The effects of substrate moisture content on water potential, gas exchange rates, growth, and yield in strawberry plants grown under greenhouse conditions.

摘要

A greenhouse study was conducted to determine the effects of different levels of moisture content in the growth substrate on water potential, gas exchange rates, growth and yield in strawberry plants. Strawberry (cv. Elkat) plants were grown in containers filled with substrate consisting of sandy loam and perlite, and stacked in columns (each consisting of three sections). The bottom section was partially submerged in a container filled with water. Water flowed to the upper sections of the column by capillary action. The moisture content of the substrate was not uniformly distributed in the column. The moisture content of the substrate was ~34% v/v in the bottom section, ~25% v/v in the middle section, and ~14% v/v in the top section of the column. Leaf fresh weight, leaf surface area, and yield were highest in plants growing in the bottom and middle sections of the column, and lowest in plants growing in the top section of the column. However, there were no significant differences in root fresh weight and total root length between plants from different sections of the column. Water potential and gas exchange rates were measured to assess the physiological state of the plants. Water potential in the leaves decreased when the availability of water was limited. This was especially true for the plants growing in the top section of the column. Photosynthetic rates and transpiration rates were also lowest in the plants growing in the top section of the column.