Soybean seed protein, oil, fatty acids, and mineral composition as influenced by soybean-corn rotation

Effects of crop rotation on soybean (Glycine max (L) Merr.) seed composition have not been well investigated. Therefore, the objective of this study was to investigate the effects of soybean-corn (Zea mays L.) rotations on seed protein, oil, and fatty acids composition on soybean. Soybeans were grown at Stoneville, MS, from 2005 to 2008 in five different scheduled cropping sequences. In 2007, following three years of rotation with corn, seed oleic acid percentage was significantly higher in any crop rotation than continuous soybean. The increase of oleic fatty acid ranged from 61 to 68% in 2007, and from 27 to 51% in 2008, depending on the rotation. The increase of oleic acid was accompanied by significant increases in seed concentrations of phosphorus (P), iron (Fe), and boron (B). In 2007, the increase of P ranged from 60 to 75%, Fe from 70 to 72%, and B from 34 to 69%. In 2008, the increase of P ranged from 82 to 106%, Fe from 32 to 84%, and B from 62 to 77%. Continuous soybean had higher linoleic:oleic ratio and linoleic: palmitic + stearic + oleic ratio, indicating that relative quantity of linoleic acid decreased in rotated crops. The total production of protein, oil, stearic and oleic fatty acids was the lowest in continuous soybean. The total production of palmitic acid was inconsistent across years. The results show that soybean- corn rotation affects seed composition by consistently increasing seed oleic fatty acid, P, Fe, and B concentrations. Higher oleic acid, unsaturated fatty acid, is desirable for oil stability and long-shelf storage. The mechanisms of how these nutrients are involved are not yet understood.

Fatty Acid Composition of Hazelnut Kernel Oil from Coula edulis Collected in the Republic of Congo

Coula edulis is non-timber forest product (NTFP) used in Africa for its hazelnuts, which contain edible seeds with a demonstrated nutritional potential. However, there have been very few scientific studies of this species in the Republic of Congo. Thus, the aim of the current study was therefore to determine the fatty acid composition of the oil extracted from Coula edulis hazelnut seeds collected at random in the Republic of Congo. The oil was extracted using the Soxhlet method and its fatty acid composition was determined by gas chromatography. The extracted oil from Coula edulis hazelnut kernels is rich in monounsaturated fatty acids (95.28%), particularly oleic acid (94.5%), which classifies it as an oleic oil and gives it interesting nutritional and therapeutic properties. On the other hand, saturated fatty acids (4.15%) and polyunsaturated fatty acids (0.35%) are not well represented. Its low poly-unsaturated fatty acid content makes it more stable when stored at room temperature.

Diversity in seed oil content and fatty acid composition in Acer species with potential as sources of nervonic acid

Nervonic acid(NA,cis-15-tetracosenoic acid)is a very long-chain monounsaturated fatty acid that has been shown to be a core component of nerve fibers and nerve cells.It can be used to treat and prevent many neurological diseases.At present,commercially available NA is mainly derived from Acer truncatum seeds,which contain about 5%e6%NA in their seed oil.The aim of this study were to identify and analyze NA-containing Acer species that could be used as NA resource plants.For this purpose,46 Acer species seeds were collected in China and in some or all of the seed oils from these species 15 fatty acids were detected,including linoleic acid,oleic acid(C18:1D9,C18:1D11),erucic acid,palmitic acid,NA,linolenic acid(C18:3D6,9,12,C18:3D9,12,15),eicosenoic acid(C20:1D11,C20:1D13),stearic acid,behenic acid,tetracosanoic acid,arachidic acid,and docosadienoic acid.Nervonic acid was detected in all samples,but the content was highly variable among species.NA content over 9%was detected in eleven species,of which Acer elegantulum had the highest levels(13.90%).The seed oil content,seed weight,and fatty acid profiles varied among species,but the comprehensive evaluation value(W)showed that A.coriaceifolium could be a new potential NA resources plant.The results also showed that NA was significantly negatively correlated with palmitic acid,oleic acid,and eicosenoic acid,but positively correlated with eicosadienoic acid,behenic acid,erucic acid,and tetracosanoic acid,which indicate the probable pathway for NA biosynthesis in Acer plants.This study has identified Acer species that may serve as NA resources and will help guide subsequent species breeding programs.

Effects of chelating agents on protein, oil, fatty acids, and minerals in soybean seed

Soybean seed is a major source of protein and oil for human diet. Since not much information is available on the effects of chelating agents on soybean seed composition constituents, the current study aimed to investigate the effects of various chelating agents on soybean [(Glycine max (L.) Merr.)] seed protein, oil, fatty acids, and mineral concentrations. Three chelating agent [citric acid (CA), disodium EDTA (DA), and Salicylic acid (SA)] were applied separately or combined with ferrous (Fe2+) ion (CA + Fe, EDTA + Fe, and SA + Fe) to three-week-old soybean plants. After application, the plants were allowed to grow until harvest maturity under greenhouse conditions. The results showed that CA, DA, SA, and Fe resulted in an increase of oleic acid from 13.0% to 33.5%. However, these treatments resulted in a decrease of linolenic acid from 17.8 to 31.0%. The treatments with CA and SA applications increased protein from 2.9% to 3.4%. The treatments DA + Fe and SA + Fe resulted in an increase in oil from 6.8% to 7.9%. Seed macro- and micro-elements were also altered. The results indicated that the CA, SA, DA, and Fe treatments can alter seed protein, oil, fatty acids, and mineral concentrations. Further studies are needed for conclusive results.

Seed protein, oil, fatty acids, and minerals concentration as affected by foliar K-glyphosate applications in soybean cultivars

Previous studies showed that glyphosate (Gly) may chelate cation nutrients, including potassium (K), which might affect the nutritional status of soybean seed. The objective of this study was to evaluate seed composition (protein, oil, fatty acids, and minerals) as influenced by foliar applications of K + Gly. A greenhouse experiment was conducted at Mississippi Valley State University, using two glyphosate-resistant soybean cultivars DK 4968 and Pioneer 95Y70 grown in a randomized complete block design. The treatments were foliar applications of K alone, Gly alone, K + Gly combined, and nontreated control (C). A single application of potassium (1.75% as K2SO4) was applied, and Gly was applied at a rate of 0.75 ae/ha at V5 stage. Leaf samples were harvested one week after treatment (1WAT) and 3WAT. Mature seeds were collected at harvest maturity (R8). The results showed that K, nitrogen (N), and phosphorus (P) concentrations increased in leaves in K alone and K + Gly treatments at 1WAT, but significantly increased at 3WAT in all treatments. The concentration of iron (Fe) and zinc (Zn) showed a decrease in leaf concentration in Gly and K + Gly treatments compared to C. Boron (B) concentration increased in Gly treatment. Seed protein percentage was higher in all treatments in cultivar DK 4968, and the increase was about 4.0% in K treatment, 6.9% in Gly treatment, and 3.5% in K + Gly treatment compared to C. The opposite trend was observed in oil concentration, especially in Gly treatment where the percentage decrease was 11.2% compared to C. Stearic fatty acid was significantly higher in K + Gly treatment compared to K treatment for DK 4968. A higher percentage increase in linolenic acid was observed in DK 4968 in K treatment (an increase of 24.5%) and in K + Gly treatment (an increase of 29.5%) compared to C. In Pioneer 95Y70, the decrease in oil was 2.7% in K treatment and 2.3% in K + Gly treatment compared to C. Stearic acid in Pioneer 95Y70 was significantly higher in Gly treatment, an increase of 8.3%, compared to C. Our research demonstrated that foliar application of K and Gly altered mineral concentration in leaves and shifted seed composition towards protein and stearic concentration. Further research under field conditions is needed before final conclusions are made.

Soybean seed protein, oil, and fatty acids are altered by S and S + N fertilizers under irrigated or non-irrigated environments

Information on the effect of sulfur (S) or sulfur+nitrogen (S + N) on soybean seed composition is scarce. Thus, the objective of this study was to investigate the effects of S, and S + N fertilizers on soybean [(Glycine max (L.) Merr.)] seed composition in the Early Soybean Production System (ESPS) under irrigated (I) and nonirrigated (NI) environments. Two separate field experiments were conducted from 2005 to 2007. One experiment was irrigated, and the second experiment was nonirrigated. Under I condition, S at a rate of 44.8 kg/ha alone or with N at 112 kg/ha resulted in a consistent increase in seed protein and oleic acid concentrations, and a decrease in oil and linolenic acid concentrations compared with the control (C). For example, in 2006 and compared with the C, application of S + N increased the percentage up to 11.4% and 48.5% for protein and oleic acid, respectively. However, oil concentration decreased by 3%. Protein and oleic acid increase were accompanied by a higher percentage of leaf and seed N and S. Under NI conditions, seed protein and oleic acid concentrations were significantly higher in C than in any S or S + N treatments, but the oil and linolenic acid concentrations were significantly lower. The results indicate that specific rate of S alone or S + N combined can alter seed composition under irrigated or nonirrigated conditions. This knowledge may help plant breeders to develop and release cultivars to suit specific target locations to grow new value-added soybeans or select for specific seed composition traits under specific environmental stress factors such as drought.

Quality, fatty acid composition and oxidation stability of ten cold-pressed seed oils

Cold-pressed oils from six herb plant seeds and four woody plant seeds were analyzed and compared for their quality characteristics such as oil, crud protein, shell, and moisture content, fatty acid （FA） compositions and oxidation stability. Results showed that walnut kernel contained the greatest amount of seed oil and safflower seed contained the lowest. Safflower, pumpkin, hemp, camellia and peony seeds had high shell content, their kernel oil content significantly increased after shelling. These oils had significant differences （p〈0.01） in levels of fatty acids and the ratio of n-6：n-3 fatty acids. Camellia, safflower, and flax seed oil contained the highest oleic acid, linoleic acid, and a-linolenic acid respectively. Hemp seed oil was observed in a 3.53：1 ratio of n-6 and n-3 fatty acids. All these ten oils were obviously different in moisture and volatile content, acid value, peroxide value and induction period （IP） （p〈0.01）. IP of peony seed oil was lowest （0.94 h） and almond oil was the highest （14.10 h）. IP of oils negatively correlated with polyunsaturated fatty acids content ^=-0.664, p=0.036）. These studies of ten cold-pressed oils may provide better explanation for their potential health benefits and further developing their commercial value.

Soybean Seed Protein, Oil, Fatty Acids, and Isoflavones Altered by Potassium Fertilizer Rates in the Midsouth

Previous research has shown that the effect of potassium fertilizer on soybean ([Glycine max (L.) Merr.] seed composition (protein, oil, fatty acids, and isoflavones) is still largely unknown. Therefore, the objective of this research was to investigate the effects of potassium application on seed protein, oil, fatty acids, and isoflavones under Midsouth environmental conditions. A three-year experiment was conducted in two locations (Milan, TN and Jackson, TN). Potassium (K) rates were applied in the form of K2O at a rate of 0 (Control, C), 45 (T1), 90 (T2), 134 (T3), and 179 (T4) kg·ha-1 in a randomized complete block design. The results showed that increasing the K application rate did not result in consistent effects on yield. However, increasing K application rate did increase protein, oleic acid, and individual and total isoflavone concentrations at both locations in 2008 and 2009. In Jackson in 2010, the increase of K rate did not change oleic acid, but resulted in an increase in glycitein and genistein isoflavone concentrations. In 2010, increasing K application rate increased protein concentrations, decreased individual and total isoflavones, and did not change oleic acid concentration at Milan. At the highest rate of K, 179 kg·ha-1, yield and some seed composition constituents were negatively impacted. Generally, K concentration in leaves at V5, R1, R3, and seed at harvest maturity stage (R8) increased with the increase of K rate applications. The research demonstrated that K application can alter seed composition, but this alteration depended on location, environmental stress factors, mainly heat and drought, K level in soil, and K application rate. Higher rates of K application may negatively impact seed composition constituents.

Effect of Increased Nitrogen Application Rates and Environment on Protein, Oil, Fatty Acids, and Minerals in Sesame (<i>Sesamum indicum</i>) Seed Grown under Mississippi Delta Conditions

Information on the effect of nitrogen fertilizer rates and environment on sesame seed composition and nutrition is scarce. The objective of this research was to investigate the effects of nitrogen fertilizer application rates on sesame seed yield, protein, oil, fatty acids, and mineral nutrition. A two-year (2014, 2015) field experiment was conducted. Nitrogen fertilizer (urea ammonium nitrate) solution (UAN, 32% N) was applied by side dressing to four sesame varieties (S-34, S-35, S-38, S-39) at rates of 44.7, 67.2, 89.6 and 112.0 kg·ha-1. Rate of 44.7 kg·ha-1 was used as control since this rate is traditionally recommended in the region. Increasing nitrogen application rates resulted in higher protein and oleic acid contents in two varieties in 2014, and in all varieties in 2015. Increased protein and oleic acid were accompanied by lower total oil and linoleic acid. Increased nitrogen application also resulted in higher seed N, S, B, Cu, Fe, and Zn in 2014 in S-34 and S-35, but either a decline or no clear change was observed in seed levels of these nutrients in S-38 and S-39. In 2015, increased nitrogen application resulted in significantly higher seed N in all varieties, and higher S, B, Cu, Fe, and Zn in some varieties. A significant positive correlation was observed between nitrogen application rate and yield, and with seed levels of protein, oleic, acid, N, B, Cu, Fe, and Zn. A significant negative correlation was observed between nitrogen application rate and seed oil and linoleic acid. Thus, increased nitrogen fertilizer application resulted in higher seed protein, oleic acid, and some mineral nutrients, but lower oil and linoleic acid. However, this effect depended on variety and environmental conditions. Because higher protein and oleic acid are desirable traits for sesame seed nutritional value and oil stability, regional breeders should select sesame varieties for efficient fertilizer response.

Fatty Acid Compositional Studies of Lesser Known <i>Acacia tortilis</i>Seed Oil

A. tortilis is commonly known as “Israeli babool”. The species is exposed to the world for its pods, gum and other aerial parts as fodder &feed for cattles. The plant was used as antidiabetic, antidiarrhoeal, antiasthmatic and also had several other medicinal benefits but the seed oil was not explored to the extent of its real potential. Hence the study was carried out to characterize the seed for oil and analysis of fatty acid composition through GC for quality control and maintenance. Commercial indices of oil were also estimated. Extracted oil is rich in Linolenic acid (50.43%) and Linoleic acid (36.74%). Beside this palmitic, stearic and oleic acid are other fatty acids identified. MUFA, PUFA, SFA and omega-6/ omega-3 ratio were also found to be promising for its potentiality in edible and clinical uses. The investigation thus scopes the utility of oil and prospects the lesser known plant seed as alternative oil source of nutritional and therapeutic importance.

Physicochemical and Biochemical Composition of Balanites aegyptiaca Seed and Seed Oil from Burkina Faso

In Burkina Faso, the seeds of Balanites aegyptiaca have been considered to be potentially high lipid, protein and mineral sources but seem to be neglected and sometimes unknown by communities. This study aims to complete data on seed oil and detail on amino acids and minerals composition of the seed of B. aegyptiaca for better use. Physicochemical parameters such as moisture and ash content, saponification index, iodine, acid value, peroxide value and the melting point were determined. Seed oil triglycerides, fatty acids and amino acids have been estimated throughout this study. The moisture and ash content were 3.70% ± 0.1% and 2.90% ± 0.2%, respectively. The saponification and iodine values were respectively 181.96 ± 0.4 mg KOH/g of oil and 104.86 ± 0.6 g of iodine/100 g of oil. Polyunsaturated fatty acid content (50.94%) was the most important. Triglyceride (LLO, 22.4%) was the major triglyceride. 9 essential amino acids and 9 non-essential amino acids were identified. Phenylalanine (11697.82 ± 0.00 mg/kg) was the most important essential amino acid. The content of 21 minerals was determined and the most important was potassium (9323.13 ± 0.01 mg/kg). Ca/P, Ca/Mg, Ca/Mg and Na/K ratios were 0.34;1.18;0.04 and 0.19 respectively. B. aegyptiaca seed oil is a source of multiple nutritional values and can be used by the population for multipurpose.

Chia (<i>Salvia hispanica</i>L.) Seed Oil Rich in Omega-3 Fatty Acid: A Healthy Alternative for Milk Fat in Ice Milk

Chia seed oil (Salvia hispanica L.) contains polyunsaturated omega-3 fatty acids and natural antioxidants that have many health effects. Consequently, the chief purpose of the present study was the outcome of various attentiveness of chia seed oil on quality and sensory evaluation of ice milk. In treatments T1, T2, T3, and T4, the milk fat was moderately swapped with chia seed oil at 10%, 20%, 30%, and 40%, respectively, and compared with the control treatment (100% milk fat). All treatments were stored at -18°C for 30 days. Samples were analyzed fortnightly and monthly to determine the shelf life during the storage period by acidity and peroxide value. Physicochemical properties of fatty acids, total polyphenols, and total flavonoids of chia seed oil and ice milk samples were determined. Also, the overrun and sensory evaluation of ice milk samples were studied. Results indicated an increase in the absorption of omega-3 fatty acids (linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic “in the samples of” ice milk supplemented with chia seed oil compared with control. Furthermore, there has been an increase in natural antioxidants (total phenolic and total flavonoid contents) levels in the supplemented ice milk samples as compared to control. Furthermore, an increase in the shelf life of the supplemented ice milk samples was also noticed. Generally, fortification of ice milk with chia seed oil increased the concentration of omega-3 fatty acids and also improved the antioxidant properties of ice milk.

Simplex - Centroid Mixture Design Applied to theAqueous Enzymatic Extraction of Fatty Acid - BalancedOil from Mixed Seeds

A one-step method was developed to extract oil from a mixture of soybeans,peanuts,linseeds,and tea seeds using an aqueous enzymatic method.The proportion of the four seeds was targeted in accordance with a fatty acid ratio of 0.27(SFA,saturated fatty acid(s))∶1(MUFA,monounsaturated fatty acid(s))∶1(PUFA,polyunsaturated fatty acid(s)),and the oil extraction yield was maximized by applying the simplex-centroid mixture design method.Three models were developed for describing the relationship between the proportion of the individual seeds in the mixture,the fatty acid ratio in the extracted oil,and the oil extraction yield,respectively.The developed models were then analyzed using an ANOVA and were found to fit the data quite well,with R2 values of 0.98,0.93,and 0.93,respectively.The three models were validated experimentally.The results indicated that the ratio of fatty acids in the oil ranged between 0.98 and 1.12(MUFA∶PUFA)and between 0.26 and 0.28(SFA∶MUFA),which were quite close to the target values of 1 and 0.27,respectively.The oil extraction yield of 62.13%was slightly higher than the predicted value(60.32%).

Fatty acid analysis in the seeds of 50 Paeonia ostii individuals from the same population

Tree peony seeds are rich in α-linolenic acid(ALA), and the peony seed oil is now being produced in China. Paeonia ostii is the most widely used tree peony species for oil extraction, which is commercially called Fengdan and treated as a single cultivar. Here, 50 P. ostii individuals from the same population in northern China were randomly selected for fatty acids(FAs) analysis. Thirteen FAs were isolated, and the most abundant five were palmitic acid(5.31–6.99%), stearic acid(1.22–2.76%), oleic acid(18.78–28.15%), linoleic acid(11.86–26.10%), and ALA(41.11–57.51%). There were significant individual differences of plants in FA quality and quantity and the linoleic acid content in Plant No. 48 even exceeded the scope of 1–99%. Further statistical analysis indicated that most of the individual FAs, saturated FAs, unsaturated FAs, and total FAs levels showed significant positive correlations to each other, whereas the seed yield per plant was independent and not correlated to the factors mentioned above. Ward’s hierarchical clustering results grouped the 50 plants into four clusters based on FA contents and seed yield, and the seven plants in Cluster IV were identified as good candidates for oil production. Our results confirmed that the individual differences did occur in P. ostii and Fengdan cannot be simply treated as one uniform cultivar. Also, these results may help simplify the selection of plants for oil peony breeding and accelerate the development of the oil peony industry.

<i>Wrinkled</i>1 (WRI1) Homologs, AP2-Type Transcription Factors Involving Master Regulation of Seed Storage Oil Synthesis in Castor Bean (<i>Ricinus communis</i>L.)

Among APETALA2 (AP2)-type plant specific transcription factor family, WRINKLED1 (WRI1), has appeared to be a master gene transcriptionally regulating a set of carbon metabolism- and fatty acid synthesis (FAS)-related genes responsible for seed specific triacylglycerols (TAGs) storage in oil plants. B3 type transcription factors, such as ABI3 and FUS3, are known to be involved in seed development, such as seed storage protein synthesis and maturation. Based on the recent whole genome sequence data of castor bean (Ricinus communis L.), putative WRI1 homologs (RcWRI1, RcWRI2) specifically expressed in castor bean seed have been identified by comparing organ specific expression profiles among seed development-related transcription factors, seed storage specific genes (Ricin, RcOleosin) and a set of FAS genes including genes for sucrose synthase (RcSUS2), biotin carboxyl carrier protein (a subunit of acetyl-CoA carboxylase, RcBCCP2) and ketoacyl-acyl carrier protein synthase (RcKAS1). Immunoreactive signals with WRI1, FUS3 and ABI5-related polypeptides were also detected in seed specifically, consistent with the expression profiles of seed development-related genes. The WRI1 binding consensus sites, [CnTnG](n)(7)[CG], designated as the AW-box, were found at the promoter region of RcBCCP2 and RcKAS1. Thus, RcWRI1 possibly play a pivotal role in seed specific TAGs storage during seed development by directly activating FAS -related genes.

Response Surface Optimization of Nigella glandulifera Freyn Seed Oil Yield by Supercritical Carbon Dioxide Extraction

Supercritical carbon dioxide （SC-CO2） extraction was employed to extract oil from Nigella glandulifera Freyn seed in this study. Response surface methodology （RSM） was applied to evaluate the effects of the process parameters （pressure, temperature, and CO2 flow rate） on oil yield of N. glandulifera seed. A Box-Behnken design was used to optimize the extraction parameters. The analysis of variance indicated that the linear coefficients of pressure and CO2 flow rate, the quadratic term coefficients of pressure and temperature and the interactions between pressure and temperature, as well as temperature and CO2 flow rate, had significant effects on the oil yield （P〈0.05）. The optimal conditions to obtain the maximum oil yield from N. glandulifera seed were pressure 30.84 MPa, temperature 40.57°C, and CO2 flow rate 22.00 L h-1. Under these optimal conditions, the yield of oil was predicted to be 38.19%. The validation experiment results agreed with the predicted values. The fatty acid composition of N. glandulifera seed oil extracted using SC-CO2 was compared with that of oil obtained by Soxhlet method. The results showed that the fatty acid compositions of oil extracted by the two methods were similar. Identification of oil compounds with gas chromatography-mass spectrometry （GC-MS） showed that the contents of unsaturated fatty acids linoleic acid （48.30%）, oleic acid （22.28%） and saturated fatty acids palmitic acid （16.65%）, stearic acid （4.17%） were the most abundant fatty acids in seed oil from N. glandulifera.

Transcriptional proffling between yellow-and black-seeded Brassica napus reveals molecular modulations on flavonoid and fatty acid content

Brassica napus is an important cash crop broadly grown for the vegetable and oil values.Yellow-seeded B.napus is preferred by breeders due to its improved oil and protein quality,less pigments and lignin compared with the blackseeded counterpart.This study compared the differences in flavonoid and fatty acid contents between yellow rapeseed from the progenies of B.napus-Sinapis alba somatic hybrids and the black-seeded counterpart using RNA-seq analysis.Through HPLC-PDA-ESI(-)/MSanalysis,it was found that phenylpropanoids and flavonoids(i.e.,isorhamnetin,epicatechin,kaempferol,and other derivatives)in yellow seed were significantly lower than those in black seed.The fatty acid(FA)content in yellow rapeseed was higher than that in black rapeseed due to the variation of C16:0,C18:0,C18:1,C18:2,and C18:3 contents.RNA-seq analysis of seeds at four and five weeks after flowering(WAF)indicated that differentially expressed genes(DEGs)between black and yellow rapeseeds were enriched in flavonoid and FA biosynthesis,including BnTT3,BnTT4,BnTT18,and BnFAD2.Also,genes related to FA biosynthesis,desaturation and elongation(FAD3,LEC1,FUS3,and LPAT2)in yellow seed were up-regulated compared to those in black seed,while genes involved in beta-oxidation cycle(AIM1 and KAT2)of yellow seed were down-regulated compared to those in black seed.The DEGs related to the variation of flavonoids,phenylpropanoids,and FAs would help improve the knowledge of yellow seed character in B.napus and promote rapeseed improvement.

Effects of Genetics and Environment on Fatty Acid Stability in Soybean Seed

Although seed oil production and composition are genetically controlled, changes of oil level and oil composition across genotypes and environments such as drought and temperature were observed. The mechanisms of how genotypes interact with environment, affecting oil production and composition, are still not well understood. The objective of this research was to investigate the effect of drought/water stress and temperature on soybean genotypes. Two soybean genotypes of maturity group (MG) II (PI 597411 B and PI 597408) and two of MG VI (Arksoy and PI 437726) were used. A repeated greenhouse experiment to study the effect of water stress and a repeated growth chamber experiment to study the effect of temperature were conducted. The results showed that both water stress and high temperature altered seed oil composition by increasing oleic acid and decreasing linoleic and linolenic acid concentrations. Severe water stress (soil water potential between -150 to -200 kPa) or high temperature (40/33℃, day/night) resulted in higher palmitic acid and lower stearic acid. Genotypes differed in their responses to water stress or temperature. Analyses of seed carbohydrates (glucose, fructose, sucrose, raffinose, and stachyose) showed a significant decline of glucose, fructose, and sucrose and a significant increase of stachyose concentration by water stress and high temperature. Analyses of natural abundance of δ15N and δ13C isotopes showed changes in sources of nitrogen and carbon fixation, possibly affecting nitrogen and carbon metabolism pathways. The research demonstrated that both water stress and high temperature altered oil production and composition, and this could be partially related to limited availability and movement of carbohydrates from leaves to seed. Further research to investigate the enzymes controlling fatty acids conversion and nitrogen and carbon metabolism is needed.

Effects of GA3 and NAA on Fatty Acid Degradation in Germination and Seedling Growth of Cassia obtusifolia L. Seed

[Objectives]To understand the content changes of fatty acid compositions and seedling growths during seed germinations of Cassia obtusifolia L.[Methods]The fatty acid compositions of germinations and seedling growths of C.obtusifolia seeds treated with different concentrations of gibberellin(GA3)and naphthalene acetic acid(NAA)were analyzed using gas chromatograph-mass spectrometer(GC-MS),and the germination rates,root lengths,plant heights and fresh weights of their seedlings were analyzed.[Results]The contents of eicosenoic acid,α-linoleic acid,arachidic acid,eicosadienoic acid and eicosapentaenoic acid of C.obtusifolia seeds treated with different concentrations of GA3 and NAA decreased with germination time.There were significant differences between the ratios of germinations of C.obtusifolia seeds treated with different concentrations of GA3 and NAA.GA3 and NAA of different ratio treatments could promote seedling heights and fresh weights of C.obtusifolia,but increases of seedling heights and fresh weights were different.Eicosenoic acid,α-linoleic acid,arachidic acid,eicosadienoic acid and eicosapentaenoic acid were remarkably negative correlation with seedling heights and fresh weights.[Conclusions]The fatty acid components of C.obtusifolia seed germination and growth of their seedlings were affected.It indicated that GA3 and NAA treatments can affect fatty acid metabolism,the germination rates,root lengths,plant heights and fresh weights of C.obtusifolia.It is intended to provide a theoretical basis and technological reference for standardized cultivated techniques of C.obtusifolia.

Seed-specific overexpression of cotton GhDGAT1 gene leads to increased oil accumulation in cottonseed

As the main byproduct of cotton fiber,the cotton seed yields about 1.6 times that of fiber,with its oil rich in unsaturated fatty acids,mainly linoleic acid.It is desirable for breeders to increase the oil content of cottonseed without affecting the yield and quality of cotton fiber.In this study,a seed-specific promoter-(alpha-globulin gene promoter-)driven GhDGAT1 overexpression vector(P_(aGlob)-GhDGAT1)was constructed and used to transform an upland cotton line YZ1(Gossypium hirsutum).Overexpression of the cotton gene GhDGAT1 in cotton seeds increased its total oil content from 4.7%to 13.9%in different transgenic lines and different generations.With the increase of oil content,the composition and contents of the main fatty acids in cotton seed also changed,as reflected by the contents of the main saturated fatty acids and unsaturated oleic acid.GhDGAT1 could be used to increase oil content and improve oil composition in cottonseed.