Abstract
Haploid plants of Nicotiana alata were cultured in vitro on MS medium with IAA + KIN. The resulting plantlets were irradiated using gamma radiation doses of 10, 15, 20 and 25 Gy. Single node pieces were cut and transferred onto fresh MS medium. Gamma radiation doses caused the death of 9% and up to 28% of explants. NaCl concentrations caused the death of 8% up to 36% of explants, while the combined effect between gamma radiation doses and salinity had an impact suffused on the percentage of survival. The combined effect of gamma radiation doses 20 Gy and 25 Gy on NaCl concentrations of 100, 150 and 200 mM were deadly. Even more, the combined effect of gamma radiation doses and salinity had a severe negative impact on both the proline content and total soluble protein. Random amplified polymorphic DNA (RAPD) analysis was used to determine the degree of genetic variation in treated haploid Nicotiana alata plants. Total genomic DNAs from different haploid plantlets treated were amplified using five arbitrary primers. Two hundred and seventy bands were detected from plantlets irradiated with doses of 15, 20 and 25 Gy, with polymorphic band number 226 (83.7%). The total number of bands resulted from plant grew on 150 mM and 200 mM NaCl were 260 bands with polymorphic bands 185 (85.6%). However, the total number of bands produced from combined effects between gamma rays and salinity (20 Gy X 50 mM NaCl, 20 Gy X 100 mM NaCl and 25 Gy X 50 mM NaCl) were 270, with polymorphic band number 231 (85.5%). High similarity between treatments was revealed. Treatments relationships were estimated through cluster analysis (UPGMA) based on RAPD data.
Highlights
Nicotiana genus is one of the five major genera of the Solanacae family
The aim of the present study was to investigate the induction of genetic variability using gamma radiation and selection for salt tolerance based on the similarity of the Random amplified polymorphic DNA (RAPD) technique data, undertaken to distinguish Nicotiana alata diploid and haploid plants treated with gamma radiation and/ or salinity and to detect genetic diversity among them
The irradiation doses had a negative impact on shoot length as shown in Fig. 1, where the shoot length decreased with increasing gamma radiation dose (5.1, 4.5, 3.9 and 3.2 cm respectively)
Summary
Nicotiana genus is one of the five major genera of the Solanacae family. Nicotiana sp. has been cultivated for thousands of years and served as a medicinal herb, trade commodity and crop plant by different cultivars. Has been cultivated for thousands of years and served as a medicinal herb, trade commodity and crop plant by different cultivars. Nowadays, it became one of the most important commercial crops in the world. More than 800 million hectares of land throughout the world are salt-affected (including both saline and sodic soils), equating to more than 6% of the world’s total land area (FAO, 2008). In Iran, Pakistan, Egypt and Argentina, out of the total land area of 162.2, 77.1, 99.5 and 237.7 million hectares, about 23.8, 10, 8.7 and 33.1 million hectares are salt-affected, respectively (FAO, 2008). It was estimated that the world is losing at least 3 ha of arable land every minute because of soil salinity (FAO, 2008)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
