The role of biostimulants in providing nutrition to tropical crops is increasing each season in Queensland thanks to the ever-evolving biostimulant fertiliser range by De Sangosse Australia, under the guidance of regional manager Ben Itzstein.

Mr Itzstein said sun protection, thermoregulation, and complete nutrition throughout all stages of development – coupled with improved stress resistance, are helping ensure tropical crops utilising biostimulants are flourishing.

“Key biostimulant products Fertigofol Ultra, Sealeaf Origin, and Reflect provide growers with well-researched nutritional solutions for tropical crops.

"The nutritional formulation of these three products, combined with specific L-amino acids (plant-derived) and/or seaweed, can provide agronomic benefits and solutions to growers across many systems, especially with their added compatibility with regularly-used insecticides and fungicides. This is a major benefit when applying foliar fertilisers.”

Continuous trial work and farm demonstrations of these products have been a large focus for Mr Itzstein in supporting the performance of these tropical crops. Trials have been conducted on citrus and avocado systems, as well as a focus on capsicum production.

Untreated Hass avocados showing characteristic leaf yellowing. Childers September 2022,
vs. Healthy Hass avocados treated with 5L/ha of Fertigofol Ultra at fruit set. Childers, September 2022. 

Fertigofol Ultra

“Providing nutrition throughout all stages of plant development, especially in citrus crops, Fertigofol Ultra is a complete formulation, designed to rebalance the nutritional status of plants, boosting photosynthesis and stimulating growth,” he said.

“Fertigofol Ultra is an NPK mix (plus magnesium and sulfur) combined with all key micronutrients in an EDTA-chelated form. Coupled with 19 amino acids to aid with nitrogen metabolism, chlorophyll production, energy, flower production, and vegetative development, it is easily absorbed and assimilated by the plant.

“Intended for foliar use, ongoing work and use in a variety of tree crops such as avocados, citrus, lychees, and macadamias has demonstrated its benefits during periods of high stress, including applications at fruit-set, fruit-drop periods, after environmental stress, and under heavy crop load.

Mr Itzstein said due to its formulation, Fertigofol Ultra is also an effective post-harvest or pre-flower spray in citrus, to aid in recovery due to its high amino acid content, as well as correcting nutritional deficiencies before beginning the next cycle.

Sealeaf Origin

“Supporting pre- and post-flowering to help with flower strength, pollination, fruit set, and early fruit development, as well as frost resistance in tropical crops are all key benefits of the biostimulant product, Sealeaf Origin,” he said.

Sealeaf Origin is a seaweed and amino acid mixture. De Sangosse's seaweed range sources and uses Ascophyllum nodosum from the Northern Atlantic Ocean. Ascophyllum experiences extreme conditions, including temperature change, solar radiation, and dry atmospheric conditions.

“Mr Itzstein said by foliar-applying Ascophyllum, it is aimed to provide seaweed molecules that will increase the plant's ability to resist stressful situations.

Supporting De Sangosse's research, independent reviews have demonstrated that Ascophyllum has numerous benefits, including favourable cytokinin and gibberellin extracts, along with increased calcium uptake.

“Combine these with seven amino acids to enhance photosynthesis and nitrogen metabolism, amplify auxin within the plant, and provide stress resistance, Sealeaf Origin can be used at numerous stages throughout plant development,” Mr Itzstein said.

Future trials to be conducted in 2023 include avocados, where analysis of flower and fruit retention will be conducted, along with corresponding yields. "This follows many reports that due to ongoing wet and cold weather in 2022, a short flowering window was observed, reducing fruit set and yields (especially in the Hass variety)," he said.

“By applying Sealeaf, the longevity, and viability of the flowers will hopefully be strengthened, increasing pollination.”

Reflect

Providing thermoregulation and sun protection for tropical crops, Reflect is the latest biostimulant developed by De Sangosse and launched in Australia late last year. A calcium-silicon liquid formulation, with added Ascophyllum, Reflect is formulated to help reduce the impact of heat stress throughout plant and fruit development.

Mr Itzstein said Reflect includes a patented deep-sea sedimentary calcite-calcium. Once this is absorbed, it splits into CO2 and calcium, activating photosynthesis and aiding the opening of the stomata.

“This phenomenon enables plants to function and develop even under heat or water stress. The addition of silicon and seaweed provides a complete ‘thermo-regulator’ effect, reducing the effect of solar radiation on the plant canopy and fruit. Initial trial results in France have demonstrated temperature reduction on the leaf surface.”

Trial work on Murcott mandarins, mangoes, and pineapples is currently being analysed, to reduce sunburn-damaged fruit. Mr Itzstein has also begun farm trials on capsicums with key retailers and growers, to analyse Reflect's benefits in battling planting shock and hot, humid conditions throughout plant growth and fruit development.

Researched, sourced, and manufactured in France, he said De Sangosse's biostimulant range provides a complete plant nutrition package for all horticultural and tropical agriculture systems.