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The management of pesticides to protect water quality remains a significant global challenge. Historically, despite regulatory frameworks intended to prevent, minimize, and manage off-site movement of pesticides, multiple generations of pesticide active ingredients have created a seemingly unending cycle of pesticide water pollution in both agricultural and urban watersheds. In California, the most populous and most agricultural US state, pesticide and water quality regulators realized in the 1990s that working independently of each other was not an effective approach to address pesticide water pollution. Over the years, these California agencies have developed a joint vision and have continued to develop a unified approach that has the potential to minimize pesticide risks to aquatic life through a combination of prevention, monitoring, and management actions, while maintaining pesticide availability for effective pest control. Key elements of the current California pesticide/water quality effort include: 1) pesticide and toxicity monitoring, coupled with watershed modeling, to maximize information obtained from monitoring; 2) predictive fate and exposure modeling to identify potential risks to aquatic life for new pesticide products when used as allowed by the label or to identify effective mitigation measures; and 3) management approaches tailored to the different pesticide uses, discharge sources, physical environments, and regulatory environments that exist for agricultural runoff, urban runoff, and municipal wastewater. Lessons from this effort may inform pesticide management elsewhere in the world as well as other chemical regulatory programs, such as the recently reformed US Toxic Substances Control Act and California's Safer Consumer Products regulatory program. Environ Toxicol Chem 2020;39:953-966. © 2020 SETAC.

The loss of biological diversity of crops in centers of crop origins and evolution ("Vavilov centers") is recognized as a cost of agricultural modernization. Another effect is to alter processes of crop evolution by restructuring farmer seed management. This article uses two case studies of "traditional" and "developed" agriculture to examine crop diversity and the management of crop evolutionary processes. The Mexican milpa is regarded as a descendant of Mesoamerican agriculture within which crop evolution of maize, beans, squash, and numerous other species developed and acquired diversity. Here, farmer-based selection prevails. California peach orchards are far removed from the original region of peach domestication, evolution, and diversity. Here, breeder-based selection prevails. The contrast is intended to show three things. First, farmer-based selection versus breeder-based selection is not necessarily a contrast of diverse versus not diverse farming systems. Second, agricultural development, includ...

Teff is domesticated in Ethiopia and is locally important. Seventy accessions of teff collected from seven regions have been sown in a balanced block design. Significant and highly significant variation was observed between regions, within region and between individual plants within accession for most of the characters considered. Regions showed variations for different characteristics indicating that every region may contribute valuable genotypes for teff improvement programs.