Harnessing translational research in wheat for climate resilience.

Despite being the world's most widely grown crop, research investments in wheat (Triticum aestivum and Triticum durum) fall behind those in other staple crops. Current yield gains will not meet 2050 needs, and climate stresses compound this challenge. However, there is good evidence that heat and drought resilience can be boosted through translating promising ideas into novel breeding technologies using powerful new tools in genetics and remote sensing, for example. Such technologies can also be applied to identify climate resilience traits from among the vast and largely untapped reserve of wheat genetic resources in collections worldwide. This review describes multi-pronged research opportunities at the focus of the Heat and Drought Wheat Improvement Consortium (coordinated by CIMMYT), which together create a pipeline to boost heat and drought resilience, specifically: improving crop design targets using big data approaches; developing phenomic tools for field-based screening and research; applying genomic technologies to elucidate the bases of climate resilience traits; and applying these outputs in developing next-generation breeding methods. The global impact of these outputs will be validated through the International Wheat Improvement Network, a global germplasm development and testing system that contributes key productivity traits to approximately half of the global wheat-growing area.

Effect of institution-wide policy of colonoscopy withdrawal time > or = 7 minutes on polyp detection.

BACKGROUND & AIMS: Practice guidelines recommend that endoscopists spend at least 7 minutes examining the colonic mucosa during colonoscopy withdrawal to optimize polyp yield. The aim of this study was to determine if the implementation of an institution-wide policy of colonoscopy withdrawal time > or = 7 minutes was associated with an increase in colon polyp detection. METHODS: All 42 endoscopists at our institute were asked to attain a colonoscopy withdrawal time of at least 7 minutes. Compliance with 7-minute withdrawal time was recorded for all nontherapeutic colonoscopies. Polyp detection ratio (number of polyps detected divided by number of colonoscopies performed) was computed. Regression models were used to assess the association between compliance with 7-minute withdrawal time and polyp detection. RESULTS: During the study period, 23,910 colonoscopies were performed. The average age of patients was 56.8 years, and 54% were female. Colon cancer screening or surveillance was the indication for 42.5% of colonoscopies. At the beginning of the study, the polyp detection ratio was 0.48. Compliance with 7-minute withdrawal time for nontherapeutic procedures increased from 65% at the beginning of the initiative to almost 100%. However, no increase in polyp detection ratio was noted over the same period for all polyps (slope, 0.0006; P = .45) or for polyps 1-5 mm (slope, 0.001; P = .26), 6-9 mm (slope, 0.002; P = .43), or > or = 10 mm (slope, 0.006; P = .13). No association was detected when only colonoscopies performed for screening or surveillance were analyzed. CONCLUSIONS: An institution-wide policy of colonoscopy withdrawal time > or = 7 minutes had no effect on colon polyp detection.

Overexpression of the maize Teosinte Branched1 gene in wheat suppresses tiller development.

The number of viable shoots influences the overall architecture and productivity of wheat (Triticum aestivum L.). The development of lateral branches, or tillers, largely determines the resultant canopy. Tillers develop from the outgrowth of axillary buds, which form in leaf axils at the crown of the plant. Tiller number can be reduced if axillary buds are not formed or if the outgrowth of these buds is restricted. The teosinte branched1 (tb1) gene in maize, and homologs in rice and Arabidopsis, genetically regulate vegetative branching. In maize, increased expression of the tb1 gene restricts the outgrowth of axillary buds into lateral branches. In this study, the maize tb1 gene was introduced through transformation into the wheat cultivar "Bobwhite" to determine the effect of tb1 overexpression on wheat shoot architecture. Examination of multiple generations of plants reveals that tb1 overexpression in wheat results in reduced tiller and spike number. In addition, the number of spikelets on the spike and leaf number were significantly greater in tb1-expressing plants, and the height of these plants was also reduced. These data reveal that the function of the tb1 gene and genetic regulation of lateral branching via the tb1 mode of action is conserved between wheat, rice, maize and Arabidopsis. Thus, the tb1 gene can be used to alter plant architecture in agriculturally important crops like wheat.