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High-oil tobacco varieties have been recently engineered to produce increased leaf oil content for future food and fuel needs. An engineered variety of Nicotiana tabacum produces ~30 percent of leaf dry weight in lipids in the form of triacylglycerol (TAG), a significant increase relative to the less than 1 percent storage oil normally found in wild-type leaves. This high-oil tobacco also accumulates oil bodies in stomatal guard cells. In order to understand the impact of oil on guard cell shape, aperture, and dynamics, we have co-opted computer vision tools in PlantCV to create an accurate, flexible, and high-throughput method for microscopy image analysis of stomata. To this end, leaf impressions are made with silicone putty; clear nail polish peels of the putty impressions are imaged using light microscopy. Binary thresholding followed by point-and-click regions of interest and morphology calculations provide stomatal counts, aperture, and other shape characteristics. Applying this method to high-oil tobacco demonstrated reduced stomatal aperture but the same number of stomata per unit leaf area, providing a mechanistic explanation of high-oil tobacco responses to high temperature and water deficit stresses.

Tef is a staple food and a valuable cash crop for millions of people in Ethiopia. Lodging is a major limitation to tef production, and for decades, the development of lodging resistant varieties proved difficult with conventional breeding approaches. We used CRISPR/Cas9 to introduce knockout mutations in the tef orthologue of the rice SEMIDWARF-1 (SD-1) gene to confer semidwarfism and ultimately lodging resistance. High frequency recovery of transgenic and SD-1 edited tef lines was achieved in two tef cultivars by Agrobacterium-mediated delivery into young leaf explants of gene editing reagents along with transformation and regeneration enhancing morphogenic genes, BABY BOOM (BBM) and WUSCHEL2 (WUS2). All of the 23 lines analyzed by next-generation sequencing had at least two or more alleles of SD-1 mutated. Of these, 83% had tetra-allelic frameshift mutations in the SD-1 gene in primary tef regenerants, which were inherited in subsequent generations. Phenotypic data generated on T