The number of products out there claiming benefits to crop production is astounding and trying to keep up with the products worth using while discarding the ones that, despite their marketing pledge, have no real benefit, is a constant challenge.
Last season, a local agribusiness in the Mallee exerted a fairly strong push for a new ‘pulse seed coating’ product with claims that it improved early lentil crop growth and nodulation. Being a relatively low cost product, use was quite widespread.
Recently, gibberellic acid (GA) has also come quietly back in to vogue particularly with lentil growers keen to boost growth and subsequent harvestability, and to get a little more out of short crops to make the most of the strong lentil price.
Although the cost for these products were deemed relatively inexpensive, tight margins mean that even small inputs need to be scrutinised to ascertain their benefits.
With this in mind, BCG established trials in 2016 seeking to quantify the return on investment for seed dressings, zinc and gibberellic use in lentils and vetch.
The trials were carried out at Warmur with the seed dressing trial comparing the effect of the Landmark ‘pulse seed coating’ product with in-crop zinc foliar applications on lentil performance. The gibberellic acid trials examined how application and timing influenced lentil and vetch performance and yield (grain and hay). The findings from these trials were looked at from an economic perspective.
Taking into consideration the exceptional season, the results from this research did not show a significant yield benefit from the use of the pulse seed coating or zinc foliar sprays at the Warmur research site and they were deemed a cost to production.
BCG researcher Kelly Angel said that while there proved to be no benefit from using these products at Warmur, in different circumstances it is possible that a different result would be realized.
“In a different soil type where background levels of the components in these products were low their use may be more feasible,” she said.
Although a yield benefit was not realised from the 2016 trial at Warmur, Ms Angel said it was important to consider if other benefits had resulted from the product’s use such as differences in nitrogen fixing ability which is something that could come as a result of better root development and nodulation.
“In any case, if a grower is looking to use a product such as the ones tested, they should always make sure they have some untreated crop as well so they can make their own assessment about whether it works or not,” she said.
“It may only seem like a drop in the ocean at around $1.50/ha, but if you add it up over your lentil program this cost can become significant.”
Similarly, the use of GA in vetch did not offer benefits that carried through to a time when hay cutting would have occurred. Although, according to Ms Angel, the high disease pressure in 2016, may have confounded the results and she urged growers to consider them with caution.
In lentils, GA use produced mixed results with improved crop height and position of the lowest pod, but a worrying potential for a yield penalty.
The results from the research found that there was between a 300-700kg/ha cost for using GA on lentils at Warmur in 2016.
Ms Angle said that although GA was vastly cheaper than it was 10 years ago, at $8-$9/ha (plus application cost), research carried out in 2016 showed it posed a significant cost to returns.
“The key reason for using GA would be to improve harvestability, in which case, there could be yield benefits and financial benefits as a result of getting more grain into the silo,” she said.
“But it appears the risk of yield loss is also quite large and requires more understanding over different seasons to ensure growers are not wasting their time on products that do not result in a better economic net position.”
A full analysis of the 2016 seed dressing, zinc and GA application research will be published in the 2016 BCG Seasons Research Results compendium to be launched at BCG’s trials review day on February 17. For details go to: www.bcg.org.au
