POLLEN PISTIL INTERACTION IN MAIZE - EFFECTS ON GENETIC-VARIATION OF POLLEN TRAITS

Various factors (pollen diameter, in vitro germination and tube length , in vivo growth rate in selfed and nonselfed styles) which could poss ibly contribute to the competitive ability of pollen were investigated on 30 Zea mays L. inbred lines. The only factor with which pollen dia meter was positively correlated was in vitro pollen-tube growth. Trait s related to the early stages of growth( in vitro germination, in vitr o tube length, early in vivo pollen growth rate) were all positively c orrelated with each other, and these early characteristics were negati vely correlated with late in vivo tube growth rate, which is largely i nfluenced by the stylar genotype.