International Maize and Wheat Improvement Center

About: International Maize and Wheat Improvement Center is a nonprofit organization based out in Texcoco, Mexico. It is known for research contribution in the topics: Population & Agriculture. The organization has 1976 authors who have published 4799 publications receiving 218390 citations.

The effects of iron plaque and phosphorus on yield and arsenic accumulation in rice

Abstract: The effects of arsenate, Fe2+, and phosphate on amount and composition of Fe-oxide plaque at the rice-root surface and on the yield and arsenic accumulation in rice (cv. BRRI dhan33) were studied in a replicated pot-culture experiment. Arsenic in the form of Na2HAsO4 was applied at concentrations of 0, 15 and 30 mg kg−1 in combination with P and/or Fe at 0 and 50 mg kg−1, from KH2PO4 and FeSO4, respectively. Root, grain and straw yields and their As, Fe and P concentrations were determined. The Fe-oxide plaque was extracted from the plant roots using dithionite-citrate-bicarbonate (DCB) and NH4-oxalate extractions. The addition of Fe2+ reduced the toxic effect of As in flooded-rice culture and resulted in reduced grain-As accumulation and increased grain yields. The effect of applied phosphate was the opposite, in that it resulted in higher As concentrations in both grain and straw and lower grain yields. The effects of both Fe and P can be explained based on their impacts on adsorption of As onto soil and rice-plaque Fe-oxides and the subsequent As solubility and availability for uptake by rice. These reactions have important implications to rice-crop management and the natural variability in soils and irrigation-water characteristics that might impact As uptake by rice.

Molecular mapping of stripe rust resistance gene YrCH42 in Chinese wheat cultivar Chuanmai 42 and its allelism with Yr24 and Yr26.

Abstract: Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most devastating diseases in common wheat (Triticum aestivum L.) worldwide. The objectives of this study were to map a stripe rust resistance gene in Chinese wheat cultivar Chuanmai 42 using molecular markers and to investigate its allelism with Yr24 and Yr26. A total of 787 F2 plants and 186 F3 lines derived from a cross between resistant cultivar Chuanmai 42 and susceptible line Taichung 29 were used for resistance gene tagging. Also 197 F2 plants from the cross Chuanmai 42·Yr24/3*Avocet S and 726 F2 plants from Chuanmai 42·Yr26/3*Avocet S were employed for allelic test of the resistance genes. In all, 819 pairs of wheat SSR primers were used to test the two parents, as well as resistant and susceptible bulks. Subsequently, nine polymorphic markers were em- ployed for genotyping the F2 and F3 populations. Re- sults indicated that the stripe rust resistance in Chuanmai 42 was conferred by a single dominant gene, temporarily designated YrCH42, located close to the centromere of chromosome 1B and flanked by nine SSR markers Xwmc626, Xgwm273, Xgwm11, Xgwm18, Xbarc137, Xbarc187, Xgwm498, Xbarc240 and Xwmc216. The resistance gene was closely linked to Xgwm498 and Xbarc187 with genetic distances of 1.6 and 2.3 cM, respectively. The seedling tests with 26 PST isolates and allelic tests indicated that YrCH42, Yr24 and Yr26 are likely to be the same gene.

High-Throughput Estimation of Crop Traits: A Review of Ground and Aerial Phenotyping Platforms

Abstract: Crop yields need to be improved in a sustainable manner to meet the expected worldwide increase in population over the coming decades as well as the effects of anticipated climate change Recently, genomics-assisted breeding has become a popular approach to food security; in this regard, the crop breeding community must better link the relationships between the phenotype and the genotype While high-throughput genotyping is feasible at a low cost, high-throughput crop phenotyping methods and data analytical capacities need to be improved