ChangingCottonLandscapeNeilForrester

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• Disease tolerance, especially Fusarium and Verticillium tolerance in Australia and CLCV tolerance in India and Pakistan • Nematode tolerance in the US • Yield enhancement (including improved photosynthetic ability) • Improved nutrient use efficiency • Tolerance to high temperatures • Chilling tolerance • Salt tolerance • Water logging tolerance • Improved oil quality (e.g. healthier high oleic cottonseed oils) • Improved fibre quality (length, strength etc) • Fabric quality (e.g. Bayer’s work on flame retardance, improved chemical reactivity and anti- wrinkle) • Coloured cotton (so far unsuccessful) • Novel insect control products (e.g. Dow’s work on toxins from Photorhabdus and Xenorhabdus symbionts from entomopathogenic nematodes) and toxins from spiders, scorpions, ant lions, parasitic wasps, etc., and lectins, cyclotides, monoterpenes, peroxidases, etc. There are also a range of new biotechnologies to facilitate cotton breeding. Recent discoveries in cotton genomics have facilitated new biotechnology tools to help cotton breeders breed better cottons. New Marker-Aided Selection tools will help breeders select for rare traits of economic value or those left behind during the domestication of crops. Biotechnology breakthroughs will allow much of this previously tedious work to be conducted more efficiently by moving testing from the field to the lab. Gene chip microarrays will also allow the identification of large numbers (+ 10,000) of short sequences of DNA or RNA at one time which will allow the simultaneous tracking of many genes for complex traits such as fibre quality and stress tolerance. 5. Insecticide Resistance Management I have already addressed the issue of preferentially using Bt genes in pyramided stacks rather than deploying them individually and sequentially. A number of researchers have modeled the various factors which can affect the rate of anticipated resistance development to Bt toxins in 30
transgenic plants. In the following figure, Dr. Rick Roush 5 has modeled the impact of either using two genes stacked together from the start such as in Bollgard 2 (pyramid line in the figure) or using one of them alone first, such as in Bollgard 1, and then introducing the second after resistance has developed to the first gene (sequence line in the figure). The starting resistance gene allele frequency which is normally used is 10 -4 (I in 10,000). There are normally 4-5 generations of American bollworm per year and of these about 2-3 would be subject to selection pressure each year, so the number of generations for 50% of the population to develop resistance (on the vertical axis in the figure, note this is a log scale) should be divided by 2-3 to work out the anticipated viability of a technology in years. So pyramided gene technologies would be anticipated to last 150 to 250 years and single genes used sequentially 6-9 years. Clearly, it is highly advantageous to progress to pyramided (Cry 1Ac + Cry 2Ab) Bollgard 2 before using up the efficacy of Cry 1Ac alone in Bollgard 1 and the triple gene stack Bollgard 3 would be even better. The role of refuges is also important to discuss. In Australia and the US, separate conventional refuge crops were mandated to be used to allow production of Bt susceptible moths to allow dilution of any resistant moths selected in the transgenic Bt crops. The size of these compulsory refuge crops varied from 5-10% (if they were left unsprayed) of the total planted Bt cotton area in the US and Australia, respectively. A similar requirement was mandated in India but adoption of these conventional unsprayed refuge areas will always be problematic in small scale agriculture such as practised in India, China and elsewhere. In these cases, it is argued that 5 Roush, R. T. 1997. Managing Resistance to Transgenic Crops. pp. 271-294, in Advances in Insect Control: The Role of Transgenic Plants, N. Carozzi and M. Koziel, eds. Taylor and Francis (London) 31
Page 1: Changing the Cotton Landscape in Pa
Page 5: Preface The importance of improving
Page 8 and 9: Acronyms AARI Ayub Agricultural Res
Page 10 and 11: Millions of Bales (170 kgs) Yield (
Page 12 and 13: Millions of bales (170 kgs) 35.0 30
Page 14 and 15: 4.1b/year in extra lint, oil and me
Page 16 and 17: CLCV susceptible variety in the Ind
Page 18 and 19: (Feb/March) of part of their cotton
Page 20 and 21: The following table presents data o
Page 22 and 23: 96.1%, respectively). High levels o
Page 24 and 25: for transgenic seed production othe
Page 26 and 27: 2) Ensure all private seed sector c
Page 28 and 29: Logistical problems It will be very
Page 30 and 31: the introduction of Roundup Ready F
Page 32 and 33: eview and will not be discussed fur
Page 34 and 35: Following is a list of insect toler
Page 36 and 37: The key factors affecting the devel
Page 40 and 41: whatever natural refuges are availa
Page 42 and 43: The models above clearly indicate t
Page 44 and 45: 7. Summary of Recommendations 1) En
Page 46 and 47: case, we need to carefully examine
Page 48 and 49: Stakeholders Engaged for this Study

ChangingCottonLandscapeNeilForrester

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