All BGRI Abstracts

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New QTL for leaf rust and stripe rust resistance in four bread wheat and two durum wheat mapping populations

BGRI 2018 Poster Abstract
Caixia Lan CIMMYT
Ravi,Singh, Julio, Huerta-Espino, Mandeep, Randhawa, , , , , , , , , , , , , , , , , , , , , , , ,

Wheat leaf rust (LR) and stripe rust (YR), caused by the air-borne fungi Puccinia triticina (Pt) and Puccinia striiformis f. sp. tritici (Pst), respectively, are considered the primary biotic threats to bread wheat and durum wheat production globally. Growing resistant wheat varieties is a key method of minimizing the extent of yield losses caused by these diseases. Bread wheat lines Francolin #1, Kenya Kongoni, Kundan and Sujata, and CIMMYT-derived durum wheat lines Bairds and Dunkler display an adequate level of adult plant resistance (APR) to both leaf rust and stripe rust in Mexican field environments. Six recombinant inbred line (RIL) populations developed from crosses Avocet/Francolin #1, Avocet/Kenya Kongoni, Avocet/Kundan, Avocet/Sujata, Atred#1/Bairds and Atred#1/Dunkler were phenotyped for leaf rust response at Ciudad Obregon, Mexico, and the bread wheat populations for stripe rust response at Toluca for under artificial inoculations for multiple seasons. The RIL populations and their parents were genotyped with the 50 K diversity arrays technology (DArT) sequence system and simple sequence repeat (SSR) markers. Known pleotropic APR genes Lr46/Yr29 mapped in all of six populations, and explained 7.4-65.1% and 7.7-66.1% severity variations for LR and YR across different bread wheat populations and accounted for 12.4-60.8% of LR severity variations over two durum wheat populations. In addition, several new APR loci identified on chromosomes 1AS, 1DS, 2BS, 2BL, 3D and 7BL in bread wheat and QTL on chromosome 6BL in durum wheat. Among these loci, QTL on chromosomes 1AS, 3D and 7BL might be represent new co-located/pleotropic loci conferring APR to LR and YR. RILs combining these APR loci can be used as sources of complex APR in both bread wheat and durum wheat breeding. In addition, the closely linked single nucleotide polymorphism (SNP) markers have been converted into breeder-friendly kompetitive allele specific PCR (KASP) markers and their diagnostic verified.

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Combining ability estimation for yield and yield related traits in Triticum aestivum

BGRI 2018 Poster Abstract
Nusrat Parveen Vegetable Research Institute AARI, Faisalabad, Pakistan.
Etlas,Amin, , , , , , , , , , , , , , , , , , , , , , , , , , , ,

In the present study five bread wheat genotypes (9797, 9801, 9802, Chakwal-50 and Chakwal-86) were tested in a 5?5 full diallel analysis for the estimation of combining ability for yield and its related traits. In randomized complete block design (RCBD) twenty F1s along with their parents were planted in field with three replications in the research area of Department of Plant Breeding and Genetics, University of Agriculture, during 2014-15. Plant height, No. of grains/spike, spike length, No. of productive tillers/plant, flag leaf area, No. of spikelets/spike, 1000 grain weight and grain yield per plant were studied. Except spike length mean squares due to GCA were highly significant for all the traits. All the characters showed highly significant mean squares for SCA and RCA. SCA variance was lower than GCA variance for number of grains/spike and spike length presenting the major role of additive gene action in the inheritance of these traits. While for plant height, flag leaf area, number of spikelets/spike, number of fertile tillers/plant, 1000 grain weight and grain yield/plant the value of GCA variance was lower than the value of SCA variance exhibiting non-additive gene action. Chakwal-50 was the best general combiner for plant height, spike length, number of spikelets/spike, number of grains/spike and grain yield/plant. The best specific combination for most of the traits was 9802?Chakwal-86. In future wheat breeding research programmes, good specific and general combiners can be exploited.

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Belonging identity of Puccinia striiformis f. sp. tritici population in Egypt

BGRI 2018 Poster Abstract
Ibrahim Draz Wheat Disease Research Department, Plant Pathology Research Institute, Agricultural Research Center, Giza, Egypt

Stripe rust (Puccinia striiformis f. sp tritici) (Pst) infected wheat samples collected from three Egyptian Governorates (Alexandria, Beheira and Kafr-El Sheikh) were processed for race analysis to determine the race identity among the current populations of the stripe rust fungus. Single uredinial isolates were inoculated to a core set of the 17 World/European differential hosts along with wheat lines with Yr17, Yr25, Yr32. Based on virulence phenotyping, the data revealed that the current populations of Pst belong to three races: Triticale aggressive (virulent to Yr2, Yr6, Yr7, Yr8, Yr10); PstS3 (virulent to Yr2, Yr6, Yr7, Yr8, Yr25); and PstS2 (virulent to Yr2, Yr6, Yr7, Yr8, Yr9, Yr25, Yr27). No collections were found with the Warrior race, that has virulence to Yr1, Yr2, Yr3, Yr4, Yr6, Yr7, Yr9, Yr17, Yr25, Yr32, YrSp).

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Gender Differences in Adoption of Improved Wheat Variety Technology in Kenya.

BGRI 2018 Poster Abstract
ANNE GICHANGI KENYA AGRICULTURAL AND LIVESTOCK RESEARCH ORGANIZATION (KALRO)
Godwin Macharia, Bernice Ngina

Studies have shown that women farmers are worse off than the male counterparts in terms of adoption of improved varietal technology and hence they experience low productivity. This technology adoption gender gap affects agricultural development considering that women in Kenya play a significant role in agriculture and food production. The link between gender and adoption is likely to vary across cultures and over time. The hypothesis of significant gender differences in access to and use of productive resources and adoption of improved wheat varieties was tested. Based on bivariate analysis, significant differences in access and use of productive resources between men and women farmers were observed. Men were more likely to access credit, extension services, own and cultivate more lands compared to women. Similarly, women in female-headed households were less likely to access the productive resources compared to women in male-headed households. The factors that affect adoption of improved wheat varieties among smallholder farmers were analysed with a specific focus on women. In contrast to the conventional model of using gender of the household head, gender and plot levels analyses were conducted. The results show that the gender of the field owner had a negative effect on adoption of improved wheat varieties. This indicates that, men were more likely to adopt improved wheat varieties, compared to women farmers. Moreover, the level of education of the household head, household size, and access to credit and extension services were observed to significantly increase the likelihood of farmers adopting improved wheat varieties. In the same framework, female farmers in male-headed households who had access to credit were more likely to adopt improved wheat varieties while there was greater probability of adoption of improved wheat varieties among female farmers in female-headed households who had access to agriculture extension and belonged to a farmer organization

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Study of the effect of planting date on the severity of yellow rust disease on bread wheat in northeastern Syria

BGRI 2018 Poster Abstract
Omran Youssef University of Hohenheim, Germany
Afrem,Issa, Helim, Youssef, Nawzad, Suleiman, Abdul Rahman, Issa, , , , , , , , , , , , , , , , , , , , , ,

Wheat is grown in Syria during the November-December. Wheat is exposed to many strains that negatively affect its productivity especially rust diseases, which was reported on wheat in Syria for many years and the most severe in 2010, Therefore, we studied the effect of planting dates on the severity and development of yellow rust disease. Where the field trials of the 2010-2011 season were carried out at the two locations in northeastern of Syria: Al-Qamishli Research Center and Yanbouh Research Station in Al-Malekia. By cultivating the susceptible bread wheat Cham 8, where six dates were planted starting from 02.10. 2010, a difference of 15 days. The results showed there was a difference in the severity of the yellow rust disease according to the dates of cultivation and thus the stages of growth in the plant and this was evident in the Yanbouh location where the onset of the onset of injury on 08.04.2011 in the all dates and developed the infection to 40S degrees and 30%. Also, on the 24. 04. 2011, the infection was recorded at the Qamishli location only on the third and fourth dates. The disease did not develop more than 10S and 10% due to climatic conditions due to rain and high temperature during the season. The results showed a positive correlation between the evolution of the disease and vegetative growth of plants, where the growth of plants was more active at the site of Yanbouh, especially in the second, third and fourth dates in the development of infection on plants in the rest of the dates because of weak and slow growth of plants.

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High yielding bread wheat cultivar Alaa with potential to retard rust spread in rain-fed and irrigated zones of Iraq

BGRI 2018 Poster Abstract
Emad Al-Maaroof Sulaimani University,IKR, Iraq

Rusts continue to cause significant losses in grain yield of wheat in Iraq. Substitution of susceptible cultivars with resistant ones is an important step in reducing the vulnerability of the wheat crop. The present study represents a breeding program to develop high yielding bread wheat cultivars with resistance to brown rust and yellow rust. The performance of 265 spring wheat genotypes representing an international bread wheat-screening nursery from CIMMYT were evaluated in different agro-ecological zones in comparison with local commercial cultivars. Adult plant stage screening of the materials for brown rust and yellow rust reaction under inoculated conditions for three successive seasons identified 29 resistant and 59 moderately resistant genotypes, and 79 genotypes out-yielded the local cultivars. The selected lines were comprehensively evaluated for grain yield potential and disease response in different locations and agro-systems. Among 13 genotypes line 172 was selected for higher grain yield than local commercial cultivars in the presence and absence of both diseases. Mean coefficients of infection on line 172 were 0.57 and 5.35 to brown rust and yellow rust, respectively. It was also moderately resistant to common bunt. Yield potential of the new cv. Alaa was 9-20% higher than the commercial local cultivars Araz, Tamuz 2 and Adana. Alaa was registered and released by the National Committee for Registration and Release of Agricultural Cultivars according to order no. 39, 30/10/2017 as a new cultivar with high yield potential and resistance to brown rust and yellow rust. Great emphasis was made on multiplication and delivery of seeds to farmers. Grain yield potential of Alaa on a farm scale is 3,372 Kg/ha under rain-fed conditions and 5,024 Kg/ha under irrigated conditions.

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Genomic scan in durum wheat reveals regions controlling adaptation to the heat-prone conditions of the Senegal River

BGRI 2018 Poster Abstract
Amadou Tidiane Sall ICARDA
Filippo,Bassi, Rodomiro, Ortiz, Ibrahima, Ndoye, AbdelKarim, Filali-Maltouf, Bouchra, Belkadi, Miloudi, Nachit, Michel, Baum, Hafssa, Kabbaj, Habibou, Gueye, Madiama, Cisse, , , , , , , , , ,

Wheat is a major food crop in West Africa, but its production is significantly affected by severe heat. Unfortunately, these types of high temperatures are also becoming frequent in other regions where wheat is commonly grown. In an attempt to improve durum wheat tolerance to heat, a collection of 287 elite breeding lines, including several from both ICARDA and CIMMYT, was assessed for response to heat stress in two irrigated sites along the Senegal River: Fanaye, Senegal and Kaedi, Mauritania during 2014-2015, and 2015-2016 winter seasons. The maximum recorded grain yield was 5t ha-1, which was achieved after just 90 days from sowing to harvesting. Phenological traits (heading, maturity and grain filling period) and yield components (1000-kernel weight, spike density and biomass) had also large phenotypic variation and a significant effect on grain yield performance. This panel was genotyped by 35K Axiom to generate 8,173 polymorphic SNPs. Genomic scans identified a total of 34 significant association between single nucleotide polymorphisms (SNPs) and traits across the four environments, including 15 related to phenological adaptation, 12 controlling grain yield components, and seven linked to grain yield per se. The identification of these genomic regions can now be used to design targeted crosses to pyramid heat tolerance quantitative trait loci (QTL), while the SNPs underlying these QTL can be deployed to accelerate selection process facilitated by DNA-aided breeding.

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Adaptability of Wheat Varieties in Strongly Acidic Soils of Sylhet in Search of Low pH Tolerant Wheat Variety

BGRI 2018 Poster Abstract
Ataur Rahman Wheat Research Centre, Bangladesh Agricultural Research Institute
,, , , , , , , , , , , , , , , , , , , , , , , , , , , ,

The soils of the entire Sylhet region of Bangladesh are strongly acidic where lands remain fallow during winter season due to scarcity of irrigation water required for rice cultivation. There is a scope of wheat expansion in this region as the water requirement of wheat is less than Boro rice. Field experimens were carried out at South-Surma, Sylhet, in 2012-13 and at FSRD site Jalalpur, Sylhet in 2013-14, in collaboration of WRC and OFRD. BARI examined the response of seven wheat varieties at two levels of lime in split-plot design where lime was applied in main plots and different wheat varieties were grown in sub-plots. The seeds were sown on December 05, 2012 and November 30, 2013 for the growing season of 2012-13 and 2013-14, respectively. The wheat varieties used in this study were Shatabdi, Sufi, Sourav, Bijoy, Prodip, BARI GOM 25 and BARI GOM 26. The index of relative performance of each variety in comparison to mean yield of all varieties under the contrast conditions of liming and non-liming was estimated to determine relative adaptability of wheat variety under experimental soil conditions. The result indicated that most of the yield components viz. spikes/m2, thousand grain weight and grain yield of wheat were significantly improved by liming for both the years and locations. There were variations in lime response among the wheat varieties. The index of relative adaptability (IRA%) for yield of BARI GOM 26 and Bijoy was more than 100% for both the years. The result indicated that these two wheat varieties are relatively tolerant to low pH and could be adapted in acidic soil of Sylhet.

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Virulence of Puccinia striiformis f. sp. tritici Population to 18 NILs in Yunnan Province, China

BGRI 2018 Poster Abstract
Mingju Li Institute of Agricultural Environment and Resources, Yunnan Academy of Agricultural Sciences, China
Xianming Chen, Anmin Wan, Jiasheng Chen, Mingliang Ding

Wheat stripe rust (Puccinia striiformis f. sp. tritici, Pst) is the most destructive disease of wheat worldwide. Breeding and planting resistant cultivars is the most economic, effective, as well as environmental methods to control the disease. Yunnan is a severe epidemic zone in China, which provides new incursions for other parts of China. Study on virulence of the Pst population and effectiveness of resistance genes, will provide information for breeding and rational use of resistance genes. One hundred and thirty-six136 isolates collected from 9 regions of Yunnan were tested using a set of 18 Yr NILs with genes Yr1, Yr5, Yr6, Yr7, Yr8, Yr9, Yr10, Yr15, Yr17, Yr24, Yr27, Yr32, Yr43, Yr44, YrSP, YrTr1, YrExp2, YrTyTye. Stripe rust races were named by octal code. The results showed that the Pst population in Yunnan is highly variable in races and virulence. A total of 64 races were identified and the top two most frequent races were 550273 (Virulence/Avirulence formula: 1, 6, 7, 9, 27, 43, 44, SP, Exp2, Tye / 5, 8, 10, 15, 17, 24, 32, Tr1 and 550073(Virulence/Avirulence Formula: 1, 6, 7, 9, 43, 44, SP, Exp2, Tye / 5, 8, 10, 15, 17, 24, 27, 32,Tr1), with frequency of 28.68% and 11.76%, respectively. The remaining races had frequencies less than 5.0%. No virulence were found for Yr5, Yr10, Yr15, and Yr32. The frequencies of virulence to Yr24, YrTr1, Yr8, and Yr17 ranged from 0.74% to 11.76%. The frequency of virulence to Yr27 was 52.94%; and virulence to Yr1, Yr6, Yr7, Yr9, Yr43, Yr44, YrSP, YrExp2, and YrTye ranged from 79.94% to 91.91%. The results will guide the breeding and wheat production. (This study was supported by National Natural Science Foundation of China, Grant No. 31260417 and 31560490)

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Innovative manufacturing of a cereal rust inoculation device

BGRI 2018 Poster Abstract
Zak Pretorius University of the Free State
Gerrie Booysen, Willem Boshoff, Jozua Joubert

Urediniospores of rust fungi can be applied to cereal plants in several ways. Depending on the objective and available infrastructure, plants can be inoculated with a suspension of spores in either water, light mineral oil (e.g. Soltrol 130®) or engineered fluid (e.g. Novec 7100®). Alternatively, dry spores can be allowed to settle on plant surfaces by dusting or directly applied with a spatula or small brush. Several rust laboratories employ a system where a spore-oil suspension, contained in a gelatin capsule, is sprayed onto seedling leaves by means of a dedicated atomizer connected to an air pressure source. Although this approach is easy to use and highly efficient, the devices are not commercially available in South Africa. Locally, these inoculation appliances need to be manufactured by a conventional milling process that requires a specialized workshop and skilled personnel. This subtractive process is labour intensive and greatly prohibitive in terms of costs. Using a process called Additive Manufacturing (AM), also known as "3D printing", the body of an inoculator was digitally designed and then laser sintered in nylon. Loose powder was removed from flow channels by compressed air. A copper tube fitted afterwards connected the nylon body with the spore suspension in the capsule. Replicated inoculation tests of wheat seedlings with urediniospore bulks or single pustule collections of Puccinia triticina and P. graminis f. sp. tritici resulted in consistent levels of rust severity and infection frequency. Cleaning of inoculators in acetone for 1 min followed by a 1 h heat treatment at 60°C produced no contaminant infection in follow-up tests. The design has been registered in South Africa, the USA and Europe.

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