The Effect of Several Mineral Fertilizers Upon the Nondulation of Virginia Soy Beans

Paddy husk ash as a source of potassium for growth and yield of cowpea (<i>Vigna unguiculata</i> L.)

“…The result obtained is similar to Collins and Duke (1981) who revealed that in legumes, potassium deficit may cause inadequate supply of sugars to root nodules, which greatly reduces rates of N 2 fixation and export of bound nitrogen. Further, Seripong (1988) who concluded that phosphorous and rice husk ash improved nodulation in Thailand soils, and Perkins (1924) indicated increase in soyabean nodulation with potassium fertilizer and liming. This is also confirmed by Poschenrieder and Lesch (1943) who reported that potassium enhances the nodulation of soyabean.…”

Nodulation Responses of Soybeans to Added Phosphorus, Potassium, and Calcium Salts1

“…As in many other previous studies, the low numbers of nodules observed suggest restrictions due to chosen environmental conditions. Perkins (11) on the other hand decided that P was nonessential for nodulation. He conducted pot trials with two soils and one with quartz sand.…”

“…When the rate of K was doubled, nodulation was impaired in their field experiments. Perkins ( 11) ( 12) reported positive K effects above a certain rate of P application and negative effects below that. K depressed the N content of the nodules.…”

The influence of zone-placed phosphorus fertilizer on yield, leaf composition, and nodulation of soybean varieties

“…As early as 1918 Fellers reported that P fertilization in creased nodulation in soybeans, and that the response was most pronounced on limed soils. However, Perkins (1924) did not observe increased nodulation due to P in a pot culture study.…”