Page 24 - 21 Cotton SA February 2020

/ PRODUKSIE EN TEGNOLOGIE

LESS CHEMICALS IN THE

ENVIRONMENT

AND MINIMAL IN A T-SHIRT

by Dr Annette Bennett, Cotton SA

The use of chemicals in cotton production has for the control of secondary pests. Before the
long been described as “extreme”. People not introduction of Bt-technology, 10 to 14 chemical
directly involved in the industry often make this sprays were applied, often unnecessarily, to
statement. When the topic of “chemicals used on control the bollworm complex, which also assisted
cotton” is addressed, one should not only refer to in keeping secondary pests at bay. With Bt-
the chemicals used during cotton production in the cotton no sprays are needed for bollworms under
field, but also to those used during the processing normal production conditions, and consequently,
of lint. It is well known that cotton fibres, like all secondary pests have become more prominent
other fibres, are exposed to rigorous washing, and require chemical control just as before.
spinning, bleaching and dyeing. Information In addition to this bollworm-resistant trait, cotton
on the chemicals used during the post-ginning cultivars currently planted also display herbicide
processes is scarce, but when one focusses on tolerance, giving the farmer the opportunity
the production side, the following information is to manage weeds by spraying over the cotton
relevant. plants. Bollgard2 cotton or Bt-cotton with the
With the introduction of new technologies in Roundup Ready Flex trait can be sprayed with
crops, which include genetically modified (GMO) specific glyphosate products (according to the
cotton, also called “Bt-cotton” in some instances, label instructions). This avoids applying a range
the use of pesticides has been drastically of pre- and post-emergence herbicides, which
reduced. All cotton produced in South Africa minimises cultivation practices that contribute to
(apart from that which is planted as the refugia the carbon load on the environment.
as part of a resistance management strategy), Cotton SA received data on chemical usage
contains Bollgard2 technology (Cry1Ac and applied during cotton production under irrigation
Cry2Ab Bt-genes) providing the cotton with a from an accredited Better Cotton Initiative (BCI)
bollworm-resistant trait. This cotton enables the farmer. The BCI is a global cotton production
farmer to apply less, if any, insecticide aimed initiative that enables farmers to farm more
at the bollworm complex. The technology is so sustainably and make use of environmentally
efficient that virtually no insecticides are applied friendly products when necessary. In South
for bollworm control, and only a few are applied Africa approximately 40% of cotton farmers are

Bt-cotton does not affect non-target organisms, Non-Bt-cotton showing infestation by an African
showing here a blister beetle – a pollinator. bollworm (arrow), and a spotted maize beetle
– a pollinator.

24 | Katoen SA \\ Cotton SA