| Summary: | Leaf rust is responsible for most economically important wheat disease with yield losses. Growers usually use fungicides once or twice a year to control wheat leaf rust in Iran (Khuzestan Province). The purpose of the present study was to determine profit obtained from using propiconazole in five local winter wheat cultivars with different resistance level, including Chamran 2, Star, Ofogh, Kavir, and Boolani against wheat leaf rust in 2015–16 and 2016–17. The experiment was performed in five treatments. The first was the application of fungicide as soon as the symptoms were observed. In the second, third, and fourth treatments the fungicide application was after one, two, and three weeks of the symptom appearance, respectively. In the fifth one, there was no spraying and disease was left to develop to its final severity. The price of the fungicide and spraying cost were obtained by evaluations via three representatives of pesticides sale. In the 2015–16 growing year the net return in cv. Chamran 2 in the first treatment (growth stage GS 53) was $236 ha−1. In Star and Ofogh, except for treatment 1 and 2, a significant difference was observed for all treatments (P < 0.05) and the net return were $193–$619 ha−1 and $82–$311 ha−1, respectively. In Boolani and Kavir cultivars depending on the treatments, $291–$948 h−1 and $328–$829 ha−1 were obtained, respectively. In 2016–17 growing year in cv. Chamran 2 the net return amounted to $153–$226 ha−1. The net returns in different treatments of the Star and Ofogh cultivars were $228–$568 ha−1 and $-2–$342 ha−1, respectively. The net returns in Boolani and Kavir cultivars were high and reached to $700 ha−1. Depending on the resistance of cultivars, for each one $ cost for using fungicides, $12–$59 ha−1 profit was gained. There was a higher yield increase in 2016–17 than 2015–16; however, due to low wheat price ($0.36 per kg in 2016 and $0.32 per kg in 2017), the net return in 2017 was less than 2016. Results showed that the best times to control of wheat leaf rust are growth stages GS41- GS60. Keywords: Propiconazole, Leaf rust, Net returns, Winter wheat, Fungicides
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