The Availability Of Iron In Soil And Plants Treated With Organic And Inorganic Fertilizers In The Jordan Valley

Abstract

This paper deals with the rcults of a study carried out on "Phoseolus vulgaris - Wed" as an indicator of chlorosis. The study took place between July 1990 and July 1992, and for two crop seasons each year. Six kinds of fertilizer were used. Soxtrinc (Iron), granular superphosphate, liquid phosphate fertilizers, and natural fertilizers: manure and quarters waste of sheep, cows and egg-laying hens. An area of about three-quarters of an acre in Jericho (Jordan Valley) was used for the study, using the same means, methods, materials and chemical fertilizers which are available to farmers in that area. The study confirms what is well known to the farmers that direct "Foliar Spraying" is the most efficient method in treating chlorosis, followed by the methods of using natural fertilizers. The study illustrates the rate of chlorosis as follows: Control > Granular Superphosphate > Liquid Phosphate Fertilizer > Cow's manure > Hen's manure > Soxtrine (Iron). In addition, the study confirms that chlorosis is not attributable to iron deficiency in the soil, but rather to its lack of availability. The main factors which play a role in determining the availability of iron arc: nature of soil, kind of plant, pH, rate of ion exchange, antagonism, syncrgism, and fixation as well as the leaching factor, all of which are related to weather elements like rain, humidity, ventilation and temperature.