Influence of Nitrogen Source for the Improvement of Shoots and Roots on in vitro Strawberry (Fragaria ananassa DUCH)

Abstract

In vitro techniques are important tools for modern plant improvement programs to introduce new traits into interested plants, to multiply elite selections and to develop suitable cultivars in a minimum time. The standardization of protocol and procedure of micropropagation of strawberry was successfully attempted by many researchers. Crops are very sensitive to various ratios of NH4+: NO3 in the nutrient solution. Presented study was conducted to determine the effect of nitrogen source on shooting and rooting stage of strawberry (Fragaria X ananassa Duch.) var. chandler by changing the concentrations of NH4NO3 and KNO3 in MS nutrient medium formula to improve protocol for the high rate of in vitro propagation of strawberry. Results showed that decreasing the concentration of NH4NO3 from 1650mgl¹ to 825 mgl¹ combined with KNO3 at 1900 mgl gave the highest results in shoot number, shoot length and growth vigor during multiplication stage. While in rooting stage MS nutrient medium without KNO3 and NH4NO3 at 1650 mg1¹ the highest root number, root length and shoot length were achieved. Management of culture medium composition is very important to obtain high quality from micropropagated plants.