Tags

Type your tag names separated by a space and hit enter

Homothallic sexual reproduction of Pustula helianthicola and germination of oospores.
Fungal Biol 2012; 116(9):976-84FB

Abstract

Sunflower white blister rust has become an important disease in many countries with intensive cultivation of the important oil crop. The biology of the pathogen is still partly unclear, particular with respect to its sexual reproduction and primary mode of infection. Zoospores released from sporangia of Pustula helianthicola were isolated individually and used for the inoculation of sunflower in order to generate unithallic, genetically homogenous infections. Single zoospore inoculation of young seedlings resulted in mitotic sporulation within subepidermal blisters on cotyledons and true leaves after approximately 2 weeks. Three weeks postinoculation, the infected plants started forming oospores, hence indicating homothallic sexual reproduction of the pathogen. The development of oogonia and antheridia was studied using light and fluorescence microscopy. Oospores were isolated from infected plant tissue and used for infection and germination studies. Microscopic observation of isolated oospores showed germination that formed sessile vesicle-like structures, germ sporangia or only germ tubes. The rate of germination reached approximately 40 %. Germination was not dependant on a resting phase after oospore formation. Oospores applied to the above ground parts of sunflower seedlings lead to infections within a similar time frame as was achieved with mitotic sporangia. The results underline the importance of oospores for primary infection at the beginning of the season and for long-distance dispersal of the pathogen with sunflower seeds contaminated by oospores.

Authors+Show Affiliations

Institute of Botany, University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany.No affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

22954340

Citation

Lava, Sukanya Soonagahalli, and Otmar Spring. "Homothallic Sexual Reproduction of Pustula Helianthicola and Germination of Oospores." Fungal Biology, vol. 116, no. 9, 2012, pp. 976-84.
Lava SS, Spring O. Homothallic sexual reproduction of Pustula helianthicola and germination of oospores. Fungal Biol. 2012;116(9):976-84.
Lava, S. S., & Spring, O. (2012). Homothallic sexual reproduction of Pustula helianthicola and germination of oospores. Fungal Biology, 116(9), pp. 976-84. doi:10.1016/j.funbio.2012.06.007.
Lava SS, Spring O. Homothallic Sexual Reproduction of Pustula Helianthicola and Germination of Oospores. Fungal Biol. 2012;116(9):976-84. PubMed PMID: 22954340.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Homothallic sexual reproduction of Pustula helianthicola and germination of oospores. AU - Lava,Sukanya Soonagahalli, AU - Spring,Otmar, Y1 - 2012/07/07/ PY - 2011/07/20/received PY - 2012/05/25/revised PY - 2012/06/28/accepted PY - 2012/9/8/entrez PY - 2012/9/8/pubmed PY - 2013/1/17/medline SP - 976 EP - 84 JF - Fungal biology JO - Fungal Biol VL - 116 IS - 9 N2 - Sunflower white blister rust has become an important disease in many countries with intensive cultivation of the important oil crop. The biology of the pathogen is still partly unclear, particular with respect to its sexual reproduction and primary mode of infection. Zoospores released from sporangia of Pustula helianthicola were isolated individually and used for the inoculation of sunflower in order to generate unithallic, genetically homogenous infections. Single zoospore inoculation of young seedlings resulted in mitotic sporulation within subepidermal blisters on cotyledons and true leaves after approximately 2 weeks. Three weeks postinoculation, the infected plants started forming oospores, hence indicating homothallic sexual reproduction of the pathogen. The development of oogonia and antheridia was studied using light and fluorescence microscopy. Oospores were isolated from infected plant tissue and used for infection and germination studies. Microscopic observation of isolated oospores showed germination that formed sessile vesicle-like structures, germ sporangia or only germ tubes. The rate of germination reached approximately 40 %. Germination was not dependant on a resting phase after oospore formation. Oospores applied to the above ground parts of sunflower seedlings lead to infections within a similar time frame as was achieved with mitotic sporangia. The results underline the importance of oospores for primary infection at the beginning of the season and for long-distance dispersal of the pathogen with sunflower seeds contaminated by oospores. SN - 1878-6146 UR - https://www.unboundmedicine.com/medline/citation/22954340/Homothallic_sexual_reproduction_of_Pustula_helianthicola_and_germination_of_oospores_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1878-6146(12)00119-5 DB - PRIME DP - Unbound Medicine ER -