In the past 15–20 years, the employment of Plant-Growth-Promoting Bacteria (PGPB) to facilitate the growth of agricultural food crops has increased dramatically. These beneficial soil bacteria, whose use and demonstrations of efficacy have previously been largely limited to the laboratory, have now been shown to be effective under field conditions. In addition, the mechanisms that these bacteria utilize to facilitate plant growth are now mostly well characterized. Moreover, several companies across the globe have commercialized a number of PGPB and there is every indication that this trend will continue to grow. As a consequence of these developments, in this review article, a large number of recent reports on the successful testing of many different types of PGPB and their effects on various food crops is discussed.

No abstract

Synopsis Nitrogen and sulfur fertilization did not appreciably affect the uptake of phosphorus by alfalfa from rock phosphate. Alfalfa yield increases due to rock phosphate and superphosphate were not significantly different on unlimed soil. But, on limed soil superphosphate was significantly better than rock phosphate.