Comparative genetic analysis of quantitative traits in sunflower (Helianthus annuus L.) 1. QTL involved in resistance to Sclerotinia sclerotiorum and Diaporthe helianthi

The relationship between Sclerotinia sclerotiorum, causal agent of wilt or basal stem rot of sunflower (Helianthus annuus L.), and its hyperparasite Coniothyrium minitans was investigated in a sunflower field naturally infested with the two organisms. Sclerotia of S. sclerotiorum were collected biweekly from roots and basal stems of wilted plants and analyzed for infection by the hyperparasite. The results showed that C. minitans parasitized and killed the sclerotia produced on the root surface. This hyperparasite continued to parasitize the pathogen inside the root and upwards into the base of the stem, thus infecting the sclerotia produced at these sites. By the end of the growing season, 59%, 76%, and 29% of sclerotia on the root surface, inside the root, and inside the stem, respectively, had been killed by the hyperparasite, while 4%, 9%, and 68% of the sclerotia at these locations were healthy. Death of the rest of the sclerotia was due to organisms other than C. minitans. The data also indicate that C. minitans is more effective in parasitizing sclerotia produced on or inside the root than those produced in the basal stem.

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Genetic analysis of pollen viability: an indicator of heat stress in sunflower (Helianthus annuus L.)

International Journal of Innovative Approaches in Agricultural Research ◽

10.29329/ijiaar.2017.100.5 ◽

2017 ◽

Vol 1 (1) ◽

pp. 40-50

Author(s):

Khuram Razaq ◽

◽

Saeed Rauf ◽

Muhammad Shahzad ◽

Ejaz Ashraf ◽

...

Keyword(s):

Heat Stress ◽

Genetic Analysis ◽

Helianthus Annuus ◽

Pollen Viability ◽

Helianthus Annuus L

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VARIABILITY OF Phomopsis POPULATIONS IN SUNFLOWER (Helianthus annuus L.) / VARIABILIDAD DE LAS POBLACIONES DE Phomopsis EN EL GIRASOL (Helianthus annuus L.) / VARIABILITÉ DES POPULATIONS DE Phomopsis CHEZ LE TOURNESOL (Helianthus annuus L.)

Helia ◽

10.1515/helia.2001.24.34.69 ◽

2001 ◽

Vol 24 (34) ◽

pp. 69-76 ◽

Cited By ~ 4

Author(s):

J. Vukojević ◽

M. Mihaljčević ◽

D. Franić-Mihajlović

Keyword(s):

Helianthus Annuus ◽

Geographic Distribution ◽

The Other ◽

Helianthus Annuus L ◽

Diaporthe Helianthi ◽

Wide Geographic Distribution ◽

Distribution In Europe

SUMMARY Various reports state that the sunflower disease, primarily caused by Diaporthe/Phomopsis helianthi Munt.-Cvet. et al., has a wide geographic distribution in Europe, USA, Argentina and Australia. Various Phomopsis isolates obtained during this investigation of the sunflower disease differed in conidial type (α, β, α and β). Phomopsis helianthi was the only isolate producing exclusively β-conidia and perithecia on debris (Diaporthe helianthi). The other Phomopsis isolates were saprobes on sunflower plants.

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The Infection Processes of Sclerotinia sclerotiorum in Basal Stem Tissue of a Susceptible Genotype of Helianthus annuus L.

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha4017317 ◽

2012 ◽

Vol 40 (1) ◽

pp. 143 ◽

Cited By ~ 1

Author(s):

Robab DAVAR ◽

Reza DARVISHZADEH ◽

Ahmad MAJD ◽

Ardashir KHARABIAN MASOULEH ◽

Yobert GHOSTA

Keyword(s):

Helianthus Annuus ◽

Sclerotinia Sclerotiorum ◽

Host Cells ◽

Post Inoculation ◽

Plant Surface ◽

Susceptible Genotype ◽

Helianthus Annuus L ◽

Fungal Hyphae ◽

Infection Processes ◽

Host Tissues

Sunflower, Helianthus annuus L., is a major oil seed crop widely cultivated throughout the globe. White mold, caused by necrotrophic pathogen Sclerotinia sclerotiorum (Lib.) de Bary, is a common and widespread pathogen of sunflower. The infection process of S. sclerotiorum was studied in the stem base of infected host tissues by light microscopy and Hemi-thin sectioning techniques. Host-pathogen interactions were examined at the plant surface and cellular level of a susceptible genotype (C146), 12, 24 and 48 h of post inoculation. The results showed that the appressoria were formed and the hyphal strands branched upon contact of pathogen with the host surface. Moreover a direct penetration of fungal hyphae was observed through the cuticle within 12h of inoculation. Microscopic observation of inoculated tissues after 24 hours revealed that fungal hyphae have developed both inter- and intra-cellular layer. Moreover, the fungal hyphae growth was incremental among and inside the host cells. The host cells were completely colonized by fungal mycelium 48 hour after inoculation, leading to a tissue collapse. The hyphae invaded the dead host tissues and emerged from the host tissue after extensive colonization. The present study has detailed the infection processes and pathogen development both at plant surface and inside the host tissues. The results of this study will be useful for engineering of disease-resistant genotypes and development of markers for screening pathogen resistance individuals.

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HETEROSIS IN TOP-CROSS HYBRIDS OF DIVERSE CYTOSTERILE SOURCES OF SUNFLOWER (Helianthus annuus L.) / HETEROSIS EN LOS HIBRIDOS TOP-CROSS DEL GIRASOL CREADOS DE DIVERSAS FUENTES CITOESTERILES / HÉTEROSIS DANS LES HYBRIDES TOP-CROSS DE TOURNESOL (Helianthus annuus L.) OBTENUS DE DIVERSES SOURCES CYTOSTÉRILES

Helia ◽

10.1515/helia.2001.24.34.25 ◽

2001 ◽

Vol 24 (34) ◽

pp. 25-34

Author(s):

M.P. Rajanna ◽

A. Seetharam ◽

K. Virupakshappa ◽

S. Ramesh

Keyword(s):

Helianthus Annuus ◽

Quantitative Traits ◽

Oil Content ◽

The Other ◽

Male Sterile ◽

Breeding Programs ◽

Helianthus Annuus L ◽

Standard Heterosis ◽

Helianthus Petiolaris ◽

Heterosis Breeding

SUMMARY Standard heterosis was estimated for eight quantitative traits in top-cross hybrids of three diverse cytoplasmic male sterile (CMS) sources of sunflower viz., Helianthus petiolaris (CMS-PET1), Helianthus petiolaris ssp. fallax (CMS-PEF1) and Helianthus annuus ssp. lenticularis (CMS-ANL2) maintained under different nuclear backgrounds. The top-cross hybrids were derived by crossing the above three CMS sources with 12 male parents in a line x tester design. Significant heterosis over two standard checks in the desirable direction was observed for all traits. All three sources under study advanced the maturity in most of the hybrids. CMS-PET1 was found to be the best compared with the other sources as far as oil content was concerned. Mean performance of the hybrids for achene yield and other economically important characteristics indicated that the hybrids derived in the cytoplasmic background of CMSANL2 were the best followed by CMS-PET1 and CMS-PEF1 suggesting that CMS diversification in heterosis breeding programs would be rewarding in sunflower.

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Tamaño óptimo de parcela e incidencia de la podredumbre blanca del capítulo del girasol en el sudeste bonaerense

Revista de la Facultad de Agronomía ◽

10.24215/16699513e005 ◽

2019 ◽

Vol 118 (1) ◽

pp. 44-51

Author(s):

M. Anabella Dinon ◽

Santiago Delgado ◽

Fernando Castaño

Keyword(s):

Helianthus Annuus ◽

Sclerotinia Sclerotiorum ◽

Helianthus Annuus L

Para conocer el tamaño de parcela que permita medir con eficiencia la incidencia de la Podredumbre blanca del capítulo-PBC de girasol (Helianthus annuus L.) se evaluó, en Balcarce, un par de híbridos en ensayos de uniformidad durante 2016 y 2017. Todos los capítulos de cada ensayo se inocularon con Sclerotinia sclerotiorum (Lib.) de Bary. Durante el primer año y para cada híbrido, se delinearon 165 parcelas mínimas, de un surco de 2m x 0,70m (=1,4m2). Mientras que en el segundo, la cantidad fue de 150. En cada una de esas parcelas básicas se registró la incidencia de PBC. Luego se generaron ocho tamaños más, combinando las parcelas mínimas adyacentes en distintos arreglos. El tamaño óptimo se señaló detectando el punto de máxima curvatura en gráficos que relacionaron el coeficiente de variación y los nueve tamaños de parcelas considerados. El análisis de varianza combinado sólo detectó efectos significativos de híbridos (H), años (A) y HxA sobre la incidencia de PBC. Los resultados obtenidos no permitieron señalar un único tamaño de parcela, dado que el óptimo dependió del nivel de resistencia del híbrido y del año de experimento. Así durante 2017, año más favorable a la enfermedad, el tamaño óptimo de parcela para los dos híbridos, resultó inferior que el señalado en 2016. Bajo las condiciones en que se desarrolló el experimento, el uso de parcelas de mayor superficie al señalado, no provocaría un incremento significativo en la fiabilidad de medición de la INC, por unidad de recursos utilizados.

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