Assessing the returns to R&D on perennial crops: the costs and benefits of Pi…

Several complicating issues arise in evaluating the returns to research into varietal improvements for perennial crops compared with annual crops. We elucidate and address these issues in the context of a case study of research aiming to develop varieties that are resistant to Pierce’s disease (PD) of grapevines. PD imposes costs of over $100 million per year on the California grape industry,…