Nitrogen deficiency 157885 220478002 2008-06-20T01:37:47Z Earthdirt 3512837 fix pix cap [[Image:Spitskool stikstofgebrek (nitrogen deficiency) Brassica oleracea convar. capitata var. alba.jpg|right|thumb|275px|A young cabbage plant exhibiting nitrogen deficiency.]] :''This is about nitrogen compounds in plant nutrition. For shortage of nitrogen compounds in human and animal nutrition, see [[protein deficiency]].''<br> '''[[Nitrogen]] (N) deficiency''' in [[plant]]s can occur when woody material such as [[sawdust]] is added to the [[soil]]. Soil organisms will utilise any nitrogen in order to break this down, thus making it temporarily unavailable to growing plants. '[[Nitrogen robbery]]' is more likely on light soils and those low in organic matter content, although all soils are susceptible. Cold weather, especially early in the season, can also cause a temporary shortage. All vegetables apart from [[Nitrogen fixation|nitrogen fixing]] [[legume]]s are prone to this disorder. Symptoms include poor plant growth, leaves are pale green or yellow in the case of [[brassica]]s. Lower leaves show symptoms first. Leaves in this state are said to be [[etiolation|etiolated]] with reduced [[chlorophyll]]. Flowering and fruiting may be delayed. Prevention and control of nitrogen deficiency can be achieved in the short term by using grass mowings as a [[mulch]], or [[foliar feed]]ing with [[manure]], and in the longer term by building up levels of organic matter in the soil. Sowing [[green manure]] crops such as [[rye|grazing rye]] to cover soil over the winter will help to prevent nitrogen leaching, while leguminous green manures such as [[winter tares]] will fix additional nitrogen from the atmosphere. {{PlantMineralDeficiency}} {{plant-disease-stub}} [[Category:Physiological plant disorders]] [[Category:Nitrogen metabolism]]