Farmer's Weekly (South Africa)
A new approach to soya bean cultivar categorisation
In this article, Dr Antony Jarvie of Podsquad, and independent consultant to Corteva Agriscience, explains the new approach adopted by Pannar to better align the categorisation of soya bean cultivars with the needs of South African farmers. He also review
The restrictions on gatherings and movement associated with the coronavirus disease (COVID-19) pandemic came at a time when agronomists around South Africa were preparing to host field days for farmers at which they could demonstrate the new products for the 2020/2021 planting season. Seed group Pannar Seed, which is owned by Corteva Agriscience, was unable to go ahead with a number of its planned farmers’ days.
To cater for those farmers who could not attend farmers’ days this year, Pannar released a video series that captured the essence of their field demonstrations. Having viewed the videos and reviewed the data prepared for the demonstrations, I am impressed with the way that the Pannar brand has chosen to group their soya bean varieties into growth classes.
CATEGORISATION BY GROWTH CLASS
The conventional way of categorising cultivars is to use the international maturity group (MG) scale. In South Africa, the applicable maturity groups are MG 4 through to MG 8, and this method can be used to describe the cultivar accurately. The problem with this description in South Africa, however, is that cultivar adaptation patterns broach the maturity groups.
For example, a farmer looking to choose the best MG 5 variety will inevitably end up selecting a variety with a relative maturity group of MG 5,8 or MG 5,9, which is very nearly an MG 6. Having set out to choose a cultivar from the lower side of the spectrum, the farmer will then be drawn by adaptation patterns into choosing a variety that falls more into the medium growth class.
Pannar has found a solution to this problem by consolidating the MG 4,5 to MG 5,4 groups into an ‘early’ growth class, the MG 5,5 to MG 6,4 varieties into ‘medium’, and MG 6,5 to MG 7,4 varieties into ‘late’.
The difference in maturity between an MG 5,9 and MG 6
replacement for PAN 1454R. With reorganisation related to the implementation of growth classes, PAN 1454R indirectly made way for PAN 1555R in the cultivar range.
Although PAN 1623R was still commercially competitive, Pannar retired the cultivar to make room for PAN 1663R and PAN 1644R in its range.
The way in which Pannar has positioned the medium growth class means that approximately half of the national soya bean crop is derived from this class. The cultivar PAN 1521R currently does a sterling job in delivering a large part of the national crop, but this is too large an area to commit to a single genotype. PAN 1555R has therefore stepped off the bench to assist. This new release has a strongly branched architecture and is well suited to tough environments and unpredictable weather conditions.
GROWTH CLASSES MAKE CULTIVAR CHOICE EASIER FOR FARMERS
Another new release, PAN 1663R, also falls into the medium growth class, but has a role at the higherpotential end of the production spectrum. It has excellent standability and can tolerate the high plant populations associated with irrigated environments.
As noted above, PAN 1644R entered the Pannar range at the expense of PAN 1623R. Removing a cultivar is always disappointing, but based on my observations, I can confidently say that PAN 1644R is a worthy replacement. It is versatile and can perform in all the soya bean production regions. This versatility enables the variety to endure unseasonal and unexpected weather conditions that are recurring more frequently due to the impact of climate change.