Molecular Plant Breeding
Ghasem Mohammadi-Nejad; Rakesh Singh; AbdolMajid Rezaie; Ahmad Arzani; Babak Nakhoda; Mohammad Hossein Fotokian; Ali Moumeni; Glenn Gregorio
Volume 1, Issue 1 , March 2012, , Pages 49-59
Abstract
This research was conducted to validate and fine map the region attributed to salinity tolerance on chromosome1 in rice (Saltol) at International Rice Research Institute (IRRI) during 2005 to 2007. A major effect QTL (Saltol) which is responsible for Na+ and K+ uptake and their ratio was identified using ...
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This research was conducted to validate and fine map the region attributed to salinity tolerance on chromosome1 in rice (Saltol) at International Rice Research Institute (IRRI) during 2005 to 2007. A major effect QTL (Saltol) which is responsible for Na+ and K+ uptake and their ratio was identified using F8 recombinant inbred lines (RILs) of Pokkali/ IR29 cross on chromosome 1. This QTL explained around 64.3 to 80.2% of the phenotypic variation for the mentioned traits. Fine mapping was done using 10 SSR and EST-SSR markers and near isogenic lines (BC3F4), derived from IR29 × Pokkali that were produced for this trait. Random BC3F4 individuals were genotyped and phenotyped under two different electrical conductivities at seedling stage. QTL responsible for salinity tolerance at both ECs, were found in the same place in Saltol region, which explained 18 and 24% of the phenotypic variation for SES scores, respectively. According to the present results, possible location of Saltol was found in the interval around 1.2 cM on chromosome 1 that could physical map. It was around 350Kb. This QTL was mapped at the intervals of RM8094, RM3412 and CP6224. Therefore, molecular breeding for salinity tolerance in Iranian genotypes could be done using the mentioned markers.
Biotic and Abiotic stress
Gholamreza Salehi Jouzani; Sepideh Akbari Vala; Mehdi Sabet Jahromi; Hassan Morsali
Volume 1, Issue 1 , March 2012, , Pages 61-75
Abstract
Commonly, plant roots colonized by arbuscular mycorrhizal fungi (AMF) can tolerate different stresses such as soil salinity. Thereby, identification of the dominant AMF species in the saline soils and their application as biofertilizer is very useful for increasing crop productivity in such conditions. ...
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Commonly, plant roots colonized by arbuscular mycorrhizal fungi (AMF) can tolerate different stresses such as soil salinity. Thereby, identification of the dominant AMF species in the saline soils and their application as biofertilizer is very useful for increasing crop productivity in such conditions. For this purpose, sampling was performed from root and rhizosphere of wheat, barley and weeds in Yazd, East Azerbaijan, Qom and Markazi provinces. The morphological properties of spores of the isolated AMFs were studied. Then, samples were screened using a two steps nested PCR methodology. At the first step, AMF-specific primers, including LSU-Glom1 and SSU-Glom1 were used, followed by Alu1 restriction of PCR products, and then at the second step, the restricted PCR products were amplified by fungal universal primers (ITS4 and ITS5) for amplification of ITS-rDNA region. The PCR products were cloned, and restricted by Taq 1. The results of morphological charectreristics and analysis of the achived sequences and blasting showed that two AMF genus, including Glomus (more than 90%) and Acaulospora (10%) were domininat. The species G. mosseae (50%), G. intraradices, G. sinosum, G. constrictum, G. etunicatum, G. versiforme, G. fulvom, and Glomus sp were identified using molecular strategy. The maximum species diversity was observed in the fields of Yazd Province and rhizosphere of wheat. Totaly, results of the present study showed that the species G. mosseae has the highest dominancy and adaptivity in saline conditions, so after performing further experiments, it can be used as a source of biofertilizer in such regions.
