Naslov
Efficacy of some herbicides for pre- and post- emergence weed control in soybean

Autori
Knežević, Mira ; Antunović, Manda ; Baličević, Renata ; Ranogajac, Ljubica

Izvornik
Herbologia - An International Juornal on Weed Research and Control (1840-0809) 10 (2009), 2; 65-74

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
soybean ; weed density ; alfa-metolachlor ; metribuzine ; clomazone ; (s) dimetenamid ; imazamox ; crop yield

Sažetak
Three-year field experiments were carried out on soybean in north-eastern Croatia from 2007 to 2009 to assess weed control efficacy for some herbicides and their effects on crop yields. The herbicides were used in pre- emergence and pre- plus post-emergence, single or split applications, at different rates and in different combinations. Main weeds were annual grass of Echinochloa crus-galli (13 - 75 shoots m-2), broad-leaved species of Ambrosia artemisiifolia (8 - 30 plants m-2) and Chenopodium album (3 - 19 plants m-2). Total weed density was higher in the wet season of 2008 by 173% and 89%, compared to the drier seasons of 2007 and 2009, respectively. Considering the pre-emergence application, herbicide combination with alfa-metolachlor (960 g a. i. ha-1) + metribuzine (350 g a. i. ha-1) + clomazone (168 g a. i. ha-1) gave 97% of total weed control in 2008 with adequate moisture before and after the application. In the unfavorable seasons of 2007 and 2009 the same treatment showed a lower but still good weed control (94%). Considering the pre-em. plus post-emergence herbicide applications, (s) dimetenamid (1008 g a. i. ha-1) plus imazamox, as a split (32 g + 16 g a. i. ha-1) provided the best control of main weeds (at least 90%) and consistently effective total weed control (94 - 98%) in all years. The same herbicide combination with a lower rate of (s) dimetenamid (720 g a. i. ha-1) plus imazamox (40 g a. i. ha-1), as a single application showed less A. artemisiifolia and C. album control in 2007 (up to 83%) and its affected crop yield. A similar efficacy was achieved with imazamox at same rate and mode of application when alfa metolachlor (960 g a. i. ha-1) + metribuzine (350 g a. i. ha-1) were applied pre-emergently (92%), with no damage to crop yield. Across-year differences in crop yield were insignificant between the pre-em. and pre-em. plus post-emergence herbicide treatments, ranging from 3189 kg to 3422 kg ha- 1.

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija)

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