Interactive effects of soil nutrients, moisture and sand burial on the development, physiology, biomass and fitness of Cakile edentula

The relative importance and interactive effects of nutrient supply, soil moisture content and sand burial on the development, physiology, biomass allocation and fitness of Cakile edentula were examined under controlled greenhouse conditions. Plant traits were more frequently affected by nutrient supply than by soil moisture content or sand burial. Measurements on most plant traits also varied depending on the two or three way interactions among the three environmental factors. Plants partially buried by sand had higher leaf chlorophyll concentration than those unburied at the early stages of development, especially under low soil moisture content. High nutrient supply tended to lower the leaf chlorophyll concentration of mature plants, and this effect was more pronounced under high as compared to low soil moisture content. High nutrient supply enhanced the photosynthetic capacity of plants when they were water stressed. With adequate soil moisture, high nutrient supply increased/decreased the photosynthetic capacity of plants with/without previous experience of water stress. High nutrient supply increased the biomass allocation to the root system of plants, especially at low soil moisture content. Partial sand burial also promoted biomass allocation to the root system of plants grown at low soil moisture content. (C) 1996 Annals of Botany Company