scholarly journals First Report of Puccinia triticina (Leaf Rust) Race FBPT on Wheat in South Africa

Plant Disease ◽  
2014 ◽  
Vol 98 (7) ◽  
pp. 1001-1001 ◽  
Author(s):  
T. Terefe ◽  
B. Visser ◽  
L. Herselman ◽  
T. Selinga ◽  
Z. A. Pretorius
Keyword(s):  
South Africa ◽  
Single Gene ◽  
Puccinia Triticina ◽  
Triticum Aestivum L ◽  
Adult Plant ◽  
Western Cape ◽  
Breeding Lines ◽  
The North ◽  
Minimum Spanning Network ◽  
Infection Types

Eleven isolates of Puccinia triticina Erikss. collected from bread wheat (Triticum aestivum L.) in the Western Cape during the 2010 annual rust survey were pathotyped to a race not previously recorded in South Africa. Replicated race analysis on seedlings of 16 Thatcher (Tc) near-isogenic differential lines at two rust laboratories confirmed avirulence (infection types [ITs] 0; to 2+) for lines with Lr1, Lr2a, Lr9, Lr11, Lr16, Lr24, and Lr26 and virulence (ITs 3 to 4) for lines with Lr2c, Lr3, Lr3ka, Lr10, Lr14a, Lr17, Lr18, Lr30, and LrB. Thatcher lines with LrB, Lr10, Lr14a, and Lr18 were added as the fourth set to the 12 original differential lines (1,2). This profile codes to race FBPT according to the North American system, and, based on these differentials, resembles a P. triticina isolate from Gwebi, Zimbabwe, in 2012 (Z. A. Pretorius, unpublished data). When additional single gene lines were tested with FBPT (race 3SA147 according to the ARC-Small Grain Institute rust notation procedure), lines with Lr2b, Lr15, Lr19, Lr20, Lr21, Lr25, Lr27+31, Lr28, Lr29, Lr32, Lr36, Lr38, Lr45, Lr47, Lr50, Lr51, and Lr52 were effective, whereas lines with Lr3bg, Lr23, Lr28, and Lr33 were ineffective. In adult plant tests in a greenhouse, Thatcher lines containing Lr12 (IT ;1c), Lr13 (IT ;1c), Lr22a (IT 1), Lr35 (IT ;1+), and Lr37 (IT ;1) were resistant, whereas Thatcher (Lr22b) was susceptible. Of 146 South African cultivars and lines infected as seedlings with 3SA147 (FBPT), 83% were resistant (IT ≤ 2) and 5% showed within-line variation. Entries showing compatible ITs with 3SA147 (FBPT) were also susceptible to either or both of 3SA133 (PDRS) and 3SA146 (MCDS). In addition, the new race was genotyped using 16 simple sequence repeat (SSR) primer-combinations (3). Three single pustule isolates of 3SA147 (FBPT) were identical and showed 82% and 76% similarity with the recently described races 3SA146 (MCDS) and 3SA145 (CCPS), respectively (4). Minimum spanning network analysis confirmed this close genetic relationship among the three races. However, since their virulence phenotypes differ, it is proposed that 3SA147 (FBPT) is not a stepwise mutation from either 3SA145 (CCPS) or 3SA146 (MCDS), but rather a foreign introduction into South Africa. As most current breeding lines and wheat cultivars are resistant, it is unlikely that race FBPT will threaten wheat production in South Africa, but its detection underlines the fact that new P. triticina variants have been occurring at regular intervals in the region. References: (1) J. A. Kolmer et al. Austr. J. Agric. Res. 58:631, 2007. (2) D. L. Long and J. A. Kolmer. Plant Dis. 79:525, 1989. (3) L. J. Szabo and J. A. Kolmer. Mol. Ecol. Notes 7:708, 2007. (4) T. Terefe et al. Plant Dis. 95:611, 2011.

scholarly journals First Report of a New Wheat Leaf Rust (Puccinia triticina) Race with Virulence for Lr12, 13, and 37 in South Africa

Plant Disease ◽  
2011 ◽  
Vol 95 (5) ◽  
pp. 611-611 ◽  
Author(s):  
T. Terefe ◽  
Z. A. Pretorius ◽  
C. M. Bender ◽  
B. Visser ◽  
L. Herselman ◽  
...  
Keyword(s):  
South Africa ◽  
Leaf Rust ◽  
South African ◽  
Adult Plant Resistance ◽  
Flag Leaf ◽  
Puccinia Triticina ◽  
Adult Plant ◽  
Western Cape ◽  
Wheat Leaf ◽  
New Race

A new race of Puccinia triticina was collected from common wheat (Triticum aestivum) in the Eastern and Western Cape provinces during the annual rust survey in 2009. Six single-pustule isolates from a field collection, which were shown to be a new race in preliminary analyses, were inoculated onto seedlings of 16 Thatcher (Tc) near-isogenic differential lines (1) and other tester lines with known Lr genes. Standard procedures for inoculation, incubation, and rust evaluation were followed (4) and all infection studies were repeated. The low infection type of Lr18 was confirmed at 18°C. All six isolates were avirulent (infection types [ITs] 0; to 2) to Lr1, 2a, 2c, 9, 11, 16, 18, and 24 and virulent (ITs 3 to 4) to Lr3, 3ka, 10, 14a, 17, 26, 30, B, and Tc (control). The new race, named 3SA145 according to the ARC-Small Grain Institute notation, corresponds to race CCPS in the North American system (1). On the basis of seedling ITs of the extended Lr gene set, 3SA145 was avirulent (ITs 0; to 22+) to Lr2b, 19, 21, 23, 25, 28, 29, 32, 36 (E84081), 38, 45, 47 (KS90H450), 50 (KS96WGRC36), 51 (R05), and 52 and virulent to Lr3bg, 15, 20 (Thew), 27+31 (Gatcher), and 33. Lines containing the adult plant resistance (APR) genes Lr12 (RL6011, IT 3++), Lr13 (CT263, IT 3), Lr22b (Tc, IT 4), and Lr37 (RL6081, IT 3) were susceptible in the adult stage to 3SA145, whereas lines with the APR genes Lr22a (RL6044, IT ;1), Lr34 (RL6058, IT Z1), and Lr35 (RL6082, IT ;1) were resistant in controlled infection studies in a greenhouse. A control, the common race (3SA133), was virulent only on Tc adult plants. In seedlings, 3SA133 was avirulent to Lr15, 17, 26, and 27+31, but unlike 3SA145, it was virulent to Lr1, 2c, 11, 18, 24, and 28. Races 3SA133 and 3SA145 did not differ in their virulence to the remaining seedling genes. Virulence to Lr37 has been reported in several countries, including Australia, Canada, Uruguay, and the United States (1,2). Prior to the detection of 3SA145, adult plants of RL6081 were resistant to all wheat leaf rust races in South Africa. In 2009, however, RL6081 showed severity levels of up to 30S at certain Western Cape trap plot sites. Of 124 South African bread wheat cultivars and advanced breeding lines tested at the seedling stage, 3SA145 was virulent to 48, whereas 3SA133 was virulent to 36 entries. A further six entries were heterogeneous in their reaction to 3SA145. In adult plant infection studies of 48 South African spring wheats in a greenhouse, 19 were susceptible (flag leaf IT ≥3) and 22 were resistant to 3SA145. Seven entries showed a Z3 flag leaf IT indicating adult plant resistance. According to a simple sequence repeat (SSR) study using 17 primer-pair combinations described by Szabo and Kolmer (3), 3SA145 showed 30% homology with the dominant South African races. Although virulence to Lr12 and Lr13 has been known in different leaf rust races in South Africa, to our knowledge, this is the first report of combined virulence to Lr12, 13, and 37. The SSR data and unique avirulence/virulence profile suggest that 3SA145 may be an exotic introduction to South Africa. References: (1) J. A. Kolmer et al. Plant Dis. 89:1201, 2005. (2) B. McCallum and P. Seto-Goh. Can. J. Plant Pathol. 31:80, 2009. (3) L. Szabo and J. Kolmer. Mol. Ecol. Notes 7:708, 2007. (4) T. Terefe et al. S. Afr. J. Plant Soil 26:51, 2009.

scholarly journals Resistance to rusts in Bangladeshi wheat (Triticum aestivum L.)

2011 ◽  
Vol 47 (Special Issue) ◽  
pp. S155-S159 ◽  
Author(s):  
P.K. Malaker ◽  
M.M.A. Reza
Keyword(s):  
Stem Rust ◽  
Rust Resistance ◽  
Yellow Rust ◽  
Puccinia Triticina ◽  
Triticum Aestivum L ◽  
Adult Plant ◽  
Wheat Varieties ◽  
Breeding Lines ◽  
Slow Rusting ◽  
Resistant Lines

Leaf rust caused by Puccinia triticina is the most important disease among the three rusts of wheat in Bangladesh. The disease occurs in all wheat growing areas of the country with varying degrees of severity. Stem rust caused by P. graminis f.sp. tritici was last observed during the mid 1980s, while yellow rust caused by P. striiformis f.sp. tritici occurs occasionally in the north-western region, where a relatively cooler climate prevails during the winter months. None of the rusts has yet reached an epidemic level, but damaging epidemics may occur in future, particularly if a virulent race develops or is introduced. The genes conferring rust resistance in the breeding lines and wheat varieties released in Bangladesh were investigated at CIMMYT-Mexico and DWR-India. The resistance genes Lr1, Lr3, Lr10, Lr13, Lr23 and Lr26, Sr2, Sr5, Sr7b, Sr8b, Sr9b, Sr11 and Sr31; and Yr2KS and Yr9 were found. An adult plant slow rusting resistance gene Lr34 was also identified in some of the breeding lines and varieties based on the presence of clear leaf tip necrosis under field conditions. Considering the possible risk of migration of the devastating Ug99 race of stem rust into the Indo-Pak subcontinent, the Bangladeshi wheat lines and cultivars are being regularly sent to KARI in Kenya for testing their resistance against this race. The resistant lines have been included in multi-location yield trials and multiplied for future use in order to mitigate the threat of Ug99. The resistant lines have also been included in crossing schemes to develop genetic diversity of rust resistance.

scholarly journals Lr19 Resistance in Wheat Becomes Susceptible to Puccinia triticina in India

Plant Disease ◽  
2005 ◽  
Vol 89 (12) ◽  
pp. 1360-1360 ◽  
Author(s):  
S. C. Bhardwaj ◽  
M. Prashar ◽  
S. Kumar ◽  
S. K. Jain ◽  
D. Datta
Keyword(s):  
Leaf Rust ◽  
Wheat Variety ◽  
Puccinia Triticina ◽  
Triticum Aestivum L ◽  
Wheat Breeding ◽  
Adult Plant ◽  
Distribution Data ◽  
Agropyron Elongatum ◽  
Peninsular India ◽  
Slow Rusting

Lr19, a resistance gene originally transferred from Agropyron elongatum to wheat (Triticum aestivum L.), has remained effective worldwide against leaf rust (Puccinia triticina Eriks.) except in Mexico (1). This report records a new pathotype of P. triticina virulent on Lr19 from India. From 2003 to 2004, 622 wheat leaf rust samples from 14 states were subjected to pathotype analysis. Samples were established on susceptible wheat cv. Agra Local, and pathotypes were identified on three sets of differentials following binomial nomenclature (3). Virulence on Lr19 (Agatha T4 line) was observed in approximately 2% of samples. These samples were picked from Lr19 (NIL), cvs. Ajit, Lal Bahadur, Local Red, Lok1, and Nirbhay from Karnataka and Gujarat states. All Lr19 virulent isolates were identical. The reference culture is being maintained on susceptible wheat cv. Agra Local and has also been put under long-term storage in a national repository at Flowerdale. From 2004 to 2005, this pathotype was detected in 6.3% of samples from central and peninsular India. There is no wheat variety with Lr19 under cultivation in India, however, it is being used in wheat breeding programs targeted at building resistance against leaf and stem rusts. NIL's Lr19/Sr25 (LC25) and Lr19/Sr25 (82.2711) were also susceptible to this isolate, whereas Lr19/Sr25 (spring accession) was resistant. The new isolate, designated as 253R31 (77-8), appears to be close to the pathotype 109R31 (4) with additional virulence for Lr19. The avirulence/virulence formula of pathotype 253R31 is Lr9, 23, 24, 25, 26, 27+31, 28, 29, 32, 36, 39, 41, 42, 43, 45/Lr1, 2a, 2b, 2c, 3, 10, 11, 12, 13, 14a, 14b, 14ab, 15, 16, 17, 18, 20, 21, 22a, 22b, 30, 33, 34, 35, 37, 38, 40, 44, 48, and 49. To our knowledge, this is the first report of virulence on Lr19 from two states of India. On international rust differentials, it is designated as TGTTQ (2), and is different from CBJ/QQ (1), the other isolate reported virulent on Lr19 from Mexico. The Mexican isolate is avirulent on Lr1, 2a, 2b, 2c, 3ka, 16, 21, and 30 to which the Indian isolate is virulent. However, both isolates are avirulent on Lr9, 24, 26, 36, and Lr42. Among the wheat cultivars identified during the last 6 years, HD2824, HD2833, HD2864, HI1500, HS375, HUW 510, HW 2044, HW 5001, Lok 45, MACS 6145, MP4010, NW 2036, PBW 443, PBW 498, PBW 502, PBW 524, Raj 4037, UP 2565, VL 804, VL 829, and VL 832 and lines of wheat possessing Lr9, Lr23, Lr24, and Lr26 showed resistance to this pathotype. PBW 343, which occupies more than 5 million ha in India, is also resistant to this pathotype along with PBW 373. An integrated strategy using a combination of diverse resistance genes, deployment of cultivars by using pathotype distribution data, slow rusting, and adult plant resistance is in place to curtail selection of new pathotypes and prevent rust epiphytotics. References: (1) J. Huerta-Espino and R. P. Singh. Plant Dis. 78:640,1994. (2) D. V. Mc Vey et al. Plant Dis. 88:271, 2004. (3) S. Nagarajan et al. Curr. Sci. 52:413, 1983. (4) S. K. Nayar et al. Curr. Sci. 44:742, 1975.

Physiologic Specialization and Genetic Differentiation of Puccinia triticina Causing Leaf Rust of Wheat in the Indian Subcontinent during 2016-2019

Plant Disease ◽  
2021 ◽  
Author(s):  
Subhash Chander Bhardwaj ◽  
Subodh Kumar ◽  
Om Prakash Gangwar ◽  
Pramod Prasad ◽  
Prem Lal Kashyap ◽  
...  
Keyword(s):  
Leaf Rust ◽  
Indian Subcontinent ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
International Communication ◽  
Field Resistance ◽  
Adult Plant ◽  
Wheat Varieties ◽  
The North ◽  
High Degree

Wheat is the second most cultivated cereal in the world and is equally important in India. Leaf (brown) rust, caused by Puccinia triticina, was most prevalent among the three rusts in all the wheat-growing areas of India, Bhutan, and Nepal during 2016 to 2019. Leaf rust samples from wheat crops in these countries were pathotyped using the wheat differential genotypes and binomial Indian system of nomenclature. To facilitate international communication, each pathotype identified was also tested on the North American differentials. A total of 33 pathotypes were identified from 1,086 samples, including 3 new pathotypes, 61R47 (162-5 = KHTDM) and 93R49 (49 = NHKTN) from India and 93R57 (20-1 = NHKTL) from Nepal. Two pathotypes, 121R60-1 (77-9/52 = MHTKL) and 121R63-1 (77-5 = THTTM), accounted for 79.46% of the population. Virulence on Lr19 was identified in 0.27% of the samples and from Nepal only. The proportion of pathotype 121R60-1 (77-9 = MHTKL) increased during these years to 57.55%. Virulence was not observed to Lr9, Lr24, Lr25, Lr28, Lr32, Lr39, Lr45, and Lr47 in the population of the Indian subcontinent. Eighteen polymorphic simple sequence repeat (SSR) primer pairs tested on the isolates amplified 48 alleles with an average of 2.66 alleles per primer pair. Based on SSR genotyping, these pathotypes could be grouped into two clades with further two subclades each. Many of the Lr genes present in Indian wheat germplasm (Lr1, Lr3a, Lr10, Lr11, Lr14a, Lr15, Lr16, Lr17, Lr20, Lr23, and Lr26) were ineffective to a majority of the pathotypes. Most of these varieties possessed a high degree of leaf rust resistance. The field resistance of wheat varieties could be attributed to the interaction of genes, unknown resistance, or adult plant resistance.

scholarly journals Accomplishments in wheat rust research in South Africa

2020 ◽  
Vol 116 (11/12) ◽  
Author(s):  
Zacharias A. Pretorius van der Walt ◽  
Renée Prins ◽  
Elsabet Wessels ◽  
Cornel M. Bender ◽  
Botma Visser ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
New Technologies ◽  
Puccinia Triticina ◽  
Sources Of Resistance ◽  
Breeding Lines ◽  
Rust Diseases ◽  
African Populations ◽  
Pathogen Populations ◽  
Wheat Rust

Rust diseases, although seasonal, have been severe constraints in wheat production in South Africa for almost 300 years. Rust research gained momentum with the institution of annual surveys in the 1980s, followed by race identification, an understanding of rust epidemiology, and eventually a focused collaboration amongst pathologists, breeders and geneticists. Diversity in South African populations of Puccinia triticina, P. graminis f. sp. tritici and P. striiformis f. sp. tritici has been described and isolates are available to accurately phenotype wheat germplasm and study pathogen populations at national, regional and global levels. Sources of resistance have been, and still are, methodically analysed and molecular marker systems were developed to incorporate, stack and verify complex resistance gene combinations in breeding lines and cultivars. Vigilance, capacity, new technologies, collaboration and sustained funding are critical for maintaining and improving the current research impetus for future management of these important diseases.

scholarly journals Two new species of Erica (Ericaceae) from the Langeberg, Western Cape, South Africa

Bothalia ◽  
2006 ◽  
Vol 36 (1) ◽  
pp. 33-37 ◽  
Author(s):  
R. C. Turner ◽  
E. G. H. Oliver
Keyword(s):  
South Africa ◽  
New Species ◽  
Nature Reserve ◽  
Type Locality ◽  
Western Cape ◽  
Mountain Slope ◽  
The North ◽  
Two New Species

Two new species of the genus Erica L. from the north-facing slopes of the Langeberg are described— E turneri,  known only from the type locality on Zuurbraak Mountain and E. euryphylla,  occurring on the same mountain slope, as well as on the middle north-facing slopes   of Hermitage Peak near Misty Point in the Marloth Nature Reserve above Swellendam.

scholarly journals History of ‘swine fever’ in Southern Africa

2013 ◽  
Vol 84 (1) ◽  
Author(s):  
Mary-Louise Penrith
Keyword(s):  
South Africa ◽  
Southern Africa ◽  
African Swine Fever ◽  
Classical Swine Fever ◽  
Western Cape ◽  
Eastern Cape ◽  
African Region ◽  
African Countries ◽  
The North ◽  
History Of

The histories of the two swine fevers in southern Africa differ widely. Classical swine fever (hog cholera) has been known in the northern hemisphere since 1830 and it is probable that early cases of ‘swine fever’ in European settlers’ pigs in southern Africa were accepted to be that disease. It was only in 1921 that the first description of African swine fever as an entity different from classical swine fever was published after the disease had been studied in settlers’ pigs in Kenya. Shortly after that, reports of African swine fever in settlers’ pigs emerged from South Africa and Angola. In South Africa, the report related to pigs in the north-eastern part of the country. Previously (in 1905 or earlier) a disease assumed to be classical swine fever caused high mortality among pigs in the Western Cape and was only eradicated in 1918. African swine fever was found over the following years to be endemic in most southern African countries. Classical swine fever, however, apart from an introduction with subsequent endemic establishment in Madagascar and a number of introductions into Mauritius, the last one in 2000, had apparently remained absent from the region until it was diagnosed in the Western and subsequently the Eastern Cape of South Africa in 2005. It was eradicated by 2007. The history of these diseases in the southern African region demonstrates their importance and their potential for spread over long distances, emphasising the need for improved management of both diseases wherever they occur.

scholarly journals Adult Plant Leaf Rust Resistance Derived from Toropi Wheat is Conditioned by Lr78 and Three Minor QTL

2018 ◽  
Vol 108 (2) ◽  
pp. 246-253 ◽  
Author(s):  
J. A. Kolmer ◽  
A. Bernardo ◽  
G. Bai ◽  
M. J. Hayden ◽  
S. Chao
Keyword(s):  
Leaf Rust ◽  
Resistance Genes ◽  
Rust Resistance ◽  
Recombinant Inbred Lines ◽  
Single Gene ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
Adult Plant ◽  
Field Plot ◽  
Plant Leaf

Leaf rust caused by Puccinia triticina is an important disease of wheat in many regions worldwide. Durable or long-lasting leaf rust resistance has been difficult to achieve because populations of P. triticina are highly variable for virulence to race-specific resistance genes, and respond to selection by resistance genes in released wheat cultivars. The wheat cultivar Toropi, developed and grown in Brazil, was noted to have long-lasting leaf rust resistance that was effective only in adult plants. The objectives of this study were to determine the chromosome location of the leaf rust resistance genes derived from Toropi in two populations of recombinant inbred lines in a partial Thatcher wheat background. In the first population, a single gene with major effects on chromosome 5DS that mapped 2.2 centimorgans distal to IWA6289, strongly reduced leaf rust severity in all 3 years of field plot tests. This gene for adult plant leaf rust resistance was designated as Lr78. In the second population, quantitative trait loci (QTL) with small effects on chromosomes 1BL, 3BS, and 4BS were found. These QTL expressed inconsistently over 4 years of field plot tests. The adult plant leaf rust resistance derived from Toropi involved a complex combination of QTL with large and small effects.

EFFECTIVENESS OF KNOWN WHEAT RESISTANCE GENES TO PUCCINIA TRITICINA IN THE ADULT PLANT PHASE IN SOUTHERN RUSSIA

2020 ◽  
Author(s):  
V.D. Agapova ◽  
◽  
O.F. Vaganova ◽  
M.S. Gvozdeva ◽  
G.V. Volkova ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Resistance Genes ◽  
Plant Protection ◽  
Puccinia Triticina ◽  
Adult Plant ◽  
North Caucasus ◽  
The South ◽  
Caucasus Region ◽  
The North ◽  
Russian Research Institute

Winter wheat is one of the leading agricultural crops in Russia. The most common and epiphytotic pathogen is leaf rust (Puccinia triticina). The aim of the work was to evaluate the effectiveness of known wheat resistance genes to brown rust in the phase of adult plants in the South of Russia. For the study, route surveys were conducted in the conditions of the North Caucasus region, and herbarium material was collected to create an infectious background on the field site of the FSBI “All-Russian Research Institute of Biological Plant Protection”. As a result of the evaluation of 49 isogenic lines of winter wheat, the Lr9, Lr42, Lr43+24 and Lr50 genes with absolute resistance to P. triticina were identified in the South of Russia in 2019. Study of lines with known resistance genes on an infectious background in the field gives an idea of the change in the effectiveness of P. triticina Lr genes.

Sign in / Sign up

Export Citation Format

Share Document