Seed germination and viability of herbicide resistant and susceptible Chenopodium album populations after ensiling, digestion by cattle and manure storage

Abstract

Chenopodium album became a problem weed in sugar beet production, due to resistance to metamitron, a key herbicide in this crop. Dispersal of the seeds from resistant biotypes may occur due to spread by wind, animals, agricultural machinery or manure. This study examined the effect of ensiling, digestion by cattle and storage in slurry and farmyard manure on the germination and viability of the seeds of one susceptible and three resistant C. album populations. After 4 weeks in a maize silo, seed viability of C. album populations was reduced drastically to 0-5%. Incubation for 24 h in the rumen followed by a post-ruminal digestion in vitro of intact seeds only resulted in a small reduction in viability in one C. album population. Storage in a slurry cellar for 16 weeks reduced the viability of intact seeds of the C. album populations to 25-60%. Only 0-1% of the seeds remained viable after storage in a farmyard manure heap for 4 weeks. An accelerated ageing experiment showed seed persistence to be population specific and less related to seed weight. Keeping a fresh maize silo closed for at least 4 weeks and heaping farmyard manure are excellent preventive measures to limit the spread of resistant C. album seeds between fields.

Weed seed survival in experimental mini-silos of corn and alfalfa

“…Higher dormancy could increase survival in silage since most weeds present nondeep physiological dormancy in which structures that protect the embryo play a role in preventing germination (Baskin and Baskin 1998). However, Aper et al (2014) have shown that the viability of seeds from both herbicide resistant and susceptible common lambsquarters does not exceed 5% after four months in corn silage.…”

“…Blackshaw and Rode (1991) demonstrated that a two month storage in barley (Hordeum vulgare L.) silage reduced weed seed viability substantially more than rumen digestion and that in fact adding rumen digestion to silage fermentation did not further reduce the viability of the 12 species tested except wild buckwheat (Polygonum convolvulus L.). Aper et al (2014) also demonstrated that a single month of storage in corn (Zea mays L.) drastically reduced the viability of common lambsquarters (Chenopodium album L.) seeds. Westerman et al (2012) demonstrated that weed seeds of twelve common species stored for 46 d in experimental jars filled with corn had a maximum of 1% viability, except velvetleaf (Abutilon theophrasti Medik) (32% viability).…”

“…Because silage crops are harvested earlier than grain crops of the same species, weeds have less time to produce and shatter seeds. Moreover, collected weed seeds will potentially be killed during silage fermentation and digestion by cattle (Blackshaw and Rode 1991;Aper et al 2014). Nevertheless, few studies have evaluated the survival of weed seeds in silage (Woodward 1940;Zahnley and Fitch 1941;Blackshaw and Rode 1991;Westerman et al 2012;Aper et al 2014).…”

Effect of herbicide resistance endowing three ACCase mutations on seed germination and viability in American slough grass ( Beckmannia syzigachne Steud. Fernald)

“…It is to be noted here that seeds containing 2027Cys/Cys ACCase showed an obvious higher vigor after 16 d in the incubator at 40 °C and 100% RH in accelerated ageing experiment, but no difference in P 50 compared with seeds containing wild-type ACCase. A previous study has also showed no difference in P 50 between three resistant and one susceptible Chenopodium album population, but resistant and susceptible C. album used in this study shared several different genetic backgrounds and evolutionary histories, and this may make the conclusion less accurate (Aper et al, 2014).…”

“…Where y is the viability of the seeds, x is the incubation time, C is the lower limit, D is the maximum germination (i.e. the initial viability) and b indicates the slope around P 50 (Seefeldt et al, 1995;Aper et al, 2014). Seed germination of six derived subpopulation was > 90% when incubation time was shorter than 4 d. Seed viability decreased strongly after 4 d in the incubator, and a very low germination was found after 16 d incubation (2.3% ~ 18.7%) (Figure 5).…”