JOURNAL OF PLANT GENETIC RESEARCH
Year:2017 | Volume:4 | Issue:2 |Papers Count:6

Tomato leafminer (Tuta absoluta) is one of the important pests of tomato in Iran. It causes serve losses to tomato yield between 50 to 100% in the world. The cryIAb gene has been introduced into many plant species, including maize resulting in protection of the maize plants against corn borer larvae. In most studies, constitutive promoters such as CaMV35S were employed for genetic transformation; however the constitutive expression of genes led to changes in plant metabolic pathways due to permanent energy consumption in plants. Since, wound inducible promoter MPI (Maize Protease Inhibitor) posses more efficiency and strength than CaMV35S promoter. Therefore, in the current study, transgenic tomato (cv. Falat) plants harboring cryIAb gene under control of the MPI promoter were developed for the first time. The MPI promoter was isolated from maize and cloned into pPZP122 expression vector replacing the CaMV35S promoter. The cryIAb gene was isolated from pCIB4427 and cloned in pPZP122: MPI: cryIAb and the resulting construct was transformed into Agrobacterium AGL1 strain using In planta approach. Initial selection of the transgenic plants was carried out in media culture containing gentamicin. PCR analysis confirmed the presence of transgene in gentamycin-resistance plants in the first and second generations by rate of 62.5% and 75.58%, respectively. Protein dot blotting using anti-CryIAb polyclonal antibody confirmed the presence of protein in the second generation of transgenic lines. Based on the result of Tuta bioassay, transgenic plants demonstrated an enhanced resistance against Tuta. Thus, the wound inducible promoter MPI can be used in genetic transformation of crop plants if insecticidal protein-encoding genes (such as different types of cry) are used and therefore, it is important to be used when plants asked to express only when are being attacked by insect pests.

Evaluation of genetic diversity in medicinal plants is one of the most important evolutionary and breeding goals. Recent developments in polymerase chain reaction brings the possibility of evaluation the individuals of a population in more sites of genome, and among different DNA molecular markers, the ISSR marker was successfully used in study of the genetic diversity of different plants. The genetic diversity of 43 individuals from five populations of Styrian Pumpkin (Cucurbita pepo var. styriaca) and 4 individuals from one population of C. maxima which cultivated in Shahid Beheshti University collection (Tehran, Iran) was investigated using 12 ISSR markers. Totally, 83 scorable bands were produced by ISSR markers and the mean for the produced band for each marker was 6.91 and 100% of scorable bands were polymorphic. Dendrogram was illustrated based on Jaccard coefficient similarity matric and algorithm of Complete Linkage. Based on cluster analysis, individuals of populations divided into five main groups. The results of the grouping through principal coordinate analysis and cluster analysis showed that groupings by the two mentioned methods were consonant with each other and have made a similarity grouping. The cophenetic coefficient was calculated as 0.97. Totally, the results of present study showed that the some of used ISSR markers could be useful for future study of genetic variation in Cucurbita pepo.

Black stem disease is one of the most important fungi diseases in sunflower. Information about the mode of heritability and the effects of genes controlling trait could be most important for selecting breeding methods to black stem disease resistance. In this study, genotypes ENSAT-B5 and AS613 and a mutant genotype M5-54-1 with different response to MP8 and MP10 isolates were selected and F1, F2, BC1 and BC2 generations were made from ENSAT-B5×AS613 and ENSAT-B5×M5-54-1 crosses. Generations of crossing and parents of each set were planted in a completely randomized design with three replications and infected by M8 and M10 isolates. With the exception of the [(♀) M5-54-1 × ENSAT-B5 (♂) -MP10] cross, the lack of fit test of simple three parametric additive-dominance models for the [(♀) AS613 × ENSAT-B5 (♂) -MP8] and [(♀) AS613 × ENSAT-B5 (♂) -MP10] crosses were significant, indicating the presence of non-allelic interactions in the inheritance of the black stem disease resistance. In the estimated models for the different crosses, high and significant amount of dominant effects and dominant × dominant interactions suggested the importance of non-additive genetic effects. Therefore, selection for this trait in early generation could not be effectively successful and hybrid development is highly recommended for increasing the resistance to the black stem disease.

Drought stress is one of the factors that reduces yield in the world. Considering that wheat is grown mostly in semi-arid areas, much attention has been paid to develop drought tolerant varieties. This experiment was conducted during 2013-2014 in Tabriz University research farm, Iran. In this investigation the inheritance of some agronomic and physiological traits was studied in the field condition through generations mean analysis. The generations were produced from the cross of Arg (tolerant to drought) and Moghan3 (sensitive to drought) varieties. The experiment was a split plot design based on randomized complete blocks with two replications. The irrigation conditions were arranged in the main plots and generations in the subplots. In the stress condition, irrigation was withheld after pollination. Based on the analysis of variance, significant difference were observed among different generations in terms of plant height, peduncle length, flag leaf length, flag leaf width, number of fertile tillers, leaf chlorophyll content, leaf temperature, days to maturity, spike weight, straw weight, biomass, grain yield and harvest index. The interaction between generations and irrigation conditions was significant only for grain yield. The generation mean analysis in both normal and drought stress conditions showed that chi-square of three parameter model was significant for all of the studied characteristics, indicating the presence of non-allelic interactions in the inheritance of these traits. The broad sense and narrow sense heritabilities for the traits under study were estimated as 0.502-0.946 and 0.244-0.429 in the normal condition and 0.653-0.951 and 0.221-0.377 in the water stress condition, respectively. The average degree of dominance for all of the characters in both normal and water stress conditions was greater than one which indicated the existence of over-dominance gene action in controlling these traits. At both conditions, the dominance genetic variance was higher than the additive genetic variance for all of the traits. The results indicate the necessity of selection in advanced generation or exploiting dominance gene action in the breeding programs, if hybrid varieties are produced in the wheat plant.

Drought stress is one of the most important factors involved in reducing wheat production and identifying genetic structure and gene action type in controlling grain yield in water stress condition is essential for choosing appropriate breeding methods. In this study, 9×9 one way diallel crosses were used to study the genetic structure of wheat grain yield at stress and non- stress conditions. Combining ability analysis by the second Griffing method for both conditions resulted in significant GCA and SCA variances, representing grain yield may be controlled by additive and non- additive effects of genes. The results of applying combining ability analysis indicated that among the parents, genotypes Ghods and Bam had the highest GCA for grain yield and the best specific crosses were Arg × Ghods, Navid × Moghan, Bam × Alvand (for both irrigation regimes) and Bam × Ghods (in stress condition). Biplot analysis of diallel data was used to display GCA and SCA for parents and to determine heterotic groups and the best crosses. In general, according to the results, Bam, Ghods and Arg were tolerant cultivars and had the ability to maintain yield in drought stress condition as well as to transfer these properties to the hybrids. So these genotypes can be used to improve stress tolerance in breeding programs.

Breeding of adapted and variation germplasm can be a main element for strength of research political in stable agricultture system. This is achived by targeting variety selection onto different growing environments under natural heat and drought stresses. To realize this, breeding programs usually undertake a rigorous genotypes performance evaluation across locations and years mostly at the final stage of variety development process. More accurate selection of wheat genotypes requires reducing environmental effects for explaining of their genetic potential with appropriate analysis of genotype × environment. In this research, 18 improved bread wheat genotypes were planted in randomized compelet block design with 4 replications in Gachsaran, Khoramabad, Gonbad, Moghan and Ilam stations during three years (2011-2014). Simple and combined analysis variance were done on grain yield data. Due to significant interaction effects for Year × locatin and genotype × year × locatin, yield stability of considered genotypes were analysed using some parameteric and nonparametric methods. Obtained results showed genotypes no.10 and 17 with 3107 and 3028 kg/ha had the highest grain yield. Based on parametric statistics: CVi, Wi2, si2, qi, MSY/L and MSPI and non-paramertric statistics: Si(2), Si(3), Si(6), Top, Mid, Low,, R-Sum, and SDR, G10 had more yield stability. More over, G12 and G17 showed suitable yiled stability among high production genotypes. Earliness Genotypes 10 and 17 lines had optimum plant height and partially high thousand kernel weight.