Oil-producing Crops Research Articles

Productivity of oil crops in the conditions of forest-steppe zone of the Republic of Ingushetia

The paper presents the study conducted in the forest-steppe zone of the Republic of Ingushetia on the productivity of new oilseeds in order to recommend their production as an alternative to traditionally grown crops. The morphobiological characteristics, features of growth and development of spring canola, sunflower, mustard, soybeans and camelina, and their yields are distinguished and described.

Genetic Variability, Heritability and Genetic Advance of Groundnut (<i>Arachis hypogaea</i> L.) Genotypes at Assosa and Kamashi, Western Ethiopia

The lowland areas of Ethiopia have significant potential for increased oil crop production including groundnut. In Benishangul Gumuz Region, groundnut is cultivated in various zones and woredas under rain fed condition. However, due to insufficient improved groundnut varieties found in the region the productivity was low. Testing genotypes for the presence of variations and generation of genetic information is the first step in plant breeding to develop varieties for the targeted area of production. Keeping these in account the current study was conducted with the objectives of determining the genetic variability and trait association and their direct and indirect effects on yield and yield related traits of groundnut genotypes at Assosa and Kamashi zones, Western Ethiopia. Twenty five groundnut genotypes were evaluated in 5 x 5 triple lattice designs. Data were recorded for 16 traits and subjected to ANOVA using SAS software. Further genetic analyses were conducted as per the formula suggested by biometricians. Analyses of variance showed mean square due to genotypes were highly significant (p≤0.01) for all traits studied except seeds pod^-1 at both locations. High heritability value coupled with high genetic advance as percent of mean was observed for primary branches plant^-1, 100-seed weight, dry pod yield and grain yield hectare^-1 at Assosa and Kamashi. Therefore, the current study revealed the presence of considerable variability for most of the traits studied and differences in the performance of the genotypes as there were significant differences among genotypes. Emphasis should be given for dry pod yield hectare^-1, primary branches plant^-1, pods plant^-1 and 100-seed weight to enhance grain yield production.

Host plants as reservoirs of the main oil-producing cabbage crops pests in the eastern forest-steppe of Ukraine

Considering the geographical position of Ukraine, which is Such biotic factor as the vegetation distribution, which is the forage base for most insects, influences their spreading greatly. This connection is strongly expressed among the harmful herbivorous insects. The presence and distribution of the plants which are cultivated or used by humans and on which the insects are fed is certainly the first and basic condition for the emergence of a zone or a breeding ground of harmfulness. The presence of the most preferred by the insects fodder plants often leads to the formation of a zone or a center of the greatest damage (in the presence of other favorable conditions for the existence and reproduction of the pest). In the course of the researches concerning the identification of the host plants as reservoirs of the main oil producing cabbage crops pests which have been conducted in 2011–2014 in the communities (meadows, roadsides of highways and field perimeters) of the Kharkiv district of the Kharkiv region it has been found out the host plants as reservoirs for the dominant pests of the oil producing cabbage crops were dandelion, caustic buttercup, field mustard, hedge mustard, tansy mustard, yellow rocket and field shepherd’s purse. The largest number of species of the host plants as reservoirs was found on the roadsides of highways and along the field perimeters (6 species) and on the meadows (2 species).The cruciferous fleas, rape blossom beetles and cruciferous bugs visited such crops as field mustard, hedge mustard and yellow rocket most often. Field shepherd’s purse was the least significant among the identified host plants as reservoirs. Only a small amount of the cabbage fleas fed on this crop. This fact can be explained by the small white flowers that do not attract the rape blossom beetles and rose chafers as well as by a ground flat leaf rosette, which is always covered with dust and prevents the fleas and bugs from feeding.

Inoculation With the Plant-Growth-Promoting Rhizobacterium Pseudomonas fluorescens LBUM677 Impacts the Rhizosphere Microbiome of Three Oilseed Crops.

The bacterial communities inhabiting the rhizosphere play an important role in plant development and health. Here we studied the effect of inoculation with Pseudomonas fluorescens LBUM677, a plant growth promoting rhizobacterium that promotes seed oil accumulation, on the rhizosphere microbiome of three oilseed crops (Brassica napus, Buglossoides arvensis, and Glycine max) over time. Next-Generation high-throughput sequencing targeting the V4 region of 16S rDNA was used to characterize the microbial communities associated with the three different crops, inoculated or not with LBUM677, over a time period of up to 90 days post-inoculation. A total of 1,627,231 amplicon sequence variants were obtained and were taxonomically grouped into 39 different phyla. LBUM677 inoculation and sampling date were found to significantly influence the rhizosphere microbiome of the three oil-producing crops under study. Specifically, inoculation with LBUM677 and sampling date, but not the plant species, were found to significantly alter the alpha- and the beta-diversity of the rhizosphere microbial communities. Differential abundance analyses found that 29 taxonomical bacterial groups were significantly more abundant in the LBUM677 treatments while 30 were significantly more abundant in the control treatments. Predicted functions of the microorganisms were also enriched, including 47 enzymatic pathways in LBUM677 treatments. These non-targeted effects on rhizosphere bacterial communities are discussed in the context of oilseed crops.

Potassium deficiency reconfigures sugar export and induces catecholamine accumulation in oil palm leaves

Metabolic effects of potassium (K) deficiency have been described for nearly 70 years but specific effects of low K availability on sugar composition, sugar export rate and its relationship with other leaf metabolites are not very well documented. Having such pieces of information is nevertheless essential to identify metabolic signatures to monitor K fertilization. This is particularly true in oil-producing crop species such as oil palm (Elaeis guineensis), which is strongly K-demanding and involves high sugar dependence for fruit formation because of low carbon use efficiency in lipid synthesis. Here, we used metabolic analyses, measured sugar export rates with 13C isotopic labeling and examined the effects of K availability on both leaflet and rachis sugar metabolism in oil palm seedlings. We show that low K leads to a modification of sugar composition mostly in rachis and decreased sucrose and hexose export rates from leaflets. As a result, leaflets contained more starch and induced alternative pathways such as raffinose synthesis, although metabolites of the raffinose pathway remained quantitatively minor. The alteration of glycolysis by low K was compensated for by an increase in alternative sugar phosphate utilization by tyrosine metabolism, resulting in considerable amounts of tyramine and dopamine.

Yield and Yield Attributes of Short Duration Mustard as Influenced by Nutrient Rates

Mustard (Brassica napus)is the important principal edible oil-producing crop in Bangladesh. However, the nutrient requirement of mustard especially for the short duration variety is very much important to obtain higher yield. A field experiment was conducted to assess the requirement of major nutrients (N, P, K, and S), and to recommend fertilizers for short-duration mustard variety BARI Sarisha-14. There were 8 treatments T1=100% soil test based (STB) nutrients (N, P, K, S, Zn & B @ 90, 25, 60, 15, 2 & 1 kg ha-1, respectively) as per Fertilizer Recommendation Guide (FRG,2012), T2=T1+ 25% N of FRG, T3=T1+ 25% NP of FRG, T4=T1+ 25% NK of FRG, T5=T1+ 25% PK of FRG, T6=T1+ 25% NPK of FRG, T7=75% of T1 and T8= native nutrient (control). The experiment was laid out in Randomized Complete Block Design with 3 replications. The results revealed that yield and yield parameters of mustard weresignificantly influenced by the nutrient levels. The highest value of almost all the yield components and yield were obtained in T6 among the treatments. The highest seed yield (1.68 t ha-1) and the maximum stover yield (2.96 t ha-1) were obtained from the treatment (T6) containing 100% STB nutrients with additional 25% NPK among the fertilizer treatments. The seed yield value was statistically higher than all other treatments except the treatment where100% STB nutrients with additional 25% NP were used (T3). The highest seed yield and stover production were attributed tothe yield contributing parameters. The highest amount of all the nutrients content was found in the treatment T6 that was followed by T3 and T4 and the lowest in T8. The highest amount of N, P, K, and S content in seed of the treatment T6 was 3.75, 0.97, 0.96 and 0.78%, respectively. The highest yield was accredited to the highest amount of nutrient content in seed. It could be concluded that the treatment T6 (STB fertilizer dose + 25% NPK of FRG) would suitable for short duration Mustard (BARI Sarisha-14) for getting higher yield and better performance.
 Bangladesh Agron. J. 2019, 22(2): 129-138

Seed Germination in Oil Palm (Elaeis guineensis Jacq.): A Review of Metabolic Pathways and Control Mechanisms.

Oil palm is an oil-producing crop of major importance at the global scale. Oil palm mesocarp lipids are used for myriads industrial applications, and market demand has been growing for decades. In addition, oil palm seeds are oleaginous, and the oil extracted therefrom can be used for several purposes, from food to cosmetics. As such, there is a huge need in oil palm seeds to maintain the global cohort of more than 2 billion trees. However, oil palm seed germination is a rather difficult process, not only to break dormancy, but also because it is long and often reaches lower-than-expected germination rates. Surprisingly, despite the crucial importance of germination for oil palm plantation management, our knowledge is still rather limited, in particular about germinating oil palm seed metabolism. The present review incorporates different pieces of information that have been obtained in the past few years, in oil palm and in other palm species, in order to provide an overview of germination metabolism and its control. Further insights can also be gained from other oleaginous model plants, such as Arabidopsis or canola, however, palm seeds have peculiarities that must be accounted for, to gain a better understanding of germinating seed metabolism.

The Unavoidable Palm Oil Can Be Sustainable

The oil palm is the most productive oil-producing crop. To yield the same volume of oil that is from one hectare of palm, eight hectares of soybean are needed. Palm oil is used an ingredient in over 50% of packaged supermarket products and also as biofuels. The palm oil sector provides over 4.5 million jobs for on-farm laborers in developing countries. However, palm oil is often blamed for deforestation and loss of biodiversity. We argue that palm oil sustainability is not only about the environment and biodiversity but also about people and their prosperity. Palm oil sustainability can be achieved with joint efforts from palm oil players including the smallholders, plantation companies, governments, certification agencies, consumers and researchers.

An integrated approach to improve plant protection against olive anthracnose caused by the Colletotrichum acutatumspecies complex.

The olive tree (Olea europaea L.) is the most important oil-producing crop of the Mediterranean basin. However, although plant protection measures are regularly applied, disease outbreaks represent an obstacle towards the further development of the sector. Therefore, there is an urge for the improvement of plant protection strategies based on information acquired by the implementation of advanced methodologies. Recently, heavy fungal infections of olive fruits have been recorded in major olive-producing areas of Greece causing devastating yield losses. Thus, initially, we have undertaken the task to identify their causal agent(s) and assess their pathogenicity and sensitivity to fungicides. The disease was identified as the olive anthracnose, and although Colletotrichum gloeosporioides and Colletotrichum acutatum species complexes are the two major causes, the obtained results confirmed that in Southern Greece the latter is the main causal agent. The obtained isolates were grouped into eight morphotypes based on their phenotypes, which differ in their sensitivities to fungicides and pathogenicity. The triazoles difenoconazole and tebuconazole were more toxic than the strobilurins being tested. Furthermore, a GC/EI/MS metabolomics model was developed for the robust chemotaxonomy of the isolates and the dissection of differences between their endo-metabolomes, which could explain the obtained phenotypes. The corresponding metabolites-biomarkers for the discrimination between morphotypes were discovered, with the most important ones being the amino acids L-tyrosine, L-phenylalanine, and L-proline, the disaccharide α,α-trehalose, and the phytotoxic pathogenesis-related metabolite hydroxyphenylacetate. These metabolites play important roles in fungal metabolism, pathogenesis, and stress responses. The study adds critical information that could be further exploited to combat olive anthracnose through its monitoring and the design of improved, customized plant protection strategies. Also, results suggest the necessity for the comprehensive mapping of the C. acutatum species complex morphotypes in order to avoid issues such as the development of fungicide-resistant genotypes.

PRODUKSI KELAPA SAWIT (Elais guineensis Jacq.) DENGAN SISTEM PEREMAJAAN YANG BERBEDA

Abstract This study aims to determine the production of oil palm with a different replanting system. The study was conducted in the area of simultaneous fallen replanting system and underplanting system area located in Panca Mulya Village, Sungai Bahar District, Muaro Jambi Regency. The material used in this study was the Tenera variety of oil palm plants aged 4.5 years and 5.5 years. The study used a survey method with systematic sampling method. The main variables observed were plant production as well as physical plant additional variables, soil pH, light intensity, temperature, and humidity. The results showed that the replanting system significantly affected the production of oil palm plants and plant physicality, soil pH, light intensity, temperature, and air humidity. Palm oil crop production is higher in areas with simultaneous fallen replanting systems. Key words: replanting system, oil palm

Melatonin Represses Oil and Anthocyanin Accumulation in Seeds.

Previous studies have clearly demonstrated that the putative phytohormone melatonin functions directly in many aspects of plant growth and development. In Arabidopsis (Arabidopsis thaliana), the role of melatonin in seed oil and anthocyanin accumulation, and corresponding underlying mechanisms, remain unclear. Here, we found that serotonin N-acetyltransferase1 (SNAT1) and caffeic acid O-methyltransferase (COMT) genes were ubiquitously and highly expressed and essential for melatonin biosynthesis in Arabidopsis developing seeds. We demonstrated that blocking endogenous melatonin biosynthesis by knocking out SNAT1 and/or COMT significantly increased oil and anthocyanin content of mature seeds. In contrast, enhancement of melatonin signaling by exogenous application of melatonin led to a significant decrease in levels of seed oil and anthocyanins. Further gene expression analysis through RNA sequencing and reverse-transcription quantitative PCR demonstrated that the expression of a series of important genes involved in fatty acid and anthocyanin accumulation was significantly altered in snat1-1 comt-1 developing seeds during seed maturation. We also discovered that SNAT1 and COMT significantly regulated the accumulation of both mucilage and proanthocyanidins in mature seeds. These results not only help us understand the function of melatonin and provide valuable insights into the complicated regulatory network controlling oil and anthocyanin accumulation in seeds, but also divulge promising gene targets for improvement of both oil and flavonoids in seeds of oil-producing crops and plants.

Soybean: sources from the VIR collection of genetic resources

Soybean is an extremely valuable crop due to its unique biochemical composition, which underpins multifunctional utilization of this crop and high profitability of its industrial and agricultural production. Soybean seeds accumulate up to 45% of high-quality vegetable protein, which is close in composition to the protein of animal origin. Soybean is also of great importance as an oil-producing crop, accumulating up to 28% of oil in its seeds. It is widely used in animal husbandry for the production of maize-soybean silage and haylage. It can also be used as a green manure crop to enrich the soil with nitrogen at the expense of nodule bacteria. High demand and the price make it a highly profitable agricultural crop. It is clear from the above-mentioned advantages that soybean is of great interest to breeders. The Kuban Experiment station of VIR conducts field studies of new soybean cultivars using the practices worked out for leguminous crops at VIR. Three years of research have resulted in identification of promising cultivars, sources and donors of various valuable traits. This article is based on the data obtained from the study of the soybean collection from 2014 to 2016. Accessions k-11385, k-11479, and i-623931 were distinguished for their high yield. The following accessions stood out for their seed productivity per plant: k-1475, k-11472, k-11535, k-11466, k-11478, k-11577, k-11467, and k-11469. The size of seeds was the best in accessions k-11489, k-11491, k-11533, k-11529, k-11537, i-623952, i-623967, i-623980, i-623958, and i-623987. Two accessions appeared noticeable for the height of lower pod attachment: i-623960 and k-11494. All selected accessions can be used in breeding programs as sources of valuable traits.

Do Soil Warming and Changes in Precipitation Patterns Affect Seed Yield and Seed Quality of Field-Grown Winter Oilseed Rape?

Increasing air and soil temperatures and changes in precipitation patterns as consequences of climate change will affect crop production in agricultural ecosystems. The combined effects of soil warming and altered precipitation on the productivity and product quality of oil crops are not yet well studied. Winter oilseed rape (OSR) (Brassica napus L., cv. Mercedes) was field-grown under elevated soil temperature (+2.5 °C), reduced precipitation amount (−25%), reduced precipitation frequency (−50%) both separately and in combination in order to investigate effects on crop development, seed yield, and seed quality. Soil warming accelerated crop development during early plant growth and during spring. At maturity, however, plants in all treatments were similar in quantitative (aboveground biomass, seed yield) and qualitative (protein and oil content, amino acids, fatty acids) parameters. We observed the long-term effects of the precipitation manipulation on leaf size, leaf senescence and biomass allocation. Seed yield was not affected by the altered climatic factors, perhaps due to adaptation of soil microorganisms to permanent soil warming and to relatively wet conditions during the seed-filling period. Overall, OSR performed well under moderate changes in soil temperature and precipitation patterns; thus, we observed stable seed yield without negative impacts on nutritive seed quality.

Plasticity of seed weight in winter and spring rapeseed is higher in a narrow but different window after flowering

Breeding heavier seeds while maintaining seed number has been proposed as an effective strategy to improve oil crop production. Recent studies assessing rapeseed source-sink (S-Sratio) reduction after flowering suggest a window in the early seed-filling period that can compensate, either partially or totally, for a decrease in the number of seeds. However, little evidence has been reported in relation to the key window for seed plasticity in rapeseed. Furthermore, such studies have only assessed spring rapeseed genotypes and there is a lack of information on winter rapeseed. This study aims to elucidate the occurrence of a narrow window when seed plasticity is greatest, which is hypothesized to occur during the early stages of seed filling after the beginning of flowering in both winter and spring rapeseed genotypes. To asses this hypothesis, two winter and two spring rapeseed hybrids were evaluated under three S-Sratio treatments in two experiments performed in field conditions in Valdivia, Chile. The winter hybrids Trust and Mercedes were assessed under different nitrogen levels, and the spring hybrids Lumen and Solar were assessed using two sowing dates. S-Sratio treatments in both rapeseed genotypes consisted of a control without S-Sratio manipulation, a reduced S-Sratio from the beginning of flowering [BBCH 61] to 15 days after flowering (DAF) and a reduced S-Sratio from 15 to 30 DAF. The S-Sratio was reduced by shading the crop with black nets to intercept 75 % of the incoming solar radiation. Shading treatments decreased seed yield relative to the control between 13 and 42 % for the winter genotypes and from 23 to 44 % for the spring genotypes. The negative effect of shading on seed number under both S-S reduction timings explains the seed yield reduction. Interestingly, different windows of time for seed weight plasticity were found in response to the lower S-Sratio for winter and spring genotypes (i.e., 15–30 and 0–15 DAF, respectively). In the winter-type genotypes, seed weight increased between 28 and 33 % under the 15–30 DAF shading treatment, while seed weight in spring-type genotypes increased from 15 to 39 % during the 0–15 DAF treatment. Seed weight change was almost negligible outside of the sensitivity window as this trait increased only 2% at 0–15 DAF in winter-type genotypes and 7% at 15–30 DAF in spring-type genotypes, across treatments. In parallel, the S-S reduction decreased seed number by 23.6 and 40 %, at the 0–15 and 15–30 DAF treatment, respectively. The study showed statistical differences for seed oil and protein concentration across treatments, but both quality traits remained highly stable to the S-S reduction and showed similar behavior in winter and spring rapeseed types. Seed oil concentration changed little while seed protein concentration was more sensitive to seed weight response. The findings of the present study suggest that seeds per silique and seed weight are determined by the plant assimilate S-Sratio; therefore, seed number and seed weight determinations overlap as has been demonstrated in other crops like wheat, barley, sorghum and sunflower.

Potencijali izvoza uljarica iz Srbije

Oil crops are very significant, both in the world and in Serbia. In terms of production, the three most important oil crops in Serbia are sunflower, soybean and rapeseed. Beside significant oil crops production, substantial quantities of oil are produced as well due to significant processing capacities in Serbia. Considering the fact that over the last few decades Serbian market has been characterized by integration with the international market and considering the actual market liberalization with the EU, CEFTA countries, Russia and others, this paper analyses production and export of oil crops with special emphasis on comparative advantages in the export of oil crops using the method of revealed comparative advantage. Also, the level of intra-industry trade is considered in relation to the international market, EU and CEFTA countries. The results indicate that oils have more significant comparative advantage on the international market, especially sunflower oil.

Antimicrobial and cytotoxic potential of seeds and flowers crude extracts of sunflower

Abstract Oil-producing crops, including Helianthus annuus L. (H. annuus, Sunflower), have been used for the treatment of different human diseases since ancient times. This study aims to determine the antimicrobial and cytotoxic potential of different polarities of seeds and flower extracts of locally grown H. annuus by well-established bioassays. To achieve the objects, the plant extracts were prepared from both flowers and seeds powder samples individually with methanol solvent by using a Soxhlet extraction method. The antimicrobial and cytotoxic potential of the flowers and seed extracts were determined by the in vitro diffusion and brine shrimp method (BSL). The results of the antimicrobial potential of both prepared flower and seed extracts of various polarities at different concentrations showed promising potential against the gram-positive and gram-negative bacterial strains, within the range of inhibition zone 0–20 mm. Among the flower extracts, the highest potential was obtained in water extract and the lowest potential was in butanol extract followed by water > ethyl acetate > hexane > methanol > chloroform > butanol extracts. However, from the seed extracts, the highest potential was obtained in water extract and the lowest potential was in the methanol extract followed by water > hexane > butanol > ethyl acetate > chloroform > methanol extract. On the other hand, the results of cytotoxicity among the flowers extracts against the brine shrimp method where the highest LC50 against brine shrimp nauplii were found to be 31.25 μg/mL in water extract and the lowest LC50 was 1345.86 μg/mL in chloroform extract followed by water > ethyl acetate > hexane > butanol > methanol > chloroform extract. Similarly, different polarities of seed extracts, the highest LC50 against brine shrimp nauplii was shown to be 109.56 μg/mL in butanol extract and the lowest LC50 was 1513.56 μg/mL in ethyl acetate extract followed by butanol > hexane > water > methanol > chloroform > ethyl acetate extract. In conclusion, the results showed that both flowers and seeds extracts at various concentrations have promising potential against the positive and negative bacterial strains and the highest potential water extract could be used as natural broad-spectrum antibiotics as herbal medicine to treat different human infectious diseases.

Circular Sustainability Optimisation Model for Diverse Oil Crops Feedstock System via Element Targeting Approach

Need of oil crops for bio-diesel production has been increasing due to its sustainable characteristic as compared to fossil fuel. Nonetheless, effort to ensure sustainable practise along bio-diesel production is essential to prevent back-fire from sustainable development. Each oil crop production and plantation activities are unique, leading to various in sustainability profile. In such context, systematic process optimisation for oil crop utilisation and selection is critical to ensure highest overall sustainable performance in the diverse oil crop system. This research adapts concept of element targeting in multi biomass selection to determine best diverse oil crop utilisation strategic. Various sustainable indexes are considered such as land used, carbon footprint, deforestation, water usage and fertiliser usage are considered. Cost calculation including transportation and production cost is incorporated in the study, while concept of circular economy is incorporated into the model by considering circular carbon element within the system. Demonstration case study is discussed to evaluate the performance of the model. The result shows that rapeseed oil is favourable in highest sustainability case, soybean provide lower cost and sunflower promote less carbon release.

Вплив оптимізації живлення на продуктивність ярих олійних культур на чорноземі південному в зоні Степу України під впливом біопрепаратів

Вплив оптимізації живлення на продуктивність ярих олійних культур на чорноземі південному в зоні Степу України під впливом біопрепаратів

Increasing Inflorescence Dry Weight and Cannabinoid Content in Medical Cannabis Using Controlled Drought Stress

Controlled application of drought can increase secondary metabolite concentrations in some essential oil-producing crops. To evaluate the effects of drought on cannabis (Cannabis sativa L.) inflorescence dry weight and cannabinoid content, drought stress was applied to container-grown cannabis plants through gradual growing substrate drying under controlled environment. Fertigation was withheld during week 7 in the flowering stage until midday plant water potential (WP) was approximately −1.5 MPa (drought stress threshold). This occurred after 11 days without fertigation. A well-irrigated control was used for comparison. Leaf net photosynthetic rate (Pn), plant WP, wilting (leaf angle), and volumetric moisture content (VMC) were monitored throughout the drying period until the day after the drought group was fertigated. At the drought stress threshold, Pn was 42% lower and plant WP was 50% lower in the drought group than the control. Upon harvest, drought-stressed plants had increased concentrations of major cannabinoids tetrahydrocannabinol acid (THCA) and cannabidiolic acid (CBDA) by 12% and 13%, respectively, compared with the control. Further, yield per unit growing area of THCA was 43% higher than the control, CBDA yield was 47% higher, ∆9-tetrahydrocannabinol (THC) yield was 50% higher, and cannabidiol (CBD) yield was 67% higher. Controlled drought stress may therefore be an effective horticultural management technique to maximize both inflorescence dry weight and cannabinoid yield in cannabis, although results may differ by cannabis cultivar or chemotype.

Drought-responsive genes, late embryogenesis abundant group3 (LEA3) and vicinal oxygen chelate, function in lipid accumulation in Brassica napus and Arabidopsis mainly via enhancing photosynthetic efficiency and reducing ROS.

SummaryDrought is an abiotic stress that affects plant growth, and lipids are the main economic factor in the agricultural production of oil crops. However, the molecular mechanisms of drought response function in lipid metabolism remain little known. In this study, overexpression (OE) of different copies of the drought response genes LEA3 and VOC enhanced both drought tolerance and oil content in Brassica napus and Arabidopsis. Meanwhile, seed size, membrane stability and seed weight were also improved in OE lines. In contrast, oil content and drought tolerance were decreased in the AtLEA3 mutant (atlea3) and AtVOC‐RNAi of Arabidopsis and in both BnLEA‐RNAi and BnVOC‐RNAi B. napus RNAi lines. Hybrids between two lines with increased or reduced expression (LEA3‐OE with VOC‐OE, atlea3 with AtVOC‐RNAi) showed corresponding stronger trends in drought tolerance and lipid metabolism. Comparative transcriptomic analysis revealed the mechanisms of drought response gene function in lipid accumulation and drought tolerance. Gene networks involved in fatty acid (FA) synthesis and FA degradation were up‐ and down‐regulated in OE lines, respectively. Key genes in the photosynthetic system and reactive oxygen species (ROS) metabolism were up‐regulated in OE lines and down‐regulated in atlea3 and AtVOC‐RNAi lines, including LACS9,LIPASE1,PSAN,LOX2 and SOD1. Further analysis of photosynthetic and ROS enzymatic activities confirmed that the drought response genes LEA3 and VOC altered lipid accumulation mainly via enhancing photosynthetic efficiency and reducing ROS. The present study provides a novel way to improve lipid accumulation in plants, especially in oil production crops.