Response of Nodulated and Nonnodulated Soybean Seedlings to Sulfur Nutrition¹

Abstract

Sulfur deficiency decreased growth and concentrations of nonsoluble N and soluble protein N, increased concentrations of nonprotein N and free amino acids, and had little effect on nitrate N in soybean seedlings. Amide N concentration increased and nitrate reductase activity decreased only in S‐deficient nonnodulated seedlings grown with nitrate N source. Ammonia N concentration increased only in S‐deficient nodulated seedlings grown without an available N source. Nodule hemoglobin concentration was affected little, but nodule quantity and total N2 fixed were decreased markedly by S deficiency. The capacity of soybean seedlings to fix N2 was less than their ability to utilize nitrate N.

Enhancing Soybean Yield: The Synergy of Sulfur and Rhizobia Inoculation

“…In contrast, non-nodulated soybeans showed no impact on nitrogen metabolism and content under sulfur deficiency. This contrasts with our findings, possibly due to Wooding et al [51] not observing the entire soybean reproductive period. Our study revealed that nitrogen accumulation in shoots and roots of non-nodulated soybeans remained unaffected by sulfur concentration during the early growth stages (V9).…”

“…Even when inoculated with Rhizobium, a sulfur concentration of 0 mM failed to produce root nodules, significantly reducing nitrogen accumulation and soybean shoot biomass. Wooding et al [51] reported that sulfur deficiency inhibited nitrogen fixation and nitrogen metabolism in nodulated soybeans, leading to decreased nitrogen content. In contrast, non-nodulated soybeans showed no impact on nitrogen metabolism and content under sulfur deficiency.…”

Effect of Lime, Sulfur, and Molybdenum on N2 Fixation and Yield of Dark Red Kidney Beans1

“…Oke (1969) applied S to pigeon pea (Cajanus cajan) and guar (Cyamopis tetragondoba) and measured the nitrogen content of the roots, shoots, and nodules by the Kjeldahl procedure. He found that N content of the nodules and percent N in the plants were significantly increased by S. Wooding, Paulsen, and Murphy (1970) measured the difference in total N content of symbiosis-dependent soybean seedlings at time of transplanting and at the end of 3 weeks. They found that seedlings grown in nitrogen-free nutrient solution plus S contained 2.5 times more nitrogen than those without S.…”

Effect of nitrogen and sulphur application and seed inoculation with Rhizobium leguminosarum on the yield of beans (Vicia faba) in field trials

“…This effect was independent of those derived from the other treatments. Wooding et al (1970) found that sulphur deficiency reduced the growth of soya beans and that added sulphur increased the nodule size and the amount of nitrogen fixed. Similar results have been found for other legumes (Spencer, 1975).…”

“…Sulphur is an essential nutrient for legumes (Oke, 1969;Spencer, 1975). It has been suggested that it has an important role in nodulation and nitrogen fixation (Wooding, Paulsen & Murphy, 1970;Janssen & Vitosh, 1974;Gates & Miller, 1979). However, most of the studies have been made using sulphur as sulphate, although some experiments using sulphur as elemental form by foliar application have been reported (Lluch, Gomez & Olivares, 1976).…”