scholarly journals Bt cotton seed purity in Burkina Faso: Status and lessons learnt

2020 ◽  
Author(s):  
Larbouga Bourgou ◽  
Ester Kargougou ◽  
Mahamadou Sawadogo ◽  
Michel Fok

Abstract BackgroundSince the commercial release of Bt cotton the issue of seed purity in producers' fields has been little addressed and in an unbalanced way when it was. It is well documented that the loss of purity in conventional seeds has endangered the continuation of organic cotton production. However, studies are rare on the purity of Bt-cotton seeds despite its implications on the effectiveness and sustainability of their use.This paper compensates for the mentioned lack of literature by analyzing data collected in 2015 in Burkina Faso, namely results of ELISA tests on samples of seeds from 646 fields grown with conventional or Bt varieties. ResultsAccording to the conservative criteria retained to declare the presence of Bt gene (more than 10% and 90% of controlled seeds for conventional and Bt variety, respectively), seed purity was very questionable for both types of varieties. For the conventional variety, the presence of Bt gene was observed on 63.6 and 59.3% of samples for Cry1Ac and Cry2Ab, respectively. Only 29.3% of samples corresponded to pure conventional seeds while 52.2% were double Bt seeds. Conversely, for the Bt variety, the presence of Bt gene was observed on 59.6 and 53.6% of samples for Cry1Ac and Cry2Ab, respectively. Actually BG2 seeds with both Bt genes were found in 40.4% of samples against 27.2% of samples of actually conventional seeds while the remaining of 32.4% of samples corresponded to single Bt gene seeds.Two factors affected the severe lack of seed purity. As regard to conventional seeds, it clearly resulted from a phenomenon of contamination, indicative of a failure in adjusting the seed production scheme to the use of Bt-cotton. With regard to the Bt variety, the lack of purity of the original seeds provided to Burkina Faso accounted and should even be the major factor.The observed lack of seed purity is a threat to the initiative of organic cotton production, albeit a very minor production mode in the country. It also calls upon the effectiveness and furthermore the sustainability of Bt cotton to control target pests. ConclusionOur results show the extent of purity loss when no especial attention is paid to the preservation of seed purity. Pure conventional seeds could totally vanish while Bt seeds become a combination of seeds of various types encompassing or not the expected Bt genes.Any country willing to embark the use of Bt cotton, or to resume this use like Burkina Faso, must previously adjust its seed production scheme and enforce its operation. This is a condition to preserve pure seeds both to enable the launch or the continuation of identity-cotton production and to ensure a sustainable effectiveness of Bt-cotton. The mentioned condition implies that seed purity must be checked and the related information shared.

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Larbouga BOURGOU ◽  
Ester KARGOUGOU ◽  
Mahamadou SAWADOGO ◽  
Michel FOK

Abstract Background Since the commercial release of Bt cotton in Burkina Faso in 2009, the issue of seed purity in producers’ fields has rarely been addressed in an unbiased and objective manner. The potential for contamination of conventional seed varieties with Bt traits and the consequent threat to the continuation of organic cotton production has been documented. However, studies are rare on the varietal purity of Bt cotton seeds, despite the implications for the effectiveness and sustainability of their use. This paper compensates for the lack of research on the varietal purity of cotton seeds in Burkina Faso by reporting the results of Enzyme linked immunosorbent assay tests collected in 2015 on samples of both conventional and Bt varieties from 646 fields. Results According to the conservative criteria used to declare the presence of a Bt gene in a given variety (more than 10% of seeds of conventional variety exhibit Bt traits, and at least 90% of seeds of Bt variety exhibit Bt traits), seed purity was very questionable for both types of variety. For the supposedly conventional variety, the Cry1Ac gene was observed in 63.6% of samples, the Cry2Ab gene was observed in 59.3% of samples, and both genes were detected in 52.2% of the seed samples. Only 29.3% of the seeds that were supposed to be of conventional type contained no Bt genes. Conversely, for the labeled Bt variety, the Cry1Ac gene was found in only 59.6% of samples, the Cry2Ab gene was found in 53.6% of the samples, and both genes were found in 40.4% of the samples. Finally, for the seeds that were supposed to contain both genes (Bollguard 2), both Cry1Ac and Cry2Ab genes were found in only 40.4% of the samples, only one of the genes was found in 32.4% of the samples, and 27.2% of the seeds in the samples contained neither. Two factors are responsible for the severe lack of seed purity. First, conventional varieties are being contaminated with Bt traits because of a failure to revise the seed production scheme in Burkina Faso to prevent cross-pollination. Second, the original Bt seeds provided to Burkina Faso lacked varietal purity. The organic sector plays a very minor role in the cotton sector of Burkina Faso (production of organic cotton totaled 453 t in 2018/2019, out of national cotton production of 183 000 t). Nevertheless, the lack of purity in conventional seed varieties is a threat to efforts to expand certified organic cotton production. The poor presence of Bt proteins in supposed Bt varieties undermines their effectiveness in controlling pests and increases the likelihood of the development of resistance among pest populations. Conclusion Our results show the extent of purity loss when inadequate attention is paid to the preservation of seed purity. Pure conventional seeds could vanish in Burkina Faso, while Bt seeds do not carry the combination of the expected Bt traits. Any country wishing to embark on the use of Bt cotton, or to resume its use, as in the case of Burkina Faso, must first adjust its national seed production scheme to ensure that procedures to preserve varietal purity are enforced. The preservation of varietal purity is necessary to enable the launch or the continuation of identity-cotton production. In addition, the preservation of varietal purity is necessary to ensure the sustainable effectiveness of Bt cotton. In order to ensure that procedures to preserve varietal purity are observed, seed purity must be tested regularly, and test results must be published.


2020 ◽  
Author(s):  
Larbouga Bourgou ◽  
Ester Kargougou ◽  
Mahamadou Sawadogo ◽  
Michel Fok

Abstract [Background] Since the commercial release of Bt cotton in Burkina Faso in 2009, the issue of seed purity in producers' fields has rarely been addressed in an unbiased and objective manner. The potential for contamination of conventional seed varieties with Bt traits, and the consequent threat to the continuation of organic cotton production has been documented. However, studies are rare on the varietal purity of Bt cotton seeds, despite the implications for the effectiveness and sustainability of their use. This paper compensates for the lack of research on the varietal purity of cotton seeds in Burkina Faso by reporting the results of ELISA tests collected in 2015 on samples of both conventional and Bt varieties from 646 fields. [Results] According to the conservative criteria used to declare the presence of a Bt gene in a given variety (more than 10% of seeds of conventional variety exhibit Bt traits, and at least 90% of seeds of Bt variety exhibit Bt traits) seed purity was very questionable for both types of variety. For the supposedly conventional variety, the Cry1Ac gene was observed in 63.6% of samples, the Cry2Ab gene was observed in 59.3% of samples, and both genes were detected in 52.2% of the seed samples. Only 29.3% of the seeds that were supposed to be conventional contained no Bt genes. Conversely, for the labeled Bt variety, the Cry1Ac gene was found in only 59.6% of samples, the Cry2Ab gene was found in 53.6% of the samples, and both genes were found in 40.4% of the samples. Finally, for the seeds that were supposed to contain both genes (Bollguard 2), both Cry1Ac and Cry2Ab genes were found in only 40.4% of the samples, only one of the genes was found in 32.4% of the samples, and 27.2% of the seeds in the samples contained neither gene. Two factors are responsible for the severe lack of seed purity. First, conventional varieties are being contaminated with Bt traits because of a failure to revise the seed production scheme in Burkina Faso to prevent cross fertilization. Second, the original Bt seeds provided to Burkina Faso lacked varietal purity. The organic sector plays a very minor role in the cotton sector of Burkina Faso (production of organic cotton totaled 453 tonnes in 2018/19, out of national cotton production of 183,000 tonnes). Nevertheless, the lack of purity in conventional seed varieties is a threat to efforts to expand certified organic cotton production. The poor expression of Bt traits in supposedly Bt varieties undermines their effectiveness in controlling pests and increases the likelihood of the development of resistance among pest populations. [Conclusion] Our results show the extent of purity loss when inadequate attention is paid to the preservation of seed purity. Pure conventional seeds could totally vanish in Burkina Faso, while Bt seeds do not carry the combination of the expected Bt traits. Any country wishing to embark on the use of Bt cotton, or to resume its use, as in the case of Burkina Faso, must first adjust its national seed production scheme to ensure that procedures to preserve varietal purity are enforced. The preservation of varietal purity is necessary to enable the launch or the continuation of identity-cotton production. In addition, the preservation of varietal purity is necessary to ensure the sustainable effectiveness of Bt cotton. In order to ensure that procedures to preserve varietal purity are observed, seed purity must be tested regularly, and test results must be published.


2020 ◽  
Author(s):  
Larbouga Bourgou ◽  
Ester Kargougou ◽  
Mahamadou Sawadogo ◽  
Michel Fok

Abstract BackgroundSince the commercial release of Bt cotton in Burkina Faso in 2009, the issue of seed purity in producers' fields has rarely been addressed in an unbiased and objective manner. The potential for contamination of conventional seed varieties with Bt traits and the consequent threat to the continuation of organic cotton production has been documented. However, studies are rare on the varietal purity of Bt cotton seeds, despite the implications for the effectiveness and sustainability of their use.This paper compensates for the lack of research on the varietal purity of cotton seeds in Burkina Faso by reporting the results of Enzyme linked immunosorbent assay tests collected in 2015 on samples of both conventional and Bt varieties from 646 fields.ResultsAccording to the conservative criteria used to declare the presence of a Bt gene in a given variety (more than 10% of seeds of conventional variety exhibit Bt traits, and at least 90% of seeds of Bt variety exhibit Bt traits), seed purity was very questionable for both types of variety. For the supposedly conventional variety, the Cry1Ac gene was observed in 63.6% of samples, the Cry2Ab gene was observed in 59.3% of samples, and both genes were detected in 52.2% of the seed samples. Only 29.3% of the seeds that were supposed to be of conventional type contained no Bt genes. Conversely, for the labeled Bt variety, the Cry1Ac gene was found in only 59.6% of samples, the Cry2Ab gene was found in 53.6% of the samples, and both genes were found in 40.4% of the samples. Finally, for the seeds that were supposed to contain both genes (Bollguard 2), both Cry1Ac and Cry2Ab genes were found in only 40.4% of the samples, only one of the genes was found in 32.4% of the samples, and 27.2% of the seeds in the samples contained neither.Two factors are responsible for the severe lack of seed purity. First, conventional varieties are being contaminated with Bt traits because of a failure to revise the seed production scheme in Burkina Faso to prevent cross-pollination. Second, the original Bt seeds provided to Burkina Faso lacked varietal purity.The organic sector plays a very minor role in the cotton sector of Burkina Faso (production of organic cotton totaled 453 tonnes in 2018/2019, out of national cotton production of 183 000 tonnes). Nevertheless, the lack of purity in conventional seed varieties is a threat to efforts to expand certified organic cotton production. The poor presence of Bt proteins in supposedly Bt varieties undermines their effectiveness in controlling pests and increases the likelihood of the development of resistance among pest populations.ConclusionOur results show the extent of purity loss when inadequate attention is paid to the preservation of seed purity. Pure conventional seeds could vanish in Burkina Faso, while Bt seeds do not carry the combination of the expected Bt traits. Any country wishing to embark on the use of Bt cotton, or to resume its use, as in the case of Burkina Faso, must first adjust its national seed production scheme to ensure that procedures to preserve varietal purity are enforced. The preservation of varietal purity is necessary to enable the launch or the continuation of identity-cotton production. In addition, the preservation of varietal purity is necessary to ensure the sustainable effectiveness of Bt cotton. In order to ensure that procedures to preserve varietal purity are observed, seed purity must be tested regularly, and test results must be published.


2019 ◽  
Vol 11 (22) ◽  
pp. 6353 ◽  
Author(s):  
Vonzun ◽  
Messmer ◽  
Boller ◽  
Shrivas ◽  
Patil ◽  
...  

Resistance against cotton bollworm is one of the main arguments for the use of genetically modified (GM) Bt cotton around the globe. The use of GM is prohibited in organic systems and thus the remunerative value of organic cotton cultivation depends on effective bollworm control. In this study, we investigated the extent of bollworm and sucking pest damage in 68 different hybrid and varietal lines of Gossypium hirsutum and varietal lines of G. arboreum at two different locations with contrasting soil fertility and water dynamics. The damage potential of bollworms was assessed from open capsules at two time points. Sucking pests were assessed at three time points using a scoring method. G. arboreum varietal lines and G. hirsutum hybrids were on average significantly more tolerant than G. hirsutum varietal lines to bollworm under fertile and irrigated situations. For sucking pests, the G. arboreum varietal lines were clearly more tolerant than G. hirsutum hybrids and varietal lines. Since, recently, pink bollworm (Pectinophora gossypiella) became resistant against Bt cotton and pressure of sucking pests severely increased, screening of genetic resources and systems-based cotton breeding for bollworm and sucking pest tolerance will improve sustainability of organic and conventional cotton production.


2020 ◽  
Vol 14 (3) ◽  
pp. 869-882
Author(s):  
Larbouga Bourgou ◽  
Windpouiré Vianney Tarpaga ◽  
Sidiki K. Diane ◽  
Denys Sanfo

Le coton du Burkina Faso est presqu’entièrement exporté ; les variétés cultivées doivent régulièrement répondre aux exigences du marché. Une fratrie de lignées de cotonnier a été comparée à deux variétés, FK37 et Stam 59A, respectivement dans les zones cotonnières humides et sèches de 2006 à 2009, pour mettre en exergue celle qui améliore les performances agronomiques et technologiques de fibre de ces témoins. A l’issue d’évaluations multilocales, FK64 et FK69 ont été identifiées comme de potentielles nouvelles variétés et testées en milieu paysan. Dans les zones humides, FK64 et FK69 n’ont pas apporté d’amélioration significative ; il est inopportun de les y vulgariser. Dans les zones sèches, FK64 a le mieux performé et a été retenue pour y être vulgarisée. Elle apporte un surplus en pourcentage fibre (+ 0,41%) et en seed index (+ 0,35 g). Aussi, elle apparait meilleure que Stam 59A pour la longueur (+ 1,44 mm) et la ténacité (+ 1,90 g/tex), deux caractéristiques déterminantes du marketing de la fibre. Avec la suspension du coton Bt et le retour à la culture conventionnelle, FK64 lancée en culture commerciale a convaincu. Elle pourrait être candidate à la transformation en cas de retour dans la technologie Bt.Mots clés: Evaluations multilocales, tests variétaux, caractéristiques agronomiques, caractéristiques technologiques, Burkina Faso.   English Title: Assessment and selection of a cultivar of cotton (FK64, Gossypium hirsutum L.) in Burkina Faso Cotton produced in Burkina Faso is almost entirely exported; so cultivars must be developed following the market demand. A sibling of cotton lines was compared to two varieties, FK37 and Stam 59A, respectively in humid and dry cotton production areas between 2006 and 2009 to highlight which one enhances agronomic and fiber quality performances compared to the local control. After multilocation trials, FK64 and FK69 were highlighted as promising news varieties then evaluated under farmer’s conditions of production. In the humid areas, FK64 as well as FK69 did not bring any significant improvement; it was not recommended to release any of them there. In the dry production areas, FK64 performed better, then it was retained to be possibly popularized. It brings a surplus in terms of ginning out turn (+ 0,41%) and seed index (+ 0,35 g). Moreover, it outperformed Stam 59A in fiber length (+ 1,44 mm) and strength (+ 1,90 g/tex), two major cotton fiber marketing properties. At the morrow of the suspension of the Bt cotton and back to conventional production, FK64 was launched in commercial production and it convinced. It could be aspirant to Bt introgression in case country resumes back to the technology.Keywords: multilocation trials, varietal trials, agronomical characteristics, fiber properties, Burkina Faso.


2020 ◽  
Vol 36 (4) ◽  
Author(s):  
Leandro Nogueira Ramos ◽  
Nara Oliveira Silva Souza ◽  
Michelle Souza Vilela

The objectives were to study the behavior of fifteen pre-commercial upland maize hybrids, analyze their agronomic performance regarding grain yield, and evaluate productivity components, as well as morpho-agronomic characteristics, in the Midwest Region of Brazil. Two experiments were conducted in the municipalities of Formosa-GO and Planaltina-DF, 2016/17 crop year. Both consisted of five pre-commercial maize hybrid platforms (HPA252, HPB262, HPB621, HPB646, and HPD354). Each platform consisted of three different versions: conventional, transgenic with a Bt gene that expresses the protein Cry1F, and transgenic with two Bt genes that express the proteins Cry1F and Cry1AB. The experiment was randomized blocks with four replications. The experimental plot was four lines five meters long considering the two central lines as useful. The lines were spaced 0.75 meters apart, and the final density was five plants per linear meter. To estimate grain yield, the plots were harvested, and the weight was extrapolated to kg.ha-1. The moisture was standardized at 14%. Data were submitted to analysis of variance, and the means were compared by Tukey test at 5% probability using the Sisvar software. Grain yield between treatments ranged from 8,381 to 12,908 kg.ha-1, and the average yield was 11,234 kg.ha-1. The parameters evaluated were divided into two groups. The first group contained parameters determining grain yield: grain depth, thousand grains weight, number of rows of grains, number of grains per row, and grain yield. The second group contained morpho-agronomic parameters that directly interfere with resistance to lodging and plant breaking: plant height, ear insertion height, and mean stem diameter. There was no direct effect of the transgenes on the evaluated hybrids since the classification of productivity was not divided into conventional and transgenic classes. It is suggested that the HPA252YH, HP621H and HP646H versions be discarded because grain yield performance was unsatisfactory compared to their respective conventional and transgenic counterparts. The parameters GD and W1000 are more effective for grain yield estimation than NR and NG. It was observed for HP621H that, in addition to a lower grain yield, there was a significant reduction in stem diameter, indicating a possible reduction in lodging tolerance and/or plant breaking when exposed to adverse climatic conditions such as windstorms. For the HPD354H version, the release of the transgenic counterpart HPD354YH is preferentially indicated since the H version had a significant reduction in stem diameter and a possible greater tolerance to lodging and/or plant breaking under the same conditions.  


2016 ◽  
Vol 107 (2) ◽  
pp. 188-199 ◽  
Author(s):  
G.H. Baker ◽  
C.R. Tann

AbstractThe cotton bollworm, Helicoverpa armigera, is a major pest of many agricultural crops in several countries, including Australia. Transgenic cotton, expressing a single Bt toxin, was first used in the 1990s to control H. armigera and other lepidopteran pests. Landscape scale or greater pest suppression has been reported in some countries using this technology. However, a long-term, broad-scale pheromone trapping program for H. armigera in a mixed cropping region in eastern Australia caught more moths during the deployment of single Bt toxin cotton (Ingard®) (1996–2004) than in previous years. This response can be attributed, at least in part, to (1) a precautionary cap (30% of total cotton grown, by area) being applied to Ingard® to restrict the development of Bt resistance in the pest, and (2) during the Ingard® era, cotton production greatly increased (as did that of another host plant, sorghum) and H. armigera (in particular the 3rd and older generations) responded in concert with this increase in host plant availability. However, with the replacement of Ingard® with Bollgard II® cotton (containing two different Bt toxins) in 2005, and recovery of the cotton industry from prevailing drought, H. armigera failed to track increased host-plant supply and moth numbers decreased. Greater toxicity of the two gene product, introduction of no cap on Bt cotton proportion, and an increase in natural enemy abundance are suggested as the most likely mechanisms responsible for the suppression observed.


2005 ◽  
Vol 143 (1) ◽  
pp. 35-41 ◽  
Author(s):  
R. BENNETT ◽  
Y. ISMAEL ◽  
S. MORSE

A study of the commercial growing of different varieties of Bacillus thuringiensis (Bt) cotton compares the performance of growing official and unofficial hybrid varieties of Bt cotton and conventional (non-Bt) hybrids in Gujarat by 622 farmers. Results suggest that the official Bt varieties (MECH 12 and MECH 162) significantly outperform the unofficial varieties. However, unofficial, locally produced Bt hybrids can also perform significantly better than non-Bt hybrids, although second generation (F2) Bt seed appears to have no yield advantage compared to non-Bt hybrids but can save on insecticide use. Although hybrid vigour is reduced, or even lost, with F2 seed the Bt gene still confers some advantage. The F2 seed is regarded as ‘GM’ by the farmers (and is sold as such), even though its yield performance is little better than the non-GM hybrids. The results help to explain why there is so much confusion arising from GM cotton release in India.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
QANDEEL-E-ARSH ◽  
Muhammad Tehseen AZHAR ◽  
Rana Muhammad ATIF ◽  
Mahwish ISRAR ◽  
Azeem Iqbal KHAN ◽  
...  

AbstractThe introduction of genetically modified (GM) cotton in 1996 in the US and its worldwide spread later rejuvenated cotton production in many parts of the world. The evolution is continued since then and currently, the 3rd and fourth generation of same GM cotton is grown in many parts of the world. The GM cotton introduced in 1996 was simple Bt cotton that expressed a single Cry1Ac gene, the later generation carried multiple Cry genes along with the genes controlling herbicide tolerance. Current day GM cotton does not only give stable resistance against lepidopteran insects but also facilitates the farmers to spray broad-spectrum herbicides without harming the crop. The evolution of GM cotton is continued both on the basic and applied side and interventions have been introduced during the last decade. Earlier the cotton transformation was limited to Cocker strains which are getting possible in many other varieties, too. It is successful with both gene gun, and Agrobacterium and inplanta transformation has made it a routine activity. Apart from overexpression studies for various purposes including biotic, abiotic, and quality traits, RNAi and genome editing are explored vigorously. Through this review, we have tried to explore and discuss various interventions for improving transformation protocols, the applications of cotton transformation, and future strategies being developed to get maximum benefits from this technology during the last decade.


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