Dryland Agriculture

Introduction

Climate change is becoming increasingly threatening. Groundwater scarcity, species extinction and prolonged droughts are leading to global consequences. In view of the increasingly difficult conditions for food production and the rapidly growing world population, solutions are needed to get these problems under control.
Agriculture is one of the sectors that will be the hardest hit by climate change, especially smallholder farmers. Dryland farming is about making positive contributions to these problems.

What Is Dryland Farming

Dry farming uses special agricultural techniques for the non-irrigated cultivation of crops and is used in low rainfall areas around the world. Agriculture in drought prone areas with scarce water resources can be challenging, but issues can be tackled with dry farming methods. Dry farming is dependent on natural rainfall and is used by farmers to continually adapt to the presence or lack of moisture in a given crop cycle.

Types of Dryland Agriculture

Dryland Agriculture refers to farming entirely dependant on rain conditions and without secure irrigation facilities. Dry farming is divided into three categories based on the amount of rainfall received:

• Dry Farming: Cultivation of plants in areas with less than 750 mm of rainfall per year
• Dryland Farming: Cultivation of crops in areas with rainfall exceeding 750 mm per year
• Rain Fed Farming: Cultivation of crops in regions with rainfall above 1,150 mm per year

Key Elements And Challenges Of Dry Farming

The key elements used to combat the perils of dryland agriculture are capturing and conservation of moisture, the effective use of the available moisture, as well as soil conservation and the control of input costs. On the other hand, there are also some challenges for dry farming in India. These include moisture stress and uncertain rainfall, effective storage of rainwater and the selection of limited crops. Furthermore, proper disposal or dry farming products and the quality of the produce can be an issue.

Dryland Farming Techniques

There are agricultural techniques and measures developed specifically for farming under dry conditions. In order to improve agricultural production in dry areas, the following points should be taken into account.

Start preparation and sowing work in good time, including measures to maintain stored soil moisture.

Try using improved plant varieties that can withstand moisture stress. For soil moisture conservation, deep tillage, surface tillage and stubble use should be performed to optimize water movement and soil water penetration.

With an eye to the sensible use of rainfall, surface water and groundwater, proper watershed management can not only halt further deterioration of the ecosystem but also restore damaged soils.

To increase the yields of crops, cultural practices like mix cropping, inter cropping and crop rotation should be followed. Get more information about matching plants for mix cropping from our #PlantiXperts in Plantix Community.

IPM (Integrated pest Management) techniques should be adopted to create unfavourable conditions for pests and weeds.

In terms of effective utilisation of water, it is recommended to use drip irrigation systems as well as practicing lining of canals.

To develop these methods, non-farm operation dryland areas should be supplemented by other non-farm occupations such as animal husbandry, fisheries, poultry and social forestry.

Crops

From cereal grains to grain legumes to leafy vegetables, a variety of arable crops can be cultivated under dryland conditions. Also, root crops and some fruit vegetables are quite suitable for dryland farming.
In view of the fact that about 84 districts in India are rain areas, 42% of the food grain, 75% of the oilseeds, 90% of the di-cot grams, sorghum and peanuts, as well as 70% of cotton and more than 60% of the rice fields of the total Indian agricultural production originate from dry and rain fed farming. Thus, Dryland agriculture occupies nearly 75% of India's cultivated area and produces 44% of food requirements. This means it will continue to play a critical role in India's food security, both now and in the future.

Four Dryland Techniques To Reduce Evaporation

1. Mulches:

Up to 75% of the rainfall is lost through evaporation. Those losses can be reduced by applying several kinds of mulches. Mulching refers to the various materials that are applied to the soil surface to reduce evaporation and improve soil water. Applying mulchs leads to additional benefits like soil conservation, moderation of temperature, reduction in soil salinity as well as weed control and general improvement of soil structure.
There are a few types of mulches that can be used for a variety of environmental conditions. If the soil surface is loosened, it acts as soil or dust mulch to reduce evaporation. For example, soil mulch can be created through intercropping.

Left on the soil surface, plant remnants, such as cotton stems, can be used as a stubble mulch. In addition to reducing evaporation losses, stubble mulching also protects the soil from erosion. Also, straws can be used as a mulch. However, mulching with plant remnants is always a compromise. Although it protects against soil erosion and helps to keep moisture in the soil, plant residues can also contain pathogens that can infect your crops.

Plastic materials such as polyethylene or polyvinyl chloride are great for mulching vegetables and bush crops. Plastic mulch is available in three basic types: black, clear and white on black. Plastic mulches have a good water holding capacity and effectively inhibit weed growth. Furthermore, they have the ability to greatly maintain fertiliser levels.

2. Antitranspirants

A favourable water balance can be maintained by the control of crop transpiration. An Antitranspirant is any material applied to transpiring plant surfaces. There are four different types.

Fungicides like phenyl mercuric acetate (PMA) in low concentration are used as antitranspirants by inducing stomatal closing. Stomatal closing can, however, decrease photosynthesis.

Wax-like materials, which form a thin film on the surface of the leaf, inhibit the escape of water by forming a physical barrier. Mobileaf, hexadecanol or silicone are some of these film-forming antiperspirants. However, these chemicals are only recommended to a limited extent because they also reduce photosynthesis.

Additionally, there are also some reflectant type chemicals like 5% kaolin spray. By reflecting the radiation these antitranspirants reduce leaf temperatures and thus also reduce transpiration. Another type are growth retardants such as cycocel. Due to the reduction of shoot growth and the support of root growth, cycocel enables the crop to resist drought.

In general, the use of antitranspirants should be limited to saving the crop from failure under severe moisture stress. They are also beneficial for reducing the transplantation shock of nursery plants. Thus, they have some practical use in nurseries and horticultural crops.

3. Wind Breaks and Shelterbelts

Wind breaks are all buildings or structures that obstruct the flow of wind and reduce wind speed. Shelter belts are rows of trees planted to protect plants from the wind. Due to reduction in wind speed, evaporation losses are reduced and more water is available for plants. Additionally, shelterbelts reduce wind erosion.

4. Weed Control

Since weeds compete with crops for limited soil moisture, regularly weeding is the most useful measure to reduce transpiration losses. Thus, it is recommended that weed control be carried out in a timely and regular manner to eliminate this competition and to provide crops the maximum level of available moisture.

In case of revival of rain and the relief of moisture stress, a nutritive solution spray is recommended. P.e. urea or DAP spray (2% solution) is useful for faster regeneration of crops after rain.