Role of Soil Moisture in Fertilizer Use Efficiency for Rainfed Areas-A Review

Abstract

The balanced dose of fertilizer used for any crop to get the desirable yield is very much important in crop production and is dependent upon different factors like soil type, soil texture, soil structure, organic matter and especially soil moisture availability is the main and crucial factor in predicting optimum use of fertilizers. The areas where proper irrigation practices are available and the moisture level differences are minimum, there the prediction of fertilizer is simple and depends upon soil type, availability of different nutrients and organic matter in the soil which helps to estimate nutrient deficiencies to be supplemented by different fertilizers with optimum dose. Commendable job has been done by scientists of University of Agriculture, Faisalabad to design a model to predict fertilizer doses for all districts of Punjab for different cropping pattern with the help of some basic soil fertility status (organic matter, available phosphorus) assuming no water shortage during crop growth period.  Rainfed/barani tract comprises 3.10 million hectare (mha) out of total 11.83 mha under cultivation in Punjab. Therefore, the areas where irrigation practices are not present and the crop production is entirely dependent upon uncertain and uneven distribution of rainfall which makes the agriculture risky and the farmers are reluctant to incur expenditure on expensive inputs especially fertilizers, so one cannot rely only on basic soil fertility status. The fertilizer doses vary according to moisture available at the specific site besides other factors and one cannot use only soil type and nutrient levels for fertilizer dose prediction to get maximum and desired yields. In order to address this issue work done by different scientists is reviewed to establish the relationship or role of soil water contents in fertilizer use efficiency in rainfed areas to design a future study to predict different fertilizer doses under different prevailing soil water contents to achieve desired yield targets.