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COVID-19 has exposed the vulnerability of our economies to shocks, and it has laid bare deep inequalities in our society that threaten to derail the Sustainable Development Goals. Governments around the world are looking for recovery options that deliver new jobs and businesses. Few sectors link job creation so closely to sustainable green production as the food sector. It is the largest source of employment in many countries in the global South. At the same time cities depend upon imported food that is produced in far-away countries and shipped around the world. The trillions of dollars to be invested in recovery from COVID-19 offers an unprecedented opportunity for a clean, green and just transition to a more biodiversity-friendly agricultural and food system. Key among the political opportunities to shift the post-pandemic world towards sustainability and resilience are the ongoing deliberations of the Post-2020 Global Biodiversity Framework. The Post-2020 Framework will be the precedent for national governments to bridge economic action with the key need for a green, resilient recovery. The United Nations Convention on Biological Diversity (CBD) has traditionally seen agriculture as one of the biggest threats to biodiversity and has been actively promoting the protection of natural ecosystems by concentrating its efforts on preventing further expansion of agriculture. But it has not explicitly recognized the importance of mixed, diverse agricultural landscapes for their contribution to the conservation of wild biodiversity. The CBD has an opportunity to bring its influence to bear on international policy favouring investments in local production and marketing capacity to replace imported food and beverages. This will contribute to both COVID-19 recovery through creation of rural jobs and income and empowering governments and consumers to support diverse, mixed agricultural systems that conserve and enhance biodiversity as well as reduce greenhouse gas emissions.

Transgenic plants harboring the left transfer DNA (TL-DNA) of the root inducing plasmid of Agrobacterium rhizogenes show many developmental abnormalities. We observed frequent appearance of normal looking lateral (revertant) shoots from such aberrant plants. Unlike aberrant shoots of the plant, revertant shoots exhibited a very high growth rate and set viable seeds. Sexual and vegetative reproduction studies showed inheritance of the revertant phenotype. Southern hybridization experiments demonstrated that the T-DNA pattern was identical in aberrant and revertant shoots, indicating that the revertant phenotype was not due to deletion or rearrangement of the T-DNA genes. Specific T-DNA transcripts were not expressed in revertant shoots. Thus, the revertant phenotype appears to result from the transcriptional inactivation of T-DNA genes. We propose that similar events in the past may have mediated horizontal acquisition of TL-DNA genes by ancestors of the genus Nicotiana, which are still found as silent endogenous T-DNA in present day untransformed Nicotiana species.

A variant clone of Hyoscyamus muticus (VIIIB9) with a specific, stable requirement for tryptophan has been shown to have the following characteristics: (i) no accumulation of tryptophan from anthranilic acid; (ii) growth on added tryptophan or indole but not on anthranilic acid; (iii) accumulation of indole-3-glycerol phosphate and other indole derivatives; (iv) extractable activity of the enzymes for tryptophan biosynthesis, including the partial reaction 2 of tryptophan synthase but not reactions 1 or 3. Thus these data provide in-vivo evidence for the existence of a two-component, bacterial-type tryptophan synthase in plants, the tryptophan auxotrophy of VIIIB9 probably being the consequence of a mutation in the α-subunit of the tryptophan-synthase complex.