Response of Sorghum halepense L. (Pers.) Populations to Nicosulfuron, Rimsulfuron and Prosulfuron+Primsulfuron-methyl

Abstract

The effects of herbicides nicosulfuron, rimsulfuron and prosulfuron+primsulfuronmethyl on eight populations of Sorghum halepense L. (Pers.) under controlled conditions were investigated. The herbicides were applied at different rates (0x; 0,5x; 1x; 1,5x; 2x; 3x recommended application rate for field use) when plants reached the height of 20-25 cm. The parameters measured seven days after treatment were leaf surface and fresh and dry mass of plants; the obtained results were then used for ED50 calculations. The response of Sorghum halepense populations to nicosulfuron, rimsulfuron and prosulfuron+primsulfuron-methyl varied from population to population, and depending on the applied rate and the measured parameter. Resistance development was not observed in any of the populations that survived herbicide treatment before seed collecting. Only the population P2 showed somewhat decreased susceptibility to nicosulfuron, which can be regarded as an early stage of resistance development.

Ispitivane su reakcije 8 populacija vrste Sorghum halepense L. (Pers.) na herbicide nikosulfuron, rimsulfuron i prosulfuron+primisulfuron-metil u kontrolisanim uslovima. Primena različitih količina (0x; 0,5x; 1x; 1,5x; 2x; 3x od količine koja je preporučena za primenu u poljskim uslovima) ovih herbicida izvedena je kada su biljke bile visine 20-25 cm. Sedam dana nakon primene herbicida mereni su sledeći parametri: površina listova, sveža i suva masa biljaka, a na osnovu dobijenih rezultata su određene ED50 vrednosti. Reakcije populacija S. halepense na nikosulfuron, rimsulfuron i prosulfuron+primisulfuronmetil su bile različite u zavisnosti od populacije, količine primene herbicida i ispitivanog parametra. Nijedna od populacija koja je pre sakupljanja semena preživela primenu navedenih herbicida nije razvila rezistentnost. Samo je kod populacije P2 potvrđena smanjena osetljivost na nikosulfuron, koja se može smatrati početkom razvoja rezistentnosti.