The Journal of Research ANGRAU

J.Res. ANGRAU 36(1) 36 - 41, 2008
FERTILITY STATUS OF SOILS IN VIZIANAGARAM DISTRICT
P. JAMUNA, Y. NOOKA RAJU and K. RAMALINGA SWAMY
Regional Agricultural Research Station,
Acharya N.G. Ranga Agricultural University,
Anakapalle - 531 001
ABSTRACT
Representative soil samples were collected from different farmers’ fields in nine mandals of
Vizianagaram district and assessed for their nutrient status. Majority of soils in the district are red sandy loams
and few are of clay loams. Mostly ground nut and mesta are cultivated under dry land and paddy under wet
land situation. The soils ranged from acidic to neutral in reaction and normal in conductivity. Soil available
nitrogen (N) was found to be low in majority of the samples in all the mandals. The district on an average had
61.1% of the soil samples in the low category. Soil available phosphorus (P 2
O 5
) varied wide from very low of
2.5kg/ha to as high as 178.2kg/ha, indicating non or over adoption of P fertilizers. Soil available potassium
content (K 2
O) was high in majority of samples in all the mandals except in Garividi mandal which on an average
had 82.7% of the soil samples in the high category.
The process of assessing the level of nutrients in the soil in a form that is available
to crops is known as ‘Soil testing’. It is a pre-requisite to know the nutrient content in the soil
and apply required amount of nutrients to correct imbalances and optimize crop nutrition.
Balanced fertilization does not mean a certain proportion of N, P and K or other
nutrients to be added in the form of fertilizers, but it takes into account the availability of
nutrients already present in the soil, crop requirement and other factors. It should take into
account the crop removal of nutrients, the economics of fertilizer use, farmers’ investment
ability, agro-techniques, soil moisture regime, soil salinity, alkalinity, physical environment,
microbiological condition of soil and cropping sequences etc. (Subba Rao and Sanjay
Srivastava, 2001).
Soil testing is not static, but a dynamic concept. It does not mean that every time a
crop is grown, all the nutrients should be applied in a particular proportion, rather fertilizer
application should be tailored to the crop needs, keeping in view the capacity of soils (Won
vexkule and Mutert, 1992). It was further elaborated by Tandon and Kinno (1993) that balanced
fertilizer use or rather balanced crop nutrition ensures an optimum supply of all essential
nutrients. It promotes synergetic interactions and keeps antagonistic interactions out of crop
production system. It discourages lopsided applications of any nutrient or over fertilization.
In view of the importance of soil tsting, the samples collected from farmers fields
during ‘Rythu Chaitanya yatra’ in pre-kharif season of May 2005 in Vizianagaram district
were analysed for giving agro-advisories based upon the soil testing results.
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