Posts Tagged ‘Yellow rust’

Temperature adaptation in Australasian populations of Puccinia striiformis f. sp. tritici.

Posted by Carelia Juarez on , in Journal Articles

Published in Plant Pathology 63 (3572-580, 2014

Loladze, A.; Druml, T.; Wellings, C.R.

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the major fungal pathogens of wheat. A new pathotype was introduced to Australia in 2002 and several derivative pathotypes were detected in subsequent seasons. It has been suggested that the severity of stripe rust outbreaks in Australia since 2002 could be as a result of traits other than virulence in the pathogen population. This study was conducted to investigate the hypothesis that the stripe rust pathogen population dominant in Australia since 2002 was better adapted to warm temperature conditions compared to previous pathogen populations. Sixteen pathotypes were selected to examine the influence of two contrasting temperature regimes during the 24 h incubation (10°C and 15°C) and the subsequent post-inoculation (17°C and 23°C) periods on latent period and infection efficiency on four susceptible wheat cultivars. In addition, the effect of two contrasting incubation temperatures on urediniospore germination was examined. The results indicated that pathotypes of P. striiformis f. sp. tritici detected after 2002 did not show evidence of adaptation to high temperatures, which suggests that other factors contributed to the observed increased aggressiveness.

QTL characterization of resistance to leaf rust and stripe rust in the spring wheat line Francolin#1

Posted by Carelia Juarez on , in Journal Articles

Published in Molecular Breeding, 2014

Caixia Lan;Rosewarne, G.M.; Singh, R.P.; Herrera-Foessel, S.A.; Huerta-Espino, J.; Basnet, B.R.; Yelun Zhang; Ennian Yang.

Growing resistant wheat varieties is a key method of controlling two important wheat diseases, leaf rust and stripe rust. We analyzed quantitative trait loci (QTL) to investigate adult plant resistance (APR) to these rusts, using 141 F5 RILs derived from the cross ‘Avocet-YrA/Francolin#1’. Phenotyping of leaf rust resistance was conducted during two seasons at Ciudad Obregon, Mexico, whereas stripe rust was evaluated for two seasons in Toluca, Mexico, and one season in Chengdu, China. The genetic map was constructed with 581 markers, including diversity arrays technology and simple sequence repeat. Significant loci for reducing leaf rust severity were designated QLr.cim1BLQLr.cim3BS.1QLr.cim3DC, and QLr.cim7DS. The six QTL that reduced stripe rust severity were designated QYr.cim1BLQYr.cim2BSQYr.cim2DSQYr.cim3BS.2QYr.cim5AL, andQYr.cim6AL. All loci were conferred by Francolin#1, with the exception of QYr.cim2DSQYr.cim5AL, and QYr.cim6AL, which were derived from Avocet-YrA. Closely linked markers indicated that the 1BL locus was the pleiotropic APR gene Lr46/Yr29QYr.cim2BS was a seedling resistance gene designated as YrF that conferred intermediate seedling reactions and moderate resistance at the adult plant stage in both Mexican and Chinese environments. Significant additive interactions were detected between the six QTL for stripe rust, but not between the four QTL for leaf rust. Furthermore, we detected two new APR loci for leaf rust in common wheat: QLr.cim3BS.1 andQLr.cim7DS.

Reaction of some of Afghanistan’s wheat varieties to yellow rust under natural conditions

Posted by Carelia Juarez on , in Journal Articles

Published in African Journal of Agricultural Research 8 (14) : 1255-1257, 2013

Ahmadzada, Z.;Obaidi, M.Q.; Ghanizada, A.G.; Mashook, M.; Azmatyar, M.H.; Jan, A.; Qayum, A.; Mohmand, E.; Sharma, R.K.

Afghanistan grows wheat at about 2.5 million ha, about 45% of which is irrigated. The country is not wheat sufficient and has been importing to meet domestic needs. Yellow rust is the most important disease of wheat in Afghanistan. Country has been able to manage wheat rusts mainly by having a survey surveillance system in place and by releasing resistant varieties. A total of 30 wheat varieties released during last two decades were screened for rust resistance under natural epiphytotic conditions. The rust reaction observed on two dates at one week interval revealed very fast increase in yellow rust infection. A large number of varieties e.g., Gul-96, Pamir-94, Ghori-96, HD2285 etc., were found to have very high yellow rust scores warranting their removal from seed chain.

Characterization of Yr54 and other genes associated with adult plant resistance to yellow rust and leaf rust in common wheat Quaiu 3

Posted by Carelia Juarez on , in Journal Articles

Published in Molecular Breeding, 2013

Basnet, B.R.; Singh, R.P.; Ibrahim, A.M.H.; Herrera-Foessel, S.A.; Huerta-Espino, J.; Lan, C.; Rudd, J.C.

Leaf rust (LR) and yellow rust (YR), caused by Puccinia triticina and Puccinia striiformis f. sp. tritici, respectively, are important diseases of wheat. Quaiu 3, a common wheat line developed at the International Maize and Wheat Improvement Center (CIMMYT), is immune to YR in Mexico despite seedling susceptibility to predominant races. Quaiu 3 also shows immunity to LR in field trials and is known to possess the race-specific gene Lr42. A mapping population of 182 recombinant inbred lines (RILs) was developed by crossing Quaiu 3 with susceptible Avocet-YrA and phenotyped with LR and YR in field trials for 2 years in Mexico. Quantitative trait loci (QTL) associated with YR and LR resistance in the RILs were identified using Diversity Arrays Technology and simple sequence repeat markers. A large-effect QTL on the long arm of chromosome 2D explained 49–54 % of the phenotypic variation in Quaiu 3 and was designated as Yr54. Two additional loci on 1BL and 3BS explained 8–17 % of the phenotypic variation for YR and coincided with previously characterized adult plant resistance (APR) genes Lr46/Yr29 and Sr2/Yr30, respectively. QTL on 1DS and 1BL corresponding to Lr42 and Lr46/Yr29, respectively, contributed 60–71 % of the variation for LR resistance. A locus on 3D associated with APR to both diseases explained up to 7 % of the phenotypic variance. Additional Avocet-YrA-derived minor QTL were also detected for YR on chromosomes 1A, 3D, 4A, and 6A. Yr54 is a newly characterized APR gene which can be combined with other genes by using closely linked molecular markers.

Genetic analysis of adult plant resistance to yellow rust and leaf rust in common spring wheat Quaiu 3

Posted by Carelia Juarez on , in Journal Articles

Published in Plant Disease, 2013

Bhoja Raj Basnet, Ravi P. Singh, Sybil A. Herrera-Foessel, Amir M.H. Ibrahim, Julio Huerta-Espino, Violeta Calvo-Salazar and Jackie Rudd

Identifying and utilizing rust resistance genes in wheat has been hampered by the continuous and rapid emergence of new pathogen races. A major focus of many wheat breeding programs is achieving durable adult plant resistance (APR) to yellow (stripe) rust (YR) and leaf (brown) rust (LR), caused by Puccinia striiformis and P. triticina, respectively. This study aimed to determine the genetic basis of resistance to YR and LR in the common spring wheat Quaiu 3. To that end, we evaluated 198 F5 recombinant inbred lines (RILs), derived from a cross of susceptible variety Avocet-YrA with Quaiu 3, for APR to LR and YR in artificially inoculated field trials conducted in Mexico during the 2009 and 2010 growing seasons. High narrow-sense heritability (h2) estimates, ranging between 0.91 and 0.95, were obtained for both LR and YR disease severities for both years. The quantitative and qualitative approaches used to estimate gene numbers showed that, in addition to known resistance genes, there are at least two to three APR genes associated with LR and YR resistance in the RIL population. The moderately effective race-specific resistance gene Lr42 and the pleiotropic slow rusting APR gene Lr46/Yr29 were found to interact with additional unidentified APR genes. The unidentified APR genes should be of particular interest for further characterization through molecular mapping, and for utilization by wheat breeding programs. Key words: Durable resistance, slow rusting, APR, Yellow rust, Leaf rust

 

QTL Mapping for Adult-Plant Resistance to Stripe Rust in a Common Wheat RIL Population Derived from Chuanmai 32/Chuanyu 12

Posted by Carelia Juarez on , in Journal Articles

Published in Journal of Integrative Agriculture 11 (11) : 1775-1782, 2012

Wu Ling, Xia Xian-Chun, Zheng You-liang, Zhang Zheng-yu, Zhu Hua-zhong, Liu Yong-jian, Yang En-nian, Li Shi-zhao and He Zhonghu

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a devastating wheat disease worldwide. The Chinese wheat cultivar Chuanmai 32 has shown stable resistance to stripe rust for 10 yr in Sichuan Province, a hotspot for stripe rust epidemics. The objective of the present study was to map quantitative trait loci (QTL) for adult-plant resistance (APR) to stripe rust in a population of 140 recombinant inbred lines (RILs) derived from Chuanmai 32/Chuanyu 12. Field trials were conducted in Chengdu and Yaan, Sichuan, from 2005 to 2008, providing stripe rust reaction data for 6 environments. 797 simple sequence repeat (SSR) markers were screened for association with stripe rust reaction, initially through bulked segregant analysis (BSA). Based on the mean disease values averaged across environments, the broad-sense heritability of maximum disease severity (MDS) was 0.75. Two QTLs for stripe rust resistance were detected by composite interval mapping (CIM). They were designated QYr.caas-3BL and QYr.caas-3BS and explained from 6.6 to 20.1%, respectively, of the phenotypic variance across environments. QYr.caas-3BL came from Chuanmai 32; QYr.caas-3BS with lower effect was from the susceptible parent Chuanyu 12. Both QTLs appear to be new.

QTL mapping of adult-plant resistance to stripe rust in Chinese wheat cultivar Chuanyu 16

Posted by Carelia Juarez on , in Journal Articles

Published in Journal of Agricultural Science 4 (3): 57-70, 2012

Ling Wu, Youliang Zheng, Xianchun Xia, Yunliang Peng, Huazhong Zhu, Yongjian Liu, Yu Wu, Shizhao Li, Zhonghu He

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a serious wheat fungal disease, causing significant annual yield losses worldwide. The Chinese wheat cultivar Chuanyu 16 has shown good adult-plant resistance (APR) to stripe rust in Sichuan province, a hotspot for stripe rust epidemics. Chuanyu 16 was crossed with Chuanyu 12 and Chuanmai 32. Two populations, each with 140 recombinant inbred lines (RILs), were developed by single-seed descent, and used for quantitative trait locus (QTL) mapping. Field trials were conducted in Chengdu and Yaan from 2005 to 2008, providing stripe rust reaction data for six environments. Seven hundred and thirty one simple sequence repeat (SSR) markers were screened for association with stripe rust reaction, initially through bulked segregant analysis (BSA). Three QTLs for stripe rust resistance derived from Chuanyu 16 were detected in the first cross. They were detected by inclusive composite interval mapping (ICIM) and designated QYr.caas-1BL.1, QYr.caas-1BL.2 and QYr.caas-2AS. They explained 6.0 – 12.8%, 4.5 – 5.8% and 14.9 – 43.0%, respectively, of the phenotypic variance across environments. One digenic epistatic QTL between QYr.caas-1BL.2 and QYr.caas-2AS explained 4.3 – 10.4% of the phenotypic variance. QYr.caas-2AS was also detected in Chuanmai 32/Chuanyu 16, explaining 27.9 – 57.2% of the phenotypic variance across six environments. This QTL showed a major effect against stripe rust in Chuanyu 16, and was located in a similar position to Yr17. Specific markers indicated the presence of a segment from chromosome 2N of Triticum ventricosum that carries Yr17. Despite the lack of evidence for Yr17 in Chuanyu 16 based on pedigree, and inconsistencies in stripe rust response relative to a near-isogenic reference stock with the gene, we concluded that QYr.caas-2AS is Yr17. QYr.caas-1BL.1 and QYr.caas-1BL.2 showed minor effects for APR against stripe rust. QYr.caas-1BL.1 is probably a new gene for APR to stripe rust.

Improved winter wheat genotypes for Central and West Asia

Posted by Carelia Juarez on , in Journal Articles

Published in Euphytica, 2012

R. C. Sharma, S. Rajaram, S. Alikulov , Z. Ziyaev, S. Hazratkulova , M. Khodarahami , S. M. Nazeri, S. Belen, Z. Khalikulov, M. Mosaad, Y. Kaya, M. Keser, Z. Eshonova,  A. Kokhmetova, M. G. Ahmedov, M. R. Jalal Kamali  and A. I. Morgounov

High grain yield and resistance to stripe (yellow) rust are the most important traits for successful adoption of winter wheat varieties in Central and West Asia. This study was conducted to determine the stripe rust response and agronomic performance of a set of breeding lines recently developed by the International Winter Wheat Improvement Program (IWWIP). Replicated field studies were conducted in 2010 and 2011 using 38 experimental lines, one regional check (Konya) and one local check. Stripe rust scores were recorded at Karshi, Uzbekistan, and Karaj and Mashhad, Iran, in 2010. Grain yield was recorded at two sites each in Uzbekistan (Karshi and Kibray) and Iran (Karaj and Mashhad) and one site in Turkey (Eskisehir). The test lines showed variation for stripe rust severity, grain yield, 1,000-kernel weight, days to heading and plant height. Several stripe rust resistant genotypes were either higher yielding or equal to the local checks at different sites. Based on stripe rust resistance and yield performance in 2010, a set of 16 genotypes was selected and evaluated in 2011. All 16 were resistant at Almaty, Kazakhstan, and Dushanbe, Tajikistan, in 2011, whereas 9 of the 16 were resistant at Terter, Azerbaijan. The genotypes ‘TCI-02-138, ‘Solh’, ‘CMSS97M00541S’, ‘TCI -2-88(A)’ and ‘TCI-02-88(C)’ were consistently resistant to stripe across all sites in both years. Several lines showed high grain yields and superior agronomic performance across four sites in Uzbekistan and one site in Tajikistan. One genotype has been released in Uzbekistan and another in Tajikistan.

 

Improving wheat stripe rust resistance in Central Asia and the Caucasus

Posted by on , in Journal Articles

Published in Euphytica 179 (1); 197-207, 2011

Improving wheat stripe rust resistance in Central Asia and the Caucasus

Z. M. Ziyaev, R. C. Sharma, K. Nazari, A. I. Morgounov, A. A. Amanov, Z. F. Ziyadullaev, Z. I. Khalikulov and S. M. Alikulov

Wheat is the most important cereal in Central Asia (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) and the Caucasus (Armenia, Azerbaijan and Georgia). Stripe rust, caused by Puccinia striiformis f. sp. tritici is considered the most important disease of wheat in Central Asia and the Caucasus (CAC). Although stripe rust has been present in the region for a long time, it has become a serious constraint to wheat production in the past 10 years. This is reflected by the occurrence of five epidemics of stripe rust in the CAC region since 1999, the most recent in 2010. Several wheat varieties occupying substantial areas are either susceptible to stripe rust or possess a low level of resistance. Information on the stripe rust pathogen in terms of prevalent races and epidemiology is not readily available. Furthermore, there is an insufficient understanding of effective stripe rust resistance genes in the region, and little is known about the resistance genes present in the commercial varieties and advanced breeding lines. The deployment of resistant varieties is further complicated by putative changes in virulence in the pathogen population in different parts of the CAC. Twenty four out of 49 improved wheat lines received through international nurseries or other exchange programs showed high levels of resistance to stripe rust to local pathogen populations in 2009. Fifteen of the 24 stripe rust resistant lines also possessed resistance to powdery mildew. It is anticipated that this germplasm will play an important role in developing stripe rust resistant wheat varieties either through direct adoption or using them as parents in breeding programs.

http://www.springerlink.com/content/3858251175855787/