Reproduction in plants may be affected by numerous factors including temperature, moisture, and nutrient availability. We tested the effects of nutrient supplementation on components of reproduction of the wildflower Clarkia unguiculata. Chamber grown plants were watered with either full strength commercial fertilizer (Peters - 20% Nitrogen, 20% Potassium, 20% Phosphorus) or with distilled water. Average plant height, pollen number, pollen grain size, style length, ovule number, pollen/ovule ratio, and pollen tube growth rate were determined for plants in each treatment. Plant height, pollen grain size, and style length were all significantly greater in unfertilized plants. Ovule number was significantly greater in fertilized plants. Fertilization treatment had no affect on pollen with respect to growth rate, however pollen from both treatments grew faster through styles of unfertilized plants. Our data suggest that nutrient supplementation may have significant effects on reproduction in the wildflower Clarkia unguiculata.

Key words: nutrient supplementation, ovule number, plant height, pollen number, pollen size, pollen tube growth