Iranian Journal of Genetics and Plant Breeding
Volume:2 Issue: 1, Apr 2013

Transferring foreign genes into mushroom mediated by Agrobacterium tumefaciens is a standard technique in genetic engineering. Recombinant human insulin has been greatly used in the treatment of type I diabetes. The production of edible mushroom derived insulin should facilitate oral delivery. In this study we used the Agrobacterium tumefaciens mediated transformation method for the transfer and expression of the cholera toxin-B subunit (CTB) fused with human pro-insulin (Pins) in the edible oyster mushroom، Pleurotus ostreatus. The binary vector pCAMBIA1304 harboring CTB-Pins gene driven by the P. ostreatus gpd promoter was constructed and introduced into P. ostreatus via Agrobacterium tumefaciens mediated transformation. Optimization of gene transformation and tissue culture conditions is one of the most important issues in transgenic mushroom production. For attaining optimized conditions، the effects of co-cultivation conditions، Agrobacterium strains and the concentration of Agrobacterium cell suspensions were studied. Integration of CTB-Pins into mushroom genome was confirmed by PCR. The successful transformation to oyster mushroom suggests that the proposed modified transformation system is apparently useful for the production of human pro-insulin in these edible mushrooms.

Mineral nutrient malnutrition، particularly deficiency in zinc and iron، afflicts over 3 billion people worldwide. Biofortification of food crops is the best approach for conciliating the micronutrient deficiencies. Understanding the genetic basis of their accumulation is the preconditions for enhancing of these micronutrients. In our study، a mapping population of a set of 118 recombinant inbred lines (RILs)، derived from a cross between an Iranian local variety ‘‘Tabassi’’، and a European elite variety ‘‘Taifun’’ were analyzed for grain iron and zinc contents. The grains of the RILs population were measured for Fe and Zn concentrations using atomic absorption spectrophotometer. The grain Fe and Zn concentrations in the RILs population ranged from 9. 65 to 71. 4 and 44. 35 to 95. 6 mg/kg، respectively. An available linkage map، comprising of 205 simple sequence repeats (SSR) markers and three morphological loci as well، comprising 26 linkage groups، was used for mapping QTLs of interest. For the grain Fe concentration، six significant QTL (LOD≥2. 5) were detected on chromosomes 2A، 3D، 4D، 7B، and 7D explaining 29. 1% of the phenotypic variations of the trait. For the grain Zn concentration، two significant QTL was detected on chromosomes 1A and 4A explaining 51. 45% of the phenotypic variations of the trait.

Glucose oxidase is an important enzyme hydrolyzing for its hydrolyzing activity on glucos. It possesses and has a wide board of applications in different industries such as bakery، pharmaceutical، plant pathology and biosensors. In this study، yeast (Saccharomyces cerevisiae) was transformed successfully by the glucose oxidase gene (gox) obtained from Penicillium funicolusum. The secreted glucose oxidase enzyme (GOX) by yeast transformants was characterized intra and extracellularly. The effect of different pH values، carbon sources and the duration of cultivation time on the gene expression were also studied in liquid and solid media. Results indicated that the produced enzyme had the maximum activity of 41and 38 U/ml for the intra and extracellular، respectively in pHs ranging between 4. 5-5. 5 at optimum temperature of 30°C after 3 days of yeast culture. Galactose was found to be the most efficient carbon source than the other sources and the maximum activity of target enzyme was observed at 1% (w/v) concentration of galactose. The presence of glucose in the culture media depressed the production of GOX. However، a high rate of growth of the yeast and the high yield of the target enzyme suggested its potential for application in the industry.

Generally، narcissus is propagated through vegetative methods، but due to their low yield their are not economical. This study was conducted to develop a suitable method for the production of somatic embryos and bulblets in Narcissus papyraceus cv. Shirazi. Bulb scales were placed on the MS medium supplemented with 2،4-D and BAP each at 0. 0، 0. 25، 0. 5 or 1 mg/l concentrations to form somatic embryos (SEs). For proliferation، the bulblets were cut in small segments and placed on either MS medium supplemented with sucrose at 30، 60 or 90 g/l، kept in dark or light intensities of 54 or 108 μmol m-2 s-1 or the MS medium including Methyl jasmonate (Me JA)، growth retardants Paclobutrazol or Cycocel (PBZ or CCC) each at 0. 0، 0. 5، 1. 0 or 2. 0 mg/l. The highest SE percentage (75 ± 9. 0) was obtained when 1. 0 mg/l 2،4-D and 0. 5 mg/l BAP were incorporated into the medium. Using sucrose at 60 g/l under a light intensity of 54 μmol m-2 s-1 or utilizing 1. 0 mg/l PBZ produced the greatest bulblet number (4. 45 ± 0. 51 and 5. 0 ± 0. 25، respectively). None of the scales produced bulblets in dark at any sucrose concentration

In this study، Simple Sequence Repeat markers (SSR) were used to investigate the genetic variation between 49 cumin ecotypes collected from 9 different provinces of Iran. SSR primers Elap1479، Elap040 and Elap1493 showed the highest (89%)، while Elap1340 and Elap017 showed the lowest (56%) number of polymorphic bands. Polymorphism information content (PIC) values varied between 0. 18 - 0. 37. The highest and the lowest PIC value were obtained by Elap017 and Elap1340 (0. 37) and Elap040، Elap1493 and Elap1479 (0. 18)، respectively. Cumin populations of Semnan and Northern-Khorasan showed the highest difference، whereas Kerman and Esfahan populations exhibited the lowest difference. The obtained dendrogram classified all cumin population into three clusters at similarity level of 0. 71; the first group was Semnan and Southern-Khorasan populations، the second includes Fars، Kerman، Northern-Khorasan، Khorasan-Razavi، Esfahan، Golestan and the third class consisted of Yazd populations. Based on these clusters، Kerman and Northern-Khorasan showed the closet genetic background and may belong to the same ancestor. The genetic markers used in this study can provide impetus information for tagging of economic traits. It can be concluded that the variability in the Iranian cumin populations have potential important source for cumin breeding objectives.

In order to study the inheritance of some traits related to grain yield in drought stress conditions in bread wheat (Triticum aestivum L.)، F2، F3 and F4 generations derived from a Kharchia (tolerant) × Gaspard (susceptible) cross and their parents were used separately in a complete randomized block design with two replications. Stem length، biological yield، main spike straw weight، total spike straw weight، grain yield as well as harvest index were measured in different generations. The results of the analysis of variance showed that generations mean squares were significant for all traits. Therefore، the generations mean analysis was performed for all of the traits. The model of four-parameter including m، [d]، [h] and [i] was significantly fitted for the majority of the traits. Although both types of additive and dominance effects were involved in the control of the studied traits but dominant component was more effective than the additive one. Dominance effects and additive × additive epistasis were more important than additive effects and other epistasis components for most traits. Regarding the existence of additive and non-additive effects in controlling studied traits، the recurrent selection followed by pedigree breeding can prove useful in improving drought tolerance in bread wheat.