Biostimulants Help Grain Crops Withstand Stress

Over millennia, rice, wheat, barley, and maize – the major grasses we rely on for food – have developed processes to help withstand the pressures or stresses that may threaten their productivity or survival. Understanding the stimuli that cause these processes, and even help the grasses’ defense mechanisms, is essential.  

Giving a Bio Boost to Crops

Biostimulants can contain substances or microorganisms that enhance the natural processes of plants to tolerate stress, uptake and use nutrients, as well as ensure good growth and quality. Biostimulants and biofertilizers are increasingly used in a wide range of crops including vegetables and fruits, as well as the major food crop grasses.  

Seaweed Solution to Stress Resistance

Among various biostimulants, the common cold-water seaweed Ascophyllum nodosum is recognized for its ability to promote plant growth and development at germination and increase resistance to biotic or abiotic stresses. This seaweed in naturally rich in many nutrients and beneficial enzymes. These substances are all easily extracted from the seaweed. The extract is highly versatile and can be used as a seed treatment, foliar spray, drench, or in fertigation. The response of crops to applications of this biostimulant is clear and sustained: better growth, increased nutrient absorption, stimulated antioxidant system, activation of defense mechanisms, and greater resilience to stress whether that be from water shortage, excess heat, or salinity.  

Positive Effects of Seaweed Treatment to Seeds, Roots and Shoots

Using A. nodosum in seed treatment has been shown to improve germination velocity, embryonic development and maintain seedling vigor. Maize plants that were treated with A. nodosum showed greater root length and volume, especially secondary roots (Figure 1), which are responsible for absorbing water and nutrients.  

Figure 1. Roots from maize plants grown with the biostimulant Bioz Sunstone (right) showed greater root length and volume than the control plants (left).

  There are several measurable benefits in the crops. Nutrient concentration was evaluated in maize plants treated with A. nodosum extract and it was found that the levels of elements such as calcium, magnesium, sulfur, and molybdenum increased sharply after the extract was applied when compared to the control treatment. Application of A. nodosum increases not only the quality of the harvested product but also the shelf life. These benefits can be attributed to the way that algae extract induces changes in physiology, mainly related to the secondary metabolism of plants, which improves shelf life. Another way of putting it is that A. nodosum slows the degradation process and maintains the integrity and turgor of cells.  

Stress-busting Benefits of Biostimulants

Wherever in the world major food crops are grown, it is likely they will have to endure one or more stress factors during their life cycle. Some have to cope with several at once. The main stresses that plants are subject to are water deficit, excess light, high temperatures and, in some instances, salinity caused by fertigation practices. There can also be pest and disease attacks. In response to these stresses, plants carry out physiological, biochemical, and morphological changes. The best part being that the application of the biostimulant A. nodosum alleviates the effects of these stresses, or helps the crop to cope with them. This happens because the constituents of this seaweed extract have been found by researchers to contribute to plants’ natural coping mechanisms. These include increased hormonal modulation, osmotic control, improvement in nutrient absorption efficiency and use, nitrogen and sulfur metabolism, effects of antioxidant system on secondary metabolism, changes in structure, and enlargement of the root system, among others. With all these benefits to gain from, there are numerous seaweed or algae extracts available with different application methods and intentions. According to recent studies of A. nodosum products, Bioz Sunstone technology offers the best response in the field in seed treatment for grasses, especially for maize, wheat, and rice crops.  

Bioz Sunstone Technology in Action

When tested, in addition to giving better seed coating and excellent compatibility with beneficial microorganisms, Bioz Sunstone offers a balance between physiological and nutritional effects all in one product by:

• enhancing the expression of seed vigor, promoting greater uniformity in the initial development of plants.
• promoting greater development of the root system, with penetration and exploitation of a greater volume of soil.
• creating deep and branched root system promoting greater physiological balance and increasing tolerance to water deficit, especially when it comes to crops planted in a rainfed system (Figure 2).

Figure 2. After 12 days without rain, the benefits of the deeper branched root system of maize grown with Improver Max biofertilizer (right) are clear.

  In rice, the multiple benefits of Bioz Sunstone technology have been carefully measured. Enhanced area and length of roots (up 18%) and shoots (up 16%) contributed to overall increase in the harvest of rice from irrigated plots (up 24%) compared with control plots as shown in Figure 3.  

Figure 3. Bioz Sunstone enhances irrigated rice roots (up 18%) and shoots (up 16%) compared with control plots.

  In wheat studies, there was a dramatically visible difference between the seedling shoots and roots from seed treated with Bioz Sunstone technology (see Figure 4). Root development was up 123% and eventual productivity from the crop was increased by 180 kg/ha.  

Figure 4. Bioz Sunstone increased length of wheat shoots (up 11%) and roots (up 123%) compared with control plots.

  Measuring the difference made from incorporating Ascophyllum nodosum seaweed extract into the nutrient management strategy for key crops such as wheat, rice, and maize is helping farmers to harness the maximum potential from the seed they sow by using Bioz Sunstone technology. The stress of knowing what harvest a farmer will get, especially when factors beyond the grower’s control take effect, such as challenging weather, is eased by the knowledge that we now have a way to help key crops cope with the stresses heaped upon them and grow healthily and productively whatever happens.