Production of Salt Tolerance Dwarf Napier Grass (Pennisetum purpureum cv. Mott) Using Tissue Culture and Gamma Irradiation

ABSTRACT As high as 95% of callus was induced when young leaves of dwarf Napier grass were cultured in MS medium supplemented with 5% coconut water and 2 mg/l 2,4-D. These calli were of highly compact type. Upon transferring these calli to grow on the plantlet induction medium, it was found that the MS medium containing 5% coconut water, 1 mg/l NAA, 0.5 mg/l BAP and 0.5 mg/l 2,4-D gave the best average plantlet production of 58.8%. Irradiated calli at the levels of 0, 10, 20, 30, 40 and 50 Gy were subject to culturing growth on the selected plantlet induction medium containing different NaCl concentrations of 0, 0.5, 1.0, 1.5 and 2.0%. The total of 108 clones could survive in the salt supplemented medium. These surviving clones were then transferred to grow in the field at National Corn and Sorghum Research Center, Nakorn Rachasima province. Twenty-one of good characteristic clones were selected from the field to be further grown at high salinity soil in Borabue district, Maha Sarakarm province and 8 clones were finally chosen as salt tolerance. DNA fingerprinting patterns of the 21 selected clones were analyzed using AFLP technique with 11 pairs of primers. The patterns were significantly different at high percentage of polymorphism (94.75%). The similarity index among these samples ranged from 0.569 to 0.784 indicating that the morphological difference among them was the result of true mutation induced by irradiation and tissue culturing

Production of Salt Tolerant Ruzi Grass (Brachiaria ruziziensis) by Tissue Culture

ABSTRACT The best medium formula for multiple shoot induction was determined for seed culture of Ruzi grass (Brachiaria ruziziensis). Murashige and Skoog (MS) medium containing 10 mg/l BAP gave the highest average of 7.49 shoots. These shoots were irradiated at different doses of 0, 10, 30 , 50, and 70 Gy and transferred to grow on the selected multiple shoot induction medium having different concentrations of NaCl at 0, 0.5,1.0, 1.5 and 2.0%. It was found that the percentages of shoot survival decreased as the radiated doses increased. However, at the high salt concentration of 2.0% the growth was completely inhibited. All 173 clones of surviving plant were transferred to grow in the natural field at the National Corn and Sorghum Research Center, Nakhon Ratchasima province. A set of replicated plants from this field was also grown under high saline soil at Borabue district, Maha Sarakham province for comparison. Fifteen healthy clones were chosen from these two sites and grown in the high saline soil for one year. Only ten surviving clones were collected from this second growth and propagated as salt tolerant Ruzi grass. Upon testing the DNA fingerprints of the original 15 healthy clones using AFLP technique with 10 pairs of primers, there was no differences in the banding patterns found among them