Document Type : Research Paper
Authors
1 Department of Plant Science and Medicinal Herbs, Meshgin-Shahr Faculty of Agriculture- University of Mohaghegh Ardabili, Ardabil, Iran
2 Ardabil Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Ardabil, Iran.
Abstract
Objective: This research was carried out to study the potential of photoassimilates accumulation and remobilization in the stem internodes of rainfed barley cultivars grown under regions with different climates.
Methods: Eight barley cultivars (four two-rowed and four six-rowed cultivars) were cultivated under rainfed conditions in Meshginshahr (Mediterranean region with cold winter) and Jafarabad-Moghan (semi-tropical region with semi-cold winter) during 2023-2024 growing season. Photoasimilate accumulation and remobilization were measured in the stem internodes (peduncle, penultimate, and lower internodes) based on dry weight changes.
Results: Experimental sites were different in terms of climate. At Meshginshahr site, the high amount of precipitation and the low average temperature caused the growing season to be longer compared to Moghan site. The length of upper internodes (peduncle and penultimate) was higher in Meshginshahr than Moghan. On the other hand, the lower internodes formed a higher proportion of the stem length at Moghan region. The maximum weight of peduncle, penultimate and lower internodes was attained in Meshginshahr condition at 18, 18 and 15 days after anthesis, and in Moghan region at 4, 4 and 4 days after anthesis, respectively. The maximum weight of internodes (accumulated photoassimilates), the amount of reserves remobilization as well as the amount of grain yield per stem were higher in Meshginshahr than Moghan. Large variations were found for morphologic, physiologic, and agronomic traits among tested cultivars. In general, cultivar × location interaction was not significant for maximum weight and maximum specific weight of internodes and stem. Althought the values of these traits varied with location, the rank of cultivars for these variables remaned nealy unchanged. The highest values of internode’s weight and specific weight belonged to Barzin and Jolgeh cultivars at Meshginshhar and Moghan regions. Cultivar × location interaction was significant for internodes and stem’s remobilization. The change of location, on the one hand, altered the values of these traits and, on the other hand, changed the ranking of cultivars for them. Jolgeh and Barzin at Meshginshahr and Barzin and Oxin at Moghan region showed the highest values of internode’s cumulative remobilization.
Conclusion: In the current study, the amount of accumulation and remobilization was highest in the lower internodes under both Meshginshar and Moghan regions. Therefore, in order to reach their potential for accumulating the dry matter at the beginning of spring as well as to be a major source of dry matter remobilization at the end of growing season, the lower internodes are expected to have appropriate lengths, weights and specific weights.
Keywords
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