Due to a specific structure of its main organs (root, stem, leaves, head), sunflower can be successfully grown on marginal soils and in semi-arid condi tions and it is more resistant to abiotic stresses than other field crops. In sun flower breeding for resistance to abiotic stresses, the greatest progress has been made in selection for drought resistance. Breeders use over 30 different parameters in sunflower screening for drought resistance, with physiological ones being the predominant type. Best breeding results have been achieved using the phenomenon of stay-green, with the added bonus that this method incorporates into the cultivated sunflower not only drought resistance but resistance to Macrophomina and Phomopsis as well. The diversity of the wild Helianthus species offers great possibilities for increasing the genetic resist ance of the cultivated sunflower towards abiotic stresses. In using wild sun flower species in sunflower breeding for drought resistance and resistance to salinity, best results have so far been achieved with H. argophyllus and H. paradoxus, respectively. In addition to the use of wild Helianthus species, sun flower breeding for abiotic stress resistance should also make more use of molecular breeding techniques. More progress has been made in sunflower breeding for heat resistance than in that for cold resistance. Specific breeding programs dealing with sunflower resistance to mineral deficiency and mineral toxicity have yet to be established. Sunflower breeders worldwide should com mit to a greater use of wild Helianthus species in breeding for resistance to abiotic stresses.

Seed morphology and disk diameter are agronomically most important traits for the confection sunflower. This paper reports the results of an analy sis 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 dis tance 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 pheno typic 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 sun flower breeding.

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 Agricul ture 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, reveal ing 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.

Disc flowers of Helianthus petiolaris (Asteraceae) are usually purple red due to anthocyanin pigments in corolla lobes, style and stigma. However, yel low-flowered plants are occasionally found. The inheritance of this trait was studied through crosses between different phenotypes and the results indi cated that flower color is controlled by two genes with complementary action, both loci being dominant and independently inherited. This agrees with results obtained in cultivated sunflower, H. annuus, where one to three dominant genes have been proposed for anthocyanin expression in different organs.

White rot is an important disease of sunflowers. Sunflower genotypic responses to S. sclerotiorum have to be evaluated with precision. White rot disease could be assessed by components of partial resistance and this would help to evaluate accurately genotypic responses. Here we wish to show which of variables or components of white rot are most suitable for describing sun flower performance during disease cycle. Twelve sunflower genotypes have been grown in an experiment and then inoculated. Disease incidence, relative incubation period, disease severity (observed at two moments), and the growth lesion rate were scored. All variables showed variability among the genotypes. The disease incidence and relative incubation period were confirmed as com ponents of partial resistance. The results also indicated that the growth lesion rate during the intermediate and last phases of the disease seemed most appropriate to be used simultaneously with disease incidence and relative incubation period. If these three components were selected simultaneously, developed cultivars would have a more complex resistance and they would be less prone to the disease.

A total of seven Acaulospora species (Acaulospora laevis, A. lacunose, A. rehmii, A. foveata, A. gerdemanniii, A. bireticulata, A. scrobiculata) isolated from sunflower rhizosphere are described and illustrated. A key to species of Acaulospora genus has also been prepared on the basis of their morphological characters. Spores of these species have been identified by morphological characters such as hyphal attachment if any, spore ornamentation, wall layers and spore color and size.

The present investigation was aimed at analyzing the role of fumigants, i.e., different concentrations of carbon disulphide (CS2) and formalin, on soil mycoflora including mycorrhizal fungi in the sunflower rhizosphere. Fungi were greatly reduced immediately after fumigant application but with the pas sage of time these started to reappear. In qualitative analyses of mycoflora, Aspergillus niger, Aspergillus terreus and Penicillium nigricans reappeared only after 20 days at all CS2 concentrations. The quantitative study showed the boosting up of the population of Trichoderma viride with increasing concentra tions of formalin and CS2 after 20 days. High concentrations of both fumigants initially decreased mycorrhizal spore number. However, the mycorrhizal spore number increased later on. Mycorrhizal root colonization reached maximum after 40 days in treated soils. Glomus mosseae was resistant to CS2 applica tion but Glomus geosporum and Acaulospora laevis were inhibited by high concentrations of the fumigant.

Isolates of P. halstedii collected from different parts of Karnataka, Maharashtra and Andhra Pradesh belong to a single race, i.e., race 100. Based on virulence pattern, they can be grouped into five different groups, A, B, C, D and E. Bangalore isolate was most virulent and Bidar isolate was least virulent. Morphological variations existed among the isolates with regard to the size of sporangiophores and sporangia. Sporangiophores were longer Dharwad iso late and sporangia were larger in Mysore and Latur isolates.

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 find ing 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 con ventional 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.

As many as 251 insect and acarid species are known to attack sunflower crop worldwide. Recently, a stem borer has emerged as a new and regular pest of sunflower in Marathwada region (M.S.) India. It is a coleopterous grub Nupserha sp. near vexator (Pascoe), which belongs to the family Cerambyci dae: Lamiinae. Hence, the screening of sunflower germplasm lines was con ducted during last five years to identify resistance sources against stem borer for further exploitation in breeding programs. A set of 100 germplasm lines was annually received from All-India Coordinated Research Project on Sunflower during 2002-2006 to evaluate sources of resistance for major sunflower pests. The screening work was carried out at Oilseeds Research Station, Latur, M.S., India, which was identified as a hotspot for stem borer in sunflower. Reactions to stem borer received from the germplasm lines were categorized for ease in evaluation of resistance potential of each test line. Stem borer inci dence varied from free to >80% in the germplasm under investigation during last five years indicating the presence of adequate variability in the material for their response to stem borer infestation.

Of the different integrated seed treatment options tested for the manage ment of Alternaria blight of sunflower, highest benefit was obtained in the seed treatment with Carbendazim+Iprodione (Quintal) at 0.3% in water along with hexaconazole foliar spray (0.1%) followed by seed treatment with Pseu domonas fluorescens (0.8%) in jelly+hexaconazole foliar spray. Efficacy of Pseudomonas fluorescens as seed dresser can be enhanced by bio-priming the sunflower seeds for the effective and eco-friendly management of Alternaria blight of sunflower.

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

An experiment was conducted to determine the effects of the ratio of leaf removal from bottom of plants (0, 4, 8 and 12 leaves/plant) shortly before flow ering on yield components and some quality characters of sunflower ecotypes. According to ecotype averages, seed setting, seed yield, kernel ratio, crude oil and crude protein contents in seed, crude oil yield and crude protein yield changed with different degree of leaf removal. Head diameter, seed setting, seed yield, 1000-seed weight, kernel ratio, crude oil, crude protein content, crude oil yield and crude protein yield varied with degree of leaf defoliation of some ecotypes while these characters were not affected by defoliation in other ecotypes.

The effect of storage on biochemical composition of seeds located in dif ferent whorls of sunflower head at maturity has been studied. The proportion of filled seeds, yield parameters such as weight of seeds, kernels and oil per whorl and dry weight of seeds and kernels decreased from the peripheral towards the central whorls. Dry matter, oil and starch contents decreased after 180 days of storage at room temperature. The content of total soluble sugars increased while that of reducing sugars decreased in peripheral whorls from first to ninth positions during storage for 180 days. The storage of seeds located in central whorls lowered the proportion of oleic acid with a corre sponding increase in linoleic acid after 180 days. Thus, the seeds located in peripheral whorls were more productive and better for storage purposes than those in central whorls.

Sunflower is the world fourth most important source of edible oil, after palm oil, soybean and rapeseed/canola. Sunflower acreage in Brazil has been consolidated due to the constant efforts in genetic and agronomical studies carried out by Brazilian research institutions. Although easily adapted to many Brazilian regions, genetic and agronomical improvements were needed so that economically viable crops could be harvested. Sunflower varieties with inter esting oil composition as well as noteworthy protein quality were obtained. As part of these efforts, two new varieties were developed by Embrapa Soybean, Embrapa 122 V2000 and Embrapa F2 BRS 191. This work was aimed at eval uating the chemical composition of the seeds, defatted meal and oil quality of these varieties. The oil content varied from 44 to 52% in F2 BRS and from 36 to 47% in E 122. Linoleic (62-69%) and oleic (20-25%) were the major fatty acids in both varieties. The protein content of the defatted meal ranged from 28 to 32%. Slight differences were observed in amino acids profile, sterols and chlorogenic acid content.