Effects of low molybdenum seed on nodule initiation, development and N2 fixation in black gram (Vigna mungo L.)

Abstract

In legumes, both increases and decreases in nodule number in response to Mo deficiency have been reported, but reasons for the different responses have not been proposed. The present study examined nodule initiation and development in black gram seedlings using two levels of seed Mo to induce Mo deficiency. In the first 11 days after inoculation, low levels of Mo in seed had no effect on nodule initiation or the number of nodules. At 13 days after inoculation, low Mo in seed depressed bacteroid concentration, leghaemoglobin concentration, nodule number and nodule fresh weight. Acetylene reduction activity was delayed by 2 days in plants grown from low Mo seed. We suggest that the delay in N 2 fixation in plants grown from low Mo seed was due to slower incorporation of Mo of soil origin into nitrogenase. We further suggest that restricted supply of essential metabolites to the nodules on plants from low Mo seed resulted in the slower maturation of early initiated nodules and the repression of formation of new nodules.

Growth and Yield of Common Bean (Phaseolus Vulgaris L.) in Response to Rhizobium Inoculation, Nitrogen and Molybdenum Fertilization

“…Molybdenum also participates as co -factor of nitrogenase, responsible for biological nitrogen fixation. Jongruaysup et al (1993) stated that crops developing symbiosis with rhizobium bacteria had increased molybdenum requirements. Deficiency of this element causes a reduction of nodulation and nitrogen fixation.…”

Effect of Rhizobium Inoculation Under Bio- And Mineral Fertilization and Their Interaction on Quality and Quantity of Soybean (Glycine Max L.)

“…the enzyme nitrogenase contained two proteins ; Mo-Fe protein (component containing iron and protein) and Fe protein (component containing iron and protein) . Jongruaysup et al (1993) stated that crops developing symbiosis with Rhizobium bacteria had increased molybdenum requirements . Deficiency of this element causes a reduction of nodule dry weight .…”

Residual Effect of Organic and Inorganic Fertilizers on Growth Indices of Chickpea under Soybean-Chickpea System in Vertisol of Central India

“…Thus, molybdenum is key to nitrogen fixation by legumes. Molybdenum stimulates nodulation and biological nitrogen fixation (Brkics et al 2004; Jongruaysup et al [20] and ascorbic acid synthesis is implicated in the physiological availability of iron [21]. "It also facilitates diverse physiological and biochemical processes, including photosynthesis as well as carbohydrate and sulfur metabolism.…”