A Physiological Analysis of Genetic Variation in Relative Growth Rate within Plantago major L.

Publisher Website
Google Scholar
Abstract
Genetic variation in relative growth rate (RGR) was studied in Plantago major L. Inbred lines of subspecies major had on average a 14% lower RGR than ssp. pleiosperma lines. A detailed growth analysis was done with two inbred lines. W9 (ssp. major) had a 20% lower RGR than A4 (ssp. pleiosperma). The higher RGR of A4 was associated with an 11% lower net assimilation rate. Photosynthesis and shoot dark respiration per leaf area was 23% and 30% lower in A4. The root respiration rate per gram dry weight was 20% higher in the fast growing line. A 30% higher specific leaf area (SLA) was associated with the higher RGR, while leaf thickness was the same. The leaf weight ratio was slightly higher in A4 and thus also contributed to its higher RGR. The high SLA of A4 was associated with a low ratio between dry weight and fresh weight of leaves and roots. The epidermal (adaxial) cell number per leaf area was 27% lower in A4. We conclude that the lower RGR of W9 is due to a changed allocation pattern, which was only partially compensated for by its higher photosynthetic rate.

This publication has 0 references indexed in Scilit: