VARIABILITY AND RELATIONSHIPS BETWEEN STA INING ABILITY OF POLLEN ANDSEED-BREEDING CHARACTERISTICS OF HYBRIDS LOLIUM-MULTIFLORUM LAM X FESTUCA-ARUNDINACEA SCHREB IN F3 GENERATION

In a set of hybrid plants of F-3 generation from five combinations of crossing of Italian rye-grass (Lolium multiflorum Lam.) and tall fescu e (Festuca arundinacea Schreb.) and cultivation of hybrid embryos in i n vitro conditions the following indicators were assessed: staining ab ility of pollen grains, number of inflorescences per plant, germinatin g capacity of caryopses, weight of 1,000 caryopses weight, number of g erminative caryopses per inflorescence and weight of germinative caryo pses per plant. Staining ability of pollen was determined as indirect fertility via acetocarmine method. The results were assessed by the me thod of multivariate selection of genotypes (Tab. I) and tightness of relationships expressed by variation coefficients (Tab. II). It follow s from Tab. I that individuals of high fertility (staining ability) of pollen and simultaneously high weight of germinative caryopses per pl ant were rather exceptional. In four hybrid plants only the weight of caryopses exceeded 50% of value of an ideal individual. Within the set an average staining ability of pollen was 76.2%, germinating capacity of caryopses ranged from 4.3% (420/3 in plant) to 97% (417/2), weight of 1,000 caryopses from 1.56 g to 4.15 g and number of germinative ca ryopses per inflorescence amounted to 0.3% up to 27.8%. It follows fro m a free relationship between staining ability of pollen and number of germinative caryopses per inflorescence and weight of germinative car yopses per plant (r = 0.14 and 0.21) that staining ability of pollen i s a little suitable indicator of prediction of seed formation in hybri ds Lolium multiflorum x Festuca arundinacea. Based on the highly posit ive correlation found out between pollen fertility and germinating cap acity of caryopses (r = 0.46(xx)) it can be presupposed that in hybrid plants of high degree of staining ability of pollen grains, caryopses of high germinating capacity will be produced. A weak dependence betw een staining ability of pollen grains and caryopsis formation was conf irmed in investigated hybrids as reported by Kaiser (1988) and other a uthors in hybrids Lolium multiflorum x Festuca pratensis. A wide range of variability recorded almost in all studied traits allows further s election.