Seed bank modelling of volunteer oil seed rape: from seeds fate in the soil to seedling emergence

Abstract

-Studies were conducted to estimate parameters and relationships associated with sub-processes in soil seed banks of oilseed rape in Gorgan, Iran. After one month of burial, seed viability decreased to 39%, with a slope of 2.03% per day, and subsequently decreased with a lower slope of 0.01 until 365 days following burial in the soil. Germinability remained at its highest value in autumn and winter and decreased from spring to the last month of summer. Non-dormant seeds of volunteer oilseed rape did not germinate at temperatures lower than 3.

A review of the relationship between primary and secondary dormancy, with reference to the volunteer crop weed oilseed rape (Brassica napus)

“…Soltani et al . () found such a dormancy cycle for buried seeds of B. napus at the germination test temperature of 20°C in the dark. Germinability of exhumed seeds was low (11–44%) from spring to late summer and high (68–100%) from autumn to spring.…”

“…Freshly matured seeds of B. napus can germinate to high percentages at certain test temperatures in both light and dark (López‐Granados & Lutman, ; Schatzki et al ., ; Soltani et al ., , ; Haile & Shirtliffe, ; Née et al ., ; Huang et al ., ). Table includes studies in which primary dormancy in B. napus was determined.…”

“…Soltani et al . () tested freshly matured seeds of B. napus in which 94% of viable seeds germinated; thus, 6% of the seeds exhibited primary dormancy at the single test temperature of 20°C in dark. In that study, germinability of freshly matured seeds had increased by 0.02% day −1 during storage (20°C and dark), presumably due to after‐ripening.…”

“…However, whether primary dormancy is a requirement for a seed to have the capacity to become secondarily dormant is unclear. There are many reports that seeds of B. napus have little or no dormancy and that water stress and darkness make them light‐requiring, that is induce them into secondary dormancy (Schlink, ; Pekrun et al ., ,b; Lutman et al ., ; Weber et al ., ; Soltani et al ., , ). However, the capacity for induction of nondormant seeds into secondary dormancy is contrary to what has been shown for some other species (Symons et al ., ; Girard, ; Simpson, ; Auge et al ., ; Coughlan et al ., ; Edwards et al ., ).…”

Quantitative and qualitative analyses of weed seed banks of different agroecosystems

“…In agroecosystems the weed population is related to their seed bank, so that the knowledge of the seed bank size and of its species composition can be used to predict future infestations, to construct population models along time, and consequently for the definition of management programs that lead to a better rationalization of the use of herbicides (Gardarin et al, 2011;Soltani et al, 2013). In general, the decision-making of weed management strategies is based on visual evaluations of the needed weed control intensity without much technical criteria.…”