This article was published as
Kranthi K.R. 2015. Technologies are breaking down -What next? CAI-Vol 19: 11th August 2015. Cotton Statistics and News, Published by Cotton Association of India, Mumbai
Technologies are breaking
down –What next?
K. R. Kranthi
From
the year 2000, over the past fifteen years a few technologies made a huge
difference to cotton production in India. But now, these technologies have
either entered a stage of fatigue, or diminishing returns or near death. At
this stage, it is important to take stock of what is failing, what lies in
shambles and what needs to be done for tomorrow. It is widely acknowledged that
the Bacillus thuringiensis (Bt) based genetically modified (GM) Bt-cotton technology and the new
‘neonicotinoid’ class of insecticides played a strong role in protecting cotton
hybrids from insect pests, thereby resulting in higher cotton production during
the past decade. Data show that the technology benefits are now fading. In this
context it is also pertinent to examine the case of a prospective herbicide
resistant GM technology that has suddenly become debatable because of a recent
technological assessment and declaration by the WHO (World health
organization). If technologies keep falling like cards, -where do we go from
here?
1.
Breakdown
of Bt-cotton: Are bollworms having
the last laugh?
2. Breakdown of new insecticides: Sucking
pests are marauding.3. Downslide of glyphosate: Prospects of (GM) RRFlex (Roundup ready flex) cotton?
4. Breakdown of resistant varieties and introduction of virus-susceptible Bt-cotton hybrids: Cotton leaf curl disease (CLCuD) is back
The bollworms,
whiteflies and cotton leaf curl virus (CLCuV) are the most menacing. Thus far,
until almost three to four years ago, there were a few technologies that were
able to provide relief from these problems. But now these technologies are
fatigued. New ‘neonicotinoid’ class of insecticides that were able to control
the whiteflies have become ineffective. Whiteflies are able to survive almost
all recommended insecticides, only to cause more damage by transmitting the
dreaded leaf curl virus. Bt-cotton
technology has thus far been effective in keeping bollworms under check, but recent
reports from Gujarat and Maharashtra indicate that the efficacy of Bt-cotton can decline sooner or later
from now. The leaf curl virus continues to evolve, resulting in new potent
virulent strains such as the ‘Multan’ and ‘Burewala’ strains that break down
the best of CLCuD-resistant cotton varieties. Because of the technologies
breakdown, the bollworms, whiteflies and virus are laughing all the way. A new
GM cotton technology called Roundup-Ready-Flex (RRFlex®) was just
about to be approved for commercial cultivation in India. But a recent WHO
declaration has pushed the technology into a fresh debate. If potent technologies
continue to breakdown time and again, and with no new technologies in immediate
sight, cotton production can end up at cross roads. Under the current
predicament, it is time to ponder whether this is the correct road towards
sustainability.
Breakdown of Bt-cotton: Are bollworms having the last
laugh?
Is Bt-cotton unable to protect cotton crop
from bollworm damage? Since the last week of July, there were several distress
calls from Gujarat farmers informing of an outbreak like condition of the pink
bollworm on Bollgard-II (BG-II) most of which was sown in May. BG-II has a
potent combination of two Bt genes cry1Ac + cry2Ab. We sent teams from CICR to assess the situation. Indeed
pink bollworm larvae were causing damage to flowers and tender bolls of Bt-cotton Bollgard-II in many parts of
Gujarat. The pink bollworm was reported to be happily chewing up plant parts of
BG-II in some of the fields, unaffected by the Bt-toxins present in the plants.
While a few farmers were resorting to indigenous methods such as ‘cow urine +
calotropis + neem + butter milk etc., to control the pink bollworm menace on
Bollgard-II, some farmers had uprooted their fields.
Imidacloprid –one of the most potent insecticides released in recent times, is no longer effective as seed treatment in Bt-cotton. It is neither effective any longer as foliar spray. Whiteflies and leaf hoppers were exhibiting resistance from 2009 in India to the highly effective new class of insecticides called ‘neonicotinoids’. Imidacloprid which belongs to the neonicotinoid class of insecticides was registered in India in 1993. The chemical was highly effective as seed treatment and foliar sprays at low concentrations in controlling leaf hoppers and whiteflies. Subsequently two more insecticides, thiomethoxam and acetamiprid were approved in 1999.
When
imidacloprid (Gaucho®) was first used as seed treatment for cotton
fifteen years ago, the resultant seedlings would resist sap-sucking pests for
at least 75 to 80 days. ‘Imidacloprid’ is a strong systemic (absorbed and trans-located)
chemical. When used for seed treatment, the chemical is absorbed by the
seedlings through its initial growth and is trans-located through the tissues.
Sap sucking pests suck the plant sap and get killed by imidacloprid. All the
Bt-cotton hybrid seeds are treated with Gaucho because majority of the cotton
hybrids are susceptible to leaf hoppers and whiteflies. I must mention here
that there is a fairly strong genetic association of big boll size with leaf
hopper susceptibility in majority of the cotton hybrids. In other words, if the
bolls are big, the chances of leaf hopper susceptibility are also high. Farmers
prefer big boll hybrids. Without imidacloprid seed treatment, these susceptible
hybrids do not grow properly and yields are reduced because of stunted growth.
Needless to mention, hybrid cotton technology wouldn’t have been as successful
as it has been, without the seed treatment technology. Imidacloprid played a
significant role in protecting Bt-cotton hybrids from sap-sucking insects,
thereby enhancing cotton yields. Over the past 14-15 years, leaf hoppers and
whiteflies were exposed continuously to imidacloprid, thiomethoxam and
acetamiprid, all belonging to the same chemical class called ‘neonicotinoid’,
which are used either as seed treatment or foliar sprays. Because of the
continuous exposure, whiteflies and leaf hoppers developed resistance to the
neonicotinoid class of insecticides. Thus none of these insecticides is now
able to kill the target insects, either as seed treatment or as foliar sprays.
Since whiteflies are able to survive insecticides, they are able to transmit
the leaf curl virus easily.
The
neonicotinoid group of insecticides are now under global scrutiny. On the 1st
December 2013, the European Food Safety Authority (EFSA) banned clothianidin,
imidacloprid and thiamethoxam as seed treatment, soil application and foliar
sprays for a period of two years in all the 28 member states of the European
Union. The ban was
enforced in view of the reports that these chemicals were highly toxic to honey
bees, which were collecting pollen, nectar and guttation fluid from plants that
developed from seeds treated with neonicotinoids. Foliar sprays had more severe
effect. Though the regulatory system in India is yet to contemplate any action,
the neonicotinoid class of chemicals may not be preferred by farmers and seed
companies because of the reduced efficacy. So, is it end of the road for
imidacloprid and the also the other insecticides belonging to the neonicotinoid
class? Also, because big boll hybrids are generally more susceptible to leaf
hoppers and get affected the most by sucking pests, is it also a threat to big
boll hybrid cottons as well?
A combined breakdown of Bt-cotton and insecticides will mean victory of insects over technologies. Is there any fresh arsenal in sight that can help scientists and farmers win the war against insect pests?
The glyphosate
question: Prospects of (GM) RRFlex cotton?
Glyphosate (Roundup® and
other brands) is a chemical herbicide (kills weeds) that has broad spectrum
activity on a wide range of weeds. It is the largest selling herbicide across
the globe. Amongst GM crops, herbicide tolerant crops, mostly, resistance to
glyphosate constitute 154 million hectares, which is 85% of the total area
under GM crops. The glyphosate tolerant GM crops, cotton, maize, soybean and
canola have been extensively cultivated across industrial countries over the
past few years. Though India is yet to approve the commercial cultivation of
glyphosate resistant RRFlex® (Roundup®-Ready) cotton,
glyphosate was being increasingly used for weed control over the past 15-16
years to substitute the acute labour shortages in the country. Since the
herbicide is toxic to conventional crops, the chemical was being carefully
sprayed on weeds using hoods, to avoid any possible drift on the main crop
plants. Until 1996, glyphosate was not used in the country. However, about 1.0
million litres were sprayed in 1998 and by 2010 the usage increased to almost
10.0 million litres. In India, glyphosate is used 30% on tea, 14% on cotton, 13% on sugarcane, 10%
on paddy and 33% on vegetables and fruit orchards. These figures may change
slightly from year to year, but the trend remains more or less the same.
On 15th March 2015, the WHO (World health
organization) declared glyphosate as a probable carcinogen under the category
2A. BG-II-RRFlex® cotton was expected to be resistant to the cotton
bollworms and the herbicide glyphosate. Since labour shortages and wage hikes
were affecting weeding operations, RRFlex® cotton technology was
being considered as the nex-gen GM technology that could have a favourable
impact on the cotton scenario in India. Regulatory testing for bio-safety and
agronomic benefits was in the final stage in India and the technology was
expected to be approved any time. The WHO declaration comes as a blow to the
herbicide and the glyphosate resistant GM crops. It remains to be seen how the Indian
regulatory system reacts to the recent developments and finally what impact it
could have on chemical weed management in India.
Breakdown
of natural resistance: Cotton leaf curl virus (CLCuV) is back
Reports
are being received continuously over the past two weeks from north confirming
heavy infestation of whitefly and virus especially in late sown crop. More than
300 Bt-cotton hybrids were released and introduced into north India after 2006
by private seed companies and almost all of them are susceptible to CLCuD. The
Bt-cotton hybrids replaced all the conventional varieties that were resistant
to the CLCuD. Some of the resistant varieties that were developed earlier by
the public sector institutions are now breaking down before whiteflies and the
leaf curl virus. A variety called LRA-5166 (developed by CICR) was highly
resistant to the leaf curl virus. Apart from being cultivated, LRA-5166 was
commonly used as CLCuD-resistant source by plant breeders to develop new
varieties and hybrids. Even LRA-5166 is breaking down.
The
virus is transmitted by the whiteflies. Just a few insects can inject the virus
into the plants. The severity of infection depends on weather conditions,
strain of the virus and susceptibility of the variety. As the name suggests,
the disease causes leaf curling. It cripples the plant and can be debilitating,
depending on the severity of infection. Early stage of infestation distorts the
leaves and stunts the crop, resulting in significant yield loss. So far the
disease is restricted only to north India and Pakistan. The disease is not
curable. Preventive methods can help in avoiding the disease. For more details
on the CLCuV disease please see my article ‘Cotton leaf curl virus time bomb’
in the CAI ‘Cotton statistics and News’ published on 22nd April 2014.
The CLCuD
was first reported in 1989 in India. There were two outbreaks in 1993 and 1996.
Subsequently through its All India coordinated cotton improvement (AICCIP)
programme, the CICR (Central Institute for Cotton Research) intensified efforts
and identified CLCuD resistant varieties such as LRA-5166, RST9, RS875, RS810,
RS2013, F1861, LH2076, H117, H1126 and resistant hybrids LHH144, CSH198,
CSHH238 and CSHH243 which were popular in north India until the introduction of
Bt-cotton hybrids in 2005. Prior to
2005, the entire area in north India was covered by public sector cotton
varieties. For the development of these varieties, it was mandatory for AICCIP
to approve only CLCuD resistant genotypes for cultivation in north India. The
technology of CLCuD resistant varieties was coupled with several other
strategies such as Desi cotton cultivation (Desi cottons varieties are immune
to CLCuD), early sowing, clean cultivation etc., which resulted in virtual
disappearance of the virus during 1998 to 2006. From 2007 onwards, CLCuD
resurfaced again and is now causing havoc in Punjab, Haryana and Rajasthan.
This is primarily because of the fact that several private seed companies
started releasing Bt-cotton hybrids indiscriminately with scant regard to CLCuD
reaction. These companies were not conscious to the fact that the virus could
resurface any time in an epidemic form, even with the introduction of one or
two susceptible hybrids. Lessons should have been learnt from the Pakistan
situation where CLCuD had started in 1973 in their popular varieties 149-F and
B-557. The disease became an epidemic with the introduction of highly
susceptible varieties such as S12 and CIM-70 in 1988.
August
marks the beginning of a three month crucial phase for cotton in India. In north
India the main troublesome story starts in July itself. Whiteflies mark their
presence. These are small white insects of 1.2mm width. As mentioned in the
previous passages, they transmit the dreaded leaf curl virus. It is widely
known that the best way to control them is through eco-friendly strategies and
habitat management. Many chemical insecticides are known to cause insect
resurgence and outbreaks. Insecticides disrupt the naturally occurring
biological control and some of them induce physiological changes in the insect
which lead to outbreaks. Therefore it is extremely important to start with soft
options such as neem oil based sprays. Under emergency conditions, soil
application of systemic insecticides such as acephate or ethion is preferred.
But, farmers want quick solutions. Many scientists and extension workers play
to the gallery by recommending chemicals which may be acceptable to farmers but
may have long term detrimental effects of the ecosystems. One chemical leads to
-the need for the next. Industry makes hay while the sun shines. More
recommendations are made in a sequence subsequently, but, this time by the
pesticide dealers. Pesticides cocktails are sprayed. By September, whiteflies
dominate and inject the entire region with the leaf curl virus. The crop gets
battered. What comes out clearly at the end of every season is that ‘everyone
advises but nobody listens to anybody’. Finally technologies are overused and
misused to the point that they become useless.
Clearly,
the introduction of large number of Bt-cotton
hybrids which are susceptible to whiteflies and CLCuD- in north India and
discontinuation of CLCuD-resistant varieties has clearly aggravated the virus
problem. But the issue is not just about susceptible Bt-cotton hybrids, over
the past 4-5 years the whiteflies developed high level of resistance to the
most potent neonicotinoid class of insecticides. There are hardly any
recommended chemicals available in the market except one or two newly
introduced insecticides that are effective in controlling whiteflies. But, it
is not insecticides that can give long term relief from the whiteflies and the
virus. It is a set of policies, strategies, recommendations and implementation
that together can have an impact. The disease can only get worse if the CICR
recommendations are not taken seriously.
Conclusion
Technologies
make a difference. Cotton is one of the few crops that have been tremendously
influenced by technological breakthroughs. Technologies with genetic
modification (GM); inter-specific and intra-specific hybrids and varieties;
novel pesticides, management of diseases, insect and nematode pests, weeds,
nutrients, soil, water and climatic aberrations; and mechanization have
contributed significantly to enhanced
productivity. Harnessing the full potential of any technology for the
longest possible time is an art. But, on the technology highway, it is not
uncommon to see dead geese that laid golden eggs. It is sad to see epitaphs of
some fabulous technologies which may have met their grave due to untimely
death. Unfortunately, this happens more frequently in India than anywhere else.
Sometimes this could be because, indiscriminate over-use, commercial
considerations of industrial lobbies over-ride scientific opinion; nobody
listens to anybody, at least in the agricultural sector and invariably the best
technologies end up on the altar of ‘overkill’. In this context it would be
important to point out that, we must learn to respect our past, primarily
because of the lessons that can be learnt from previous disasters. Remember
‘those who forget history are condemned to repeat it’. It remains to be seen as
to how many times we have to repeat history, each time ending up in a bloody
nose and we suffer from memory loss. Technologies are important, but they need
to be sustainable. Sustainability and resilience can be ingrained into
technologies only if they are developed in harmony with nature and in
consonance with local ecology and environment.
As we
mindlessly wander amongst ruins, with hopes to rebuild the falling citadels,
again and again, it is worth remembering Rachel Carson who wrote the following
passages in her book "Silent Spring" (Houghton Miffin, 1962) that
created a storm 50 years ago. The storm continues still.
“The current vogue for poisons has failed
utterly to take into account these most fundamental considerations. As crude a
weapon as the cave man's club, the chemical barrage has been hurled against the
fabric of life a fabric on the one hand delicate and destructible, on the other
miraculously tough and resilient, and capable of striking back in unexpected
ways. These extraordinary capacities of life have been ignored by the
practitioners of chemical control who have brought to their task no "high-minded
orientation," no humility before the vast forces with which they tamper.”
“We stand now where two roads diverge. But
unlike the roads in Robert Frost's familiar poem, they are not equally fair.
The road we have long been travelling is deceptively easy, a smooth
superhighway on which we progress with great speed, but at its end lies
disaster. The other fork of the road the one "less travelled by"
offers our last, our only chance to reach a destination that assures the
preservation of our earth.”
- Rachel Carson, 1962, Silent Spring.
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