ABSTRACT
This chapter describes the new understandings and applications with higher plants due to their world-wide agricultural importance. It utilizes e the word efficiency in a functional manner to describe the effectiveness of plants in advantageously using photosynthesis in producing a product such as seeds or in utilizing a resource such as carbon-di-oxide or water or soil nitrogen. Maximum short-time growth rates should be reflected in the yield of a crop; it is difficult to maintain optimum plant growth conditions throughout the lifetime of a crop. H. R. Boerma and associates have studied canopy photosynthesis and yield with determinate soybean varieties. They find positive correlations between canopy photosynthesis and seed yield sufficiently high to be used in selection for yield. Net seasonal canopy photosynthesis is positively correlated with seed yield in soybeans. Selection for high total canopy photosynthesis combined with selection for high harvest index is recommended for increasing yields in plant breeding improvement work.
