Nutrient management

 

 

 

 

 

Nutrient management for rainfed rice environments

 

 

 

 

 

 

Describe nutrient management practices for the different rainfed rice environments

 

 

 

 

 

 

 

 

Introduction

 

Rainfed environments are more often affected by abiotic stresses like drought, submergence, or salinity than irrigated rice-based systems. This increased risk is often referred to as the main reason for the low fertilizer use in rainfed ecosystems. Also, it is commonly believed that traditional varieties, which are still used in many rainfed systems, do not respond to fertilizer applications.

 

Both these arguments are simplifications. Proper nutrient management can help to increase yields and productivity in rainfed ecosystems. Adjusted nutrient management can even contribute to reduce the negative effects of abiotic stresses!

 

In this lesson, we give some general guidelines and some  specific guidelines for nutrient management of rainfed rice under abiotic stresses:

 

 

 

What should you always do in the rainfed rice system?

 

 

 

 

 

General guidelines for nutrient management in rainfed rice

 

1. Use improved varieties

If available, choose a variety that is more tolerant or resistant to certain stresses. (Drought tolerant, submergence resistant,...) For some stresses, try to use improved varieties with stress avoidance mechanisms (e.g., shorter duration varieties). It is important to have the right variety in order to have the right crop response to nutrients.

 

Choose for example a variety that can grow taller in case of floods

 

2. Good nursery management

A good nursery produces strong seedlings that can deal better with abiotic stresses.

Phosphorus (P) and nitrogen (N) are necessary nutrients. But too much N produces weak stems that are easily damaged during transplanting. Zinc (Zn) is very  important in alkali/sodic soils with a basic soil reaction (pH >8).

 

 

Click here for fertilizer application rates.

 

Fertilizer application in the seedbed is cheap and effective, and is therefore highly recommended in transplanted rainfed rice.

 

 

3. Use organic fertilizer  

Using organic materials is much more important in rainfed systems than in irrigated systems. Often, the soils  in rainfed systems have micro nutrient shortages. Applying organic fertilizer is very helpful to increase the amount of micro-nutrients in the soil. Also, organic residues like straw improve the water holding capacity of especially sandy soils (important in drought-prone fields) and ameliorate alkali/sodic soils.

Click here to learn what to apply and how to apply it.

 

If there is only limited use of inorganic fertilizer more necessary nutrients must come from application of organic materials. Crop residues like straw (left) or animal manure (right) can be used as organic fertilizer.

 

 

 

 

 

 

 

 

 

 

How should you apply nutrients if you have to deal with the following abiotic stresses?

 

 

Please click on the different pictures!

 

If you work in favorable rainfed lowlands,meaning that your system suffers very little from abiotic stresses, then you should apply the nutrient management for irrigated rice systems (see earlier lessons).

 

 

 

 

 

 

Next lesson

 

Test you knowledge of this module in the quiz.