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The work aimed to assess the restoration of metal-contaminated soil pH and EC and impacts on Cd accumulation in plants Helianthus annuus (Sunflower) through tea waste in a natural environment. Various doses of Cd metal treatment (1–5 ppm) were provided to the soil with two sets of organic matter (tea waste) in a dry and wet state. The soil and plants were analyzed using analytical procedures like AAS, SEM and EDS, while pH and EC were measured through pH and conductivity meter. The mitigating effect of tea waste was observed on the pH (6.2–6.9) and EC of the soil, which was reflected by the healthy growth of the plants. It was established that the movement of the Cd was successfully controlled with the restoration of essential nutrient elements in different parts of plants. It was strongly related to recovered soil pH and EC in two sets of tested H. annuus plant species. The healthy growth of the plants showed that tea waste acts as a safe, harmless and sound remediator of soil, which enhances the soil nutrient ionic activity from soil to roots of the plants in the presence of the Cd metal, effective for the use of agriculture purposes. [ABSTRACT FROM AUTHOR]

The sunflower (Helianthus annuus L.) is a fundamental oil-yielding culture for Bulgaria and the world and thus, special attention is paid to it. Various selection methods have been used over the years and as a result of successful breeding programs new sunflower forms, lines (В/А and R) and hybrids (oil and confectionery type) were created in Bulgaria. Some of these new forms have new plant architectonic, different vegetation periods, seeds with different sizes and coloration, high combining ability, resistance to diseases, the parasite Broomrape and some herbicides, high seed oil and fatty acid content, genes for restoration of fertility (Rf genes), and different types of cytoplasmic male sterility (CMS). [ABSTRACT FROM AUTHOR]

Cultivated sunflower (Helianthus annuus) is not typically considered to have a pleasant floral fragrance. In field production, seed yield is often limited by pollination services, particularly in the production of hybrid seed. Improved floral fragrance, as determined by volatile organic compounds, may be a route to improving pollinator attraction for oilseed and confectionary production and could also add value to ornamental sunflowers. Wild relatives of H. annuus have a long history of being used to breed improved traits into cultivated varieties, yet it is unknown whether favorable scents are present in wild Helianthus species and thus an available resource for fragrance breeding. In order to assess the diversity of floral fragrance available in crop wild relatives, 30 diverse accessions of wild Helianthus as well as seven varieties of H. annuus spanning a domestication gradient were grown in greenhouse experiments and variation in floral volatiles was analyzed by solid phase microextraction-gas chromatography-mass spectrometry. While alpha-pinene made up a significant portion of the volatiles emitted for most taxa, there was substantial diversity present across the genus as well as within H. annuus. Most volatiles emitted were monoterpenoids with a significant share of sesquiterpenoids. The diversity identified here will inform further targeted study of which compounds affect pollinator attraction and health. Several wild accessions such as Helianthus debilis subsp. tardiflorus and Helianthus praecox subsp. praecox as well as open-pollinated domesticated accessions of H. annuus show promise for breeding for improved floral fragrance due to high volatile abundance and likely favorable compound compositions. [ABSTRACT FROM AUTHOR]

Wild Helianthus species have been undeniably beneficial in sustaining the sunflower crop by providing plant breeders with a diverse genetic pool of potentially useful traits. Exploration to collect populations of wild sunflowers is one of the more difficult and challenging activities in the conservation and utilization of these valuable genetic resources. The logistics of collecting requires careful planning, locating the target species, obtaining permission to access and collect, and timing the exploration to ensure the availability of mature seed. The US Department of Agriculture, Agricultural Research Service (USDA-ARS) established the wild Helianthus seed collection in 1976 at Bushland, Texas with the goal of collecting and conserving the broadest representative genetic diversity possible and serving as a central repository of germplasm and related information. In 1985 this collection was transferred to UDSA-ARS, North Central Regional Plant Introduction Station, Ames, Iowa. Over the last half century, 37 explorations were undertaken covering 175,000 km to collect the 53 Helianthus species from their distributional ranges in the forty-eight conterminous states in the US, three Canadian Providences (Manitoba, Saskatchewan, and Alberta), Argentina and Australia. The many explorations have created a global crop wild relatives (CWR) genebank collection. The current wild CWR sunflower genebank contains 2562 accessions of 53 species with 1065 wild Helianthus annuus accessions (42 %), 617 accessions representing populations of the 13 other wild annual species (24 %), and 880 accessions representing 39 perennial species (34 %). This collection is the largest and most genetically diverse ex situ sunflower collection in the world and is vital to the conservation of wild sunflower species for the global sunflower community. [ABSTRACT FROM AUTHOR]

Downy mildew is one of the most important diseases of sunflower crop around the world caused by Plasmopara halstedii (Farl.) Berl.et de Toni. The aim of our study is the sunflower hybrid development with the durable resistance to downy mildew, combining one parental line with the most effective for the specific location major gene (Pl15 for example) and the second parental line – with a high horizontal resistance to downy mildew. Experiments were conducted at All-Russia Research Institute of Oil Crops in 2016–2021. Experimental design was randomized blocks with three replications. CMS-lines with the highest level of horizontal resistance (VK 678, VA 732, VK 680, VK 934, VK 900 and new line SL 0516) were used as mother parents. Lines with Pl15, resistant to all the downy mildew races were used as pollinators to create sunflower hybrids with durable resistance to downy mildew. A number of high-productive sunflower hybrids with durable resistance to DM (VK 732А × L 642-15, VK 732А × L 634-15, VK 680А × L 642-15, VK 680А × L 634-15, VK 934А × L 642-15 and VK 678А × L 634-15) were developed and tested. [ABSTRACT FROM AUTHOR]

The present investigation is directed at improving sunflower using hybrids having diverse cytoplasmic male sterile (CMS) sources from Helianthus annuus and H. argophyllus. The aim is to develop and identify promising lines and hybrids with a high combining ability and to obtain highly productive oilseed sunflower hybrids having diverse CMS sources. Five diversified CMS lines and 10 testers were crossed in a line × tester mating design to develop 50 F1 hybrids for genetic analysis. The pooled analysis of variance revealed significant differences among hybrids for the traits studied. The mean squares of lines and testers from crosses and GCA variance components revealed the prevalence of additive variances and additive gene action. The mean squares of lines × tester interactions were also significant for all the traits considered. The significance of lines × tester interactions and SCA variance components indicated that SCA is also important in the expression of traits and demonstrated the role of dominant and epistatic genes in controlling the various traits. Among the diverse CMS lines, ARG-6-3-1-4was identified as the best general combiner for stem diameter, volume weight, seed yield, hull content and oil content. While, the line ARG-2-1-2 was the best general combiner for days to 50 per cent flowering, head diameter, 100 seed weight and seed filling per cent. The tester M17-R was observed to be the best general combiner for earliness and volume weight, while RHA 93 was the best general combiner for plant height, seed yield and oil content. The crossMUT-2-8-3-2 × GKVK 3 was found to be a good specific combiner for stem diameter, 100 seed weight, seed yield, seed filling percentage and oil content while, ARG-6-3-1-4 × GKVK 3 was a good specific combiner for days to 50% flowering, plant height and 100 seed weight. The highest standard heterosis for seed yield was observed in the hybrid MUT-2-8-3-2 × GKVK 3 followed by ARG-2-1-2 × LTRR 822 while for oil content the highest was seen in the cross ARG-6-3-1-4 × RHA95-C-1 and thus these hybrids can be exploited for sunflower improvement and diversifying the cytoplasmic male sterile sources of this valuable oilseed crop. [ABSTRACT FROM AUTHOR]

Weed infestation induces intense competition with the sunflower crop for soil nutrients, space and light causing significant yield losses of the sunflower. Therefore, study was undertaken during the year 2013–15 at College of Agriculture, University of Sargodha, Pakistan to determine the effect of Cyperus rotundus infestation on various morphological and biochemical traits. Initially a screening experiment was carried out to screen against C. rotundus infestation. Later on, cross combinations of selected cytoplasmic male sterile and restorer lines were attempted to develop F1 progenies which were compared with commercial hybrids along with parents. There were 6 parental lines (3 A and 3 R lines) along with 9 single cross combinations obtained from these parents. Experiment was carried out in complete randomized design having factorial arrangement with three replications. Weed in one of regime latter called as control were completely absent, while in weed infestation regimes 5 and 10 plants of C. rotundus were maintained. Results showed that C. rotundus infestation causes significant damage to the sunflower plants. Generally cross combination showed a decrease of leaf area by 440% and 264%, 61% and 49% for chlorophyll contents, 133% and 191% for head weight under low and high weed infestation regime respectively. However, antioxidant activity increased by 44% and 49% under low and high infestation regime induced by C. rotundus. Sunflower genotypes also showed variability in competitive ability against C. rotundus weed. Cross combinations coded as (A10, A7 and A2) showed lower comparative decrease for seed yield and oil contents when compared with standard hybrids under the presence of C. rotundus. Development of sunflower hybrids with better competitive ability under the presence of weeds such as C. rotundus may able to enhance plant development and lower yield losses in sunflower field with minimum the use of herbicide. [ABSTRACT FROM AUTHOR]

The sunflower is a strategically important oil crop. Every year the area under this crop grows, and the rapid returning of sunflowers back to the fields provokes the formation of new more aggressive races of broomrape (Orobanche cumana Wallr.). Broomrape is a parasite that interferes with the normal development of sunflower and can lead to significant crop losses. For creating a sunflower hybrid (F1) it is needed to cross the parental components, which have a complex of important traits, among which there is a resistance to the herbicides and a broomrape. Considering that the creation of each of the components of the hybrid involves many years of painstaking work in the breeding process, modern approaches and methods are used to accelerate the creation of a new source material. Thus, using the technology of cultivating immature embryos in vitro culture, it is possible to reduce the time to create lines resistant to herbicides, for example. And during selection for resistance to pathogenic organisms, testing is most often used against an artificial infectious background, both in the field and in laboratory conditions, in order to differentiate the material on this basis. The aim of this work was to establish the effectiveness system when creating an initial breeding material resistant to herbicides and broomrape. As a result of testing the lines on an artificial infectious background, was identified plants which have high resistance to the G-race broomrape and were isolated from hybrid combinations resistant to tribenuron-methyl and imidazolinones. Thus, among the analyzed plants which are resistant to tribenuron‐methyl, four lines were isolated, which are highly resistant to the G-race broomrape from a hybrid combinations BH0118/SURES–2 (101/1, 101/4, 101/6, 101/7), and BH0318/SURES–2 (101/21, 101/24, 101/28, 101/30), and five lines (101/11, 101/12, 101/16, 101/17, 101/18) from a hybrid combination BH0218/SURES–2. Among imidazolinone-resistant sunflower lines – line 3 was isolated as highly resistant to the G-race broomrape. [ABSTRACT FROM AUTHOR]

Phyllody in sunflowers (Helianthus annuus L.) is characterized by the appearance of bracts and ray flowers in the centre of the heads. It has been discussed for decades among the sunflower plant breeders and experts without a clear "unique" explanation for it. The erratic appearance of the phenomena has led to consider it either a disease or hybrid defect and the plants with Phyllody as off-types, raising several farmers claims to seed producers. However, the auxins gradient, in the growing Asteraceae heads, determines the differentiation pathway of the undifferentiated cells. i.e., bracts and ray flowers at the border and disk flowers in the centre of the head. Disruption of the natural auxin gradient alters the cell differentiation in the growing heads and causes bracts and ray flowers to grow where only disk flowers should grow. The disruption of the natural head bottom auxin gradients may be caused by small injures in the fast-growing head receptacle. The most common causes of Phyllody are hormonal herbicide damage and Boron (B) deficiency, even temporary. Plants growing with B deficiency have brittle cell wall and membranes while a plant with high B levels produces plastic or elastic cell wall and membranes. Brittle cell walls are susceptible to breaks during growth. Sunflowers genotypes may react to crack or small damages in the sunflower bud in two ways. Some tend to repair the damages by regrowing new organs such as ligules or bracts and forming Phyllody. Others do not regrow and only heal the wound creating the funnel hole head shape. [ABSTRACT FROM AUTHOR]

Sunflower is cultivated around the globe to meet various nutritional, medicinal and industrial needs. The seed is a rich source of edible oil, protein, vitamins, antioxidants and other micronutrients. It is considered a source of healthy diets and has been recommended to improve the human immune system as well as to cure various chronic diseases. Sunflower seed oil contained polyunsaturated fatty acids (linoleic acid), tocopherols and phytosterols, which tends to lower low-density lipid and improve immunity against various human diseases. Its seed and plants parts have been directly exploited as a source of herbal medicine. Methanolic extract of seed and other parts contained diterpene, carboxylic acid, aldehyde, steroid, polyphenol, vanillic acid, ferulic acid, trans-caffeic acid, coumaric acid, nicotinic acid, allelochemical and other aromatic compounds, which may help to cure several chronic human diseases without side effects as mentioned in this review. Future research should be carried out to fully exploit the usefulness of this plant against epidemic outbreaks. [ABSTRACT FROM AUTHOR]

New traits that are useful for the cultivated sunflower can be received by applying classical breeding methods. A new form sunflower that is resistant to herbicides Pulsar and Express was obtained by hybridization between the sunflower mutant M-95-674 and the line HA 425. Test results from the period 2017–2019 confirm the resistance to both herbicides. This resistance can be transferred into other classical selected lines. [ABSTRACT FROM AUTHOR]

Carduus acanthoides L (spiny plumeless thistle) a biannual wild species with 2n = 22 chromosomes was crossed with Helianthus annuus L. When crossing, pollen from C. acanthoides germinated and pollinated the stigmas of sunflower lines HA 89A after 48 h. The crossability rate was low, but seeds and hybrid plants were obtained. The F1 plants strongly resembled the cultivated sunflower with the most important bio-morphological characters, even though they had an intermediate type of heritability. The hybrid nature was confirmed by RAPD markers. The polymorphism between H. annuus, C. acanthoides, and their F1 hybrids was studied using RAPD. The result showed introgression of C. acanthoides in the hybrid progeny. It was established that the wild species carried Rf genes for the CMS PET-1. After self-pollination and sib-pollination of the F1 plants and back-crossing with cultivated sunflower, F2, BC1 and next generation hybrid progenies were obtained. The investigation encompassed the period 2000–2007 and 2014–2018. Some of the new lines have been included in a heterosis breeding program for developing hybrids for the sunflower market. [ABSTRACT FROM AUTHOR]

Helianthus annuus subsp. annuus and H. petiolaris are wild North American species that have been naturalized in central Argentina. They have a sporophytic self-incompatibility genetic system that prevent self-fertilization but the occurrence of self-compatible plants in Argentina was observed in both species and could in part explain their highly invasive ability. Their geographical distribution coincides with the major crop area. The domestic sunflower is self-compatible, can hybridize with both species and presents a considerable amount of gene flow. The aim of this study is to understand the self-incompatibility mechanism in both wild Helianthus species. Reciprocal crossing and seed production were used to identify self-compatible genotypes, the number and distribution of self-incompatibility alleles within populations and the type and extent of allelic interactions in the pollen and pistil. The behaviour of S alleles within each population was explained by five functional S alleles and one non-functional allele in each species, differing in their presence and frequency within accessions. In both species, the allelic interactions were of dominance/recessiveness and codominance in pollen, whereas it was only codominance in the pistil. Inbreeding effects in wild materials appeared in the third generation of self-pollination, with lethal effects in most plants. The number of S alleles is low and they behave in a similar way of other Asteraceae species. The self-compatibility was addressed to non-functional S alleles introgressed in wild Helianthus plants through gene flow from self-compatible sunflower. [ABSTRACT FROM AUTHOR]

To evaluate the effect of different micronutrients (Mn, Fe, Zn) and farmyard manure (FYM) on the vegetative, phenological, and achene yield components of sunflower a field experiment was conducted in Maragheh, North West of Iran during the growing season 2018–2019. The treatments were arranged in a split-plot design- with three replicates. The main plots assigned to two levels of FYM (0 and 20 t ha−1) and sub plots assigned to the recommended dose of three micronutrients (Mn, Fe, Zn). The results revealed significant improvements in the growth and yield of sunflower due to the main and interaction effects of farmyard manure and inorganic fertilizer application. The highest number of leaves and the highest leaf area was observed in a plant grown by FYM + Zn. However, there was no significant difference between micronutrients under inorganic condition (without FYM application). The highest leaf relative water content (RWC), plant height, internode distance, and chlorophyll was recorded for plants grown by Fe or Zn under FYM applied condition. Application of FYM and micronutrients reduced the number of days to flowering. However, the application of FYM significantly delayed plant maturity. Achene number per head, 100-achene weight, achene length, achene width, achene oil percent, achene yield, and harvest index significantly increased with the application of FYM and the best performance was in a plant grown by FYM + Zn and FYM + Fe. The percentage of hollow and empty achene was significantly reduced by the application of FYM. Combined applications of FYM and micronutrients has become an increasingly common practice. [ABSTRACT FROM AUTHOR]

Inbred line Mh174B with the yellow coloration of the sunflower plant top was produced by hybridization of annual wild species with cultivated sunflower. The aim research was to evaluate genetic control of yellow coloration of the sunflower plant top in combination with other morphological traits (branchiness, pollen fertility restoration and ray flower coloration). A total of four F2 hybrid combinations of were created: Сх1010А × Mh174B, Сх1012А × Mh174B, Сх2111А × Mh174B, Мх845А × Mh174B. Yellow coloration of the sunflower plant top was shown to follow a monogenic mode of inheritance and, presumably, be controlled by the gene y. This trait is inherited independently from such traits as branchiness, pollen fertility restoration and ray flower coloration. The mainstreams of use of yellow coloration of the sunflower plant top in sunflower breeding and seed production are discussed. [ABSTRACT FROM AUTHOR]

One of the most threatening holoparasitic plant species is Orobanche cumana Wallr. (sunflower broomrape), mainly distributed in the Mediterranean region and Western Asia where it exclusively parasitizes sunflowers. Sunflower broomrape (BR) is a very destructive parasitic weed causing significant yield losses under high infestations that can easily spread and is vulnerable to mutations. Broomrape is highly variable, controlled by vertical single dominant resistance genes leading to the rapid and frequent breakdown of resistance. This subsequently leads to the continuing need for new unique genes from multiple sources for controlling new emerging virulent races. The USDA-ARS, National Plant Germplasm System crop wild relatives (CWR) collection contains 2,519 accessions of 53 species with 14 annual species (1641 accessions) and 39 perennial species (878 accessions). This CWR collection provides a vast genetic resource for new BR resistance genes, especially in Europe and the Middle East. Sunflower CWR evaluations for new resistance genes for BR races have demonstrated that they are a substantial reservoir for existing and new emerging virulent races. Resistance to sunflower broomrape, including immunity, has been reported in seven annual and 32 perennial species. These sources discovered in the sunflower CWR confer resistance to new virulent broomrape races F, G, and H, and others that have not been assigned a race designation. Since several of the resistant CWR sources are annual and have the same chromosome number as cultivated sunflower, broomrape resistance genes can be incorporated into hybrid sunflower through interspecific hybridization. The diverse sources of resistance from the CWR provide breeders with the prospect for durable broomrape control through exploiting genetic resistance for existing and newly emerging races. [ABSTRACT FROM AUTHOR]

Aim of our research was to study the genetic diversity and establish the inheritance of top branching trait in the collection of 34 sunflower lines of the Institute of Oilseed Crops of the NAAS. Experiments were carried out in 2005–2016 according to classical cultivation methods, using manual castration, crossings, forced self-pollinating, isolation and visual assessment of the first and second generation of obtained descendants. The statistical reliability of the obtained ratio was confirmed by calculating the Pearson's chi-squared test. Presence of two loci determining the inheritance of the branching trait in sunflower was established. In one locus, recessive alleles are responsible for manifestation of the branching trait. In the second locus, dominant alleles are responsible for the manifestation of the branching trait. In 23 lines of sunflower, it was established that a recessive homozygote for one gene causes phenotypical top and full branching. In 8 lines of the collection, full branching trait is due to the dominant allele of the gene. In the lines InK235, APS49, the presence of two genes was established, the dominant alleles of which determine full branching trait. In the APS56 line, full branching is controlled by the dominant alleles of three genes. [ABSTRACT FROM AUTHOR]

Highlights from the article: HELIA EDITOR IN CHIEF Dragan Skori'c, Serbia MANAGING EDITOR Zvonimir Sakac, Serbia EDITORIAL BOARD Walter Anyanga, Uganda Yakov Demurin, Russia Maria Duca, Moldova Valentina Entcheva, Bulgaria Jose Fernández-Martinez, Spain Wolfgang Friedt, Germany Oleg Gorbachenko, Russia Antonio Hall, Argentina Renate Horn, Germany Brent Hulke, USA Yalcin Kaya, Turkey Nataliya Kutishscheva, Ukraine Nicolas Langlade, France Maria Pacureanu-Joita, Romania Begoña Pérez-Vich, Spain Monica Poverene, Argentina Lili Qi, USA Mulpuri Sujatha, India Gian Paolo Vannozzi, Italy Kirichenko Victor Vasyljovich, Ukraine Felicity Vear, France Abelardo de la Vega, Argentina-Spain Jovan Crnobarac, Serbia Ferenc Viranyi, Hungary Jun Zhao, China HELIA is published by the Serbian Academy of Sciences and Arts (SASA), Branch in Novi Sad in cooperation with De Gruyter. HELIA publishes original theoretical, experimental and technical contributions arising from the scientific study of sunflower crops and farming systems. The subject fields covered include crop agronomy; sunflower genetic resources; sunflower improvement and breeding; phytopathology and plant protection; sunflower physiology, biochemistry, metabolism, structure, genetics, at diverse levels of integration; ecology; soil, water and mineral nutrition management and farming systems.

Two field trials were conducted on the Research Farm of the Institute of Food Security, Environmental Resources and Agricultural Research, Nigeria during the late cropping seasons (Jun.–Nov.) of 2014 and 2015 to evaluate the agronomic performance of four recently released sunflower varieties (SAMSUN-1, SMASUN-2, SAMSUN-3 and SAMSUN-4) to three fertilizer regimes: Control, Split application of 30 kg N + 28 kg P2O5 at 21 days after sowing (DAS) and at anthesis and Single application of 60 kg N and 56 kg P2O5 at 21DAS. The experiment was laid out in a randomized complete block design using a 3 × 4 factorial arrangement and replicated three times. Data were collected on phenology, plant height, seed yield and yield attributes, and quality. The varietal effect was only significant in 2015 for head weight, a number of achene per head and 100 achene weight. Application of N and P fertilizer either as split or single significantly (P ≤ 0.05; F-test) enhanced plant height at R5 and R9, 100 achene weight, achene weight per head and grain yield in both years. Single application resulted in significantly (P ≤ 0.05) higher grain yield in 2014 than the split and control and was on par with a split. Significant variety × fertilizer regime was recorded for protein content in 2014 and 2015, and oil content in 2015. Therefore, a single application of N and P fertilizers at 21 WAS is recommended for adoption in the humid tropics to enhance seed and oil production of SAMSUN-3 and SAMSUN-4. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the best performing lines in sunflower on the basis of phenotypic and genotypic correlation so that we can find out the which trait directly or indirectly effect the yield and quality of the sunflower because being an breeder our main aim is yield and quality and the lines which are performing best can be further used in the breeding programs. Sunflower is a valuable oil producing crop because it contains good quality oil composition and can be grown twice in a year. There is scarcity of oil in our country so that there is requisite to heighten the yield of sunflower in order to exploit its share in oilseed sector. The study was conducted at the research field of Rajawala farm, University of Agriculture, Faisalabad during year 2015–16 to study the correlation among yield related traits, oil and protein content in Sunflower (Helianthus annuus L.). 20 sunflower lines were sown in randomized complete block design with three replications. Data was assessed at maturity for plant height, leaves per plant, leaf area, head diameter, internode length, 100-achene weight, achene yield per plant, oil contents and protein contents. Genotypic and phenotypic correlation was estimated among these traits. The recorded data was subjected to statistical analysis of variance, correlation and path coefficient analysis. The line G-16 showed best performance for leaf area, head diameter and achene yield per plant. Line G-20 was good in 100 achene weight. The above mentioned lines could be used in future breeding programs for effective improvement in yield of sunflower. This data was helpful to select superior lines and these lines may also be used in further hybridization program to get better yield, oil and protein contents. [ABSTRACT FROM AUTHOR]

The present research aimed to study gene effects for oil content and fatty acid composition in sunflower. It involved a set of 92 hybrids developed by crossing four CMS lines with 23 perfect restorers. Experiment was conducted at experimental field area of Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, Punjab, India. The data was recorded on oil content and quality traits. The analysis of variance revealed significant differences among the traits studied. Among the lines; CMS 42A was observed to have higher significant positive gca effects for oil content, linoleic acid & linolenic acid and higher significant negative gca effects for palmitic acid and stearic acid, whereas, for oleic acid line, CMS 40A had higher positive gca effects. Among the testers, TSG 275 had higher significant positive gca effects for linolenic acid and significant negative gca effects for stearic acid. High positive gca effects for oleic acid and oil content were observed for TSG 331. The tester OPH 91 was good combiner with high positive gca effects for oleic acid and negative gca effects for palmitic acid, whereas, tester TSG 288 exhibited highest positive gca effects for linoleic acid. The best cross combinations; CMS 40A×TSG 259, CMS 607A×TSG 271 and CMS 40A×OPH 73 showed significant specific combining ability effects for oil content and cross CMS 40A×TSG 289 had significant specific combining ability for oleic acid and linoleic acid. The cross combination CMS 40A×TSG 259 is giving a significant jump of over 12 % against the current commercial check for oil percentage and for other quality traits more than 50 % over the standard check, which is significant for undertaking improvement of hybrid for oil quality. [ABSTRACT FROM AUTHOR]

In breeding programs, it is imperative to recognize the genetic variations and levels of association between traits that directly or indirectly affect the yield. Achene yield and related traits in forty-nine sunflower genotypes were studied for genetic variability, correlations and path coefficient analysis. The phenotypic coefficient of variation (PCV) were higher than the genotypic coefficient of variation (GCV) for the all the studied traits in sunflower. The most active association of achene yield was found with achene/head, 100-achene weight and plant height. However, oil contents had a negative association with achene filling percentage, 100-achene weight, number of leaves and stem diameter. The maximum direct influence on achene yield were exerted by head diameter followed by achene filling percentage, 100 achene weight, achene/head and number of leaves. In contrast, plant height, days to maturity and stem diameter had the negative direct impact on yield. The genetic correlations were higher than phenotypic correlations which suggest that environmental influences were very low. Our results showed that achene/head, 100 achene weight, plant height and head diameter are important plant traits which should be considered while planning any breeding program for higher achene yield in sunflower. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis in vitro provides an efficient means of plant multiplication, facilitating sunflower improvement and germplasm innovation. In the present study, using interspecific amphiploids (2n = 4x = 68) between cultivated sunflower and wild perennial Helianthus species as explant donors, somatic embryos were induced directly from the surface of corolla tubes at the late uninucleate or binucleate microspore development stage. Primary somatic embryos (PSEs) were obtained in amphiploids G08/2280 (H. pumilus × P21) and G08/2260 (NMSHA89 × H. maximiliani). The PSE induction frequency of G08/2280 on synthesized Medium A and B was 30.27% and 42.42 %, respectively, while that of G08/ 2260 was 5.89% and 12.16%, respectively. The difference of PSE induction frequency was significant between G08/2280 and G08/2260 (P = 0.0058), but was nonsignificant between induction Medium A and B (P = 0.1997). Secondary somatic embryos (SSEs) were rapidly produced from PSEs on subculture Medium 1 with the induction frequency of 100 %. The mean number of SSEs produced from each PSE was 19.2 and 12.2 in G08/2280 and G08/2260 within 30 d of subculture, respectively. Mature SSEs were gradually converted into young shoots on hormone-free subculture Medium 2, with the mean number of small green shoots produced from each PSE of 22.0 and 18.7 in G08/2280 and G08/2260, respectively. Through the additional process of rooting for some shoots without roots on half-strength of MS medium adding 0.25-0.5mg/l NAA, 0.5mg-1.0/l IBA, SE-derived shoots without roots gained about 40%rooting frequency. Regenerated plants acclimated successfully and displayed similar morphological and chromosome number to the amphiploid donors. [ABSTRACT FROM AUTHOR]

Secondary metabolites serve multiple functions in plants, and play a key role in many ecological processes. Accordingly, the quantification of such compounds is central to addressing many questions in plant science. Alongside precision analytical methods like gas and liquid chromatography-mass spectrometry, there exists a substantial niche for inexpensive and rapid spectrophotometric approaches if their usefulness in a system can be demonstrated. This study seeks to examine the utility of two commonly used colorimetric methods - the Folin-Ciocalteu assay and the aluminum complexation assay - for quantifying variation in leaf phenolic and flavonoid content among members of the genus Helianthus, the sunflowers. Among species known a priori to vary substantially in both the diversity and relative concentrations of secondary metabolites, both assays detect substantial variation among species. Moreover, total phenolic content as assessed by the Folin-Ciocalteu assay correlates positively with concentrations of multiple individual phenolic compounds as quantified by high performance liquid chromatography-mass spectrometry, indicating that the Folin-Ciocalteu describes variation in sunflower phenolic content. Additionally, the diversity of flavonoids known from Helianthus include a number of those known to be sensitive to the aluminum complexation assay, indicating that this assay may also be a useful descriptor of relative variation in sunflower flavonoid content. In total, both the Folin-Ciocalteu and aluminum complexation assays appear to capture useful, if coarse, variation in secondary metabolites among Helianthus species, and seem useful as rapid low-cost methods for exploratory research, preliminary analyses, and potentially useful for high-throughput phenotyping within wild or cultivated sunflower with proper calibration. [ABSTRACT FROM AUTHOR]

Orobanche cumana is found in the Iberian Peninsula as an allochthonous species parasitizing exclusively sunflower, in contrast to the closely related species Orobanche cernua, which is an autochthonous species that only parasitizes wild Asteraceae hosts. Ten O. cumana populations were collected in the two traditional areas of sunflower broomrape occurrence, the Guadalquivir Valley, Southern Spain (six populations) and Cuenca province, Central Spain (four populations). Twelve O. cernua populations were collected on wild hosts across its natural distribution area in Southeastern Spain. Genetic relationships within and between both sets of populations were studied using a set of 50 robust and co-dominant SSR markers from O. cumana. The results supported the taxonomic separation of the two species and the existence of two distant genetic groups for O. cumana, one in Guadalquivir Valley and another one in Cuenca province. The inter- and intra-population variability was extremely low for O. cumana, whereas the overall genetic diversity was much higher for O. cernua. The genetic structure of O. cumana populations probably reflects a founder effect, with the two genetically distant groups deriving from separate introduction events. The high degree of genetic differentiation observed in O. cernua is mainly explained on the basis of restricted gene flow due to ecological barriers together with the occurrence of a predominantly self-pollinating mating system. Complementary diversity studies on both species in its current distribution area are required for understanding global genetic variability and evolutionary characteristics of the parasitism. [ABSTRACT FROM AUTHOR]

This study was conducted during 2009 and 2010 at Regional Agricultural Research Station, Nandyal, Andhra Pradesh, India to evaluate the feasibility of subsurface drip irrigation (SDI) in vertisols and its influence on sunflower crop under two lateral spacings with two lengths of lateral and two levels of nitrogen. The experimental design was a split split plot with three replications. Laterals, buried at 30 cm depth in the soil, were set as per treatments, and emitters are spaced 40 cm apart. The experimental results indicated that the SDI with lateral spacing of 150 cm is feasible in vertisols with 75 kg N/ha can be adopted, and length of lateral can be adjusted depending on the layout of the SDI system in the field. [ABSTRACT FROM AUTHOR]

Wild sunflowers are a source of desirable traits for improving cultivated sunflower Helianthus annuus (ANN). Two wild species of sunflower, H. argophyllus (ARG) native to coastal sand dunes and H. niveus ssp. tephrodes (TEPH) native to the desert sand dunes, have been hypothesized to be drought resistant. We tested the expectation that these wild species would have higher percent germination and more uniform germination under simulated drought stress conditions compared to cultivated ANN. In a growth chamber study, we assessed germination of ANN, ARG and TEPH (three representative accessions for each species) under four osmotic stress treatments imposed using polyethylene glycol to simulate varying levels of drought stress: 0, -0.4, -0.8 and -1.2 MPa. As expected, all three species responded to increasing simulated drought stress with decreased percent germination assessed after seven days and delayed germination timing and uniformity assessed with logistic regressions. ARG responded marginally better than ANN with a greater percent germination at -1.2 MPa and greater uniformity at 0 and -0.4 MPa. Although the ARG advantage was small, this suggests that ARG × ANN recombinant hybrids may deserve further investigation to see if desirable alleles can be identified for improving cultivated ANN germination and establishment under mild drought conditions. In contrast, TEPH responded with substantially lower percent germination and less uniformity than ANN, suggesting that it is unlikely that TEPH will be useful as a donor of desirable drought resistance alleles. [ABSTRACT FROM AUTHOR]

IMISUN, SURES, and CLPlus are three herbicide tolerance traits in sunflower ( Helianthus annuus L.) which are determined by the expression of different alleles at the same locus, Ahasl1. Introgression of these genes into high yielding sunflower germplasm should be complemented through the use of molecular markers in order to unambiguously identify the different alleles involved in tolerance. The aim of this work was to present a set of allele specific molecular markers for the different herbicide resistant traits of sunflower, which can be used with various technological platforms, and applied to different objectives in a breeding program. The Ahasl1 gene sequences from lines carrying different alleles for susceptibility or resistance showed single nucleotide polymorphisms and length variations for a simple sequence repeat. These differences were utilized to develop three types of PCR markers (SSRs, CAPS and SNPs) which allow the precise identification of each allele at the Ahasl1 locus. Usefulness of these markers with respect to the application of phenotypic selection for herbicide tolerance, and the strategic implementation of these techniques for developing inbred lines with herbicide resistance is discussed. [ABSTRACT FROM AUTHOR]

Vegetable oils and fats are vital components of the human diet because they are an important source of energy. In 2008, according to the production data, sunflower was grown in Turkey on an area of 577,958 ha and 992,000 metric tons of the seed were harvested (Anonymous, 2010). Because of the gap in vegetable oil production in Turkey, sunflower is one of the alternatives and the leading oilseed crop that can be used to increase the vegetable oil production in the country. Growing sunflower as a crop in the Aegean Region is one of the possibilities to increase the production. The main objectives of this study were to identify oilseed hybrids and open-pollinated confectionary varieties that could be grown with satisfactory yield performance in the Aegean Region. The experiments including oilseed and confectionary types of cultivars were conducted separately during the first crop-growing seasons of 2008 and 2009 on the experiment field of the Aegean Agricultural Research Institute in Menemen, Izmir. The experiments were conducted in a randomized complete block design with four replications. Oilseed hybrids and open-pollinated confectionary sunflower candidate varieties were used in the study as the material. An adaptation study was undertaken for the characters of seed yield, seed oil content (%), 1000-seed weight, plant height, head diameter, seed length, seed width, hull percentage (%), seed color (white, black, and intermediate), days to flowering, and days to physiological maturity. The results indicated that statistically significant differences were found among the sunflower varieties for the characters in question. In the oilseed variety experiments, the highest seed yield (572 kg da-1) and the lowest seed yield (343 kg da-1) were obtained in 2009 from the varieties ETAE-Y-TM-2007-5 and Armada, respectively. In the confectionary variety experiments, the highest seed yield (563 kg da-1) and the lowest seed yield (202 kg da-1) were produced in 2009 by the varieties ETAE-D1-2-B2 and ETAE-Ç-P-1-2, respectively. [ABSTRACT FROM AUTHOR]

Wild Helianthus annuus naturalized in Argentina could be a valuable germplasm source for cultivated sunflower. Five wild populations collected in different environments and with different phenotype expression were evaluated as a genetic resource in a common garden study. The populations showed normal meiosis and produced a good seed set when their plants pollinated the male-sterile inbred line A09 ( cms PET1). The wild populations restored more than 80% fertility of the HA89 ( cms PET1) and A10 ( cms PET1) inbred lines in the F1 generation. The fertility of one male sterile source from Mendoza was restored (>95%) by the maintainer line B10. The fatty acid composition differentiated a population from Entre Ríos with a high saturated fatty acid content (>107 g kg-1). Another population from La Pampa showed a high level (>50%) of resistance to the Sunflower Chlorotic Mottle Virus (SuCMoV). No wild populations showed tolerance to imazaphyr sprayed at 2× doses (×=80 g i.a. ha-1). A population collected in the coolest environment showed high tolerance to low temperature (15/5°C, neutral day) in the initial grow stages (<3 expanded leaves). A population collected in a dry and hot habitat showed the highest germination (>80%) under water stress (-0.4 MPa) imposed by polyethylene glycol 6000. This population and a second one from southern Buenos Aires showed the lowest leaf temperature increase (<10%) and the highest foliar specific density under artificial drought during the R4 to R6 reproductive stages. It was concluded that wild H. annuus naturalized in central Argentina can supply some useful traits for sunflower breeding. [ABSTRACT FROM AUTHOR]

A five year field trial evaluated 71 oilseed sunflower, Helianthus annuus L., accessions, 32 breeding lines, and 25 interspecific crosses for resistance to infestation by naturally occurring populations of the banded sunflower moth, Cochylis hospes Walsingham (Lepidoptera: Tortricidae), in North Dakota. Germplasm with resistance to attack by the banded sunflower moth and subsequent larval feeding damage in the seeds was identified. PI 251902 had less than 10% feeding damage per head in all five years of testing and less than 6% in three of the five years. PI 372259 and PI 170401 exhibited 12% or less seed damage in three years of evaluation and PI 253776 had only 3% damage in two of the three years and was the least damaged in 2004. Four other accessions (PI 170385, PI 291403, PI 494859, and PI 505651) revealed resistance in three of five years. A number of the interspecific crosses which were retested based on earlier results showed reduced seed damage in 2003, but subsequently exhibited much greater damage the following year due to higher populations of banded sunflower moth. Hybrid 894 was earlier used by others as a susceptible check; however, in the current investigation, this hybrid consistently had the lowest average seed damage from C. hospes feeding among the germplasm evaluated. Results from this investigation indicate that there is potential for developing resistant genotypes with reduced feeding injury that will help sunflower producers reduce yield loss due to the banded sunflower moth. In addition, plant resistance can effectively be combined with delayed planting to decrease densities of C. hospes, thus reducing crop losses without disrupting the control of the larvae by parasitoids. [ABSTRACT FROM AUTHOR]

Biofuels from wood, wastes and various agricultural crops are currently quite expensive. Seed oil plants, instead, represent a relevant renewable natural resource for biodiesel to be used as engine fuel. In consequence, new genetic modified varieties (GMV) have been obtained by biotechnological methods, which offer a wide range of special oils for bio-energetic purposes. However, growing sunflower GMVs for biodiesel production could create a potential risk due to pollen flow from transgenic to non-transgenic varieties when grown in the same geographic areas. Presently, pollen flow analysis by DNA-based tools is expensive and time consuming, and new, cheap and rapid methods are needed. The goal of this research was to estimate pollen flow in sunflower by using a "composite" line, with a monogenic dominant marker (TT) for a high phenotypic expression of blue leaf nervure, as pollinator, and an inbred line and a cytoplasmic male sterile line (cms) as recipient plants. The obtained results suggest that cytoplasmic male sterility could be used for the analysis of sunflower pollen flow. [ABSTRACT FROM AUTHOR]

An experiment was conducted during summer and kharif seasons of 2004 and 2005 at Agricultural Research Station, Bhavanisagar, to study different irrigation methods and regimes (IW/CPE ratio) on yield attributes, yield and water economy in hybrid sunflower (MSFH 17). Yield and yield attributes varied significantly during both summer and kharif seasons of 2004 and 2005. Irrigation at 0.80 and 0.60 IW/CPE ratios under alternate furrows and paired row system of irrigation (80/40 x 30 cm) proved better than other treatment combinations with regard to water use efficiency gross return, net return and B0 : C ratio. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) is an important oilseed crop. Several pest are known to attack sunflower crop. Sunflower cultivation in Marathwada region (M.S., India) has recently been threatened by a new pest, the stem borer Nupserha sp. near vexator (Pascoe). The stem borer appeared on sunflowers at Latur (M.S.) for the first time in India in 1993. Severe incidence of the stem borer was recorded in Marathwada region since 1998 which led to poor grain filling and ultimately yield loss to the extent of 30%. This situation led prompted us to test several conventional insecticides with the objective of finding a chemical that effectively controls the stem borer. A field study was carried out at Oilseeds Research Station, Latur (M.S.), during Kharif 2004-06. Six conventional insecticides were tested along with the untreated control. Application of quinalphos was found to be most effective and economic in controlling the stem borer, followed by chlorpyriphos and endosulfan. [ABSTRACT FROM AUTHOR]

Wild Helianthus annuus populations naturalized in central Argentina have spread since their introduction from the center of origin in North America. Phenotypic characterization based on 45 morphological and phenological descriptors of nine populations from different geographic regions of Argentina and 17 populations from the USA provided by the US Department of Agriculture germplasm bank at Ames, Iowa, was obtained by growing populations in an experiment field. Wild populations from Argentina reflected part of the phenotypic variability of populations from the center of origin, but showed adaptation to local conditions which allows differentiation between populations from each continent. All traits showed a continuous range, with majority of extreme values occurring in populations from North America. The populations that showed similarities for one group of descriptors differed in other traits, revealing the existence of different phenotypes. Helianthus annuus populations established in Argentina could be considered a differentiated genetic resource, containing new combinations and traits absent in North American populations, such as the life cycle length in the Diamante population of 180 days and longer, the longest of any population studied. [ABSTRACT FROM AUTHOR]

Seed morphology and disk diameter are agronomically most important traits for the confection sunflower. This paper reports the results of an analysis of quantitative trait loci (QTLs) underlying 10 seed morphological traits including seed and kernel size, shape and stripe, and disk diameter in both F2 population and F2:3 families derived from an oilseed by confection cross. A linkage map containing 165 target region amplification polymorphism (TRAP) and 44 simple sequence repeat (SSR) markers was constructed from 120 F2 plants. This map contained 17 linkage groups and spanned a total genetic distance of 1784.3 cM. A total of 51 QTLs were detected and 32 of them were identified in both generations. Each QTL explained 5.1-29.3% of the phenotypic variation, suggesting these traits were controlled by multiple genes. Most of the QTLs were clustered in six chromosomal regions. Two of the three QTLs identified for disk diameter were also located in two of the six regions. Moreover, alleles from the confection line at these QTLs had positive effects on these traits. Both QTL congruence and correlation analysis revealed that different genetic bases are responsible for seed shape, stripe, and other confection traits. The information generated by this study will facilitate confection sunflower breeding. [ABSTRACT FROM AUTHOR]

Studies were conducted on sandy clay loam soil (Typic Haplustalf) to evaluate the effect of five different tillage practices versus four irrigation regimes, 60 mm irrigation at IW/CPE=0.6, 0.8, 1.0 and 1.2, and their interaction on soil physical changes and performance of sunflower (Helianthus annuus L.) under rice fallow condition. Tillage in general had more positive effect on seedling emergence, growth and yield of sunflower than zero tillage in puddle rice fallows. Deep primary tillage with tractor-drawn disc plow or MB plow produced significantly larger heads with higher test weight, however, secondary tillage with rotavator, either power-tiller- or tractor-drawn, made finer tilth and recorded significantly higher seedling emergence (80.7%). Tillage with tractor-drawn disc plow + rotavator (deep-fine tillage) gave significantly higher mean seed yield (1311 kg ha-1) over tractor-drawn MB plow + tractor-drawn cultivator - deep tillage (1172 kg ha-1), ox-drawn desi plow + power-tiller-operated rotavator - shallow fine tillage (1054 kg ha-1) and ox-drawn desi plow + ox-drawn cultivator - shallow tillage (931 kg ha-1). The irrigation regime at IW/ CPE=1.2 recorded higher seed yield than IW/CPE=0.6, 0.8 and 1.0. Water use (ETa) by sunflower increased with increase in intensity of tillage and irrigation. WUE was higher in deep tillage practices and in irrigation regime of IW/ CPE=0.8. Deep tillage, besides saving 18% of irrigation water, resulted in about 24% higher sunflower seed yield compared with shallow tillage. Interaction effects revealed that significantly higher sunflower growth and yields (both seed and oil) was realized when tillage was done with tractor-drawn disc plow + rotovator coupled with scheduling irrigations at IW/CPE=1.0 or 1.2. Tillage with two passages of country plow + once with power-tiller-operated rotavator and scheduling irrigation at IW/CPE=1.2 produced significantly superior yields of sunflower than farmers' practice. [ABSTRACT FROM AUTHOR]

Efficacy of a synthetic detergent "Surf Excel" as a potential male gametocide in Helianthus annuus was evaluated. Foliar applications of three concentrations of "Surf Excel" solution (1.0, 2.0 and 3.0% w/v) at different plant development stages caused reduction in plant height, pollen fertility, total yield/ plant, 100-seed weight and brought about early flowering in comparison with control plants. All treatments with "Surf Excel" solution caused elongation of the style in floral buds resulting in protrusion of receptive stigmas from the buds, which facilitated cross-pollination by honeybees. The plants sprayed once with 1% "Surf Excel" solution exhibited protruded receptive stigmas and 99.87% pollen sterility along with insignificant reduction in total yield in comparison with control plants. [ABSTRACT FROM AUTHOR]

Three varieties, CO 4, Morden and TNHSF 239 (a pre-release culture) and two hybrids, TCSH 1 and KBSH 44, were selected for this study. Simple correlation coefficients were estimated among characters for individual varieties and hybrids. Two traits, seed yield and 100-seed weight, are important selection indices for oil yield improvement in both varieties and hybrids. Head weight can be considered as a selection index for improvement of seed and oil yield in hybrids only. Likewise, oil content is an important selection index for oil yield improvement in varieties. It can also be inferred that the results obtained from the association analysis of pooled data for varieties and hybrids will give ambiguous results and have a negative impact on the yield improvement program. Thus it is desirable to compute separate association analyses for each variety and hybrid to identify effective selection indices for the improvement of sunflower. [ABSTRACT FROM AUTHOR]

A dwarf mutant has been derived from M2 gamma irradiated Morden population of sunflower (Helianthus annuus L.). The dwarf mutant has the height of 35 cm and the earliness of 65 days. This mutant has been selfed and forwarded to the M3 and M4 generations and it did not deviate significantly from the expected segregation ratio since it has the recessive monogenic character. Althogh the earliness and height showed a drastic reduction, the seed yield and oil content were on par with the parent Morden. [ABSTRACT FROM AUTHOR]

The experiment was carried out to induce variability in the sunflower varieties Morden and CO 4 (TNAUSUF 7) by a physical mutagen, i.e., gamma rays. The LD50 value was fixed at 15 kR for both varieties based on germination percentage. Progressive decreases in germination and survival with increase in gamma ray dose were recorded in the M1 generation. Stimulatory and inhibitory effects were noticed in quantitative characters with lower and higher doses, respectively. The mean expression and variability in quantitative characters increased considerably in the M2 generation. The different mutagenic treatments showed an inconsistent relationship with respect to mutagen mean and variability. However, considerable increase in variance was observed in traits such as plant height, seed yield per plant and oil content. Regarding seed yield per plant, heritability and genetic advance were maximum at 20 kR and 5 kR in the genotypes Morden and CO 4, respectively. [ABSTRACT FROM AUTHOR]

A several-year study of distribution, phytocoenological differentiation, floristic composition and structure of ruderal flora and vegetation and relevant anthropogenic influence was conducted at Pančevački Rit in Serbia. Ten clearly distinctive ruderal communities were identified in the study, including the newly formed community Matricario-Helianthetum annuae. This community is a unique combination of transitional ruderal and agrestal vegetation developing spontaneously in close vicinity of intensively cultivated agricultural fields, in which sunflower (Helianthus annuus L.), an annual crop, appears and persists subspontaneously and often massively, rendering a physiognomical character to ruderal habitats in which ephemeral ruderal weed vegetation often develops, consisting predominantly of annual plants of Sisymbrion officinalis R.Tx., Lohm. et Prsg.1950. [ABSTRACT FROM AUTHOR]

A novel variant devoid of rayflorets was identified in the interspecific derivatives of the cross between cultivated sunflower and H. divaricatus. The outermost whorl of the capitulum was comprised of modified disc florets which had longer petals than the regular disc florets and were hermaphrodite unlike the ray florets which are unisexual with non-functional stigmas. Inheritance studies indicated that the apetalous trait is under monogenic recessive gene control. Utility of the trait in physiological and breeding studies is under investigation. [ABSTRACT FROM AUTHOR]

This report presents the current knowledge of Orobanche resistance in sunflower from the breeder's standpoint and from the biochemists' standpoint. The parasitic relations in Helianthus annuus / Orobanche cumana associations differ in many respect from relations of other Orobanche spp. and their hosts. A major difficulty for the breeder is the fast development of new pathotypes of Orobanche cumana, which overcome the resistance of newly developed sunflower lines. The basis of increasing aggressiveness of Orobanche cumana pathotypes is discussed. Nevertheless, there is still large potential for resistance breeding in the genus Helianthus, since very different resistance factors are already known or shall be elucidated. A survey is presented of known resistance factors, such as low stimulants, mechanical barriers and how they develop, phytoalexins, Orobanche seed germination inhibitors, inhibition of exoenzymes of the Orobanche radicles, in particular of polygalacturonase, which enables the penetration of Orobanche tissue into the host root along the middle lamellae. In this context an interesting new approach may be found in the polygalacturonase-inhibiting proteins occurring in cell walls, which inhibit the invasion of pathogenic fungi. The need for molecular biological studies will be stressed. Interdisciplinary collaboration of breeders with biochemists and molecular biologists may lead to more advanced breeding strategies. [ABSTRACT FROM AUTHOR]

Amongst the diseases on the cultivated sunflower (Helianthus annuus L.) in India, the downy mildew disease caused by the fungus Plasmopara halstedii (Farl.) Berl. & De Toni is counted as important one. The disease is quite destructive as it is seed-borne and there are large chances for its fast spread to other sunflower growing localities. Use of resistant hybrids/varieties appears to be the only way to combat the disease. During the kharif season of 2005-2006, 21 newly developed hybrids and 10 varieties were included in Initial Hybrid Trial (IHT), Advanced Hybrid Trial (AHT) and Initial/Advanced Variety Trial (I/AVT) within the framework of All- India Coordinated Program and were screened for downy mildew disease reaction. The hybrids/varieties were tested under high disease pressure in downy mildew infected plots at Oilseeds Research Station, Latur (M.S.), India. The data revealed that almost all newly developed varieties were susceptible to the disease. However, five hybrids, NSH-23, Sunbred-2077, NSSH-303, K-678 and MLSFH-93, were totally free from downy mildew incidence. Such hybrids can be exploited for commercial use. [ABSTRACT FROM AUTHOR]

Wild species of sunflower (Helianthus annuus) play an important role in the genetic improvement of this oleaginous crop since they have different characters of economic importance to be transferred into the cultivated form using interespecific hybridization. The purpose of our present research program is to preserve and characterize the genetic resources of both naturalized and exotic wild sunflowers having an agronomic interest. One of the first steps was to describe different accessions of annual wild species for biotic stress in order to detect potential resistance sources. H. petiolaris is one of the wild sunflower species that can be found in Argentina and we had selected before a certain number of these species on the basis of their Sclerotinia sclerotiorum responses on leaves and stems. This genetic material was then inoculated on leaves and stems but with Phomopsis helianthi, a fungus which produce stem canker in sunflower. This work shows the variability of brown necrotic responses after Phomopsis inoculations on H. petiolaris leaves and stems. Some half-sib families were detected to have good disease tolerance to Phomopsis as well as Sclerotinia and they will be backcrossed in order to increase the diversity for this disease resistance in the cultivated germplasm. [ABSTRACT FROM AUTHOR]

The cultivated sunflower (Helianthus annuus L.) is one of most important oil crops of the world. Although sunflower is primarily grown for extraction of its seed oil there is a limited production of non-oilseed sunflower types which are used in confections industry or as bird feed. The objective of this research was development of hybrids with high and stable oleic acid content and modified tocopherol composition, with high values for the two most important agronomic characters (seed yield and oil yield) and high tolerance to Phomopsis. The incorporation of the gene Ol+tph1 into these genotypes has led to the development of high-oleic hybrids with altered tocopherol profiles. Oil of these hybrids has a much longer shelf-life than standard sunflower oil. The process of incorporating the genes Ol+tph2 and Ol+tph1tph2 into highly productive sunflower genotypes is under way. The most important results of this line of research are the newly developed female lines with the oleic acid content in oil over 90% and the male lines (restorers) with an oleic acid content in the 89-93% range. Using these lines, hybrids will be developed whose oleic acid content in oil will exceed 90%. [ABSTRACT FROM AUTHOR]

Twenty-nine populations of five wild annual sunflower species (H. annuus, H. petiolaris, H. argophyllus, H. praecox, H. debilis and H. neglectus) were screened for resistance to Plasmopara halstedii by the whole seed immersion method. Resistant populations were then crossed with cultivated sunflower. Analysis of meiosis and pollen viability in parent and F1 populations was used for characterization of F1 interspecific hybrids, as self-fertilization can also occur. Resistant plants were found in the populations of the species H. annuus and H. argophyllus. The percent of resistant plants in H. annuus populations was 9.09-100% and in H. argophyllus 50.00-57.14%. Irregular chromosome pairing in diakinesis was found in 0-20.83% of meiocytes of the F1 interspecific hybrids, with quadri- and univalents present. Pollen viability of male fertile interspecific hybrid plants was 10.21-98.85% in H. annuus and 39.90-52.47% in H. argophyllus. The obtained results suggest that annual wild sunflower species can be used to obtain resistance, or at least to increase the tolerance of cultivated lines to Plasmopara halstedii. [ABSTRACT FROM AUTHOR]

Significant manifestation of heterosis for agronomically important traits is the main precondition for obtaining productive sunflower hybrids (Škorić et al., 2006). Development of high-yielding and stable sunflower hybrids based on interspecific hybridization requires knowledge of heterotic effects occurring in the F1 generation. Heterosis for seed yield per plant, total seed number per head and 1,000-seed weight was studied in interspecific hybrids obtained by the line x tester method. The seven female inbred lines used in the study had been developed by interspecific hybridization, while the three male restorer inbreds with good combining abilities were used as testers in the form of fertility restorers. Twenty-one F1 hybrids were obtained by crossing each tester with each female inbred line. A trial with the lines and F1 hybrids was set up at Rimski Šancevi. Experiment Field of Institute of Field and Vegetable Crops in Novi Sad using a randomized block design with three replications. Our study found significant differences in the mean values of all the traits under investigation. Heterosis values for seed yield were positive and highly significant relative to parental average (98.4-274.1%) as well as better parent (55.8-223.2%). Considerably less heterosis was found for total seed number per head (69.6-203.7%) relative to parental average and better parent (47.6-183.3%). With 1,000-seed mass, the values ranged between 26.5% and 48.8% relative to parental average and from -42.4% to 30.9% relative to better parent. This study could prove useful in the development of new high-yielding sunflower hybrids based on interspecific hybridization. [ABSTRACT FROM AUTHOR]