فهرست مطالب محمدرضا راحمی

Potato (solanum tubrusum) is the fourth staple food after rice, wheat and corn. It is the most important tuberous crop. Potato color flesh is one of the most important parameters in food industry and marketability. The flesh color of the tetraploid cultivars range from white to cream and yellow to dark yellow. There are a few cultivars with red or blue/pink flesh color. Based on mutant clones containing superior quantitative and qualitative traits and flesh color change in Caesar potato variety, this research was carried out with the aim of determination of the reason of color flesh change in Caesar mutant.

Mutant and parent (Caesar) clone were cultivated in research farm of Ardabil Agriculture Research Center in 1397. Sampling was done in 4 replications for each clone. Changes in total carotenoid and its components were performed by spectroscopy-UV and HPLC-chromatography, respectively.

Carotenoid content in mutant clone was 319.54(µg/100 FW) and in parent clone was 246.36 (µg/100 FW). This result showed that content of total carotenoid in mutant was 1.3 times the carotenoid content of the parent. HPLC results showed that Lutein content was increased in mutant in comparison to parent, whereas, violaxantin was higher in parent that mutant clone.

Based on our results total carotenoid content along with lutein play an important role in potato color flesh change. Our finding is in accordance with results of other researches that showed that flesh color change from cream (parent) to yellow (mutant) was affected by total carotenoid content generally and lutein specifically.

This research is aimed to evaluate and investigate the performance stability of superior promising cotton genotypes that have been obtained through various breeding methods including hybridization and mutation and were superior rather than their parents in the Hashemabad region of Gorgan.

In this experiment, six genotypes A-NBK, A-NB414, A-SKG, A3-96, Va-1, and Va-2 along with control cultivar (Golestan) were evaluated in the form of randomized complete block design with 3 replications during three years (2017-2019). A Combined analysis of variance, cluster, and principal component analysis methods using graphical analysis of genotype in traits were used to analyze data.

Based on the results of the combined ANOVA, the investigated genotypes were not significantly different in the traits of the number of reproductive branches and the yield of the first picking. Despite, height, number of bolls, percentage of early maturity, yield of 30 bolls, total yield, yield of fibers (30 bolls), length of fibers, uniformity, finess of fibers, strength, elongation of fibers, total keel and keel of 30 bolls was significantly different among genotypes. A-NB414 genotype had a highest of 110.3 cm and the Golestan variety had the lowest height (83.7 cm). The yield trait of the second harvest of genotype A-NB414 (1283.2 kg/h) and the total yield trait in genotype A-NB414 (5067.1 kg/h) were significantly higher than other genotypes. Based on the results, three components had roots of more than two (7.79, 2.76, and 2.49). The results of cluster analysis were classified into 3 groups.

The results showed that A-NBK and A-NB414 genotypes can be introduced as new cultivars and also be used in breeding programs to create higher genetic diversity. It can be obtained by crossing the A-NBK genotype with the Golestan cultivar to a desirable variety due to the different genetic background. Genotype Va-1 appeared as an early genotype with high fiber uniformity and high first-harvest yield. A-NB414 and A-NBK genotypes with high height, boll number, fiber uniformity percentage, and high yield among the studied genotypes are suitable for introduction as a new variety.

Despite the new varieties of cotton that have been improved, introduced and marketed in recent years thanks to the efforts of cotton breeders, increasing the genetic diversity of the country's gene bank and introducing new varieties with higher yield, earlier maturity and better fiber quality. This study was conducted to evaluate the agronomic and quality traits of cotton varieties bred using different breeding methods that have shown their superiority over commercial varieties in one or more traits in Hashem-abad region of Gorgan. This research was conducted to determine the effectiveness of the measured traits of cotton genotypes.

In this study, 5 genotypes 90-10481, 92-34, 92-48, Va-1, and Va-2 were compared along with controls Golestan and Varamin in the form of a randomized complete block design with three replicates in 2018-2019 by using the combined analysis method and principal components analysis with GTBiplot graphical analysis and selecting the best genotypes.

Based on the results of combined analysis of height traits, number of sympodial branches, number of bolls, percentage of earliness, yield (30 bolls, first picking, second picking) and total yield, fiber yield (30 bolls), of seed weight (30 bolls and first picking), fiber length, uniformity, fiber fineness, firmness, fiber elasticity, total percent lint, and percent lint of 30 bolls were significant at the 1% statistical level when genotypes were examined. According to the obtained results, four components had a higher root than two (5.88, 5.27, 3.12 and 2.05). The first four components explained 90.65% of the total changes between the data. In the first component with a value of 32.65, early maturity and weight of 30 bolls traits, in the second component number of bolls and total yield, in the third component fiber length and strength traits, and in the fourth component fiber elongation and fineness traits and percent lint explained the changes. The greatest variation shown by the biplot diagram in genotypes Va-1 and VA -2 in traits related to yield included total yield, number of bolls, yield at first picking, yield at first picking, and earliness. VA -genotypes Va-1 and VA -2 are positively correlated with each other and negatively correlated with genotypes 92-48, 90-10481 and 92-34 and Golestan cultivars. VA -1 genotype has a zero correlation with the varamine variety, since they have an angle of about 90 degrees. Therefore, VA -1 genotype and Varamin variety have different genetic background that causes their differences.

The results show that the Va-1 and Va-2 genotypes are capable of introducing new varieties and can also be used in breeding programs to create greater genetic diversity. In addition to their high yield, they were earlier than the other genotypes studied. Genotype Va-1 proved to be an early maturing genotype with high uniformity of fiber and high yield at the first harvest. Genotype Va-1 had the highest yield among the studied genotypes with a high number of bolls and sympodial branches. These traits can be taken into account in breeding programs to improve commercial varieties and to produce new varieties.

 The objective of the research was to evaluate six newly introduced cotton genotypes for some quantitative and qualitative traits, distinctness, uniformity and stability (DUS) to assess potential crop production and agronomic ability as new varieties, and to establish a reference collection of morphological traits for the purpose of identifying the necessary morphological descriptors for genetic purity and determining the authenticity of the varieties in the subsequent control of commercial seed production.

 Seed cotton yield, number of bolls per plant, boll weight, and earliness of 34 quantitative and qualitative morphological traits of six new promising genotypes of Uplandcotton (Gossypium hirsutum L.): 1- SK6, 2- GKSK4, 3-96_A3, 4- GKTB113, 5- ANBK and 6- ANBK414 compared with control cultivars: 1- Varamin and 2- Golestan in 2019 and 2020 according to the International Guidelines for the Conduct of Distinctness, Uniformity and Stability (DUS) Tests evaluated as a complete block trial with four replicates.

 The new genotypes ANB414 and ANBK had the highest cotton seed yield and the highest number of bolls per plant, and the new genotype 96_A3 was the earliest genotype. In addition, the new genotypes ANB414 and GKTB113 had the highest fiber length and extension and were superior to the control cultivars and other genotypes studied. The new cotton genotypes resembled the control cultivars in 12 qualitative morphological traits and differed from other new genotypes in 22 qualitative morphological traits.

 The results of the quantitative traits studied showed that the new genotypes ANB414 and ANBK had the highest cotton seed yield and the highest number of bolls per plant, while the new genotype 96_A3 had higher earliness, while the new genotypes ANB414 and GKTB113 had the highest fiber length and extension compared to the control varieties. In addition, the studied new cotton genotypes were distinguishable based on various studied morphological characteristics compared to each other and to the control cultivars and had uniform and stable distinctness. Therefore, the studied new cotton genotypes are potentially suitable for introduction as new varieties.

Study of genotype (G) × environment (E) interaction and identifying of stable and high yielding cultivars are important and essential component of cotton breeding programs dedicated for cultivar development.

Nine new promising cotton genotypes (Gossypium hirsutum L.) along with two commercial cultivars (control) were evaluated in a randomized complete block design (RCBD) with four replications at eight locations including Hashemabad, Karkandeh, Darab, Khodafarin, Garmsar, Varamin, Isfahan and Moghan during two crop seasons (2018-2019).

Combined analysis of variance (ANOVA) across environments indicated significant variation among genotypes and G × E interaction for seed cotton yield. Significant G×E variation allowed for subsequent analysis of genotype stability statistics and AMMI analysis. Regarding AMMI analysis, two principle components contributed for 81.0 % of the variation among the G×E interaction. The Varamin and 92-34 genotypes have shown general adaptability with average yield across environments. The Golestan, ANBK and ANB414 were identified as high yielding and the most stable genotypes based on parametric models (Cvi, bi and Xi), AMMI and GGE Biplot models. It was concluded that AMMI biplot clearly facilitate identification of mega-environments and cultivars for specific recommendations.

The results of study indicated that ANB414, ANBK and Golestan could be suited for cultivation across the test environments.

The genome of a plant is the most critical factor to control bakery- quality trait in wheat, where it can bemade by applying genetic variation upon using mutagens for its improvement. In this study, chemical and Farinograph experiments were investigated in T-66-58-60, O-64-1-10, RO-1, RO-3 and RO-5 lines from Tabassi, Omid, and Roshan cultivar, respectively. Also, the sigmoid transfer function was used for the assessment of factors by the model of feed-forward neural network with training method of levenberg-Marquardt algorithm. The chemical traits of Zeleny number, the hardness, wet gluten and protein content in the RO-3 line increased significantly compared with the control. Also, water absorption percentage and valorimeter value increased substantially in the O-64-1-10, whereas it was shown that the dough softening after 10 and 20 minutes decreased significantly compared with the control. The protein content, bread volume, Farinograph quality number and E10 properties had the most significant impact on the neural network model. The results show a positive effect of the irradiation on the improvement of dough quality properties.

Wheat is regarded as a strategic product among the cereals in the world. The bread quality of this product is affected by the physical and chemical properties of wheat gluten. In order to achieve lines with superior qualitative characteristics, gamma irradiation was applied on Roshan cultivar with high cultivation area in a cooperation between Atomic Energy Organization of Iran and the International Atomic Energy Agency. To investigate the effect of gamma irradiation on morphological characteristics and yield, Roshan and mutant lines were grown in the farm of Zaferanieh in the Karaj city with four replications in 2016. Morphological and agronomic features of Roshan and mutant lines such as height, peduncle length, height and number of panicle, leaf area and yield were measured. After harvesting, physical and chemical properties of Roshan and the mutant lines including chemical tests (protein percentage, Zeleny number, bread volume, seed moisture percentage, seed hardness and wet gluten), Farinograph (leavening time of the dough, Farinograph quality number, dough stability, the degree of softening after 10-20 min for dough, and the valorimeter value) and Extensograph (resistance of maximum, resistance strength after 5 min, extensibility, relative resistance and the area under the curve which represents the amount of energy required for stretching the dough) tests were assessed. The results showed that Zeleny number, hardness, wet gluten and protein content increased significantly in Roshan3 line as compared with the control. Farinographic characteristics indicated that water absorption percentage, dough stability and valorimeter value increased significantly, while dough softening trait after 10 and 20 minutes reduced significantly in Roshan3 line as compared with the control. Roshan3 line increased significantly rather than the other investigated genotypes. Mutation breeding be able to improve qualitative traits in crops.