Evaluation of Morpho-physiological Responses of Iranian Rice Landraces and Improved Genotypes to Iron Deficiency in Nutrient Solution

Excessive application of P fertilizers, use of the bicarbonated water sources for irrigation concomitant to a low level of organic matter have resulted in widespread iron deficiencies in crop plants in Iran. One of the strategies to overcome this problem is to select tolerant genotypes to iron deficiency (i.e. iron-use-efficient genotypes) or bred genotypes with high-micronutrient-uptake ability. Therefore, this experiment was conducted to study the behavior of twelve Iranian rice landraces and improved genotypes to iron deficiency (Tarom Mahalli, Amol 2, Musa-Tarom, Gharib, Shiroudi, Bejar, Neda, Nogouran, Jozdan, Sazandegi, Zayande Roud, and Kouhrang) as exposed to two levels of chelated iron fertilizers, including 5mM (iron deficiency) and 50mM (no iron deficiency) in Yushida nutrient solution culture. A factorial experiment based on a completely randomized design with four replicates was carried out in Soilless Culture Center at Isfahan University of Technology, Isfahan, Iran in 2013. The results showed that the iron content, shoot and root dry weights, total dry weight, leaf area, root length and volume and the number of tillers were significantly affected by genotypes, iron fertilizer, and their interaction. The mean dry weights were 0.215, 0.138, and 0.255 g per plant in northern landraces, northern improved, and central Iranian genotypes under no iron deficiency condition, but they were decreased by 25.7, 35.2, and 23.0% under iron deficiency condition, respectively. Based on the magnitude of decrease of total biomass under iron deficiency condition, genotypes such as Musa-Tarom, Bejar, and Zayande Roud seemed to be more tolerant in comparison to Jozdan, Amol 2, and Shiroudi.