BIOCHEMICAL AND MOLECULAR MARKERS FOR INVESTIGATING THE MODE OF REPRODUCTION IN THE FACULTATIVE APOMICT POA-PRATENSIS L

Isozymes and random amplified polymorphic DNA (RAPD) markers were used for precocious identifi cation of non-maternal plants in progenies of the facultative apomict Poa pratensis. Four progenies obtained from c ontrolled crosses that showed different degrees of apomixis on isozyme analysis of phospho-gluco-isomerases, esterases and peroxidases were chosen for RAPD analysis to generate genomic fingerprints using specie s-specific primers. At an advanced vegetative stage, a morphological a nalysis was also performed and characteristics related to growth habit and leaf morphology were observed and recorded. On the basis of the i sozyme and RAPD electrophoretic pattern and the morphological appearan ce, each plant was classified as maternal or aberrant. All three class es of genetic markers employed were able to identify plants that exhib ited aberrant traits in the four progenies. Overall, the results of RA PD analysis supported those of isozyme and morphology studies. However , in each progeny, some plants which both isozyme and morphological an alyses distinguished as of maternal origin were aberrant according to RAPD analysis. Therefore, the RAPD method proved the most precise scre ening technique. The greater cost of the molecular approach was offset by its higher accuracy. The use of either three isozyme systems or si x primers for PCR amplification seems to be sufficient for reliable es timation of the degree of apomixis. Histological analyses were carried out and the aposporic development of the plant material studied.