Common Cocklebur (<i>Xanthium strumarium</i>) Response to Nicosulfuron

Abstract

The response of two populations (CC1, 43.59°N &amp; 20.40°E; CC2, 44.46°N &amp; 20.17°E) of common cocklebur (Xanthium strumarium L.) to nicosulfuron was investigated both in field experiments and in the laboratory. Population CC1 had no history of treatment with any herbicide, while population CC2 was treated with ALS inhibitor herbicides for six consecutive years. In the field, plants were treated post-emergence with nicosulfuron (0, 10, 20, 40, 60 and 80 g ai ha-1) at four true leaves. Visual injury estimation and vegetative parameters (plant height, fresh weight, leaf area) were recorded about month after herbicide application. The acetolactate synthase (ALS) enzyme activity in response to herbicide concentrations of 0, 0.01, 0.1, 1, 10, 100 μM was determined in vitro. GR50 values for vegetative parameters and I50 values for ALS activity were slightly greater for the CC2 than for the CC1population, but the results confirmed that neither population was susceptible to nicosulfuron. Namely, based on results for fresh weight, the population CC1 was about 3.9 and 2.6-fold more susceptible to nicosulfuron than population CC2 in two consecutive years, but differences were not so prominent for other parameters (plant height, leaf area and ALS activity), ranging from 1.18 to 1.8-fold. The differences between population CC1 and CC2 could be attributed to inter-population variability in susceptibility to nicosulfuron or could be the consequence of repeated application of ALS herbicides to the CC2 population during the six previous years. Future investigations are necessary in order to clarify this dilemma.

Effects of nicosulfuron on biological production of weedy sunflower (Helianthus annuus)

“…Namely, the period between sowing and sampling dates in 2008 was characterized by somewhat higher rainfall than the corresponding period of 2009. This is coinciding with previous studies which confirmed that environmental conditions significantly affected the activity and effects of post-emergence herbicides (Bozic et al, 2012(Bozic et al, , 2015bBožić et al, 2019). In conclusion, nicosulfuron was found to have a significant impact on weedy sunflower vegetative production (plant height, fresh weight and leaf area) and on some generative parameters (number of heads per plant, weight of seeds per plant and number of seeds per plant).…”

Fatty Acid Composition of Seed Oil from Cocklebur (Xantium Strumarium Subsp. Strumarium) Grown in Turkey

“…Xanthium L. species are annual and seen as it has no commercial properties. Therefore, it is diagnosed as a weed and while farmers are trying to get rid of cocklebur due to its detrimental effect on crops, at the same time, farmers waste not only their strength but also their time and money [9].…”

Weed Resistance to Herbicides

“…In Serbia, study of weed resistance to herbicides started in the 1990s with resistance of Amaranthus retroflexus and Chenopodium hybridum to PS II inhibitors (atrazine) [8][9][10]. Until today, in Serbia, as a small county with less than 3 million ha arable lands, in the last 15 years, eight herbicideresistant weed species were confirmed: A. retroflexus, Setaria viridis, C. hybridum and Abutilon theophrasti to PS II inhibitors, as well as A. retroflexus, E. crus-galli, Datura stramonium, Chenopodium Herbicide Resistance in Weeds and Crops album and Sorghum halepense to ALS inhibitors [11][12][13][14][15][16][17][18][19]. According to the herbicide resistance mechanisms, all processes can be grouped as follows: target-site resistance, non-target-site resistance, cross-resistance and multiple-resistance [20][21][22].…”