Growth Analysis of Mayweed Chamomile (Anthemis cotula) Interference in Peas (Pisum sativum)

Abstract

Destructive growth analysis of field replacement series experiments with mayweed chamomile and dry field peas was used to determine the competitive relationship between the two species. Mayweed chamomile produced similar amounts of leaf area and dry weight per plant in a dry year and a wet year. On the other hand, dry field peas produced 20% more leaf area and 100% more dry weight per plant in the wet year compared to the dry year. Height, leaf area, and dry weight of peas reached maximum between bloom and pod-set, and then declined. Height and dry weight of mayweed chamomile increased steadily throughout the growing season. Mayweed chamomile leaf area reached a maximum at the beginning of flower stem elongation. Initially, the relative growth rate of mayweed chamomile was about three times greater than the rate for peas, but by 40 to 48 d after planting, rates were similar for both species. Relative yields and relative crowding coefficients for dry weight showed that peas were 3 to 20 times more aggressive than mayweed chamomile. Results of these experiments show that mayweed chamomile is a weak competitor against peas, but because it continues to grow after peas senesce, it could interfere with crop harvest.