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International audience; Camelina has emerged in the last decade as a multipurpose crop plant particularly suitable for engineering new lipids for diverse uses, including feed, biofuel and green chemistry. The rebirth of this ancient crop was based on several intrinsic favorable characteristics: robust agronomic qualities, attractive oil profile, genetic proximity with the model plant arabidopsis, ease of genetic transformation by floral dip. The need to increase both the production and diversity of plant oils, while improving the sustainability of agricultural systems, has been the driving forces behind the ever-increasing investment in camelina research. Worldwide interest in engineering camelina has led to the development of a remarkable pipeline that allows the rapid production and phenotyping of new lines; it includes specific tools, such as databases, collections of natural accessions, methods of genetic transformation and lipid analysis. Implementation of numerous metabolic pathways in camelina for the production of novel lipids has highlighted the potential as well as the versatility of this new "old" oilseed crop that is well on the way to becoming an ideal plant chassis for lipid synthetic biology.

International audience; The potential interest of a dynamic crop model is to provide reliable predictions of oil concentration (OC) soon before harvest as well as helping to understand at which time oil dynamics was affected by environmental stresses or management. For that pm·pose, we proposed a "source-sink" based dynamic model describing on a daily step nitrogen and carbon assimilations and remobilizations during sunflower grain filling. Priority rules were established for C and N depletion from "source" organs, as well as for their allocation into "sink" organs. Photosynthesis was simulated using the radiation use efficiency approach and nitrogen uptake according to Pan et al. (2006) fonnalisms. Water and N stresses were computed by SUNFLO crop model from climatic and soil data find genotype characteristics. The "source" and "sink" variables were initialized at flowering and main outputs were oil and protein concentrations and weights per m2 . The model was calibrated on 24 crop situations in 2012 and evaluated independently on 50 other situations (3 years) with contrasted genotypes and environments. Global trends were well reproduced for all "source" and "sink" components but most variables tended to be overestimated. The main indicators of model quality for predicting OC were: RMSE = 6.1 (%), efficiency = 0.97, R2 = 0.94 and Bias = -0.06 (%). A sensitivity analysis suggested us to reduce the number of parameters, better describe photosynthesis and N uptake processes, and improve the parameterization of genotype and nitrogen effects in order to decrease the prediction error and provide a relevant tool for OC prediction.

The potential interest of a dynamic crop model is to provide reliable predictions of oil concentration (OC) soon before harvest as well as helping to understand at which time oil dynamics was affected by environmental stresses or management. For that pm·pose, we proposed a "source-sink" based dynamic model describing on a daily step nitrogen and carbon assimilations and remobilizations during sunflower grain filling. Priority rules were established for C and N depletion from "source" organs, as well as for their allocation into "sink" organs. Photosynthesis was simulated using the radiation use efficiency approach and nitrogen uptake according to Pan et al. (2006) fonnalisms. Water and N stresses were computed by SUNFLO crop model from climatic and soil data find genotype characteristics. The "source" and "sink" variables were initialized at flowering and main outputs were oil and protein concentrations and weights per m2 . The model was calibrated on 24 crop situations in 2012 and evaluated independently on 50 other situations (3 years) with contrasted genotypes and environments. Global trends were well reproduced for all "source" and "sink" components but most variables tended to be overestimated. The main indicators of model quality for predicting OC were: RMSE = 6.1 (%), efficiency = 0.97, R2 = 0.94 and Bias = -0.06 (%). A sensitivity analysis suggested us to reduce the number of parameters, better describe photosynthesis and N uptake processes, and improve the parameterization of genotype and nitrogen effects in order to decrease the prediction error and provide a relevant tool for OC prediction.

Given the diversification of oilseed-based products, sunflower is a competitive crop for obtaining high oil and protein concentrations; however, both are subject to genotypic and environmental variability. We analyzed individual and interaction effects of nitrogen (N), plant density (D) and genotype (G) in a 2-year field experiment. A set of “sink” (oil, protein, and hull concentrations and quantities) and “source” (leaf area duration, nitrogen uptake, nitrogen and biomass remobilizations) indicators were measured at harvest in a split-split-plot design with contrasting nitrogen (N+: 150 kg ha−1 ; N−: no fertilization), plant density (D1: 3 and D2: 4.5 plants m−2 ) and genotype (cv. LG5451HO in 2011, cv. Olledy in 2012 and cv. Kerbel in both years) treatments. We found that nitrogen had a significant positive effect on protein con- centration and plant density had a positive effect on nitrogen uptake after flowering. Oil concentration was not related to oil weight but was related to plant dry matter at flowering and biomass remobilization. Protein concentration was related to protein weight and nitrogen nutrition index at flowering and to nitrogen uptake and leaf area duration after flowering. Significant interaction effects were identified on sink (N × D, D × G) and source (N × G) indicators in the 2012 experiment, which was only partly explained by differences in initial states at flowering. In this study, the genotype that maximized oil concentration depended on nitrogen and plant density conditions, while the genotype that maximized protein concen- tration was the same regardless of cropping conditions. We highlight the importance of analyzing effects of determining factors on oil accumulation during grain filling.

Santoso BB, Budianto A, Aryana IGPM. 2012. Seed viability of Jatropha curcas in different fruit maturity stages after storage. Nusantara Bioscience 4: 113-117. The effect of fruit maturity stages and seed storage period to seed viability were investigated. Seed samples of West Lombok, West Nusa Tenggara genotype of Jatropha curcas were collected from standing two year old trees at experimental field. The seed samples obtained were in four different stages of fruit maturity involving early maturity (green fruit), physiological maturity (yellow fruit), over maturity (brownies fruit), and senescence (black-dry fruit). The results showed that fruit maturity had an influence as well storage period on the seed viability of Jatropha curcas. The best fruit maturity stage for seed viability including seed oil content was yellow fruit and brownies fruit. For germination to be maintained or preserved, seeds could be stored in the ambient room storage for at least five months. For the purpose of oil extraction, seed should preferably be stored maximum not more than four months under ambient room conditions.

Evaluation of Jatropha curcas germplasm comprising seven accessions indicated a wide range of variability in vegetative growth and other qualitative attributes. These characteristics could be harnessed in future improvement programme of Jatropha curcas. Seed yield/plant had a positive and significant correlation with number of branches/plant, oil yield, plant spread (r=0.806, 0.802, 0.782), plant spread had a highest correlation with plant height (r=0.840). The seeds analyzed for proximate composition, fatty acid and physiochemical characteristics revealed that fiber and ash content in seed flour were high (16.5% and 4.35%). Oil content varied from 24.5% to 37.9%. The lower value of the viscosity suggests it as diesel oil. Accession JC006 could be an alternative source of linoleic acid (51%) while the accession JC001 could be a source for oleic acid (48%) and linoleic acid 42.4%. Stearic acid was highest in accession JC003 (42.9%). This evaluation has helped to identify cultivar with specific yield and vegetative growth features. Among all the seven accession evaluated accession JC007 is found to be promising which could be taken as productive genotype for commercial exploitation. (C) 2011 SAAB. Published by Elsevier B.V. All rights reserved.

The objective of this study was the evaluation of NS sunflower hybrids on the basis of the results of seed yield, seed oil content and oil yield obtained in a network of small-plot trials in Vojvodina and central Serbia in 2010, as well as recommendations for the sowing season 2011. Seed yield, seed oil content and oil yield were significantly different in small-plot trials in the investigated regions. In Vojvodina, the highest average seed yield was produced by Duško (3.08 t ha-1), Sremac (2.98 t ha-1), Orfej (2.97 t ha-1) Velja (2.93 t ha-1) and NS-H-111 (2.92 t ha-1). In the region of central Serbia, the highest seed yield was achieved by the hybrids NS-H-111 (2.97 t ha-1) and Duško (2.87 t ha-1). Hybrid Baća showed the highest average seed oil content both in the region of Vojvodina (48.54%) and central Serbia (48.80%). The highest average oil yield (over 1.30 t ha-1) was produced by Duško, Bačvanin and NS-H-111 in the Vojvodina region, and in central Serbia oil yield (over 1.30 t ha-1) by NS-H-111, Oskar and Novosađanin. In the three-year trials in Vojvodina four hybrids (Duško, Sremac, Velja and NS-H-111) showed seed yield over general mean. The highest seed yield was reached by hybrid Duško (3.54 t ha-1). Cilj istraživanja je bio da se ocene NS hibridi suncokreta na osnovu rezultata koje su ostvarili za prinos semena, sadržaj ulja u semenu i prinos ulja u mreži mikro-ogleda u Vojvodini i centralnoj Srbiji tokom 2010. godine kao i da se da preporuka sortimenta za 2011. U mikro-ogledima je ispitivano 13 hibrida na 10 lokaliteta u Vojvodini i 3 u centralnoj Srbiji. Prinos semena, sadržaj ulja u semenu i prinos ulja su se značajno razlikovali u mreži mikro-ogleda u ispitivanim regionima. U Vojvodini, najveći prosečan prinos semena ostvarili su hibridi Duško (3,08 t ha-1), Sremac (2,98 t ha-1) Orfej (2,97 t ha-1), Velja (2,93 t ha-1) i NS-H-111 (2,92 t ha-1). U regionu centralne Srbije najviši prosečan prinos semena su postigli NS-H-111 (2,94 t ha-1) i Duško (2,87 t ha-1). Najveći prosečan sadržaj ulja u semenu ostvario je hibrid Baća, kako u regionu Vojvodine (48,54%) tako i u regionu centralne Srbije (48,80%). Najveći prosečan prinos ulja (preko 1,30 t ha-1) u regionu Vojvodine postigli su Duško, Bačvanin i NS-H-111, a u centralnoj Srbiji najveći prosečan prinos ulja (preko 1,30 t ha-1) ostvarili su hibridi NS-H-111, Oskar i Novosađanin. Na osnovu rezultata trogodišnjih ispitivanja u Vojvodini, četiri hibrida (Duško, Sremac, Velja i NS-H-111) su dali prinos semena iznad opšteg proseka. Najveći prosečan prinos semena za tri godine postigao je hibrid Duško (3,54 t ha-1).

Contact: berville@supagro.inra.fr; The genetic base of sunflower elite lines is very narrow, due to many years of selection and breeding. To broaden the genetic diversity of the cultivated sunflower, in 1995 73 wild sunflower populations were crossed with 3 cultivated lines (Testers), and 219 hybrid offspring's were evaluated in the field. GCA and SCA effects were computed suggesting for all traits a genetic potential for improvement through selection. Study of the hybrids revealed that the wild accessions bear different genetic abilities to combine with the testers for traits of morphological architecture, phenology and yield (seed weight and seed oil). The variance due to GCA and SCA showed that gene action was additive for days to flowering, branching and plant height. Genotypes derived from the same geographic origin may have either good or poor general combing ability. The correlation between GCA and per se genotype performance was positive for all traits except for seed oil content. This was the first attempt to evaluate wild-cultivated hybrids in sunflower on a large scale and will be the starting point for the management of hybrid Helianthus annuus populations for breeding. GCA and SCA estimations will facilitate the definition of strategies to manage and exploit the natural diversity for this crop

There is an increasingly demand for alternative vegetable oils sources. Over the last decade there has been fast growing interest in Moringa oleifera Lam., particularly due to its high seed oil yield (30–40%), while other Moringa species with similar potentialities are reducing their representativeness worldwide. This review reinforces the interesting composition of Moringa oil, rich in oleic acid and highly resistant to oxidation, for industrial purposes, and shows that other Moringa species could also be exploited for similar purposes. In particular, Moringa peregrina (Forssk.) Fiori has an interesting oil yield and higher resistance to pest and diseases, and Moringa stenopetala (Bak. f.) Cuf. is highlighted for its increased resistance to adverse climate conditions, of potential interest in a climate change scenario. Exploring adapted varieties or producing interspecies hybrids can create added value to these less explored species, while renewing attention to endangered species. Moringa seed oil can be extracted by conventional methods or using physical methods (pressing), creating diverse products from a compositional perspective, able to serve both the biodiesel and food industries.

High temperature enhances the oleic acid content in the oil of normal cultivars but conflicting results are reported on temperature effects on oleic acid content in HO cultivars: either no effect or an increase in oleic acid content with temperature. To investigate the effects of temperature on HO genotypes under natural field conditions, a three-year field trial was conducted using two sowing dates and three HO genotypes (two inbred lines and one hybrid). To compare our results with previous works, growing degree-days (GDD) were computed (base temperature=6°C). GDD accumulated during the “flowering – 25 days after flowering” period influenced fatty acid composition of seed. Oleic and linoleic acid contents were affected by accumulated GDD in two HO genotypes (one inbred line and the hybrid). There was an increase of about 3% in oleic acid content as response to more high GDD accumulated. Their content was not modified by GDD in the other inbred line. There was a genotype×environment interaction that we suppose depending on modifier genes. These genetic factors affected oleic acid content. This indicated the importance of breeding targeted to select hybrids with a stable oleic acid content and higher than 90%. Saturated fatty acids (palmitic and stearic) were also influenced by temperature, and there was genetic variability among genotypes.

This study was carried out to determination of some plant characteristics of Crambe genotype under Ankara conditions in the research and experimental fields of the Research Center for the Field Crops in 2013. In this study were used 82 genotypes of Crambe (Crambe hispanica subsp. abyssinica) which obtained from The USA Gene Bank. The number of days remaining in the rosette, 1000 seed weight (g), seed yield per plant (g), seed oil content (%) and fatty acid composition (%) of Crambe genotypes. According to the results obtained from this study; duration of the rosette stage 41 days, 1000 seed weight 6,6 g, seed yield per plant 2,3 g, seed oil content 13,4%, erusic acid content 54%, oleic acid content 14,35%, linoleic acid content 9,41%, linolenic acid content 7,59% were measured in Crambe genotypes., Bu çalışma; Crambe genotiplerinin bazı bitkisel özelliklerin belirlemesi amacıyla Ankara koşullarında Tarla Bitkileri Merkez Araştırma Enstitüsü Müdürlüğü’nün Araştırma ve Uygulama tarlasında 2013 yılında yürütülmüştür. Bu çalışmada materyal olarak ABD Ulusal Gen Bankası’ndan temin edilen 82 adet Crambe (Crambe hispanica subsp. abyssinica) genotipinden elde edilen veriler kullanılmıştır. Crambe bitkisinde, rozette kalma gün sayısı, bin tohum ağırlığı (g), bitki başına tohum verimi (g/bitki), tohumda yağ oranı (%) ve sabit yağ asitleri bileşimi (%) belirlenmiştir. Araştırma sonuçlarına göre sapa kalkma gün sayısı 41 gün, bin dane ağırlığı 6,6g, bitki başına tohum verimi 2,3 g/bitki, tohumda yağ oranı %13,4, erüsik asit oranı %54, oleik asit oranı %14,35, linoleik asit oranı %9,41 ve linolenik asit oranı %7,59 olarak belirlenmiştir.

Background Although the seed oil content in canola is a crucial quality determining trait, the regulatory mechanisms of its formation are not fully discovered. This study compared the silique and seed physiological characteristics including fresh and dry weight, seed oil content, chlorophyll content, and carbohydrate content in a high oil content line (HOCL) and a low oil content line (LOCL) of canola derived from a recombinant inbred line in 2010, 2011, and 2012. The aim of the investigation is to uncover the physiological regulation of silique and seed developmental events on seed oil content in canola. Results On average, 83% and 86% of silique matter while 69% and 63% of seed matter was produced before 30 days after anthesis (DAA) in HOCL and LOCL, respectively, over three years. Furthermore, HOCL exhibited significantly higher fresh and dry matter at most developmental stages of siliques and seeds. From 20 DAA, lipids were deposited in the seed of HOCL significantly faster than that of LOCL, which was validated by transmission electron microscopy, showing that HOCL accumulates considerable more oil bodies in the seed cells. Markedly higher silique chlorophyll content was observed in HOCL consistently over the three consecutive years, implying a higher potential of photosynthetic capacity in siliques of HOCL. As a consequence, HOCL exhibited significantly higher content of fructose, glucose, sucrose, and starch mainly at 20 to 45 DAA, a key stage of seed lipid deposition. Moreover, seed sugar content was usually higher than silique indicating the importance of sugar transportation from siliques to seeds as substrate for lipid biosynthesis. The much lower silique cellulose content in HOCL was beneficial for lipid synthesis rather than consuming excessive carbohydrate for cell wall. Conclusions Superior physiological characteristics of siliques in HOCL showed advantage to produce more photosynthetic assimilates, which were highly correlated to seed oil contents. Electronic supplementary material The online version of this article (doi:10.1186/1999-3110-55-34) contains supplementary material, which is available to authorized users.

Ten accessions of wild Borago officinalis were collected during missions in the course of a research activity carried out on plants producing nutraceutical compounds. The aim was to identify populations that produce a higher content of γ-linolenic acid, as this compound has important therapeutic properties and has been used in medical tests to treat rheumatoid arthritis, eczema, and psoriasis with good therapeutical results. The present study reports on the characterization of both the polyunsaturated fatty acid composition and on genetic diversity estimated by means of AFLP markers in several B. officinalis accessions collected in Southern Italy and grown in isolation by means of screen houses specifically designed for each single population. Polyunsaturated fatty acid were found in different amounts in all investigated accessions. The populations were very variable at the molecular level, and the analysis of relationships based on AFLP data, showed that similarity based on Jaccard’s index ranged between 0.330 and 0.742. Our investigations allowed us to identify a population that may be considered as a good source of GLA.

A genomic sequence encoding a polypeptide with 91% sequence identity to the Lesquerella fendleri bifunctional oleate 12-hydroxylase:desaturase was amplified by PCR from Lesquerella lindheimeri. Expression of the gene in the yeast Saccharomyces cerevisiae resulted in the synthesis of ricinoleic acid and very low levels of di-unsaturated fatty acids. Comparison of the amino acid sequences of the L. lindheimeri and castor bean oleate 12-hydroxylase enzymes to those of the L. fendleri bifunctional oleate 12-hydroxylase:desaturase and oleate 12-desaturase enzymes from 32 diverse species identified a single amino acid (M295) that was conserved in the hydroxylases and different but also conserved in the desaturases and the bifunctional enzyme. Site-directed mutagenesis indicated that this residue was most likely not involved in determining the catalytic outcome of the hydroxylation/desaturation reaction. Transformation of an Arabidopsis fad2/fae1 mutant line with the L. lindheimeri hydroxylase gave further evidence that this enzyme, like the castor oleate12-hydroxylase, isprimarilya fattyacid hydroxylase and should notbe considered bifunctional. Total hydroxyfatty acid contentof up to 18% of seed fatty acids was measured in homozygous transformants. Lines with the highest hydroxy fatty acid content showed significant reduction in total oil content. Crown Copyright # 2007 Published by Elsevier Ireland Ltd. All rights reserved.

The study was aimed to examine the changes in seed vigor and oil content in different genotypes of maize, soybean and sunflower over four years (2002-2006) in two type storage conditions differed in terms of air temperature and humidity: 25 C/75% and 12 C/60%, respectively. Affected by storage longevity, on an average, seed vigor decreased for 18, 7% in maize and for 57, 1% in both soybean and sunflower, respectively. Seed oil content decreased for 1, 12% in maize, 2, 27% in soybean and 12, 05% in sunflower. Differences in seed vigor and oil content affected by storage longevity were significant among tested crops and genotypes into crop. Storage longevity was negatively associated with seed vigor and oil content. At storage conditions by 12 C/60%, decline of seed vigor was less for 17% (maize), for 24% (sunflower, soybean)and decreasing of seed oil content was less for 0, 87% (maize, 0, 91% (soybean)and 2, 27% (sunflower) than in storage conditions by 25 C/75%. In summary, the lowest seed quality losses were in maize, then in soybean and the highest losses were in sunflower. Decreasing seed quality losses is possible with providing suitable storage conditions, particularly for soybean and sunflower.

The study aimed to examine the changes in seed vigor and oil content in different genotypes of maize, soybean and sunflower over three years (2002-2005) in two type storage conditions differed in terms of air temperature and humidity: 25°C/75% and 12°C/60%, respectively. Affected by storage longevity, on an average, seed vigor decreased by 13.5% in maize and by 26.5% in both soybean and sunflower, respectively. Seed oil content decreased by 0.58% in maize, 1.68% in soybean and 8.04% in sunflower. Differences in seed vigor and oil content affected by storage longevity were significant among tested crops and genotypes into crop. Storage longevity was negatively associated with seed vigor and oil content. At storage conditions by 12°C/60%, decline of seed vigor was less by 7% (maize), by 11% (sunflower, soybean) and decreasing of seed oil content was less for 0.25% (maize), 0.53% (soybean) and 1.75% (sunflower) than in storage conditions by 25°C/75%. In summary, the lowest seed quality losses were in maize, followed by soybean and the highest ones in sunflower. Decreasing seed quality losses is possible with providing suitable storage conditions, particularly for soybean and sunflower., Istraživanjem je utvrđen utjecaj uvjeta skladištenja dorađenog nezaprašenog sjemena hibrida kukuruza i suncokreta te sorata soje na vigor i sadržaj ulja nakon skladištenja od 36 mjeseci (2002.-2005.) u dva tipa skladišta različite temperature i vlage zraka (S1: 25°C/75% i S2 12°C/60%). Nakon skaldištenja, vigor sjemena je umanjen za 13,5% kod kukuruza, 26,5% kod soje i 27,1% kod suncokreta. Sadržaj ulja u zrnu je umanjen za 0,58% kod kukuruza, 1,68% kod soje i za 8,04% kod suncokreta. Duljinom skladištenja umanjen je vigor i sadržaj ulja. U uvjetima skladišta S1 je manje umanjenje vigora za 7% (kukuruz), 11% (suncokret, soja), kao i manje umanjenje sadržaja ulja za 0,25% (kukuruz), 0,53% (soja) i 1.75% (suncokret) u odnosu na uvjete skladištenja u skladištu S2. Kakvoća sjemena je tijekom skladištenja ovisna o vrsti kultivara, genotipu i uvjetima skladištenja.

Lunaria annua is a biennial cruciferous oil seed crop. The seeds contain 30–35% oil, which consists of 67% long chain fatty acids (44% erucic acid, C22:1, and 23% nervonic acid, C24:1). The oil is suitable as lubricant. In addition, recent developments indicate that nervonic acid may be used as raw material for the production of a medicine against multiple sclerosis. The biennial character of Lunaria is a main constraint for an economically feasible production of Lunaria oil. The crop has to be sown early in the summer to achieve vigorous plant development required for vernalization during the winter. It would be a great advance when Lunaria could be sown later in the summer after an early harvested crop. From 1993, breeding research in Lunaria has been performed at CPRO-DLO, Wageningen, The Netherlands. A collection of 76 accessions was maintained and evaluated for agronomic performance. In 1995, a selection of 24 accessions were sown at four sowing dates, from end June until end of August and in 1996, 12 promising accessions were sown again at 15 and 30 July. Three accessions showed suitability for delayed sowing until beginning of August. Delay in sowing time caused also delay of flowering and seed ripening. Seed yield amounted to 1200 kg/ha in 1996 and 1700 kg/ha in 1997. Seed oil content varied from 30–38%. Severe infection of Albugo candida and Alternaria occurred and might have reduced seed yield in both years. Most accessions sustained severe winter frost of−17°C very well. It is concluded that within the evaluated gene pool promising variation is available to select for ability for late sowing, to improve the disease resistance and to increase seed yield and seed oil content.

Objectives: In this study, were investigated fatty acids composition of soybean oil cultivars. Material and Methods: Soybean oil from ten cultivars of the Agricultural Institute of Osijek (Vratarić et al., 1994) from three localities in 1996 year, were extracted with diethyl ether containing butilated hidroxytoluene (Yoshida and Kajimoto, 1989). Fatty acids were determinate by GC standard method (ISO, 1977).Results and discussion: Oil content in soybean cultivars ranged from 19.98 to 20.69%. The amounts of saturated fatty acids in soybean oil cultivars ranged: myristic (0.43-0.78%), palmitic (10.96-11.80%), stearic (3.33-3.92%), arachidic (0.26-0.27%), behenic (0.30-0.31%), and unsaturated: oleic (18.77-22.02%), linoleic (52.98-54.55%) and linolenic (8.64-9.88%). There was no significant difference unsaturated fatty acids content except miristic acid, among localities. Unsaturated fatty acids varied significantly between localities. Conclusion and Perspectives: The experimental results presented here may be useful for the development of grain quality of soybean cultivars. Bibliography: ISO standard (1977), ISO/TC 34/SC, 3, 554; Konishi, H., W.F., Neff and T.L. Mounts, (1993), J. Chromatogr. 629, 237.; Vratarić M., A. Sudarić, M. Janković, (1994), Prehrambeno-tehnol.biotehnol.rev. 32, 157.; Wilcox J.R. (1984), in Proceeding of the World Soybean Research III Edition by Shibles R. 380.

L'infection par le champignon phytopathogene entraine une diminution du poids de 1000 akenes, de leur teneur en fibres et en huile, une augmentation de leur teneur en proteines et des modifications significatives de la teneur en differents acides gras de l'huile

Traditional medicines of plant origin are used by world’s large population. Economic development including eradication of poverty in developing countries like, India or other countries of the world required increase in agricultural productivity. Bio fertilizers plays a very important role in modern agriculture, in achieving higher productions in Agriculture at lower input costs using biotechnological innovations at large. An endophytic symbiotic fungus, Piriformospora indica isolated from desert soils of Rajasthan, India promotes growth as well as important ingredients of the medicinal as well as economically important plants by forming association with roots of various plants and it has been established as biofertilizer, bioprotector, immunoregulator and agent for biological hardening of tissue culture raised plants. P. indica tremendously improves the growth and overall biomass production of adiverse host including legumes, medicinal and economically important plants. Pronounced growth promotional effect was seen with terrestrial orchids. P. indica was able to colonize the rhizoids of liverwort and the thalli failed to grow under in situ conditions in the absence of this fungus. The fungus also provided protection when inoculated into the tissue culture raised plants by overcoming the ‘transient transplant shock’ on transfer to the field and renders almost 100% survival on transplant. P. indica cell biomass which has potential for promoting growth of many plants (above 145) has been documented so far which include plants such as Centella asiatica, Coriandrum sativum, Artimisia annua, Spilanthus calva, Arabidopsis thalina, Cajanus cajan, Arachis hypogea, Mimosa pudica, Cicer arietinum, Allium cepa, Hordeum vulgare, Zea mays, Saccharum officinarum, Withania somnifera, Solanum lysopersicum, etc. However, impact of P. indica culture filtrate on plant growth promotion has been studied only in few plants. Important medicinal plants and plants of economic importance on which effect of culture filtrate of P. indica has been studied include plants such as Z. mays, Bacopa monniera, Nicotiana tabaccum, Azadiracta indica, Aristolochia elegans, Helianthus annus and Solanum melongena. P. indica, a root colonizing fungus which is cultivable axenically, uniquely possesses multifunctional properties such as plant promoter, plant protector, resistance against heavy metals, bio herbicide, immune-modulator, resistance against temperature, salt and stress tolerance as bio fertilizer and tool for basic research. There are prospects that ingredients present in culture filtrate, that are stimulated and produced in response to ingredients of culture filtrate in plants, will be identified in future completely thereby opening more avenues of applications of P. indica. Many more properties and functions of P. indica cells and culture filtrate are expected to be known in future.Keywords: Helianthus annus, Piriformospora indica, seed oil content, culture filtrate, aristolochia, plant microbe interaction

Background Oil in the form of triacylglycerols (TAGs) is quantitatively the most important storage form of energy for eukaryotic cells. Diacylglycerol acyltransferase (DGAT) is considered the rate-limiting enzyme for TAG accumulation. Chlorella, a unicellular eukaryotic green alga, has attracted much attention as a potential feedstock for renewable energy production. However, the function of DGAT1 in Chlorella has not been reported. Results A full-length cDNA encoding a putative diacylglycerol acyltransferase 1 (DGAT1, EC 2.3.1.20) was obtained from Chlorella ellipsoidea. The 2,142 bp open reading frame of this cDNA, designated CeDGAT1, encodes a protein of 713 amino acids showing no more than 40% identity with DGAT1s of higher plants. Transcript analysis showed that the expression level of CeDGAT1 markedly increased under nitrogen starvation, which led to significant triacylglycerol (TAG) accumulation. CeDGAT1 activity was confirmed in the yeast quadruple mutant strain H1246 by restoring its ability to produce TAG. Upon expression of CeDGAT1, the total fatty acid content in wild-type yeast (INVSc1) increased by 142%, significantly higher than that transformed with DGAT1s from higher plants, including even the oil crop soybean. The over-expression of CeDGAT1 under the NOS promoter in wild-type Arabidopsis thaliana and Brassica napus var. Westar significantly increased the oil content by 8–37% and 12–18% and the average 1,000-seed weight by 9–15% and 6–29%, respectively, but did not alter the fatty acid composition of the seed oil. The net increase in the 1,000-seed total lipid content was up to 25–50% in both transgenic Arabidopsis and B. napus. Conclusions We identified a gene encoding DGAT1 in C. ellipsoidea and confirmed that it plays an important role in TAG accumulation. This is the first functional analysis of DGAT1 in Chlorella. This information is important for understanding lipid synthesis and accumulation in Chlorella and for genetic engineering to enhance oil production in microalgae and oil plants. Electronic supplementary material The online version of this article (doi:10.1186/s12870-017-0995-5) contains supplementary material, which is available to authorized users.