Weed seed production and seedling emergence responses to late-season glyphosate applications

Abstract

Seed production and seedling emergence of three broadleaf weed species were evaluated following glyphosate application at initial seed set, mid seed fill, and physiological maturity. In greenhouse experiments averaged across glyphosate rates of 0.42, 0.63, and 0.84 kg ae ha−1, Xanthium strumarium 100-bur weight and burs per plant were reduced at least 69 and 70%, respectively, for application at initial fruit set compared with later applications, and seedling emergence was 3% of the nontreated check. Glyphosate application at initial seed set reduced Sesbania exaltata 100-seed weight 73%, seed per plant 86%, and seedling emergence 94%. Senna obtusifolia 100-seed weight, seed per plant, and seedling emergence were reduced 46, 83, and 66%, respectively, when glyphosate was applied at initial seed set. In field experiments, X. strumarium and S. exaltata seed production were reduced only when glyphosate was applied at initial seed set. Compared with the nontreated check, seedling emergence following initial seed set application was reduced 82% for X. strumarium and 94% for S. exaltata. S. obtusifolia response in the field was inconsistent with no reductions in seed per plant or seedling emergence observed the first year. The second year, initial seed set application reduced seed per plant 88% and seedling emergence 72%.

Weed management options in transgenic stacked and non transgenic maize (Zea mays) hybrids-A review

“…Effect of POE glyphosate on soil weed seed bank: Application of glyphosate was done during reproductive stage of soybean can be beneficial to producers by reducing weed seed impact (Clay and Griffin, 2000). Seed bank with little modification to their production practices, reducing future weed interference and providing greater flexibility in weed management decisions.…”

Evaluación de la toxicidad del Roundup en la germinación de semillas de maíz (Zea mays)

“…Se ha demostrado que el glifosato causa diferentes efectos sobre hierbas y semillas (Clay & Griffin, 2000;Bennet & Shaw, 2000;Gressel, 2010). Sin embargo, estos resultados son controvertidos, por la existencia de diferentes estudios que afirman lo contrario, argumentando que el glifosato no genera efectos significativos en el desarrollo o rendimientos de las plantas (Blackburn & Boutin, 2003;Neve, Sadler, & Powles, 2004;Glaspie et al, 2011 …”

Essai n° 208: Essai sur plante terrestre : essai d'émergence de plantules et de croissance de plantules

“…10 -20 (6,9) tremper les graines humides dans l'eau pendant 24 heures (9) scarification (14) la viabilité des graines dépend de leur couleur (1) aucun traitement particulier (6) POST (6, 9) A…”

“…A sol alluvial (16) 11 -13 (9,14) L > D (9) 10 -20 (9,21) tremper les graines dans l'eau pendant 24 heures (9) (5) POST (5) A, E, F POST ( L > D (10) 20 (10) 10 (62 %) (10) germination inhibée par l'obscurité (1,(17)(18)(19) aucun traitement particulier (10) POST (10) A, E 0 mm indique que les graines sont semées sur la surface du sol ou que les graines ont besoin de lumière pour germer. 4 Les nombres indiqués correspondent au nombre de jours pendant lesquels germe un certain pourcentage de graines selon la référence indiquée, par exemple, germination 3 jours (50 %) (référence 19).…”