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The purpose of this study is to determine the allelopathic effects of extracts obtained by using liquid nitrogen from the plant of Antep radish (Raphanus sativus L.) and little radish (Raphanus sativus L. var. radikula) on germina-the most significant effects were observed in the results of Antep radish root experiments. In this experiment group, the inhibition rate of root and stem length of weed seeds at a concentration of 16% were 86% and 82%, respectively, when compared to the control. In addition, the germination number was reduced by 74.36% in the seeds at the highest concentration compared to the control. As a result of the study, it was determined that samples of radish plant crushed with liquid nitrogen were stored for a long time and showed high allelopathic effect on sterile wild oats plant.

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The response of winter barley to drift doses of imazamoxResponse of the winter barley (Hordeum vulgare L. var. Aydan Hanım) to imazamox drift rates was determined in trial experiments conducted Ankara province (Gölbaşı, Halaçlı village) in 2014 and 2016. The herbicide at the doses of 0.625, 0.315 and 0.08 g active ingredient (a.i.) da -1 was applied to winter barley plants during the first node stage using a CO2 pressurised knapsack sprayer. The field trials were set randomised block design with 4 repetitions. Phytotoxicity and yield loss caused by the lowest rate of herbicide was very limited while the yield loss caused by the high doses were very high. Parcel yields used at the highest herbicide dose (0.625 g a.i. da -1 ) was reduced by 55% compared to the untreated control in 2016 when precipitation was higher than normal. There was a closely relation between efficacy of the drift doses of herbicide and weather conditions. High amount of precipitation during the active growth stage can increase the detrimental effects of the herbicide. Keywords

Introduction Sunflower (Helianthus annuus L.) is a valuable oilseed crop cultivated in North America, Europe, and Asia for more than 100 years. The crop is mainly grown for seed oil and animal feed (Kaya et al., 2012), but other uses include ornamental, medicinal, and biodiesel purposes in some countries such as Pakistan, USA, and Serbia (Arshad and Amjad, 2012; Burnett, 2017; Đurišić-Mladenović et al., 2018). Most of the world's sunflower seed production occurs in Asian and European countries where the agroecological conditions are favorable for sunflower growth and development (Kaya et al., 2008). Ukraine and Russia lead the world in terms of sunflower seed export, while Turkey is the leading importer of the seed in spite of growing it in large quantities (http://www.sunflowernsa. com/stats/world-supply/ [accessed on 17 April 2013]). Different pests and abiotic factors can adversely affect sunflower seed yield throughout the growing season. Among the biological yield-limiting factors, weeds are particularly important because they compete with sunflower plants for space, light, nutrients, and water (Sedghi et al., 2008). Significant yield losses due to broadleaf weeds such as kochia (Kochia scoparia L.), wild mustard (Sinapis arvensis L.), field bindweed (Convolvulus arvensis L.), and common cocklebur (Xanthium strumarium L.); grasses such as large crabgrass (Digitaria sanguinalis (L.) Scop.) and johnsongrass (Sorghum halepense (L.) Pers.); and parasitic plants, including broomrape (Orobanche spp.), have been reported (Çoruh and Zengin, 2009; Olson et al., 2011; Başaran et al., 2017). Although nonchemical weed control practices like mechanical methods or herbicide combined with them have been employed in conventional crop production systems, (CSPS) such as maize, sunflower, and soybean (Pannacci and Tei, 2014), chemical weed control practices have commonly been preferred during the last half century (Kraehmer et al., 2014). In some crops, such as wheat (Triticum aestivum L.), numerous herbicides belonging to different chemical