PLDα1-knockdown soybean seeds display higher unsaturated glycerolipid contents and seed vigor in high temperature and humidity environments

Abstract

BackgroundSoybean oil constitutes an important source of vegetable oil and biofuel. However, high temperature and humidity adversely impacts soybean seed development, yield, and quality during plant development and after harvest. Genetic improvement of soybean tolerance to stress environments is highly desirable.ResultsTransgenic soybean lines with knockdown of phospholipase Dα1 (PLDα1KD) were generated to study PLDα1′s effects on lipid metabolism and seed vigor under high temperature and humidity conditions. Under such stress, as compared with normal growth conditions, PLDα1KD lines showed an attenuated stress-induced deterioration during soybean seed development, which was associated with elevated expression of reactive oxygen species-scavenging genes when compared with wild-type control. The developing seeds of PLDα1KD had higher levels of unsaturation in triacylglycerol (TAG) and major membrane phospholipids, but lower levels of phosphatidic acid and lysophospholipids compared with control cultivar. Lipid metabolite and gene expression profiling indicates that the increased unsaturation on phosphatidylcholine (PC) and enhanced conversion between PC and diacylglycerol (DAG) by PC:DAG acyltransferase underlie a basis for increased TAG unsaturation in PLDα1KD seeds. Meanwhile, the turnover of PC and phosphatidylethanolamine (PE) into lysoPC and lysoPE was suppressed in PLDα1KD seeds under high temperature and humidity conditions. PLDα1KD developing seeds suffered lighter oxidative stresses than did wild-type developing seeds in the stressful environments. PLDα1KD seeds contain higher oil contents and maintained higher germination rates than the wild-type seeds.ConclusionsThe study provides insights into the roles of PLDα1 in developing soybean seeds under high temperature and humidity stress. PLDα1KD decreases pre-harvest deterioration and enhances acyl editing in phospholipids and TAGs. The results indicate a way towards improving production of quality soybean seeds as foods and biofuels under increasing environmental stress.Electronic supplementary materialThe online version of this article (10.1186/s13068-018-1340-4) contains supplementary material, which is available to authorized users.

Novel ethanol production using biomass preprocessing to increase ethanol yield and reduce overall costs

“…These non-structural components (NSC) are non-chemically bound components of lignocellulosic biomass that can directly affect pretreatment, enzymatic hydrolysis, and fermentation yields. Previous studies reported that ash increases the buffering capacity of the biomass, which negatively affects pretreatment efficiency [ 6 – 8 ]. Besides, Ranatunga et al [ 9 ] reported that extractives from hardwoods can inhibit xylose fermentation by Zymomonas mobilis due to their antimicrobial properties, which directly reduces the ethanol yield.…”

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Quantitative proteomic, physiological and biochemical analysis of cotyledon, embryo, leaf and pod reveals the effects of high temperature and humidity stress on seed vigor formation in soybean

“…Temperature and humidity are two of the pivotal environmental factors associated with seed growth and development in field. High temperature and humidity condition can not only affect seed yield and quality, but also reduce seed vigor and storage capacity [1,2], resulting in the preharvest seed deterioration. Seed vigor is a complex property that determines the seed's potential for rapid uniform germination and subsequent growth [3].…”

Mutations of OsPLDa1 Increase Lysophospholipid Content and Enhance Cooking and Eating Quality in Rice

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