Recombinant Inbred Lines Of Sunflower Research Articles

Создание и изучение рекомбинантных инбредных линий подсолнечника с различным содержанием олеиновой кислоты в масле семян

Создание и изучение рекомбинантных инбредных линий подсолнечника с различным содержанием олеиновой кислоты в масле семян

Genotypic Variability in Carbon Isotope Discrimination and Water Use Efficiency among Recombinant Inbred Lines of Sunflower (Helianthus annuus L.)

To evaluate genotypic variability in carbon isotope discrimination or CID and water use efficiency or WUE, recombinant inbred lines (RILs) population of sunflower ( Helianthus annuus L.) was used. Seventy eight sunflower RILs were grown in greenhouse and 100 sunflower RILs were grown under field condition, and measured some morphological and physiological traits including leaf area at flowering (LAf), net CO2 assimilation rate ( A ) and transpiration per day at flowering (Ef). WUE, called “potential” WUE (WUEp), was calculated as the ratio of assimilation potential (Ap) to transpiration per day at flowering (Ef) where Ap was derived from the multiplication of A with LAf. The CID was significantly varied among RILs and there was significant negative genetic correlation between CID and WUEp. Heritability of the CID was higher rather than the WUEp which reflected wide genetic variability of CID. The genetic correlation between CID and WUEp and the wide genotypic variability of CID indicated that CID can be proposed as an indicator to determine WUE in sunflower and open a way in understanding the genetic diversity of the RILs which could be used as a basic consideration before applying selection program in sunflower breeding.

Identification of quantitative trait loci for relative water content and chlorophyll concentration traits in recombinant inbred lines of sunflower (Helianthus annuus L.) under well-watered and water-stressed conditions

Identification of quantitative trait loci for relative water content and chlorophyll concentration traits in recombinant inbred lines of sunflower (Helianthus annuus L.) under well-watered and water-stressed conditions

Effect of drought stress on yield and yield components of some sunflower recombinant inbred lines

Nine sunflower inbred lines as listed in (table 3) were chosen for this study. The present work was planned to study effect of drought on yield and yield components of selected inbred lines of sunflower. The information will be important in developing sunflower cultivars tolerant to water stress. The experiment was conducted in a randomized complete block design (RCBD) under split plot arrangement with three replications. The main plots comprised of three treatments i.e. severe water stress, mild water stress and normal irrigation. In the normal condition, plants were watered daily throughout the cropping period, while in the mild and severe stress condition; water stresses was created from R4 and R6 stage, respectively. Highly significant differences observed between stress treatment for Head diameter and stem diameter. While for seed yield and 1000 seed weight exhibited significant differences. Mean squares of different traits under drought and normal irrigation conditions revealed highly significant differences between sunflower inbred lines for all the traits studied. B329, R56 and B147 were less affected under water stress conditions as compared to other lines for seed yield per plant and head diameter. Inbred line B343 for number of seed per plant and inbred line R50 for 1000 seed weight were less affected too. Inbred lines B329 and R56 proved more drought tolerant for stem diameter and plant height. Principle component analyses were done in all three treatments. There were two principle components in each PCA. Thefirst PC (PC1) had high positive correlation with all the traits studied except number of seed per plant. The second (PC2) mostly had high positive correlation with number of seed per plant. The lines B329, R56, B343, R50 and R26 had the least variance in these three treatments. In other word, they were drought tolerant in this experiment but only B329 and R56 had high performance compare with other lines.

Effective selection criteria for screening drought tolerant recombinant inbred lines of sunflower

In this study, seventy two sunflower recombinant inbred lines were tested for their yielding ability under both water-stressed and well-watered states. The inbred lines were evaluated in a rectangular 8?9 lattice design with two replications in both well-watered and water-stressed conditions, separately. Eight drought tolerance indices including stability tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress susceptibility index (SSI), tolerance index (TOL), yield index (YI) and yield stability index (YSI) were calculated based on grain yield for every genotype. Results showed the highest values of mean productivity (MP) index, geometric mean productivity (GMP), yield index (YI), harmonic mean (HM) and stress tolerance index (STI) indices for ?C134a? inbred line and least values of stress susceptibility index (SSI) and tolerance (TOL) for C61 inbred line. According to correlation of indices with yield performance under both drought stress and non-stress states and principle component analysis, indices including HM, MP, GMP and STI could properly distinguish drought tolerant sunflower inbred lines with high yield performance under both states. Cluster analysis of inbred lines using Ys, Yp and eight indices, categorized them into four groups including 19, 6, 26 and 19 inbred lines.

Genetic dissection of tocopherol and phytosterol in recombinant inbred lines of sunflower through quantitative trait locus analysis and the candidate gene approach

Sunflower (Helianthus annuus L.) contains tocopherol, a non-enzymatic antioxidant known as lipid-soluble vitamin E, and phytosterol, with interesting properties, which can result in decreased risk of chronic diseases in humans and with several beneficial effects in plants. The genetic control of tocopherol and phytosterol content in a population of 123 recombinant inbred lines of sunflower was studied through quantitative trait loci (QTL) analysis using 190 simple sequence repeats and a gene-based linkage map. Seven experiments were conducted in different environments in France and Iran during 2007 and 2008. Each experiment consisted of three replications. Means over all environments were used for QTL mapping. Five QTL for total tocopherol content on linkage groups 1, 8, 10 and 14 accounted for 45% of phenotypic variation, whereas four QTL for total phytosterol content on linkage groups 1, 2, 16 and 17 explained 27% of the phenotypic variation. GST, PAT2, SFH3 and POD genes showed co-localization with QTL for total phytosterol content. SMT2 is also mapped on linkage group 17 near the QTL of total phytosterol content. Four candidate genes, VTE4, HPPD, GST and Droug1, exhibited co-localization with QTL for total tocopherol content. The candidate genes associated with tocopherol and phytosterol, especially HPPD, VTE4 and SMT2, could be used for alternation of the tocopherol and phytosterol content of sunflower seeds through the development of functional markers.

QTL analysis of agronomic traits in recombinant inbred lines of sunflower under partial irrigation

The objective of the present research was to map QTLs associated with agronomic traits such as days from sowing to flowering, plant height, yield and leaf-related traits in a population of recombinant inbred lines (RILs) of sunflower (Helianthus annuus). Two field experiments were conducted with well-irrigated and partially irrigated conditions in randomized complete block design with three replications. A map with 304 AFLP and 191 SSR markers with a mean density of 1 marker per 3.7 cM was used to identify QTLs related to the studied traits. The difference among RILs was significant for all studied traits in both conditions. Three to seven QTLs were found for each studied trait in both conditions. The percentage of phenotypic variance (R2) explained by QTLs ranged from 4 to 49%. Three to six QTLs were found for each yield-related trait in both conditions. The most important QTL for grain yield per plant on linkage group 13 (GYP-P-13-1) under partial-irrigated condition controls 49% of phenotypic variance (R2). The most important QTL for 1,000-grain weight (TGW-P-11-1) was identified on linkage group 11. Favorable alleles for this QTL come from RHA266. The major QTL for days from sowing to flowering (DSF-P-14-1) were observed on linkage group 14 and explained 38% of the phenotypic variance. The positive alleles for this QTL come from RHA266. The major QTL for HD (HD-P-13-1) was also identified on linkage group 13 and explained 37% of the phenotypic variance. Both parents (PAC2 and RHA266) contributed to QTLs controlling leaf-related traits in both conditions. Common QTL for leaf area at flowering (LAF-P-12-1, LAF-W-12-1) was detected in linkage group 12. The results emphasise the importance of the role of linkage groups 2, 10 and 13 for studied traits. Genomic regions on the linkage groups 9 and 12 are specific for QTLs of leaf-related traits in sunflower.

QTL analysis of yield‐related traits in sunflower under different water treatments

AbstractA set of sunflower recombinant inbred lines (RILs) was used to study agronomical traits under greenhouse and field conditions each with two water treatments and three replications. The difference among RILs was significant for all the traits studied in all conditions; and water treatment × RILs interaction was also observed for most of the traits in both field and greenhouse conditions. Because of the low rate of drought stress, this part of field data are not informative. Several quantitative trait loci (QTLs) were identified for yield‐related traits with the percentage of phenotypic variance explained by QTLs (R2) ranging from 4% to 40%. Several QTLs for grain yield per plant (GYP) under four water treatments were identified on different linkage groups, among which two were specific to a single treatment (GYPN.4.1, GYPI.7.1). Three QTLs for GYP were overlapped with several QTLs for drought‐adaptative traits detected in our previous study (Poormohammad Kiani et al. 2007b). The whole results do highlight interesting genomic regions for marker‐based breeding programmes for drought tolerance in sunflower.

QTL mapping of seed-quality traits in sunflower recombinant inbred lines under different water regimes

The objectives of the present research were to determine the effects of water stress on seed-quality traits and to map QTLs controlling the studied traits under two different water treatments in a population of sunflower recombinant inbred lines (RILs). Two experiments were conducted in greenhouse and field conditions, each with well-watered and water-stressed treatments. The experiments consisted of a split-plot design (water treatment and RIL) with three blocks. Analyses of variance showed significant variation among genotypes, and a water treatment x genotype interaction was also observed for most of the traits. Two to 15 QTLs were found, depending on trait and growth conditions, and the percentage of phenotypic variance explained by the QTLs ranged from 5% to 31%. Several QTLs for oil content overlapped with QTLs for palmitic and stearic acid contents in all four conditions. An overlapping region on linkage group 3 (QTLs 2.OC.3.1 and 4.SA.3.1) was linked to an SSR marker (ORS657). A principal component analysis was performed on four fatty acid traits. Two principal components, P1 and P2, were used for QTL analysis. This method improved the ability to identify chromosomal regions affecting the fatty acids. We also detected the principal-component QTLs that did not overlap with the fatty acid QTLs. The results highlight genomic regions of interest in marker-based breeding programmes for increasing oil content in sunflower.

Somatic embryogenesis from thin epidermal layers in sunflower and chromosomal regions controlling the response

Somatic embryogenesis of sunflower recombinant inbred lines from the cross ‘PAC-2’ × ‘RHA-266’ was investigated and three QTLs were resolved for the number of embryogenic explants per 100 explants cultured. In order to increase the resolution in our mapping of the QTL regions, two consistently highly embryogenic lines ‘LR35’ and ‘C40’ that have alleles with positive effects at all three loci were crossed to a poorly embryogenic line ‘C149’ having alleles with negative effects at these three QTLs. The genotypes of F2 plants of both crosses were determined using a large number of AFLP and some SSR markers and two linkage maps were constructed. Based on the marker profile at QTL regions, 16 F2 plants, 9 presenting QTLs expected to produce F3 families with high and 7 with low expected embryogenic responses, were selected and somatic embryogenesis of F3 families was studied. In 14 out of 16 cases the phenotype of F3 families agreed with the genotype of their respective F2 plants. Therefore, these three QTLs accounted for most of the embryogenic variations. This study enabled the localization of the QTL regions to much shorter intervals and the identification of four AFLP markers on linkage groups 5 and 13 closely linked to somatic embryogenesis potential.

Genetic analysis of plant water status and osmotic adjustment in recombinant inbred lines of sunflower under two water treatments

The goals of the present research were to develop an integrated and high density genetic-linkage map using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers on a population of 123 F9 recombinant inbred lines (RILs) and to identify QTLs involved in the genetic control of water status traits and osmotic adjustment under well-watered and water-stressed conditions. A map with 304 AFLP and 191 SSR markers with a mean density of one marker per 3.7 cM was constructed. Our physiological experiment consisted of a split-plot design with three blocks. The main plot consisted of water treatments (well-watered and water-stressed) and subplot contained 78 RILs and parental lines. Water deficit was induced in 45-day-old plants at stage near flower bud formation for a period of 12 days. After 12 days of differential watering, water status traits (leaf water potential, relative water content, turgor potential, osmotic potential and osmotic potential at full turgor) as well as osmotic adjustment (OA) were evaluated. The effects of water treatment, RIL and ‘RIL × water treatment’ were significant. QTL analysis showed that several putative genomic regions are involved in the total variation of water status traits under two water treatments. Among 24 QTLs detected under well-watered conditions, 5 (about 21%) were also detected in the water-stressed treatment. The percentage of phenotypic variance explained by the QTLs ranged from 6% to 29%. Among the eight QTLs detected for OA, four of them (50%) were co-located with the QTLs for turgor potential ( Ψ t) on linkage group 4 ( OA.4.1), with the QTL for osmotic potential at full turgor ( Ψ sFT) in well-watered RILs on linkage group 12 ( OA.12.2), and with QTLs of several traits on linkage group 5 ( OA.5.1 and OA.5.2). The four other QTLs for OA (50%) were very specific. The major QTL for OA on linkage group 5 accounted for 29% of the phenotypic variation, which is overlapped also with the QTLs for several water status traits. However, the QTLs were identified in greenhouse conditions and the usefulness of these QTLs for marker-assisted selection should therefore be evaluated under field conditions, and validated in other genetic backgrounds.

Genotypic variation and identification of QTLs for agronomic traits, using AFLP and SSR markers in RILs of sunflower (Helianthus annuus L.).

A population of 77 recombinant inbred lines (RILs) were developed through single-seed descent from a cross between 'PAC-2' and 'RHA-266'. Seeds of the above-mentioned RILs and their parents were planted in the field in a randomised complete block design with two replications. Genetic control for some agronomical traits-sowing-to-flowering date, plant height, stem diameter (SD), head diameter (HD), grain weight per plant, 1,000-grain weight (TGW) and the percentage of oil in grains-were measured for RILs and their parents. Genetic variability was observed among 77 RILs for all traits studied. Transgressive segregation occurred for some traits, and the comparison between 10% of selected RILs with the best parent showed significant difference for SD and HD as well as for TGW. A set of 123 RILs from the same cross, including the 77 above-mentioned RILs and their two parents, were screened with 409 AFLP and SSR markers, and a linkage map was constructed based on 367 markers. Several QTLs associated with the studied traits were identified. The effects of each QTL are moderate, ranging from 7% to 37%, but a high percentage of phenotypic variance is explained when considering all the covariants (TR2 mean around 80% in each trait). Although the detected regions need to be more precisely mapped, the information obtained should help in marker-assisted selection.

Analysis of resistance criteria of sunflower recombined inbred lines against Orobanche cumana Wallr.

Orobanche cumana a root parasitic angiosperm causes severe yield losses in sunflower in the Mediterranean regions. Up to now no control strategies are field effective and the only way to produce sunflower safely is the use of resistant genotypes. Broomrape resistance is however poorly understood and “new races” of the parasite evolve rapidly to overcome the resistance of newly introduced sunflower lines. Ninety sunflower Recombinant Inbred Lines (RIL, in F6) derived from a cross between a resistant Helianthus, LR1 (H. annuus×H. debilis debilis (resistant wild species)), and the susceptible line, HA89, were screened in hydroponic co-culture with Orobanche. During this study large variations of three resistance criteria, were observed among the RILs. These criteria were: broomrape seed germination induction by RIL root exudates, broomrape necrosis and the growth of broomrape to advanced development stages. The last two recorded parameters appear to be independent. There was considerable variation in the characters among screened inbred lines. This suggests that polygenic resistance could occur in LR1 derived RILs. Mapping of molecular markers of the resistance mechanisms as well as field trials of RILs are currently in progress.

Testing two isolates of diaporthe/phomopsis helianthi in a population of sunflower recombinant inbred lines

Development of new, more aggressive isolates of Phomopsis helianthi in Serbia and Montenegro has been investigated. Two isolates of Phomopsis helianthi, Yu 4 and Yu 12, had been found on the stem of NS-H-45, a highly tolerant sunflower hybrid. The isolate Yu 4 was isolated in the northern part of the Vojvodina Province, a region where Phomopsis typically occurs. The isolate Yu 12 comes from the southern part of the Vojvodina Province, a region along the Danube River, which suffered an intensive outbreak of Phomopsis in 1997. A preliminary study of the isolates showed that these two isolates were significantly different for radial growth in Petri dish. A test was thus made with recombinant inbred lines in the F₉ generation developed from the cross of LR- 4-17 (inbred line with high tolerance to Phomopsis) and HA-89 (susceptible inbred line). Experiments were conducted in the greenhouse, inoculating plant leaf tips with the mycelium of the fungus. The test showed that there were no significant differences between the two isolates, Yu 4 and Yu 12. It was concluded that the intensive attack recorded in 1997 along the Danube River occurred due to exceptionally favorable environmental conditions for the development of the disease.

Analysis of resistance criteria of sunflower recombined inbred lines against Orobanche cumana Wallr.

Orobanche cumana a root parasitic angiosperm causes severe yield losses in sunflower in the Mediterranean regions. Up to now no control strategies are field effective and the only way to produce sunflower safely is the use of resistant genotypes. Broomrape resistance is however poorly understood and “new races” of the parasite evolve rapidly to overcome the resistance of newly introduced sunflower lines. Ninety sunflower Recombinant Inbred Lines (RIL, in F6) derived from a cross between a resistant Helianthus, LR1 ( H. annuus× H. debilis debilis (resistant wild species)), and the susceptible line, HA89, were screened in hydroponic co-culture with Orobanche. During this study large variations of three resistance criteria, were observed among the RILs. These criteria were: broomrape seed germination induction by RIL root exudates, broomrape necrosis and the growth of broomrape to advanced development stages. The last two recorded parameters appear to be independent. There was considerable variation in the characters among screened inbred lines. This suggests that polygenic resistance could occur in LR1 derived RILs. Mapping of molecular markers of the resistance mechanisms as well as field trials of RILs are currently in progress.

Combined mapping of DALP and AFLP markers in cultivated sunflower using F9 recombinant inbred lines.

A genetic map was constructed with specific PCRs, DALPs and AFLPs using F8-generation sunflower recombinant inbred lines. RI lines generated from a F2 population of one cross between the two cultivated inbred lines HA89 (maintainer for Pet1 CMS) and LR4 (restorer for Pet1 CMS) were used. A total of 305 markers were located using seven sPCR, 64 DALP and 301 AFLP loci. They were generated with one, seven and 14 primer pairs, respectively. The map construction consisted of a two-step strategy using 6 and 3.1 LOD scores revealed by a simulation file. Mapped markers were assembled into 18 linkage groups covering 2,168.6 cM with an average of 6.1 cM. The distribution of DALPs and AFLPs revealed that both markers tagged different regions to enable covering most of the sunflower genome. This leads to the longest map published so far for sunflower.

Genetic control of in vitro‐organogenesis in recombinant inbred lines of sunflower (Helianthus annuus L.)

AbstractNinety‐three recombinant inbred lines (F8) of sunflower developed by the single‐seed descent method from the cross ‘PAC‐2 × RHA‐266’ were used to screen their regenerability by organogenesis. The experiment was designed in randomized complete blocks with three replications. Each replication consisted of 10 Petri dishes with four explants. Cotyledons were excised from 2‐day‐old seedlings. Each cotyledon was divided into two pieces (four explants), which were incubated in solid regeneration medium consisting of full‐strength Murashige and Skoog medium modified by adding hormones. A high genotypic variability for organogenesis parameters between genotypes was observed in this study. The difference between all recombinant F8 lines and their parents was not significant, showing that the 93 inbred lines used in this experiment are representative of the total possible recombinant lines from the cross ‘PAC‐2 × RHA‐266′. These F8 lines were not consciously selected for any trait; therefore, they represent a random set of lines segregating for the organogenesis parameters, as well as for other traits which could be important for breeding.

Influence of genotype and gelling agents on in vitro regeneration by organogenesis in sunflower

Fourteen recombinant inbred lines of sunflower (Helianthus annuus L.) and their parents (PAC-2 and RHA-266) were tested for their organogenesis ability. Seeds were surface sterilized and germinated on hormone free half strength MS basal medium containing 10 g l-1 sucrose solidified with five different gelling agents: Phytagar (Gibco laboratoires) 3 g l-1, Phytagel (Sigma) 3 g l-1, Agarose (Sigma) 5 g l-1, Arcagel (Sigma) 4 g l-1 and Agar-Agar (Fisher France) 7 g l-1. Cotyledons from 2-day-old seedlings were split in half and the four explants of each seed were cultived in 55 mm diameter petri dishes containing 10 ml of MS medium supplemented with 50 μM KNO3, 1 μM myo-inositol, 5 μM casein hydrolysate, 4.4 μM of BA and 5.4 μM of NAA solidified with the same gelling agents. The experimental design was a randomized complete block with 3 replications. A replicate for each genotype consisted of ten petri dishes containing four explants. The statistical analysis showed significant differences among genotypes and gelling agents. Of the fourteen recombinant inbred lines tested `C93' presented the highest values for all regeneration traits in the five different media and it was better than the best parent. Agarose and Agar-Agar were more better than other gelling agents for shoot induction.