Heterosis in rice; Rice cytoplasmic-genetic male sterility system; Procedures for breeding hybrid rice; Breeding for CMS lines and their maintainers; Breeding for restorer lines; Hybrid seed production and CMS line multiplication; Purifying parental lines and producing foundation seeds; hybrid rice cultivation practices; Breeding two-line system hybrid rice; Studies on one-line system hybrid rice development.

This symposium is a follow-up to one held in China in 1986. Since then considerable progress has been made in research and development of hybrid rice. This second international symposium was held under the umbrella of the International Rice Research Conference. Eighty scientists and seed production experts from 18 countries, IRRI and FAO attended. Contributions covered breeding, biotechnology, seed production, agronomy, plant physiology, plant pathology, entomology and economics.

In 1964 a Chinese rice breeder, Yuan Longping, discovered a rice plant that was the genetic key to the successful development of high yielding hybrid rice. At that time, China was a secretive communist state where self pollinating varietal rice was grown on collective farms using highly labor intensive practices. Forty years later, by 2004, hybrid rice, based on Yuan's work, was being grown commercially in the United States using mechanized farming practices. This book describes the journey across those four decades and the chain of events and people which resulted in technical success in China by 1976 and in the United States by 2000. Extraordinary political and technological developments occurred during this time and the book describes these and the many serendipitous events and people of different backgrounds that were involved in the successful journey. It is estimated that hybrid rice is now (2017) saving the US rice industry as much as $100 million each year.

Assessing impacts of public investments has long captured the interest and attention of the development community. This paper presents the evolution of different methods and approaches used for ex ante appraisal, monitoring, project evaluation, and impact assessment over the last five decades. Among these tools, impact assessment (IA) conducted retrospectively comes closest to providing the proof of development effectiveness. It is defined as the systematic analysis of the significant or lasting changes in people's lives brought about by a given action or series of actions in relation to a counterfactual. There are three basic types of retrospective IAs: macro-level IAs that focus on the contribution of developmental efforts to an impact goal aggregated at a sector or a system level; micro-level impact evaluations (IEs) concerned with estimating the average effect of an intervention on outcomes at the beneficiary level; and micro-level ex post impact analysis concerned with total effects of a development effort after the outputs are scaled-up. Ex post IAs have evolved and expanded over the decades in both breadth and depth of analysis in response to evolving development themes and methodological advancements. The increased emphasis on learning from evaluations has also seen responses from both quantitative and qualitative camps of the evaluation community. The paper argues that generation of robust knowledge that feeds into making developmental policies and investment decisions requires a hierarchical and cumulative approach to "improving the proof" through rigorous and a variety of impact assessment methods applied incrementally at the project, program and system level. Subjecting as many development interventions as resources allow to rigorous impact assessment based on a common framework can help build a critical body of evidence on impacts of development interventions, which can then be subjected to meta-analyses to help assimilate results across different studies and build a knowledge base on what works and what does not.