7 tips for a gold standard salinity and sodicity management program

Salinity and sodicity could be affecting your crops without you even knowing! Between 25 – 35% of worldwide agricultural lands are affected by these two abiotic stresses, which are also probably the two most difficult to manage.

However, there are 7 tips that can help you counteract the negative effects of salinity and sodicity. Continue reading to learn how to develop this gold standard program!

1. Start with the soil

Often overlooked in salinity and sodicity management, early application to soil of Humic Acid products like Humifirst / Humistar or Turbo Root should be one of the key foundations of any salinity and sodicity management program. Salinity and sodicity reduce root biomass, and with less roots the crop has less surface area to absorb water and nutrients.

Humic Acids increase root growth and absorption selectivity while also helping improve Sodium tolerance.

Tradecorp’s research with Italian Research Centre, Landlab, has demonstrated the astonishing effect of Humistar / Humifirst on root growth rate and biomass as shown in this time-lapse video.

2. Counteract the Potassium uptake problem

Salinity and sodicity reduce Potassium uptake from the soil and this often creates Potassium – Sodium imbalances in the crop tissue. As the crop is already facing difficulties in absorbing sufficient water, and nutrients, from the salty soil solution regardless of the quantity of nutrients in the soil, applications of high quality foliar Potassium, such as Final K or Amifol K, bypass these problems and help ensure the crop is adequately nourished with Potassium.

3. Boost the energy of the crop

Crops have some ability to excrete excess salinity and sodicity both directly and indirectly… but this takes a lot of energy and can result in crop energy deficits that reduce growth and eventually yield.

The foliar application of Amino Acid products from the Delfan and Aton families help give crops a boost in energy which enables increased production of proteins related to abiotic stress management. This helps the crop maintain growth while also reducing the tendency to abort flowers and fruit as the crop tries to save energy, which as growers know, is a very common problem in saline and sodic soils.

4. Prevent the effects of abiotic stress with Primactive products

Biostimulants with a Primactive effect prepare or “prime” crops to increase their tolerance to abiotic stress. However, correct timing of biostimulant application is critical to ensure maximum effect. This is particularly important in the case of biostimulants with Primactive effect.

As salinity and sodicity are “permanent” stresses, there is no start or finish to the stress, making prevention or priming type application a bit different. Tradecorp recommends applying products with Primactive effect, such as Phylgreen, by fractionation, spray little and often to the crop, where cases of salinity and sodicity are suspected or known. In these situations the objective is to help reduce the abiotic stress effect across the entire crop cycle.

Fractionation type application will not only help the crop better resist abiotic stress along the cycle via the Primactive effect, but also provides key compounds such as mannitol. These natural compounds are called “compatible osmolytes” and help reduce the damage to plant cells and genetic structure that results from salinity and sodicity induced drought stress caused by decreased water absorption as mentioned above.

5. Reduce salinity and sodicity in the root zone

Active management of salinity and sodicity in the root zone can help increase profitability without incurring the cost of treating the whole soil area. Solutions specifically designed to tackle the saline root zone, Saltrad for example, are effective solutions that enable farmers to continue profitable production.

Saltrad has been designed to tackle salinity and sodicity through multiple modes of action in the soil. For example, the Organic Acids contained in Saltrad preferentially lift Sodium from the soil surface resuspending it back into the soil solution – in effect washing the surface of the soil free from Sodium. The washed soil surface is then covered and protected with highly soluble Calcium that is present in Saltrad helping to restore the natural soil structure and this improves growers ability to wash or leach the Sodium down below the root zone by leaching irrigations or during heavy rainfall.

6. Leach soluble salts below the root zone

Did you know that 1 megalitre of water that is saline to 1ds /m (640 mg / kg or 640 ppm) contains 640 kg of salts and these will be deposited on the land during the irrigation?

Irrigation water, although key for crops, often brings the unwanted side effect of naturally dissolved salts, particularly Sodium and Chloides, and this is why salinity and salinity can appear quickly in soils under irrigation.

And did you know that in addition to salts, irrigation water usually contains dissolved bicarbonates and that these bicarbonates solubilise Calcium from the surface of soil particles?

These bicarbonates increase leaching of Calcium down below the root zone with the position in the soil previously occupied by the Calcium now replaced with the Sodium in the irrigation water.

These combined processes accelerate the build-up of salinity and sodicity!

With this in mind, the elimination of Bicarbonates from irrigation water, with products like Lower 7, is key to reducing Calcium leaching and helps to slow down the build-up of salinity and sodicity in soils.

7. Back to basics – don´t forget your micronutrients

When managing salinity and sodicity it is easy to forget the basics. In addition to reducing macronutrient uptake such as Potassium and Phosphorus, salinity and sodicity reduce the uptake of most micronutrients, making it very common for crops to suffer from the “hidden” hunger of micronutrient deficiency.

Soil tests will often show adequate reserves of micronutrients but under the stressful growing conditions of salinity and sodicity, micronutrient absorption is reduced, which increases the chance of sub-optimal yield and quality and thus reduced profitability.

Avoid the risk of hidden hunger using Tradecorp´s EDTA/EDDHA Chelates. EDTA / EDDHA chelates are recognised as the most effective micronutrient type for use in soils and help ensure sufficient uptake of the nutrient by plants and they are also ideal for foliar application due to their excellent tank-mixing properties.

The benefits of the 7 tips outlined above in salinity and sodicity management are cumulative, combing most, or all, will give maximum benefit and profitability.

References:

1. Khaleda, L. P. (2017). Humic Acid Confers HIGH-AFFINITY K+ TRANSPORTER 1-Mediated Salinity Stress Tolerance in Arabidopsis. Molecules and Cells, 40, 966-975.

doi: doi.org/10.14348%2Fmolcells.2017.0229

2. Merwad, A. (2017). Effect of humic and fulvic substances and Moringa leaf extract on Sudan grass plants grown under saline conditions. Canadian Journal of Soil Science, 97, 703 – 716.

doi: doi.org/10.1139/cjss-2017-0050

3. DPI NSW. (2014). Farm water quality and treatment. Sydney: Department of Primary Industries, New South Wales State Government.

4. Gangloff, W. W. (2006). Relative availability coefficients of organic and inorganic Zn fertilizers. Journal of Plant Nutrition, 25, 259 – 273

doi: doi.org/10.1081/PLN-100108834

*Amifol K,delfan,Humifirst,Lower 7,Phylgreen,Primactive,Salinity,Sodicity,starter,Turbo Root