Resistance of Benghal Dayflower (Commelina benghalensis) Seeds to Harsh Environments and the Implications for Dispersal by Mourning Doves (Zenaida macroura) in Georgia, U.S.A

Abstract

The potential dispersal of Benghal dayflower seeds by mourning doves was studied in southern Georgia, U.S.A. The gut contents (both crop and gizzard) of mourning doves harvested in the autumn months were investigated to determine if mourning doves fed on Benghal dayflower and whether seeds can survive conditions in the bird gut. Research indicated that mourning doves fed selectively on Benghal dayflower with some harvested birds containing hundreds of Benghal dayflower seeds and capsules in their guts. Further, some seeds recovered remained highly viable. Germination rates in seeds taken from bird crops were similar to controls over the first 4 wk of germination and enhanced over control treatments during the latter 16 wk of a 20-wk germination study. Ultimately, seeds extracted from dove crops had 92% germination as compared to 80% for control seeds. Seeds extracted from dove gizzards had 45% germination, about half that of controls. Benghal dayflower seeds have a structurally reinforced seed coat that probably aids in survival of mechanical damage through bird intestinal tracts. Benghal dayflower seeds exposed to 1.0 M HCl treatment for 2 h had little loss in viability, successfully germinating after such treatment. When evaluating mechanisms for the eradication of Benghal dayflower from agricultural crops, consideration needs to be given to the large number of mourning doves and other bird species that visit cropland and potentially aid in its dispersal.

Methods to Break Seed Dormancy of Rhynchosia capitata, a Summer Annual Weed

“…Total germination of the HCl-treated seeds increased when compared to the control over an extended period (up to 18 h) indicating a slow release from seed dormancy. These results are in line with Goddard et al (2009) who found that Benghal dayflower seeds exposed to HCl soaking treatments successfully germinated with little loss of viability after each treatment. Seeds from the 18-h treatment were extremely soft and moldy at the end of the germination test, so lower germination was recorded in this treatment.…”

“…This kind of dormancy could be overcome by weakening the tegument by allowing water to pass and initiate germination (Cavalheiro et al, 2007). This process can also occur through the action of acids during seed digestion by dispersing animals (Goddard et al, 2009).…”

Reducing the Risks of Herbicide Resistance: Best Management Practices and Recommendations

“…For instance, it has been suspected that cross-state transportation of cattle has greatly contributed to the spread of tropical soda apple (Solanum viarum Dunal), a federally listed noxious weed capable of remaining viable in the rumen of cattle (Byrd et al 2004). Weed seed dispersal by wildlife, such as deer, birds, and rodents, is also possible (Goddard et al 2009;Traveset et al 2001).…”

Assessment of an Invasive Weed “Maimaio” Commelina foecunda in the Sesame Fields of Western Zone of Tigray, Northern Ethiopia

“…And germination percentage and population stand of C. foecunda were very high at lower soil depth (<5 cm) [15]. Goddard et al [17] reported that large number of mourning doves and other bird species that visit cropland help in dispersal and expansion of C. benghalensis.…”