The structure of mating type, virulence, metalaxyl resistance of Phytophthora infestans in a long-term phenotypic study in distinct location in Eastern Estonia

The population of Phytophthora infestans in Brazil was first characterized 12 years ago. In this research, isolates of P. infestans from potato (n = 184) and tomato (n = 267) collected in southern and southeastern Brazil were characterized to provide more detailed analysis of the current structure of the population. All 451 isolates were analyzed for mating type, and subsets of the isolates were analyzed for allozymes, restriction fragment length polymorphism fingerprint, mtDNA haplotypes, and metalaxyl resistance. Tomato isolates were all of A1 mating type, mtDNA Ib, and US-1 genotype or some variant within this clonal lineage. Of the potato isolates, 82% were A2 mating type, mtDNA IIa, BR-1 genotype, which is a new lineage of P. infestans. All A2 isolates were found on potato, whereas 91% of the A1 isolates were from tomato. A1 and A2 isolates were never found in the same field. The frequency of resistance to metalaxyl was higher in isolates from tomato (55%) than in isolates from potato (38%). After more than a decade of coexistence of isolates of the A1 and A2 mating types, the population was highly clonal, dominated by the BR-1 and US-1 clonal lineages.

Download Full-text

The structure of mating type, metalaxyl resistance and virulence of Phytophthora infestans isolates collected from Latvia

Zemdirbyste-Agriculture ◽

10.13080/z-a.2015.102.043 ◽

2015 ◽

Vol 102 (3) ◽

pp. 335-342 ◽

Cited By ~ 7

Author(s):

Alice Aav ◽

Ilze Skrabule ◽

Gunita Bimšteine ◽

Tanel Kaart ◽

Ingrid H. Williams ◽

...

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Metalaxyl Resistance

Download Full-text

Mating type, Metalaxyl Resistance and Aggressiveness of Phytophthora infestans (Mont.) de Bary in Morocco

Journal of Phytopathology ◽

10.1046/j.1439-0434.2002.00736.x ◽

2002 ◽

Vol 150 (4-5) ◽

pp. 289-291 ◽

Cited By ~ 5

Author(s):

A. HAMMI ◽

Y. MSATEF ◽

A. BENNANI ◽

A. E. L. ISMAILI ◽

M. N. SERRHINI

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Metalaxyl Resistance

Download Full-text

Variation in populations of Phytophthora infestans in Finland and Norway: mating type, metalaxyl resistance and virulence phenotype

Plant Pathology ◽

10.1046/j.1365-3059.2000.00426.x ◽

2000 ◽

Vol 49 (1) ◽

pp. 11-22 ◽

Cited By ~ 56

Author(s):

Hermansen ◽

Hannukkala ◽

Hafskjold Naerstad ◽

Brurberg

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Metalaxyl Resistance ◽

Virulence Phenotype

Download Full-text

Determination of Mating Type of Phytophthora Infestans and Long Term Preservation by Using Mineral Oil

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.108.132 ◽

2011 ◽

Vol 108 ◽

pp. 132-137

Author(s):

Xin Xin Li ◽

Sheng Jun Xu ◽

Xuan Zhe Zhang

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Mineral Oil ◽

North West ◽

Long Term Storage ◽

Preservation Method ◽

Fitness Index ◽

Long Term Preservation

Seventy six isolates of Phytophthora infestans from North-West China was determined for the mating type, and an effective preservation method using mineral oil was developed. All P. infestans isolated had A1-mating type. When the isolated were stored in mineral oil, 94.9% of P. infestans isolates were viable. The composite fitness index of P. infestans isolates preserved in mineral oil accounted for 14,806~119,935 sporangia per cm2, with 40,926 sporangia per cm2 for the average composite fitness index. All data suggest that mineral oil preservation for P. infestans can be an easy and efficient preservation method for long term storage of P. infestans without losing pathogenicity.

Download Full-text

Mating Type, Virulence, Aggressiveness and Metalaxyl Resistance of Isolates of Phytophthora Infestans in Poland

Potato Research ◽

10.1007/s11540-006-9013-2 ◽

2007 ◽

Vol 49 (3) ◽

pp. 155-166 ◽

Cited By ~ 17

Author(s):

Jadwiga Śliwka ◽

Sylwester Sobkowiak ◽

Renata Lebecka ◽

Jose Avendaño-Córcoles ◽

Ewa Zimnoch-Guzowska

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Metalaxyl Resistance

Download Full-text

First Report from Morocco of Phytophthora infestans Isolates with Metalaxyl Resistance

Plant Disease ◽

10.1094/pdis.1997.81.7.831d ◽

1997 ◽

Vol 81 (7) ◽

pp. 831-831 ◽

Cited By ~ 2

Author(s):

M. Sedegui ◽

R. B. Carroll ◽

A. L. Morehart ◽

A. Arifi ◽

R. Lakhdar

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Solanum Tuberosum L ◽

Relative Sensitivity ◽

Control Programs ◽

Growing Seasons ◽

Metalaxyl Resistance ◽

Commercial Potato ◽

Tomato Cultivars ◽

Allozyme Loci

Late blight of potato (Solanum tuberosum L.) caused by Phytophthora infestans (Mont.) de Bary first appeared in Africa in 1941. It has been observed sporadically in Morocco for decades but only recently became a major problem. Significant losses have been recorded in the last two growing seasons in spite of the use of various disease control programs that included combinations of systemic and protectant fungicides. Phytophthora infestans was cultured from diseased foliage collected from commercial potato fields near Larache, Morocco. Isolates were analyzed to determine pathogenicity on several potato and tomato cultivars, mating type, genotype at two allozyme loci (2), and relative sensitivity to metalaxyl. Responses of the isolates to metalaxyl were assayed by mycelial radial growth on metalaxyl-amended agar, by floating leaves inoculated with P. infestans on metalaxyl solutions, and via potato tuber disks placed on filter paper saturated with metalaxyl solutions (1). Koch's postulates were completed; all isolates were pathogenic to potato and tomato cultivars tested, are consistent with the A1 mating type, and have the same allozyme pattern (Gpi 100/100, Pep 92/100) as US-6 genotype. All tests indicated resistance to metalaxyl up to 250 ppm. References: (1) K. L. Deahl et al. Am. Potato J. 70:779, 1993. (2) S. B. Goodwin et al. Plant Dis. 79:1181, 1995.

Download Full-text