egypt atef shahin-slow-rusting_resistance_in_20_egyptian_wheat_cultivars
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- 1.Atef A. Shahin, Ph.D Wheat Disease Research DepartmentWheat Disease Research Department Plant Pathology Research InstitutePlant Pathology Research Institute ARC, EgyptARC, Egypt Email: email@example.comEmail: firstname.lastname@example.org Rusts never sleep "Rusts never sleep "
2. - In 2010 African countries spent more than 12.5 billion US$ to import of 32 million tons of wheat. - Demand for wheat in Africa is growing faster than for any other food crop. This will be a major challenge particularly in cities, where urban population growth is forecasted to increase by 300% by 2050. - Major biotic and abiotic constraints of wheat production in Africa related to climate change. 3. reminds us of the words of the late Nobel Prize winner, Norman Borlaug that "rusts never sleep""rusts never sleep" 4. Country /Year Crop losses Millions $ USA 2000-07 2010 6.5 million tones 2.2 millions tones $US 30 Washington State Australia 2003-2006 AU$ 30-90 China 1950 64, 90,02 14.4 million tones More than 20 million Turkey 1992 1996 2000 2009-10 26.5% (Gereck > 1 m ha) 1.2 million tones 3% Gerek 79 568 53 10 Iran 1992-94 2007 and 09 2010 2.5 milliom tones 2 million ha 650.000 ha spray 258 ? ? Syria 2010 Cham 8 (80% yield loss) 80% of Area Ethiopia 2010 $US 3.2 in fungicide application in Ethiopia Impact of Stripe Rust Epidemics Worldwide During the last decades, several yellow rust epidemics in most of the wheat-growing areas 5. Wheat rusts and loose smut are the major diseases of wheat in Egypt. Also, powdery mildew became more dangerous at recent years. So wheat diseases section aims to control these diseases throughout identification of virulent races, evaluation of breeding materials for resistance varieties and fungicides efficacies. 1. 1947 (Giza 144) 2. 1986 (Sakha 8) 3. 1995 (Gemmeiza-1 and Giza163). 4. 1997 (Sakha 69). Several epidemics of wheat yellow rust have been reported in Egypt causing significant crop losses 6. Stripe rust caused by Puccinia striiformis f. sp. tritici is widely distributed and dangerous. It affects wheat crop through damaging its respiratory system, kills foliar parts, makes growth of plant stunted, most importantly reduces grain yield by shriveling grain, reducing weight and affecting its quality. Stripe rustStripe rust Also known as Yellow rust Puccinia striiformis Westend. [teleomorph] Uredo glumarum J.C. Schmidt [anamorph] 7. High yielding new cultivars 1. Miser1 2. Miser 2 3. Gemmeiza-10 4. Sids-12 Wheat is one of the most important food crops allover the world and essential in Egypt. The national production of such crop reached to 8 million tons in 2010 obtained from an acreage of 3 million feddans the annual consumption reached to 2/3, consequently the balance amount is imported from high wheat production countries. To fill the gap between consumption and production through both vertical and horizontal extension via increasing the productivity of acreage unit through high yielding varieties and controlling diseases. 8. The main objectives of the present investigation were to determine the components of slow- rusting in 20 Egyptian wheat cultivars and Little Club as a standard susceptible one against virulent isolates of stripe rust under greenhouse and field conditions to be exploited in the promising lines in the breeding program of wheat for rust resistance. The ObjectivesThe Objectives 9. Studied area:Studied area: The studied area is located in North Delta region, Kafrelsheikh (31 08 North and 30 56 East). Climatic condition of the studied area is typically arid Mediterranean climate. Regular field surveys were annually conducted across wheat growing area in Egypt, especially in area considered source the inoculum i.e. Northern governorate of Egypt i.e. Kafrelsheikh. Field surveys and isolate collections 10. One infected fields in Kafrelsheikh governorate , registration data and collection of samples infected. Annual survey (Commercial fields and Egyptian Wheat Trap Rust Nursery). Data of collection location, cultivar, severity, collector and any other relevant information were recorded for each sample. 11. Twenty cultivars of wheat were used to study both seedling and adult stage to stripe rust were compared with the susceptible hosts Plants were grown in 10-cm diameter pots Seedling evaluation wheat accessions against yellow rust Inoculated pots were incubated at 10 c in darkness and 100% relative humidity for 24h. Then transferred to permanent cabinets at diurnal system. Seedlings of 10 days old, inoculation was conducted by spraying of them with mixture of spores and talcum powder (in 1:4 proportions). 12. seedling infection type in response to wheat stripe rust . This greenhouse test helps to detect seedling resistance. This greenhouse test helps to detect seedling resistance. If a wheat line shows a susceptible response it may either be susceptible to the disease or carry adult plant resistance (APR). APR often indicates the presence of slow rusting genes that can be combined through breeding to produce materials with durable rust resistance. Infection Type (IT) was recorded based on the 0-4 scale with ITs 3 and 4combined as 3 (the most susceptible reaction) in field data. Generally IT 0-2 areconsidered resistant, 2-3 intermediate, and 3-4 susceptible. Heterogenous reactions of an entry were indicated by two or more ITs separated by "," for most plants with the first IT and few plants with the second IT or connected with "-" for entries containing plants with continuous ITs. Entries with a high IT in the first note, but a low IT in the second note may indicate that they have high-temperature, adult-plant (HTAP) resistance. 13. Resistance reaction was recorded based on McIntosh et al. (1995) using the scale 0-4, 0 = no visible uredia, 1 = small uredia with necrosis, 2 = small to medium sized uredia with green islands and surrounded by necrosis or chlorosis, 3 = medium sized uredia with or without chlorosis and 4 = large uredia without chlorosis). Infection Types (ITs) of 3+ or higher were regarded as susceptible, whereas ITs of 3 or lower were regarded as resistant. Stripe rust (L to R): IT 0, ; , ;N , 1+ , 2C , 3 , 4 14. Artificial inoculation was carried out with a mixture of races by spraying all tested entries and spreader rows with a mixture of spores and talcum powder (in 1:20 proportions), two times after the sun set. Percent severity was recorded four times, starting when Morocco reached 30% severity according to the modified Cobb scale (Peterson et al., 1948) and reaction based on (Roelfs et al., 1992). 15. Artificial inoculation was carried out with Sakha races by spraying all test entries and spreader rows with mixture of spores and talcum powder (in 1:20 proportions), two times after the sun set. Percent severity was recorded four times, starting when Morocco reached 30% severity according to the modified Cobb scale (Peterson, 1948) and reaction based on Roelfs et al. (1992). Coefficient of Infection (CI) which are calculated by combination of Disease Severity (DS) and Infection Type (IT), was used for estimating of Area Under Disease Progress Curve (AUDPC) after converting by formula; . Constant values for infection types were used based on (immune = 0, R = 0.2, MR = 0.4, M = 0.6, MS = 0.8, S = 1; Stubbs et al., 1986). Estimation of AUDPC and rAUDPC was performed as follows ( Milus and Line, 1986): where, X1, X2 and X3, X4 are the rust intensities recorded on the first, second, third and fourth recording dates. N1 is interval day between X1, X2 and N2 is interval day between X2, X3 and N3 is interval day between X3 and X4: 16. Coefficient of Infection (CI) which is calculated by combinations of Disease Severity (DS) and Infection Type (IT), was used for estimating of Area Under Disease Progress Curve (AUDPC). Constant values for infection types were used based on (immune = 0, R = 0.2, MR = 0.4, M = 0.6, MS = 0.8, S = 1; (Stubbs et al., 1986). Estimation of AUDPC and rAUDPC was performed according to the following equation adopted by (Milus and Line, 1986). 17. Adult plant infection type, seedling reaction and mean comparison for coefficient of infection, AUDPC and rAUDPC in Egyptian wheat cultivars to yellow rust Cultivars Mean comparison based on Duncan multiple testing* Seedling reaction Adult plant reaction Mean of coefficient of infection Mean of AUDPC Mean of rAUDPC Misr1 I-R 1 30 4.46 2 Misr2 R-MR 1.4 42 6.25 3 Giza 167 MS-S 45 460 68.54 4 Giza168 MR-MS 10 72 10.71 3 Sakha61 R 1 30 4.46 3 Sakha93 MS 32 168 25 3 Sakha94 MR-MS 7 78 7.14 3 Gemmeiza5 MS-S 41.5 360 53.57 3 Gemmeiza7 MR-MS 7 96 14.28 3 Gemmeiza10 I-R 1 36 5.35 1+ Gemmeiza11 I-R 1 32 4.76 1+ Sids1 MS-S 23 360 53.57 4 Sids12 R 1.9 52 7.73 3+ Sids13 I-R 1 34 5.05 1+ Shandaweel1 MR 6.4 52 7.73 2+ Beni Sweif1 MS-S 22 228 33.92 4 Beni Sweif4 I-R 1 42 6.25 3 Beni Sweif5 I-R 1 36 5.35 3 Beni Sweif6 MR 6 64 9.25 4 Sohag3 I-R 1 36 5.35 2+ Morocco S 94.55 672 100 4 18. Monthly precipitation, mean temperature and moisture during the growing seasons 2010/2011 and 2011/2012 at Sakha station, Kafrelsheikh. Months Temperature C Precipitation (mm) RH% 2010/2011 2011/2012 2010/2011 2011/2012 2010/2011 2011/2012 November 18.91 17.06 - - 73.63 70.43 December 15.56 13.31 14.60 20.6 72.58 73.56 January 13.50 09.20 20.73 32.48 71.38 68.88 February 15.40 10.47 12.7 32.74 70.50 68.83 March 14.70 13.26 15.35 42.75 69.31 68.47 April 18.21 18.04 11.1 - 66.14 63.53 May 21.60 21.67 - - 58.11 62.87 19. Cultivars Reaction 2010/2011 2011/2012 Misr1 R R Misr2 R 5MR Giza 167 50MS 50S Giza168 10MR 20MS Sakha93 40MS 40MS Sakha94 10MR-MS 10MS Gemmeiza5 40MS 50S Gemmeiza7 10MR-MS 10MS Sids-1 20MS 30S Sids12 R R Beni Sweif1 30MS 20S Beni Sweif4 I-R I-R Morocco 80S 90S Adult plant infection type 20. Thousand kernel weight (g.), and their reduction % of different wheat genotypes in the presence and absence of stripe rust during 2010/2011 and 2011/2012 at Sakha station, Kafrelsheikh. Cultivars 100