Speciality fertilizers in agriculture: An overview Dr. Hugo Opperman - - PowerPoint PPT Presentation
Speciality fertilizers in agriculture: An overview Dr. Hugo Opperman Head chemist MBFi FERTASA Congress 19 APRIL 2018 Biggest problem the world is facing today is food security Reasons for the crisis? Decreasing agricultural land and
Speciality fertilizers in agriculture: An overview
Head chemist MBFi FERTASA Congress 19 APRIL 2018
Biggest problem the world is facing today is food security
Reasons for the crisis? Decreasing agricultural land and increasing world population Erosion Desertification Poor soil management Poor water quality Pollution FAO study reports 2 billion hectares lost since 1950’s By 2050 there will be 9 billion mouths to feed (FAO, 2010)
Only 12 % of the surface area of South Africa has the potential for efficient crop production. Most
cultivatable land. SA population expected to grow 2 % annually and reach 82 million by 2035.
0,2 0,4 0,6 0,8 1961 1970 1980 1990 2000 2007 2017 2027 Ha per capita Year
1000 3000 5000 7000 9000 11000 13000 15000 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014
YEAR
SA Maize production
Crop production (1000 Ton) Area planted (1000 Ha) Consumption (1000 Ton)
Traditional Increasingly
Nutrition Soil biology Structural
Plant physiology Nutrition
Definition: ‘Fertilizer’ can be defined as any substance, natural or chemical, that is added to the soil or directly to plants to improve fertility or enhance plant growth and health. Better soil and plant fertility practices = Smarter speciality fertilizer
Speciality fertilizers provide tools in your toolbox to improve/manipulate various plant growth factors Can be overwhelming and feel more like a black box
Specialty fertilizers are applied to soil, seed and plants to improve the crop’s physiological processes – its growth, blooming and maturity period. Speciality fertilizer is a fast growing market, with an estimated growth rate
market is estimated to reach 24 billion USD by 2022.
Speciality fertilizers 3 main classes
Nutrients Biostimulants Biologicals
release fertilizers
Very versatile can either be applied via seed treatment, pre-plant, with planting fertilizer or as foliar fertilizer
Micronutrients are often overlooked and can limit crop production significantly
88 % of soils in Sub-Saharan Africa is deficient in zinc 73 % of soils in South Africa is deficient in boron
Foliarly applied Seed treatments With planting fertilizer Applied to soil: Pre-plant
Special considerations
Most micronutrients with the exception of boron and molybdenum are in a cationic form – divalent transition metals M2+ Highly reactive to anions such as phosphates and sensitive to changes in pH Must be in water soluble (ionic) form for plant uptake Can also react with other compounds such as herbicides in tank mixture
Many types of chelation molecules have been developed Synthetic chelates – EDTA, DTPA, EDDHA etc. Organic chelates – Organic acids such as amino acids, fulvic acid, citrates, carbohydrates Binds to metal (M) ion and protects it from reacting
The foliar uptake of nutrients is one important part, but the aspect which is even more critical is the ability of the nutrients to be translocated to other plants cells and organs once taken up. Chelates bulky molecules - decrease absorption and translocation of the nutrient Excellent chelating agents - high absorption and translocation characteristics Should be comparable with inorganic salt nutrients
Supply young seedling with micronutrients for its early growth period - roots are still developing. Micronutrients are immobile in most soils - early season deficiencies. This has been shown to result in stronger seedlings which can translate into higher yields. A polymer in often added - adhesion onto the seed Colorant for identification of treated seeds.
Most bulk blenders in South Africa add micronutrients to a blend in the form of micronutrient Granules.
Blended micronutrients Coated micronutrients
Leads to uneven spatial distribution Even spatial distribution Micronutrients immobile soil
10 20 30 40 Bothaville Delmas Lichtenburg Bethlehem LEAF ZINC CONCENTRATION (PPM) Trial location No zinc Granular zinc sulphate Coated zinc
Zinc leaf analysis of maize at 4 different trial locations (2016/2017 season). Treatments differed only in zinc type. No zinc, granular zinc sulphate and coated zinc. The same zinc equivalent was used for the zinc sulphate and coated zinc treatments per hectare.
2000 4000 6000 8000 10000 Bothaville Delmas Lichtenburg Bethlehem MAIZE YIELD IN KIOGRAM PER HECTARE TRIAL LOCATION No zinc Granular zinc sulphate Coated zinc
Average maize yields of the four trial locations for the different zinc treatments (2016/2017 season). Five statistical plots were planted for each treatment at each location.
Main goal of modified fertilizers are to enhance the nutrient use efficiency of the fertilizer Nitrogen cycle
Urea Ammonium Urease Nitrites (NO2
Nitrates (NO3
Nitrosomonas Nitrobacter Ammonia (volatile gas) Leaching
Inhibitors - chemical action Urease inhibitors inhibit urea to ammonium Nitrification inhibitors inhibit ammonium to nitrites and nitrates. Inhibition lasts between 14 and 28 days. Controlled/slow release fertilizer - physical barrier Usually polymer coating. Release nutrients under very specific conditions – temperature, humidity, soil water level etc. Provides a sustained nutrient release.
Definition: Biostimulants are defined as any substance or microorganism applied to seeds, plants or the soil with the aim to enhance nutrition efficiency, abiotic stress tolerance and/or crop quality traits, regardless of its nutrients content. Global market value of almost 2 billion USD in 2018.
Seaweed extracts Synthetic plant hormones Organic compounds Inorganic compounds
Contains complex carbohydrates, plant hormones (cytokinins and auxins), macro- and micronutrients, betaines and sterols. Can be applied on soils, in hydroponic solutions as seed or foliar treatments. Growth stimulating effect High amounts of antioxidants which is effective in plant stress relief.
The effect of seaweed treatment (left) and untreated (right) on root development.
The use of synthetic plant hormones (also produced naturally in the plant) has also been shown to be very effective in stimulating plant growth and crop quality traits. There are 5 major classes of plant hormones and each of them are involved in controlling specific metabolic processes.
Auxins – IAA, NAA, IBA Cytokine – Kinetin, Zeatin, 6-BAP Gibberellins – GA3, GA7 Abscisic acid
Ethylene – Ethylene releasing compounds
Hormones levels fluctuate with phenological stages. Each hormone type causes specific metabolic response. Hormones work in synergy with plant specific plant nutrients at the specific growth stages.
Adapted from Stoller USA.
2834 2690 2761 3136 3150 3285 2014/2015 2015/2016 2016/2017 SOYA YIELD IN KIOGRAM PER HECTARE Trial year
Soya trials Bethal X-press Fuctional at sprayed V6
Control X-press functional 3130 3080 3190 3546 3600 3310 2014/2015 2015/2016 2016/2017 SOYA YIELD IN KIOGRAM PER HECTARE Trial year
Soya trials Delmas X-Press MoB sprayed V4 and R1
Control X-press MoB
The effect of two different hormone products containing complimentary nutrients on the average soya crop yield over 3 trial years. The control treatments only contained nutrients without the hormone compounds. Five replicates were done per treatment.
Humic acid Fulvic acid Amino acid
Vast amount of organic compound have been identified and are being used for their biostimulant properties. Only the most commonly used examples will be discussed in this presentation. Humic and fulvic acid compounds – Improve soil structure, improve nutrient uptake, protects against stress conditions Amino acids – improves nutrient uptake, increase stress tolerance, increases plant energy Salicylates – increases plant stress tolerance
4475 2232 5153 2585 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 Wheat Canola YIELD IN KIOGRAM PER HECTARE CROP TYPE
Riversdal trials Aminex at 2L/Ha - 2016/2017
Untreated control Aminex
The effect of an amino acid spray treatment on the yield response of wheat and canola in the Riversdal area. Application of the product was 2L/Ha. Wheat was sprayed at flag leaf stage, whilst canola was sprayed at the end of flowering.
Phosphites – Increased root development Increased disease resistance Improves fruit yield and quality Silicon - Increases stomatal regulation – increased salt and drought tolerance Regulates antioxidant system – increased stress tolerance Protects the plant against heavy metal stress
Biological fertilizers/stimulants can be of bacterial or fungal origins. Most products available in the market are either applied directly to the soil or as seed treatments. They improve plant growth by improving nutrient availability and uptake (biofertilization), producing compounds that stimulate growth and disease resistance (biostimulants), control of pathogenic organisms and pests as well as improving soil structure.
Beneficial bacteria
The most widely used biological organism in agriculture is nitrogen fixing rhizobium bacteria These bacteria are widely applied as seed treatment or in furrow to help nodulation in legume crops. Eg. Bradyrhizobium japonicum
Another example of beneficial bacteria is members of the genus Bacillus. They are termed plant growth-promoting rhizobacteria (PGPR) and are capable of effectively colonizing plant roots Bacillus advantages
natural cytokinins and auxins – promotes plant growth
plant nutrients, especially bound phosphates
plant defences
Bacillus subtilis (green) biofilms on an Arabidopsis root surface. Credit: University
The most common beneficial fungi used in agriculture is Trichoderma. Forms a physical bond with the root system of its host plant and establish itself in the rhizosphere.
production of enzymes such as cellulose and xylanase
Trichoderma advantages
4668 5152 5292 5813
Control Tri-cure WP 100 g/100 kg seed Tri-cure WP 200 g/100 kg seed Tri-cure WP 400 g/100 kg seed MAIZE YIELD KG/HA
Treatment
Tri-Cure WP applied as a seed treatment on maize across 2 regions in 2015/16
Average maize yield over two trial locations of with untreated and treated maize seeds. Tri-cure WP is a Trichoderma harzianum fungal specie. Twelve statistical plots per region.