Study of genetic variations in local germplasm of alfalfa (Medicago sativa L.) using random amplified polymorphic DNA (RAPD) technique
Author
Al-Hinai, .Saleh Ali Said
English abstract
This investigation was carried out to study morphological and agronomic characteristics and to estimate genetic variations of 15 alfalfa (Medicago sativa) accessions. Genetic diversity was analyzed using Random Amplified Polymorphic DNA (RAPD). Seeds of the indigenous alfalfa accessions were collected from different regions in Oman and sown under field conditions at Sultan Qaboos University Experiment Station in Muscat. Plants were evaluated for their height, fresh and dry matter weights for two consecutive cuts as well as their re-growth rate after the first cut.
Results showed that Sur accession was more productive with respect to green and dry matter weights either per plant or per hectare. Sohar accession had the lowest green and dry matter weights per area. Saham accession showed the highest leaf number while Al-Kamil had the lowest. Salalah accession had the highest average plant height while Sohar had the lowest.
Generally, all accessions were taller and produced higher green and dry matter weights per plant and per hectare in the second cut than in the first cut. All accessions had greater plant re-growth rate in the second week than in subsequent two weeks. They had higher plant re-growth rate in the third week than in the fourth week except for Sohar where there was a decline in re-growth rate. Bahla II and Yanquol II exhibited rapid re-growth following harvest whereas Manah accession showed low re-growth rate.
Bulked samples of genomic DNA from 24 alfalfa plants per accession were used as templates in polymerase chain reaction with d produce RAPD patterns. Using eight RAPD primers, 70 bands were scored as present or absent across the accessions. Genetic identity between accessions ranged from 0.6429 to 0.9429. The highest level of genetic diversity was between Ibri and Hamra whereas the lowest level of genetic diversity was found between Manah and Sur.
The dendogram constructed through cluster analysis illustrated seven clusters encompassing 14 accessions. Sohar did not group directly with other accession, Ibri and Dank were tightly clustered and formed a distinct branch on the dendogram.
