The argentine wild Helianthus annuus L. genetic resource

CANTAMUTTO, MIGUEL; POVERENE, MÓNICA; PRESOTTO, ALEJANDRO; ALVAREZ, DANIEL; LENARDÓN, SERGIO; RODRIGUEZ, RAÚL; MARTIN-SANCHEZ, J; FERNANDEZ-MORONI, IVANA; GIOLITTI, FABIAN; GARAYALDE, ANTONIO; HAUCKE, ALEJANDRO; BELLIDO, ANDRÉS; FRAYSSE, MATÍAS

Antalya, Turquía

Conferencia; 8th European Sunflower Biotechnology Conference; 2010

Wild Helianthus annuus from Argentina provides resistant genes for Puccinia heliantii tolerant sunflower varieties released by the middle of the past century. Naturalized wild populations currently located between S 32.0° to S 37.2° latitude could be a valuable genetic resource to sunflower crop. To test this hypothesis, five wild populations were selected with the aim of represent different original environments and phenotype expression in a common garden study. Their plants showed normal chromosome behavior at diakinesis. Two of those populations normally fertilized (> 70 %) the CMS PET1 A09 inbred line when pollen was applied daily. Fruit set was reduced (< 30 %) with one accession, collected in the more humid environment when pollen was applied at a three-day frequency. Another accession, collected in the driest environment, showed high fruit set (> 60 %) without differences with DK4000 at three-day pollination interval. All wild populations restored more than 80% fertility of CMS PET1 HA89 and CMS PET1 A10 inbred lines at F1 generation, but none of them restored the CMS RES1 HA89, with H. resinosus cytoplasm. The fertility of a male sterile source from Las Malvinas population was partially restored (66%) by RHA274 inbred line, but the restorers RPET2, R49, R432 and R307 failed to produce more than 10% of fertile progenies at F1 generation. Male fertility restoration over 95% was obtained using pollen of the maintainer line B10.  The fatty acid composition evaluated in a common garden study differenced one population from Entre Ríos, with saturated fatty acid content over 107 g kg-1. Another population from La Pampa, with probable introgression of H. petiolaris, showed high level (> 50%) of resistance to Sunflower chlorotic mottle virus (SuCMoV). The five wild populations did not show tolerance to imazaphyr sprayed at 4-6 leaf stage at 2 X doses (160g i.a. ha-1). The population colleted in the southern and coolest point of the geographic distribution of wild sunflowers, showed high tolerance to low temperature (15/5°C, neutral day) at initial grow stages (< 3 expanded leaves). Eleven morpho-physiological traits differenced the wild populations in their response to water stress. A population from Córdoba province, collected in a dry and hot habitat, with an overall good performance to drought, showed the higher germination (> 80%) under water stress (-0.4 MPa) imposed by polyethylen glycol 6000. This population and another from southern Buenos Aires showed the lowest leaf temperature increase (< 10 %) and the highest foliar specific density under water limitations (irrigation covering 50% of potential air demand) during R4 to R6 reproductive stages. It could be concluded that wild H. annuus naturalized in central Argentina can supply some useful traits for sunflower breeding.