Demography of Corn Poppy (Papaver rhoeas) in Relation to Emergence Time and Crop Competition

Abstract

Twenty-day cohorts of corn poppy were grown in the presence or absence of barley, and seedling survival, biomass accumulation and allocation, plant reproduction, and seed dormancy were measured. Seedling survivorship and biomass accumulation differed strongly among cohorts and were influenced by crop competition. In the absence of crop competition, plants from the first three cohorts (emerging October to January) had 900% higher biomass and 160% more seeds per plant than later cohorts (emerging January to April). Crop competition reduced cohort fitness; for example, in 2003 to 2004, corn poppy biomass was reduced 57 to 96%, and seed production 77 to 97%. Seeds collected from plants that had emerged in spring were less dormant, and thus, germination and emergence of these seeds were higher (25% higher and 200 to 600% higher, respectively) than those for seeds collected from other cohorts. Environmental factors at the time of seed formation may be responsible for the observed differences in dormancy. Cohort-dependent emergence, growth, reproduction, and dormancy have relevant implications for corn poppy management and demography in agricultural systems in northeastern Spain. The dormant seeds produced by autumn to winter cohorts will be the main contributors to the seed bank and weed population shift in subsequent generations. For efficient corn poppy management, the control of cohorts emerging before or with the crop in a cereal field is essential.

Seed Biology of Lepidium apetalum (Brassicaceae), with Particular Reference to Dormancy and Mucilage Development

“…However, we never observed any seedlings of L. apetalum in the summer, perhaps since environmental conditions are unfavorable for germination. Other weed species that germinate mainly in autumn in nature also showed highest germination percentages at the 10/20 • C temperature regime [33,34]. Seed dormancy status is associated with seasonal temperature changes [2,5,32].…”

Integrated effect of crop sowing date and herbicide stress on fitness of Bromus diandrus Roth

“…The stability of the number of caryopses per spikelet between ETs in the first season demonstrates that it was not affected by plant competition whereas the variation of these values in 2009/10 and 2010/11 were caused by herbicide effect. Similarly, Torra & Recasens (2008) observed stable values of the number of seeds per capsule in corn poppy (Papaver rhoeas) despite the decreasing performance and reproductive fitness in function of cohort emergence and crop competition. These results suggest that despite the changes in fitness characteristics according to competition, the plant keeps a regulation mechanism that guarantees a minimal fecundity.…”

PIM (Poppy Integrated Management): a bio‐economic decision support model for the management of Papaver rhoeas in rain‐fed cropping systems

“…This version also accounts for cohort emergence on seed production. Seed production in P. rhoeas is highest in those plants emerging first and decreases gradually in later‐emerging plants (Torra & Recasens, 2008). In the PIM model, weed seed production by cohorts is represented by seed production indices.…”