GROZI DELCHEV1 and TEODORA BARAKOVA2
1 Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
2 Field Crops Institute, 6200, Chirpan, Bulgaria
DELCHEV, G., and T. BARAKOVA, 2018. Efficacy of herbicides and herbicide combinations at sorghum (Sorghum bicolor Moench.). Bulg. J. Agric. Sci., 24 (Suppl. 1): 33–39
In the period 2012-2014 a field experiment was carried out with sorghum hybrid Arcansiel (Sorghum bicolor Moench.). A total of 4 soil-applied herbicides were tested - Tender EC (S-metholachlor), Silba SC (S-metholachlor + terbuthylazine), Sharpen 33 EC (pendimethalin) and Wing P (dimethenamid + pendimethalin) and 4 vegetation-applied herbicides - Casper 55 WG (prosulfuron + dicamba), Cambio SL (bentazone + dicamba), Camix 560 SE (S-metholachlor + mesotrione) and Maton 600 EK (2.4-D ester). In all variants seeds were treated with the herbicide antidote Concep III (fluxofenin) to protect sorghum from the phytotoxic effect of antigraminaceous herbicides. Soil-applied herbicides Tender, Silba, Sharpen and Wing have high efficacy against annual weeds in grain sorghum grown by Concep technology. Vegetation-applied herbicides Casper, Cambio and Maton have very high efficacy against all broadleaved weeds. Herbicide Camix is the only vegetation-applied herbicide, which can control secondary weeding of annual graminaceous weeds in sorghum which seeds are treated with herbicide antidote Concep III. The combinations between soil-applied and vegetation-applied herbicides control successfully all groups of weeds with the exception of perennial graminaceous weeds from rhizomes. Herbicide Camix causes poor phytotoxicity in sorghum plants. Use of herbicide combinations Silba + Casper and Wing + Cambio result in obtaining high grain yields of sorghum. High grain yields are also obtained through the use of herbicide combinations Silba + Cambio, Sharpen + Cambio, Tender + Casper and Wing + Casper. Combining Camix and Maton with soil-applied herbicides leads to lower grain yields.