New biological product delivers gains in fresh market potatoes

Image: Pictured shows more even grading of fresh potatoes following application of Serenade SOIL ACTIV in a trial near Virginia in South Australia. Harvest assessments revealed the Serenade^® SOIL ACTIV trial plots produced 9.9 per cent higher premium class tubers (by weight) compared with untreated areas and the potatoes were considered to have an improved skin finish.

Following the successful introduction of the biological soil ameliorant, Serenade^® Prime, which has proved particularly useful for improving supply of plant-available nutrients, resulting in improved root growth, Serenade^® SOIL ACTIV is a new soil-optimised addition to the Serenade family from Bayer.

Containing a 30-fold increase in concentration of the QST 713 strain of Bacillus amyloliquefaciens, it provides superior colonisation of plant roots and improved nutrient uptake, resulting in greater root hair development and higher root biomass.

Compared with Serenade Prime application rates of 5-10 L/ha in vegetable crops, Serenade SOIL ACTIV, which also is organically certified (ACO and OMRI), is applied at rates of 1-2 L/ha via a range of soil application methods. The rate reduction also has reduced product handling down to 5 L containers, instead of 10 L, enabling each container to treat a larger area.
 

Image: Untreated potatoes in the Virginia trial, showing a reduced number in the premium range, more uneven grading and poorer skin finish.

Darren Alexander, Territory Business Manager with Bayer Crop Science, said the low application rate and, consequently, water dilution factor is well suited in-furrow applications in potato crops and its good flowability also allowed for easy mixing and filtration.

“In-furrow applications in potatoes don’t use a lot of water. They can include insecticide, fungicide and other products – there is not a lot of room for water. Hence, the low application rate of Serenade SOIL ACTIV is ideal and, with its good flowability as well, helps avoid blockages,’’ Darren said.

“It will also be an advantage for applications in tree crops through dripper lines. Water rates can be as low as 100 L/ha, and 300-500 L/ha when applied by boomspray for vegetables.’’

Replicated strip trials with Serenade SOIL ACTIV were recently coordinated in a fresh market potato crop near Virginia, in the Adelaide Plains region of South Australia, and compared with the standard input application program used by the growing enterprise.

Comprising heavy clay soils and coming out of a cereal crop, the site was cultivated before bed forming and the Serenade SOIL ACTIV was applied via nozzle spray in-furrow as seed potatoes were planted.

“The key to getting maximum benefit from application of Serenade SOIL ACTIV is getting the right amount of product in the right place at the right time,’’ Darren said.

Pack-out results from the trials showed a much more even grading of fresh potatoes where Serenade SOIL ACTIV was applied.

“Yield is not always the prime target. It’s about uniformity and having a higher number of potatoes in the premium range. There was more medium size, premium potatoes,’’ Darren said.

Harvest assessments revealed that the Serenade SOIL ACTIV plots produced 9.9 per cent higher premium class tubers (by weight) compared with the untreated areas, lifting the total premium class weight percentage from the mid 80s into the mid 90s.

The fresh potatoes grown in the Serenade SOIL ACTIV trial strips also were considered to have an improved skin finish, which is important to avoid any downgrading and helps to improve shelf life as well.

At early tuber set, roots of the potatoes grown in the trial strips were analysed by the SA Research and Development Institute (SARDI) to determine any presence of Serenade SOIL ACTIV bacteria.

“The result was positive, confirming that QST 713 strain bacteria had colonised at moderate to high levels and developed with the plant root system. And the grower was very happy,’’ Darren said.

Further potato trials with Serenade SOIL ACTIV are being conducted across the country, including in SA’s Mallee region with the potato industry’s extension and communication project, PotatoLink. 

While limited quantities of Serenade SOIL ACTIV were available last year, there is a greater supply available this year.

Growers interested in further information about the trials or the application of Serenade SOIL ACTIV can contact their local Bayer sales agent or representative.