Iranian Society of Weed Science Iranian Journal of Weed Science 1735-3548 9 1 2013 08 23 Predicting Seedling Emergence of Hordeum spontanum: Do the Emerged Ecotypes from Different Climates in Iran Indicate Different Patterns of Emergence? Predicting Seedling Emergence of Hordeum spontanum: Do the Emerged Ecotypes from Different Climates in Iran Indicate Different Patterns of Emergence? 15 26 4093 FA Hassan Pourali Moghanloo Hassan Alizadeh Mostafa Ovisi Journal Article 2013 12 18 Knowledge about weed seedling emergence pattern provides helpful information to improve management decision making. Emergence pattern is genetically controlled and built up in association with environmental conditions. Six <em>Hordeum spontaneum</em> Koch populations that collected from different climates around Iran, were sown in field in a complete randomized block design with 4 replications. Seedlings were counted using the fixed quadrates at 3-day intervals until no emergence occurred in field. Cumulative emergence against thermal time (GDD) was described with sigmoid function for each population. Parameter estimates indicated appearance of populations in field with different patterns. Kermanshah population was the first seedlings emerged receiving 67 GDD followed by Khorasan Razavi populations which emerged 2-weeks later (76.6 GDD). Tehran and Ghazvin populations showing similar pattern appeared in field at GDD of 76.6. Fars and Khozestan were the last populations emerged in field with receiving 83 and 88 GDD, respectively. There are significant correlations between emergence patterns and climate conditions form which the populations were collected. Knowledge about weed seedling emergence pattern provides helpful information to improve management decision making. Emergence pattern is genetically controlled and built up in association with environmental conditions. Six <em>Hordeum spontaneum</em> Koch populations that collected from different climates around Iran, were sown in field in a complete randomized block design with 4 replications. Seedlings were counted using the fixed quadrates at 3-day intervals until no emergence occurred in field. Cumulative emergence against thermal time (GDD) was described with sigmoid function for each population. Parameter estimates indicated appearance of populations in field with different patterns. Kermanshah population was the first seedlings emerged receiving 67 GDD followed by Khorasan Razavi populations which emerged 2-weeks later (76.6 GDD). Tehran and Ghazvin populations showing similar pattern appeared in field at GDD of 76.6. Fars and Khozestan were the last populations emerged in field with receiving 83 and 88 GDD, respectively. There are significant correlations between emergence patterns and climate conditions form which the populations were collected. https://ijws.areeo.ac.ir/article_4093_49fa3569f8761ffd4495018e1727f4e7.pdf