You have learnt from the lessons in the earlier Modules that soil properties influence soil health. These soil properties in turn are affected by the agricultural

You have learnt from the lessons in the earlier Modules that soil properties influence soil health.

These soil properties in turn are affected by the agricultural practices followed by a farmer.

Good agricultural practices not only help in managing the soil but also improve soil health.

What are these good agricultural practices?

Virtual Academy for the Semi Arid Tropics

Course on Soil and Soil Health

Module III: Soil Health Management

The good agricultural practices that help in improving and managing soil health focus on:

• Improving and maintaining organic matter in the soil;• Avoiding tillage practices that harm the soil structure;• Conserving the soil from erosion and other soil degrading effects;• Adopting integrated nutrient and pest management practices,• Rectifying soil problems like acidity and alkalinity.





Lesson 4: Integrated nutrient and pest management practices



After successful completion of this Lesson, you will be able to answer:

1. What is integrated nutrient management (INM)?

2. How INM helps in maintaining and improving soil health?

3. How INM is practiced?4. Explain with an example how INM helps

in maintaining and improving soil health?

5. What is integrated pest management (IPM)?

6. What IPM practices help in reducing the pest pressure in a cropped field?

7. How IPM helps in maintaining and improving soil health?





Improved and high yielding varieties of crops require application of fertilizers and controlling infesting pests to get the best benefit of growing such varieties.

But, continuous and imbalanced use of agro chemicals like pesticides and fertilizers affect the soil health by:

• adversely affecting the useful soil microorganisms, and

• the left over chemical residues become toxic to plants.





Hence, it is important to use these agro- chemicals very judiciously to get best yield without affecting the soil health.

Integrated nutrient management (INM) and Integrated pest management (IPM) are good practices to maintain the soil health without reducing the crop productivity.





Integrated nutrient management (INM) refers to use of organic manures and fertilizers in combination to maintain soil health and obtain best yields.

Sufficient and balanced application of organic manures and fertilizers is the focus in INM.





In integrated nutrient management (INM) approach, organic manures like farm yard manure, compost etc. are first considered for application. The balance crop nutrient requirements are supplemented with the appropriate fertilizer application.

Improved method of application along with proper timing of application are also considered to achieve the best efficiency of used organic manures and fertilizers.





Integrated nutrient management (INM) is practiced by applying the organic manures and fertilizers in combination after assessing what the soil can provide through soil testing, and the crop nutrient requirements to give certain amount of yield.

Let us consider an example for better understanding integrated nutrient management (INM) practice.





Step 1: Farmer expects an yield of 3 t (3000 kg) from one ha of sorghum.

Step 2: To get 1 t of yield, sorghum crop requires 20 kg N, 3.5 kg P, 30 kg of K, and small quantities of other nutrients.

So, to get 3 t sorghum yield, the crop requires

20 kg N x 3 = 60 kg N, 3.5 kg P x 3 = 10. 5 kg P and 30 kg K x 3 = 90 kg of K

(Nitrogen , phosphorus, and potassium are

expressed as N, P, and K)





Step 3: The soil test has shown that the soil

supplies 20 kg N, 3.5 kg P and adequate quantities of K and other nutrients.

Step 4: From Step 1, you know sorghum crop needs 60 kg N, 10.5 kg P and 90 kg K.

So, nutrients required from external source will be: 60 kg N – 20 kg N from soil = 40 kg N 10.5 kg P – 3.5 kg from soil = 7 kg P

As soil contains adequate quantities of K, there is no need to apply any K.





Step 5: Farmer has 3 cart loads (1500 kg) of FYM and 1 cart load (500 kg) of Compost to apply to the crop.

Step 6: 1500 kg FYM supplies: N = 1500 kg x 1% N = 15 kg N P = 1500 kg x 0.2% P = 3 kg P

Step 7: 500 kg of Compost supplies N = 500 kg x 2% N = 10 kg N P = 500 kg x 0.4% P = 2 kg P





Step 8: Application of FYM and Compost together supplies

N = 15 kg + 10 kg = 25 kg N P = 3 kg + 2 kg = 5 kg P

Step 9: A. Nutrients requirement from external source is 40 kg N and 7 kg P (see Step 4)

B. FYM and Compost application provides 25 kg N and 5 kg P (see Step 8)

C. So, the balance nutrient requirement is to be supplied through fertilizers. Balance N = 40 kg – 25 kg = 15 kg N Balance P = 7 kg – 5 kg = 2 kg P





Step 10: A. N fertilizer efficiency is 50%, so we

need to apply, 15 kg N x 2 = 30 kg N through nitrogenous fertilizer.

B. P fertilizer efficiency is 20%, so we need to apply, 2 kg P x 5 = 10 kg P through phosphatic fertilizer.

Step 11: Farmer has Urea and Super phosphate to apply to the crop.





Step 12: A. Amount of Urea (46% N) required to

supply 30 kg N is: 30 kg N x 46% N = 65. 21 kg or 65 kg

B. Amount of Super phosphate (16% P ) required to supply 10 kg P is: 10 kg P x 16% P = 62. 5 kg or 63 kg

Step 13: The farmer has to apply 3 cart loads of FYM, 1 cartload of Compost, 65 kg of Urea and 63 kg of Super phosphate to sorghum crop to harvest around 3000 kg of yield per ha.





This integrated nutrient management of applying 3 cart loads of FYM, 1 cartload of Compost, 65 kg of Urea and 63 kg of Super phosphate to sorghum crop, the farmer is benefited by:

•Better utilization of farm resources like FYM and compost;

•Application of FYM and Compost improves the soil organic matter;

•No excessive application of fertilizers;

•Soil nutrients are not exhausted by considering the efficiency of fertilizers;

•All the above factors help in maintaining the soil health and to achieve expected yields.





Integrated pest management (IPM) involves use of different crop pest control practices like cultural, biological and chemical methods in a combined and compatible way to suppress pest infestations.

The main goal of IPM is to manage pests and the environment so as to balance costs, benefits, public health, and environmental quality.

A number of non-chemical cultural practices form the core of IPM. But IPM does not do away with chemical pesticide usage.





IPM is not new to our farmers’ community.

•Summer and post harvest ploughing has been in practice with the farmers to expose soil insects and pupae.

•Growing of marigold plants in commercial crops like chillies and vegetables have been practiced by many farmers.

•Use of neem twigs while storing grain also practiced by our forefathers.

Such practices not only minimize the expenditure on pesticides and their application but also help in maintaining the biological balance in nature.





The major tools for the development and adoption of IPM strategies are pest surveys and monitoring.

• A field crop is monitored to determine a pest economic status or to determine whether a natural enemy is at a level capable of suppressing a pest's population density. So identification of pests and beneficial insects is of prime importance before any control operation is executed.





The major tools for the development and adoption of IPM strategies are pest surveys and monitoring.

• Monitoring tools like pheromone, light and sticky traps can be advantageously used.

• Field scouting adopting fixed plot survey or roving survey should be taken from time to time to monitor the crop in determining whether the pest population is leading to severe damage of the crop.





Some IPM practices:

• Use of monitoring tools like pheromone traps, light traps, colored sticky traps.

• Bird perches.

• Use of seed dressing bio- and chemical pesticides

• Adoption of resistant varieties.





Some IPM practices:

• Use of eco-friendly insecticides like neem products and bio-fungicides like Trichoderma sp.

• Considering natural enemies like Trichogramma egg cards, and microbial preparations like NPV etc.

• Use of bait preparations.





Some IPM practices:

Insect traps Colored sticky trap





Some IPM practices:

Bird perch Cattle egrets eating caterpillars





Several effective IPM practices that are cost effective, sustainable and eco-friendly in different ecosystems have been developed for various crops.

For more information on IPM, please visit the following Internet sites:

http://agri.and.nic.in/biocontrol..htmhttp://www.vigyanprasar.com/comcom/develop51.htm http://www.vasat.org/learning/agri/chickpea_htm/insect_pests/ipm.htmhttp://www.ncipm.org.in/ipm.htmhttp://www.ikisan.com/links/pnj_pests.shtml#Integrated%20Pest%20Management

http://agri.and.nic.in/biocontrol..htm

This concludes the Lesson 4: Integrated nutrient and pest management practices - in this Module.

Problem soils and their reclamation procedures are discussed in the last Lesson in this Module.

Select Lesson 5 from Module III contents




Documents

You have learnt from the lessons in the earlier Modules that soil properties influence soil health. These soil properties in turn are affected by the agricultural