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The International Maize and Wheat Improvement Center (CIMMYT) aims to genetically enhance both crops and generate public sector-provided products for the resource poor, e.g., drought tolerant wheat and insect resistant maize, and through international–national partnerships facilitate the acquisition of improved germplasm for non-mandate crops in the cropping systems where maize and wheat thrives; e.g., GM-papaya through a national food security undertaking in Bangladesh. The Center also engages in public awareness campaigns in projects such as Insect Resistance Maize for Africa (IRMA), which includes food, feed and environmental safety, monitoring of resistance and establishment of refugia, non-target effects and gene flow. Monitoring of genetic resources is a wide concern among the centers of the Consultative Group on International Agricultural Research (CGIAR), with an emphasis on the quality of gene banks. Decisions, policies and procedures about monitoring should be science-based, and this requires education, an area where CIMMYT and other CGIAR centers can play an important role. There will be a need to continue to evaluate the need for, and type of monitoring, as new (and unique) products are developed and released in the emergent economies of the world. [ABSTRACT FROM AUTHOR]

Comparative genetic analysis has shown that different plant species often share orthologous genes for very similar functions, especially for cereal crops. In this study, we focused on analyzing the utility of EST-SSR markers among monocots in silico and by experiment. Based on 423,611 wheat ESTs, 101,299 were found to express commonly in rice, maize and barley ESTs, which accounted for 23.94% of wheat EST data. 1707 SSR-containing ESTs (SSR-ESTs) were mined from the 101,299 homologous ESTs, which accounted for 8.8% of all the 19,434 wheat EST-SSRs. It showed that the number of homologous SSR-ESTs much less than the homologous ESTs among grasses. The number of conserved ESTs and SSR-ESTs were inversely proportional to the evolutionary distance among species. Although these SSR-ESTs were in high similarity, the number of conserved SSRs between wheat and the other three crops decreased with the increased aligning regions, and only 13 types of SSR motifs in 21 ESTs were obtained by aligning sequences over a stretch of more than 40 bp. The variation at a microsatellite came from not only the differences in the numbers of repeat units and its location shift, but also base mutations flanking microsatellite repeats. From the 428 uni-SSR-ESTs universally in the four cereals, 243 primers were designed and tested in two genotypes of each species. 154 (63.4%) primers produced clear amplicons across the four species, which showed a high efficient transferability of wheat EST-SSR markers to the other three cereal crops. [ABSTRACT FROM AUTHOR]

Doubled haploid (DH) lines are important in wheat (Triticum aestivum L.) breeding, and haploids produced via maize pollination precede DH line development. Although maize pollination has proven reliable and broadly applicable to wheat, its success is determined by the wheat and maize genotypes employed. A wheat genotype consisting of nuclear and cytoplasm components predisposing it to parthenogenesis was compared with three other genotypes, each possessing only one or neither component necessary for parthenogenesis. In a glasshouse experiment, each genotype was pollinated with maize and subsequently treated with a 2,4-Dichlorophenoxyacetic Acid (2,4-D) solution to determine if parthenogenesis affected embryo formation frequency (EFF) and haploid formation efficiency (HFE). Wheat genotypes were also treated with the 2,4-D solution alone to determine if embryos and haploid plants could be produced in vivo without maize pollination. `Salmon(K)', a parthenogenetic genotype consisting of a Salmon 1BL.1RS nucleus in a Ae. kotschyii cytoplasm, had a mean EFF of 32%; whereas, the non-parthenogenetic genotypes had mean EFF calculations ranging from 7 to 21%. Mean HFE for Salmon(K) was not significantly different than the mean HFE for non-parthenogenetic Salmon; however, EFF and HFE calculations for Salmon(K) and Salmon, each with a 1BL.1RS translocation, were generally higher than calculations for genotypes without the translocation. Salmon(K) was the only genotype to produce a 3% or higher EFF and HFE after treatment with 2,4-D alone. Parthenogenesis significantly affected the frequency at which embryos were produced after pollination with maize and the frequency at which embryos and haploid plants were produced after treatment with 2,4-D alone. [ABSTRACT FROM AUTHOR]