Page 13 - 03 Cotton SA February 2014

Navorsing - Research

in numbers to become primary pests. A resurgence of mirid bugs, and species genes but specifi c targets can also be achieved by gene
other minor pests, was reported in India and China. Colombia reported silencing through RNA interference.
that the incidence and severity of diseases, particularly ramularia A lot of work is also going on to deal with stresses that the cotton plant
(Ramularia areola), anthracnose (Colletotrichum gossypii) and boll rot faces in the fi eld. Drought tolerant cotton is among many new avenues
(disease complex), is higher in biotech cotton than in conventional being extensively researched and some of the new traits are close to
cotton varieties.
commercialization. A number of potential genes have been shortlisted
A rise in the incidence of diseases could be related to changes in the for fi bre quality improvement, including a gene from spinach, a spider
plant canopy and fruit allocation on the plant in a biotech cotton silk gene, and a gene from the silk worm. Good progress has already
variety compared to a parental conventional variety. been made to develop ultra-low gossypol cotton thus increasing the
nutritional value of cotton seed.
Most biotech cotton producing countries expressed concerns over
the development of resistance by target pests. Resistance is likely if
appropriate measures are not taken to delay and avoid resistance LABELLING OF BIOTECH FOODS
to a specifi c toxin. However, refuge requirements as a resistance
management tool are being relaxed or ignored in some countries. It is The U.S. government decided against labelling food derived from
also important to monitor the level of toxin expression at various stages biotech crops years ago as these products did not demonstrate safety
of growth and in diff erent plant parts. Sub-standard expression of Bt concerns for humans or animals. The government has long held the
toxin in biotech varieties only accelerates the resistance development policy that biotech food products are not “materially diff erent” from
process. Gene stacks for a particular trait, but of unrelated modes of conventional food products and, therefore, need no labeling. U.S.
action, provide an excellent option for resistance management, apart consumers consistently list biotechnology as a low priority.
from enhancing the trait effi cacy. However gene stacking can add to
increased seed costs. The European Union began requiring labelling their biotech foods in
1997 in response to consumers’ concerns. Other countries including
Russia, Japan, Australia, New Zealand, Turkey and China have also
mandated labelling. In Australia, biotech foods and ingredients which
BIOTECH COTTON SEED COST
contain novel DNA or protein that has come from an approved biotech
Private companies charge a fee for the technology in biotech cotton food must be labelled with the words ‘genetically modifi ed’. However,
and most countries reported concerns about the cost of biotech foods that do not need to be labelled include highly refi ned foods,
seed, which is considerably more expensive than that of non-biotech such as sugars and oils, where the process has removed DNA and
conventional planting seed. protein from the food.
Farmers have often expressed their opposition to the high cost of In the EU, biosafety laws mainly focus on food and feed. Biotech cotton
technology in cotton and, in some countries measures were taken to fi bre is not included in Europe’s biosafety regulations although cotton
lower the cost of planting seed. The cost of biotech cotton seed has seed, meal, and oil are subject. Turkey’s new Biosafety Law that became
been prohibitive in rainfed production areas in South Africa where eff ective in September 2010, depending on interpretation, could
yields are lower. Technology fees for the same event may diff er include fi bre produced from biotech varieties. This law is probably the
among diff erent countries and even in diff erent regions of the same strictest among countries with biosafety regulations in place.
country. However, according to the owners of the events, the value is
proportional to the benefi ts provided to farmers.
BIOSAFETY
At the international level, the Cartagena Biosafety Protocol, Codex
NEW BIOTECH TRAITS
Alimentarius, Food & Agriculture Organization of the United Nations,
Biotechnology applications in agriculture provide tools to modify lnternational Plant Protection Convention, Organization for Economic
plants precisely with desired traits and cotton farmers around the Cooperation & Development and the World Health Organization have
globe anticipate the commercial availability of a range of new biotech or claim a role in regulation of agricultural biotechnology and standard
traits in the near future. It is especially important to develop biotech setting. Of these, the Cartagena or Biosafety Protocol (BSP) is most
cottons to assist in the prevention of the distribution of phytosanitary specifi cally focused on biotech crops and bears directly on the trade
problems such as Fusarium and Verticillium wilt as well as important of biotech commodities.
regional pests and diseases, especially the boll weevil in Latin America Adverse environmental impacts and risks to human health are the two
and Cotton Leaf Curl Virus in Pakistan and India.
most important clauses of the Cartagena or Biosafety Protocol. Public
There is also a need to strengthen the technology with additional genes perception of biotechnology is one of the critical issues in the further
through gene stacking to ensure long-term sustainability of various development, adoption, and free trade of biotech products. Public
events. There are several sources other than Bacillus thuringiensis that perception has resulted in a variety of regulatory restrictions among
have been used to isolate insecticidal genes and genes from endo- producing and consuming countries of biotech products and anti-
symbiotic bacteria of nematodes, Xenorhabdus and Photorhabdus biotech groups have played a big role in stimulating public debate
have been actively considered for the development of transgenic that is often times not based on science but on philosophical theories
crops. and fear.
Amongst animal sources, anti-chymotrypsin, anti-elastase, chitinase, Critics continue to raise issues that cannot be proven scientifi cally.
cholesterol oxidase, and anii-trypsin have been isolated from the The crystal (Cry) toxins of Bacillus thuringiensis that are deployed in
tobacco hornworm and used to develop biotech cotton resistant to biotech cotton are safe for human consumption. The human stomach
sucking pests and lepidopteran insects. Other gene sources include is acidic and contains proteases like pepsin, which degrade the Bt
chitinases, glucanases, peroxidase, and tryptophan decarboxylase protein quickly. More importantly, the human intestine lacks the
from various plant sources which may also be useful transgenes to specifi c receptors to which the activated Bt proteins bind and initiate
develop insect and disease resistant cotton. The technology carries physiological eff ects.
huge potential and does not only involve inserting foreign or intra
Koot Louw – Katoen SA

Katoen SA Cotton 13 Februarie • February 2014