salinity stress effects on differential expression of metallothionein gene, chlorophyll content, TBARM and some agronomic traits in wheat, the experiment has been carried out using split factorial format based on RCBD design with 4 replications in 2008-09.The main factor included three developmental stages (tillering, stem elongation, heading) and sub factors included factorial arrangement of two wheat cultivars (Kavir and Falat) and 4 salinity levels (0, 100, 200 and 300 mM). The seeds have been sown in pots containing perlit and cocopit (2: 1) and were nutritioned with Hogland solution. Leaf samples were taken at three growth stages. The studied traits included shoot dry weight, leaf aria, special leaf weight, growth rate, seed number, seed weight, grain yield, chlorophyll a-b, TBARM, superoxide ion content and metallothionein gene expression. Results of statistical analysis showed significant effects of salinity levels on all traits except special leaf weight. Shoot dry weight and chlorophyll stability showed strong correlation in favor of resume salt stress in Kavir cultivar.Generally, increased salinity stress resulted in high TBARM index. It was almost the same for super-oxide radical specially at heading stage. Metallothionein gene expression showed high correlation with the amount of this radical specifically in heading stage. This was expected given the anti-oxidant role of the gene, and confirmed this gene promoter induced by super oxide radical.

Strawberry is perennial, herbaceous plants belonging to the family of fragaria, with a rich source of vitamins and minerals. The aim of present study was to evaluate the effects of different concentrations of growth regulators including auxin and cytokinin to identify the best hormonal concentration to obtain the highest yield of in vitro produced plantlets from strawberry cv Diamante. Experiment was performed in a factorial experiment based on a completely randomized design, using the basal MS culture medium. In this experiment the effects of different concentrations of BA (0.2, 0.5, 1 and 2 mg/l), IBA (0, 0/1 and 0/5 mg/l) and NAA (0, 0.1 and 0.5 mg/l) alone or in combination with each other for regeneration of shoot tip explants and NAA (0.2, 0.5 and 1 mg/l) and IBA (0.2, 0.5 and 1 mg/l) for rooting were studied alone.Number and length of shoots and roots produced per explants were evaluated. Results showed that the highest number of regeneration obtained from MS medium included 1 mg/l BA. The highest shoot length was found in the combined treatment of BA and IBA (0.5+0.5) mg/l.The maximum rooting was observed in the 1.2 MS medium containing 0.2 mg/l NAA and the longest roots obtained from control treatment.

Drought stress as an abiotic stress causes different biochemical and physiological responses in plants. To study changes in chlorophyll, total soluble protein and antioxidant activity due to drought stress, we conducted an experiment on five durum wheat varieties (selected from the Seed and Plant Improvement Institute in Karaj) at research greenhouse of Imam Khomeini International University in 2010. Five varieties (Seymareh, Karkheh, Dena, Aria and D-79-15) were cultivated in a factorial experiment based on completely randomized design with six replicates in both normal and water stress conditions. The sampling was done at five leaf stage for measuring total soluble protein, catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX) and super oxid dismutas (SOD) enzymes activity. Results showed that total soluble protein increased significantly, but total amount of chlorophyll decreased due to drought stress. Amount of chlorophyll a, b and total chlorophyll for cultivar Aria, was maximum. Also, the results showed that activity of CAT, SOD and POX increased due to stress, while stress caused a decrease in the activity of APX. Cultivar Aria had the highest catalase enzyme activity against drought stress and was considered as drought resistant cultivar. Seymareh had the highest POX activity under stress. The lowest POX activity was for line D-79-15 and was recorded more sensitive to stress than other varieties. Dena and Karkheh showed the highest increase in super oxid dismutas and ascorbate peroxidase enzyme activity under stress condition, respectively.

Wheat (Triticum aestivum L.) is a member of the Poaceae family, an annual and self-pollinated crop which has three groups of 14, 28 and 42 chromosomes with genome formula AA, AABB, AABBDD that the chromosomes are located in three homeologous genomes A, B and D. Wheat has an extremely large genome of 16 ´ 109 base pairs with more than 80% repetitive DNA and an average of 810 mega base pairs in each chromosome with 10 mm length. Wheat is the most important crop in universe and in Iran, known as strategic and basic commodities. This crop plays an important role in both aspects of production and consumption with a lot of genotypes that requires efficient and accurate means of identifying their relationships and determining their genetic diversity levels. Present study aims to determine the genetic diversity and genetic distances of 91 doubled haploid lines of wheat and their parents using SSR markers and assess the ability of microsatellite markers for detecting polymorphisms based on the variants among their germplasm.Results showed that the number of alleles per locus ranged from 2 to 8 and the allelic value of polymorphism information content (PIC) ranged from 0.12 for Xgwm46 to 0.87 for Xgwm186 with an average of 0.5. A total of 39 alleles were detected. Diversity and genetic relationships of the samples were analyzed using Nei and Li and UPGMA statistical methods and the studied lines were classified into three common groups.

In this research to investigate the variation of iron, zinc, calcium, magnesium, ammonium and chloride micronutrient and glutenin subunits allele variation, 33 wheat cultivars and lines were studied in lattice design with two replications during 2011 cropping season. The results of ANOVA showed significance differences among genotypes for all traits with except for seed magnesium and ammonium content. Simple correlation coefficients between seed zinc content with seed iron, ammonium and magnesium content and also correlations between seed iron content with the amount of seed calcium, magnesium and chloride were positive and significant.Cluster analysis based on seed micronutrients grouped the genotypes into three clusters with the highest genetic distance between Sepahan and Line A and the lowest genetic distance between Roshan and Bezostaya. In total, 14 allele combinations and 13 alleles were detected in bread wheat. The Glu-1 loci scores ranged from 5-10, with an average of 6. Fifteen percent of the genotypes had high scores from 8 to 10. The highest frequency at locus Glu-A1 was for subunit Null (81.81%), in Glu-B1 for subunit 7+8 (48.4%) and in Glu-D1 for subunit 2+12 (66.6 %) respectively. In Sorkhtokhm variety the allelic composition at Glu-D1 locus was similar to 2+10 and was named 2.1+10*. Among the cultivars, Saysvn had the highest score (10) for glutenin quality and followed by Pishgam (score 9), Bahar and LineA (score 8). Also line A had the highest amount of iron, calcium and magnesium as well as favorite glutenin quality with scores 8. Consequently, these cultivars could be selected as the parent in crosses depending on breeding goals.

In order to study mode of gene action in rice for the traits related to yield, four varieties of rice were investigated. Direct and reciprocal crosses have been done between parents Sang- Tarrom and Gerdeh, IR229 and IRRI2 and their back crosses. The F1 and BC seeds were grown in 2006 and F1 plants were selfed for obtaining F2 seeds. Therefore, 10 different populations (generations) including P1, P2, F1, RF1, BC1, RBC1, BC2, RBC2, F2 and RF2 were planted in a randomized complete block design with three replications. The Additive´Dominance model was significant for the traits in both crosses (except number of panicle length trait in Sang-e- Tarrom´Gerdeh cross). The join scaling test indicated that the inheritance of traits related to yield was described by Additive´Dominance components, non-allelic interactions mainly Additive´Additive and Additive´Dominance and duplicate epistasis. Estimated of narrow and broad-sense heritability for two crosses was 0.56 to 0.98 and 0.03 to 2.68 respectively. More than one major gene group appeared to be involved for the expression of 1000-grain weight and plant height while the remaining traits showed the presence of at least one major group of genes for controlling their inheritance.

In order to investigate the combining ability of sunflowers lines under normal conditions and drought stress, a study was conducted at the Seed and Plant Improvement Institute, Karaj, Iran in 2006. A total of 41 treatments including 2 CMS and 13 restorer lines as well as their 26 corresponding hybrids were evaluated in two irrigation conditions, in a line ´ tester approach.The analysis of variance indicated that significant differences existed among genotypes, parents, parents against crosses, crosses and testers for most of the studied traits. The effects of lines were significant for days to maturity, plant height and grain yield in non-stress conditions, and for most of the traits in stress conditions. The effect of line ´ testers was significant for seed weight in non-stress condition, and for days to flowering, seed yield, plant height and oil yield in stress condition. Assessment of general and specific combining abilities showed that CMS19 (tester) and CMSb ´ R7 were best line and hybrid in both conditions, respectively.

Genetic diversity is the base of plant breeding. In present study 19 chemical and morphological traits in 36 genotypes were investigated with a 6´6 simple lattice design in Tirtash Education and Research Center. Results showed significant differences among genotypes for all studied traits. The highest and the lowest genotypic variation coefficient were related to percentage of sugar and nicotine, respectively. The highest and the lowest phenotypic variation coefficient were attributed to cured leaf yield and percentage of protein nitrogen, respectively. Broad sense heritability was the highest for percentage of total ash (92.7) and the lowest for percentage of protein nitrogen (13.9) and percentage of Phosphorus (22.2). In factor analysis, six main and independent factors were identified; yield and related morphological characteristics (factor 1), tobacco taste characteristics (factor 2), nitrogen dependent characteristics (factor 3), plant height (factor 4), number of leaves (factor 5) and effective trait on tobacco leaf ripening (factor 6). These factors explained up to 80% of total variation among varieties. Cluster analysis based on Ward's minimum variance classified genotypes into seven clusters including 6, 5, 3, 8, 2, 4 and 8 genotypes, respectively.

In order to evaluate of the effects of induced mutation doses of gamma irradiation 500, 700 and 900 Gry, the M2 generation of two rapeseed varieties including RGS003 and PF, were studied along with control treatments in a randomized complete block design with three replications. Selected lines of third-generation of mutation (M3) were evaluated for plant height (cm), number of pods per plant and seeds per pod, pod length (cm) and 1000 seed-weight (gr). Effect of gamma irradiation doses in most traits were significant for both varieties while, number of pods per plant showed the highest C.V. in PF and RGS003 at doses of 500 and 900 respectively. Results indicated that the traits highly affected from gamma radiation. The PF mutants had the highest C.V. for most traits, showing it is highly affected from gamma irradiation. Mean comparison of the traits showed that four lines of PF and one line of RGS003 indicated better than control plant height, number of pods per plant, seeds per pod and seed weight. Results demonstrated that gamma irradiation is suitable for producing desirable variation and can be used as suitable genetic resources for producing superior varieties.