what is the use of root nodes in the leguminous plants?

Question

The nodes in a leguminous plants filled with bacteria eg.azetobactor & rizobium. These bacteria convert the natural nitrogen into nitrates in our atmosphere.

Answer 1

Legume plants are noteworthy for their ability to fix atmospheric nitrogen, an accomplishment attributable to a symbiotic relationship with certain bacteria known as rhizobia found in root nodules of these plants. The ability to form this symbiosis reduces fertilizer costs for farmers and gardeners who grow legumes, and means that legumes can be used in a crop rotation to replenish soil that has been depleted of nitrogen.

Answer 2

You seem to have a good understanding of this. In the nitrogen cycle ammonium and nitrates are constantly converted to atmospheric nitrogen by soil bacteria. Apart from lightening legumes are the only way nitrogen is converted back to a usable form in nature. Man converts a lot of nitrogen to nitrates via the Haber process. Unfortunately we use a lot of it for munitions however the increase in crop yields that are possible with nitrogen fertilisers allows many more people to survive. The atmosphere is about 80% nitrogen, 20% oxygen and a tiny% of other gasses including Carbon Dioxide.

Answer 3

The process taking place here is symbiosis- two organisms living each other with mutual give and take. The bacteria by te process of nitogen fixation provide the plant with nitrates in the soil which are otherwise unavailable.In return the plant gives shelter to the bacteria and food which is drawn from the soil through roots and in addition to this the root nodules being inside the soil are safer than exterior regions.

Answer 4

Root nodules occur on the roots of plants that associate with symbiotic bacteria.

Under nitrogen limiting conditions, plants from the pea family Fabaceae form a symbiotic relationship with a host-specific strain of bacteria known as rhizobia.

Two main types of nodule have been described.

Temperate legumes like Pisum, Medicago, Trifolium, and Vicia develop a cylindrical shaped nodule that is called "indeterminate" because it maintains an active apical meristem that produces new cells for growth over the life of the nodule. The genus Lupinus is nodulated by the soil microorganism Bradyrhizobium sp. (Lupinus). Bradyrhizobia are encountered as microsymbionts in other leguminous crops (Argyrolobium, Lotus, Ornithopus, Acacia, Lupinus) of Mediterranean origin

Tropical (sub)legumes from the genera Glycine, Phaseolus, Lotus, and Vigna form "determinate" nodules, that lose meristematic activity shortly after initiation. Growth is due to cell expansion, and mature nodules are spherical in shape.

Legumes release compounds called flavonoids from their roots, which trigger the production of nod factors by the bacteria. When the nod factor is sensed by the root, a number of biochemical and morphological changes happen: cell division is triggered in the root to create the nodule, and the root hair growth is redirected to wind around the bacteria multiple times until it fully encapsulates 1 or more bacteria. The bacteria encapsulated divide multiple times, forming a microcolony. From this microcolony, the bacteria enter the developing nodule through a structure called an infection thread, which grows through the root hair into the basal part of the epidermis cell, and onwards into the root cortex; they are then surrounded by a plant-derived membrane and differentiate into bacteroids that fix nitrogen.

Root nodules that occur on non-legume genera like Parasponia in association with Rhizobium bacteria, and those that arise from symbiotic interactions with Actinobacteria Frankia in some plant genera such as Alnus, vary significantly from those formed in the legume-rhizobia symbiosis. In these symbioses the bacteria are never released from the infection thread.

Retrieved from "http://en.wikipedia.org/wiki/Root_nodule"

Answer 5

root nodules of leguminous plants r associated with nitrogen fixing bacteria.

Answer 6

the root nodules in leguminous plants help the plants in getting moisture and nitrogen .example rhizobium

Answer 7

They help in nitrogen fixation, farmers frequently plant this leguminceae plants under rotation of crops and increase the soil fertility.

Answer 8

great question. : Nitrogen fixation. the process you are talking about.

This helps.. everything around. the plant, the soil, and in a chain it also helps life forms around. great natural way to fix nitrogen.. isn't ..no cost and specials involved..

Answer 9

nitrogen is used by plant to grow . fertilizer

Answer 10

Denitrifying bacteria.