Iron Nutrition <i>vis-à-vis</i> Aconitase Activity and Ferritin Accumulation in Tropical <i>Indica</i> Rice Cultivars Differing in Grain Iron Concentration

Abstract

Effect of Fe nutrition on Fe acquisition, aconitase enzyme activity and assimilation of the element in ferritin protein was studied in two indica rice cultivars viz. Sharbati and Lalat having contrasting grain Fe concentration. Young rice seedlings were grown in hydroponics with different levels of Fe. For comparison, the two cultivars were also grown in the field under natural conditions of rice culture. Iron accumulation, aconitase activity and ferritin level were higher in the high Fe containing cultivar, Sharbati than that in the low Fe containing cultivar, Lalat. While aconitase activity increased consistently with the increase in concentration of Fe in the growing medium, the same was not found to be true for accumulation of ferritin protein. The leaf ferritin level increased up to a certain level of Fe in the growing medium and declined thereafter. Levels of Fe in the growing medium giving maximum ferritin synthesis were found to be different in the two rice cultivars. In both cultivars, aconitase activity attained maximum level after 20 days of panicle emergence (heading). Pattern of Fe accumulation in the leaves in response to increasing Fe level in the nutrient solution paralleled with that of the aconitase activity indicating a positive correlation. It was concluded that accumulation of both ferritin protein and aconitase enzyme were influenced not only by the Fe level in the growing medium but also by the internal Fe concentration of the two cultivars.

Effect of different amendments on rice (Oryza sativa L.) growth, yield, nutrient uptake and grain quality in Ni-contaminated soil

“…This decreased Ni bioavailability in soil solution has led to enhanced uptake of Fe by rice plant and later its accumulation in grains. Our findings are in line with Panda et al (2014) who found that application of Fe supplementation in the growing medium increased Fe accumulation, which in turn increased aconitase activity, and ferritin accumulation in the seedlings of two rice cultivars.…”

Dealing with iron metabolism in rice: from breeding for stress tolerance to biofortification

“…When both susceptible and tolerant cultivars, BR-IRGA 409 and EPAGRI 108 respectively, were subjected to high concentrations of Fe there was less accumulation of this element and greater accumulation of ferritin in the tolerant cultivar, suggesting that this protein may be involved in this mechanism of tolerance ( Silveira et al ., 2009 ). However, a study by Panda et al . (2014) found that when there is Fe accumulation, the activity of aconitase and ferritin levels are higher in a cultivar that accumulates higher concentrations of Fe compared to the cultivar that has a lower concentration of this element.…”

Isolation and selection of siderophore-producing bacteria from roots of Simadu pineapple (Ananas comosus) in Subang District, West Java

“…Aconitase (ACO) requires many Fe-S groups because Fe-S is unstable in ACO, so it must be replaced many times by other Fe-S groups. The result of isocitrate changes in the Krebs cycle is alpha-ketoglutarate which after being reacted with the amino acid glutamate (glutamic dehydrogenase or oxaloacetate-glutamate transaminase) will become glutamic acid which is the raw material for making chlorophyll (Lushchak et al, 2014;Panda et al, 2014;Rout & Sahoo, 2015).…”