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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 8/29/2013 Publication Date: 4/15/2015 Citation: Bellaloui, N., Reddy, K.N., Mengistu, A. 2015. Drought and heat stress effects on soybean fatty acid composition and oil stability. Book Chapter. 45:377-380. Interpretive Summary: Previous research showed that soybean oil content and composition (the distribution of individual fatty acids in the oil) change with cultivar, environment (mainly heat and drought), and geographical location. The changes in fatty acid composition under these conditions affect fatty acid stability (oil shelf live and oil processing), creating a challenge for the industry to predict production and oil quality under different environmental conditions. Therefore, the stability of oil and fatty acid has become a subject of intensive research and a major goal of soybean breeding programs. Lower palmitic and stearic fatty acids and higher oleic, linoleic, and linolenic fatty acid contents are desirable for human health. However, higher oleic acid and lower linoleic and lower linolenic fatty acids are desirable for oil stability and processing. Plant breeding and gene modification strategies are currently being used by seed companies to design the composition of fatty acids in seed oil for health benefits and increased shelf life after processing. The effects of two major environmental factors (heat and drought) on oil content and fatty acid composition in conventional soybean genotypes were summarized for scientists and industry personnel and up to date information on altered fatty acid soybean cultivar soon to be marketed was obtained. This chapter will serve as a scientific resource for the soybean scientific community, especially for breeders developing soybean cultivars for improved seed oil quality under heat and drought stress. Technical Abstract: Previous studies have shown that oil concentration and fatty acid profile (composition) change with genotype, environment (mainly heat and drought), and geographical location. The changes in fatty acid composition under these conditions affect fatty acid stability, creating a challenge to oil processing industry to predict production and oil quality under different environmental conditions. Oil with a lower stability index is subject to oxidation, resulting in degradation of oil, oil-derived products, biodiesel, and biodegradable lubricants. Therefore, oil and fatty acid stability has become a subject of intensive research and a major goal of soybean breeding programs, biotechnology, and the soybean oil industry. Lower saturated fatty acids and higher unsaturated fatty acid contents are desirable for human health. However, these oil traits such as higher oleic acid and lower linoleic (C18:2) and linolenic (C18:3) fatty acids are not conducive for oil oxidative stability and processing. Plant breeding and gene modification strategies are currently being employed by seed companies to design the composition of fatty acids in seed oil for health benefits and increased shelf life after processing. This chapter summarizes the effects of two major environmental factors; heat and drought on oil content and fatty acid composition in conventional soybean genotypes and gives up to date information on altered fatty acid soybean genotypes on the horizon. |
