Leaf extracts from 17 Helianthus annus lines and 18 wild Helianthus species were analyzed by thin-layer chromatography with cellulose-coated plates for variation in phenolic compounds. There was no qualitative variation among the cultivated lines. In the wild species, H. tuberosu and H. laciniarus frequently showed yellow fluorescing components, probably flavonoid compounds, while the two H. occidcntalis accessions and one H. mollis accession were distinguished by a pale blue fluorescing phenolic compound.

Isozyme (eight loci), tocopherol (two genes), and fatty acid (one gene) phenotypes are shown to be a suitable seed biochemical marker of genetic purity in sunflower. Isoryme loci Est 1, Gdh 1, Gpi 1, Mdh 2, Mdh 5, Pgd 1, and Pgn 4 have an independent inheritance with Tph 1 and Tph 2 genes, controlling tocopherol composition, and Est 1 and Pgd 1 loci - with Ol 1 gene, controlling the oleicflinoleic ratio in seed oil. Fourteen inbred lines of sunflower were identified with these biochemical markers.

Genotypic variation in yield under rainfed conditions and at a given level of evapotranspiration is mainly attributed to differences in dry matter produced per unit amount of water (Water Use Efficiency-WUE). WUE measured at the single leaf level by gas exchange techniques àrrelate well with that measured by the gravimetric method. WUE can be improved by either increasing the photosynthetic rate at a given stomâtal conductance or by decreasing the stomatal conductânce. Across species, photosynthetic rate is determined by the carboxylâtion efficiency at a given internal CO2 concentration. Carborylation efficiency in sunflower genotypes is mainly regulated by the efficiency of RuBisCO (A/RuBisCo). Selection of genotypes with efficient RuBisCO leads to increased photosynthetic rate and hence to higher WUE. We conclude that improvement of carboxylation efficiency could form an important strategy in increasing WUE and thereby the productivity both under rainfed and irrigated conditions.

Two sunflower lines possessing two different types of sunflower branching and one line of a non-branching type were included in the study. The aim of the study has been to find the mode of inheritance of branching. According to the results produced, the different types of branching are controlled by different genes in different positions. The non-branching type âppears as prevailing. This result favours the use of branching as a basis for fertility restorer lines in hybrid seed production.

A male sterile plant was observed in a sunflower (Helinnthus annus L) population raised from a 12-day-old immature embryo culture of cultivar Modern. This plant was crossed with the parental line. The Ft was fertile and the F2 segregated in the ratio of 3 fertile: 1 sterile, indicating that male sterility was governed by a single recessive nuclear gene. The monogenic recessive nature was confirmed by a test cross, where it segregated in the ratio of 1 fertile: L sterile. With the Cultivar Modern, being early and dwarf, male sterility could be effectively exploited for developing early, dwarf, and semidwarf lines/hybrids.

Se cultivaron embriones cig6ticos Fz rescatados entre 9 y 15 días posteriores a la polinización sobre un medio MS modificado. Los porcentajes de germinación fluctuaron entre O y 96Vo respectivamente, no encontrándose diferencias genotípicas. Se evaluaron 3 tratamientos de rustificación previo al transplante a tierra resultando superior aquel en que se utilizaron plantas con un solo par de hojas (mantenidas durante 48-72 horas en agua en un cuatro climatiza 26 + 2). Las plantas regeneradas manifestaron una reducción en la altura y en el diámetro del capítulo, no significando esto un inconveniente en la aplicación del método SSD para la obtención de líneas.

Five Azotobacter and seven phosphate-solubilizing fungi were isolated from sunflower rhizosphere identified, screened for their nitrogen fixation and phosphate solubilisting efficiency. Azotobacher cuultures did not inhibity any fungi; on the other hand, all fungal cultures suppressed the growth of Azotobacter, except three Penicillum cultures (H.F-3,4 and5). Azotobacter cultures GA2 and GA3 increased seed germination but the other three did not. All Azotobacter cultures increased radicale/plumule lenght significantly except GA-1 where it reduced the radicle lenght by 13.6 percent over the control. All fungal cultures showed high deleterious effect on seed germination as well as on radicle/plumule growth as compared with the control. The combined growth Azotobacter cultures(GA-1 and GA-3) with Penicillum (HF-4 &5) and Aspergillus (GF-1 and2) species increased the lenght of both radicle and plumule but the culture combinations decreased the lenght of both radicle and plumule over the control.

The objectives of this study were: (a) to quantify yield losses of plants under natural conditions of infection by Sclerofinia mid-stalk rot, and (b) to determine if there is any relation between the magnitude of such losses and the length of the lesion caused by the disease. Mid-stalk rot infected plants (N:120) showed an average reduction of 357 % in seed field, a lower number of seeds per head (?AVo); a decrease in 1000-seed weight (15%) and lower oil percent (8.1 points) as compared with healthy control plânts (p<0.0001). The reductions in seed yield, seed number, seed weight, and oil content in seed were very significantly correlated with the lesion length of the mid-stalk rot-infected plants. I-,esion length can be utilized as a predictor of such decreases and as a valuable tool in screening genetic materials for tolerance to this disease.

Experiments were carried out at the University of Agricultural Sciences, Bangalore, during L993, to screen the germplasm lines with high dry matter production to achieve higher seed yields since total dry matter prôduction (fDM) was shown to have a positive effect on seed yield in sunflower. Significant genotypic variations for leaf area index (I-AI) at flowering, assimilation rates (DMÂ-AD or DM/I-A), TDM, and seed yield and harvest index were observed both in summer and rainy season. Certain genotypes (Acc 1630, Acc 1.603, Acc 421, etc.), which possess high TDM, also had higher seed yields and higher l-AI or assimilation rates. A correlation study again confirmed that the TDM had a direct and significant effect on seed yield. The TDM or seed yield, which is indirectly influenced by l-AI or assimilation rate, was also found to be positively correlated. Therefore, selection of genotypes such as ACC 1630, ACC 1603, ACC 421, etc., which have high assimilation rates with high LAlmay, further increase the yield when used in breeding programmes.

In different planting designs of parent lines for hybrid seed production, pollen is provided by the fertility-restoring line. Apis rnellifoa L. is the most important insect in pollen transfer from the inflorescences of the male line to those of the female. In 1989-1991, in the Dobrudja region, Bulgaria, studies were conducted to determine the row spacing effect of the female line rows of Albena hybrid from the male line row on the density of Apis mellifera L. on the rows of the female line. The results of the investigation show that on an average day, when the density oflP6 mellilera is from 6 to 40 bees per 100 heads, there is no correlation between the traits studied, i.e., the row spacing between the sunflower self-potlinated line 2607 and the male line, in a planting design 5:1 ofhybrid seed production, does not affect the density of Apis mellilera L. on these rows.

This research was conducted to evaluate a mixture of dry powder formulations of Apron and captan on percent pure live seed (P15) emergence and emergence index (EI) in sunflower (Helianthus annuus L.) and safflower (Carthamus tinctoious L.) seed lots of varying vigor levels. Treatments were evaluated in the field ând in a growth chamber using the cold soil test. Results indicated that PLS emergence of the low-vigor seed lots of both crops increased due to fungicide treatment to a higher degree than did high-vigor seed lots. Percent PI-S emergence in the field and the growth chamber for each crop was significantly (P < 0.05 or P<0.1) correlated. This suggests that seed treatment is important in stand establishment for low vigor seed lots due to its protective effect âgainst seed and soil-borne microorganisms

This research was conducted to evaluate adenosine monophosphate seed treatment on seedling emergence and emergence index (EI) in sunflower (Helianthus annuus L.) and safflower (Carthamus tinctoious L.) seed lots of varying vigor levels. Treatments were evaluated in the field and in the laboratory. Results indicated that the percent PIS emergence of both crops in the field was influenced significantly (P<0.01) by the adenosine monophosphate seed treatment. This suggests that seed treatment with adenosine monophosphate may improve the seedling growth rate of low-vigor seed lots under low temperature ( < 10 C) stress.

The experiments of the ninth international cycle were conducted by 11 governmental research institutions or private companies from 9 countries covering the main sunflower cropping area in Europe and North America. A great variation with respect to the environmental adaptability, genetic yield potential, and oil content was registered in the ninth biennial cycle of international trials with sunflower hybrids. An important group of hybrids exhibited a satisfactory stability over a multitude of locations in both experimental years, while certain hybrids were better differentiated only within limited areas. A good behaviour was shown by the hybrids HOGGAR, P-6541 PIONN, SANKARA, and HU-GKI-43.

This report presents research accomplishments of the working group for the valuation of wild Helianthus species since the last progress report at the FAO meeting in 1991 at Pisa, Italy. The working group conducted broad and extensive investigations on the wild species with a common goal to increase the genetic diversity of cultivâted sunflower using wild species to make it better global croP. The accomplishmènts of the working group have added new data on exploration and maintenance and characterization of wild sunflower species, germination and dormancy, phyto-genetics and classification of Helianthus, interspecific hybridization, rytogenetics of species ànâ interspecific hybrids, cytoplasmic male sterility and fertility restoration, oil quality and protein content, drought tolerance, disease resistance and regeneration of wild Helianthus ipecies, and this way they added considerable knowledge to informational datâbase about the wild sunflower species and their potential use in improving cultivated sunflower.

DuetoparticularlyactiveworkdevelopedintheCMS.workinggroupbymostofthe participants, interesting results have been got. The most significânt contributions were:- The discovery of the CMS sources- The finding of restorer genes for "difficult to restore" CMS- The analysis of the genetic determinism of the fertility restoration of new CMS. _ The comparison of ihe cMS by genetic, molecular, or agronomical ways. Therefore, evidence is that a lot of studies are still necessary to differentiate the CMS sources. I-itay, some of the 42 cMS sources reported may be identical. It is clear that complementary genetic studies have to be performed. Molecular studies on Mt DNd proved to bË powerfuliJob and fast techniques, either to separate the CMS or to explain the mechanisms of the cytoplasmic male sterility. Another aspect to be studied is the identification of the specific Rf genes in the different cMs. With this objective, several participants have already started crosses between restorer genotypes to prepare allelism tests. Ttrii could be one of the proposals of the w. G., for the next period.