Developing Bt maize for resource-poor farmers – Recent advances in the IRMA project

Mugo, Stephen; Groote, Hugo De; Bergvinson, David; Mulaa, M.; Songa, J. M.; Gichuki, S.

doi:10.4314/ajfand.v4i13.71814

Cited by 23 publications

(30 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The study findings are consistent with the Mendelian inheritance of a single dominant locus such as the Cry1Ab gene. In addition, these results suggest that in the leaf tissues, expression of the concentration of Bt δ-endotoxins was inherited stably and follows the Mendelian segregation as observed in the crosses of Bt maize events and the non-Bt F 2 generations (Siebert et al, 2009;Mugo et al, 2011). In the contrast analysis, crosses between Bt and nonBt F 1 generations had no significant effect on the mean concentration of Bt δ-endotoxins.…”

Section: Discussionmentioning

confidence: 61%

“…These facilities were designed and developed consistent with international standards and were approved for research on transgenic plants by the Kenya Plant Health Inspectorate Service (KEPHIS) on behalf of the Kenya National Biosafety Committee (NBC). The facilities are for bio-containment and provide an effective means of isolation and prevention of unintended transmission of genetic material (Traynor et al, 2001;Murenga et al, 2004;Mugo et al, 2005;Mugo et al, 2011a).…”

Section: Research Site and Facilitiesmentioning

confidence: 99%

See 1 more Smart Citation

Quantification of Bt δ-endotoxins in leaf tissues of tropical Bt maize populations

Murenga¹,

Danson²,

Mugo³

et al. 2012

Afr. J. Biotechnol.

View full text Add to dashboard Cite

In Kenya, stem borers destroy an estimated 13.5% of farmers' annual maize harvest. Maize transformed using Bacillus thuringiensis (Bt) derived genes controls stem borers without negative effects to humans, livestock or the environment. The effectiveness and sustainability of Bt transgenic technology in the control of stem borers depends on the levels of concentration of the Bt δ-endotoxins in plant tissues. Kenya introduced Bt maize events to test the efficacy of Bt maize in controlling stem borers, and to develop high-yielding and locally adapted Bt maize germplasm for farmers. The objective of this study was to assess under greenhouse conditions the concentration levels of Bt δ-endotoxins in the leaf tissues of the parents, the F 1 , and the F 2:3 populations of tropical maize, as a measure of stability and sustainability. Kenya introduced Bt maize events to test the efficacy of Bt maize in controlling stem borers, and to develop high-yielding and locally adapted Bt maize germplasm for farmers. The objective of this study was to assess under greenhouse conditions the concentration levels of Bt δ-endotoxins in the leaf tissues of the parents, the F1, and the F2:3 populations of tropical maize, as a measure of stability and sustainability. Two public Bt maize lines (Event 216 and Event 223) containing the cry1Ab::ubi gene were crossed with two non-Bt maize inbred lines, CML144 and CML159, to assess how the concentrations of Bt δ-endotoxins are transmitted from parents to F 1 and to F 2 generations. The mean concentration of Bt δ-endotoxins (μg/g) was 4.93 and 4.63 in Events 216 and 223 respectively. As expected, F 1 generations of all the crosses had similar concentrations of Bt δ-endotoxins. However, the F 2 generations showed a spread of concentrations. These findings may imply that genotypes with a higher mean concentration of Bt δ-endotoxins also have a lower level of plant damage traits expressed. In addition, these observations indicate that the cry1Ab gene was dominant and was inherited following the Mendelian segregation and that Events 216 and 223 could be utilized as reliable sources of resistance to stem borers in maize breeding programmes.

show abstract

Section: Discussionmentioning

confidence: 61%

Section: Research Site and Facilitiesmentioning

confidence: 99%

Quantification of Bt δ-endotoxins in leaf tissues of tropical Bt maize populations

Murenga¹,

Danson²,

Mugo³

et al. 2012

Afr. J. Biotechnol.

View full text Add to dashboard Cite

show abstract

“…Especially in Africa, agricultural productivity has not been able to cope with population growth, leading to increased annual imports and food insecurity [1].…”

Section: Introductionmentioning

confidence: 99%

Stimulatory Effect of Hormones, Vitamin C on Growth, Yield and Some Metabolic Activities of Chenopodium quinoa Plants in Egypt

Sofy¹,

Sharaf²,

Fouda³

2016

J Plant Biochem Physiol

View full text Add to dashboard Cite

This research examine the actual growth, yield and certain metabolic activities of quinoa plants in response to foliar treatments with GA 3 50 ppm, JA 20 ppm and Asc. 50 ppm. Plants were grown in natural clay loamy soil conditions and treated with every of the aforementioned treatments. The treated plants showed significant responses in most of the growth and yield characteristics (lengths of shoots and roots, number of branches/plant, number of leaves/ plant, plant biomass and weight of 1000-seed). Also, these treatments caused significant increases in the contents of photosynthetic pigments, soluble carbohydrates, soluble proteins and total phenols content. This was the case during the entire duration of time period of the experiment. Egypt, Seeds of quinoa were sown in plots (4 m width and 10 m length). The plot contained 12 rows, 70 cm apart and the hills were spaced at 20 cm distance. Lit of seeds were sown in each hill, and the stand was later thinned to two plant per hill. Land preparations, agricultural operations followed the normal practices of crops cultivation in the clay loamy soils, the 12 rows divided into 4 groups representing the following treatments: Stimulatory Effect of Hormones1. Tap water (control) 2. Gibberellic acid (50 ppm) 3. Jasmonic acid (20 ppm) Ascorbic acid (50 ppm)The plants of Chenopodium quinoa Willd were treated triple with the above mentioned treatments (as foliage spraying). The first treatment was made when the age of plants was 30 days, while the second treatment was made when the age of plants was 60 days and the third treatment was made when the age of plants was 90 days. The plant samples were collected for analysis when the plants were 40 (Stage I), 70 (Stage II) and 100 (stage III) days old. At the end of the growth season (170 days), analyses of the seeds yielded from the different treatments as well as the control were done. Analysis of soilAnalysis of soil were record Physical properties and chemical properties (Tables 1 and 2). Measurement of soil and growth parametersShoot length (cm), root length (cm), number of leaves per/plant, number of branches per/plant, fresh and dry weights of shoots (g/ plant), fresh and dry weights of roots (g/plant), weight of 1000-seeds (g) were determined at different growth stages. Chemical analysisPhotosynthetic pigments were estimated using the method of Ref.[23] Contents of soluble carbohydrates were measured according to the method of Ref. [24]. Contents of soluble proteins were estimated according to the methods of Ref. [25]. Phenolic compounds were estimated according to the methods of Ref. [26]. total lipids were estimated according to the methods of Ref. [27]. Total saponin were estimated according to the methods of Ref. [28,29]. Statistical methodsAll statistical calculations were done using computer programs. Microsoft excel version 10 and spss (statistica package for the social science version 20.00) statistical program at 0.05 level of probability [30] the One-way ANOVA was presented using percentage, mean ±stand...

show abstract

“…Various successful examples of its application in various crops against pests and diseases were reported (Ordás et al 2009). A greater amount of breeding efforts have been dedicated towards improvement of resistance to maize stem borers in Africa, Europe and Asia (Kumar 1997;Andre 2003;Mugo et al 2005;Sharma et al 2007;Butrón et al 2009;Sandoya et al 2010;Barros et al 2011;Khalifa 2013). Several cycles of recurrent selection have been used to improve maize for resistance against various stem borers species (Ana Paula et al 2013;Dhillon and Gujar 2013;Oloyede-Kamiyo et al 2013).…”

Section: Introductionmentioning

confidence: 99%

Response to S1 recurrent selection for resistance to two stem borers, Busseola fusca and Chilo partellus, in two tropical maize populations

et al. 2015

View full text Add to dashboard Cite

Stem borers, Busseola fusca and Chilo partellus, are among the key devastating lepidopteran insect pests of maize causing grain yield losses. Recurrent selection studies for stem borer resistance in maize are limited. However, maize populations carrying resistance genes to these stem borers have not been exploited fully in breeding programmes. The objective of the study was to separately improve resistance to B. fusca and C. partellus stem borers for two maize populations CML395/MBR C5 Bc and CML444/MBR/MDR C3Bc and therefore grain yield after two cycles of S1 progeny recurrent selection. Cycle 0 and the advanced generations (cycle 1-susceptible, cycle 1-resistant and cycle 2-resistant) were evaluated at three locations in Kenya using a 35 9 12 a-lattice design with 2 replications. The net reductions in cumulative tunneling, number of exit holes and leaf feeding damage scores ranged from 0 to 69 % for both populations after two cycles of selection. In the two populations, each cycle of selection for borer resistance improved grain yield by 0.5-0.8 t ha . Actual net gains in grain yield with reference to cycle 0 were 43 % for population CML395/MBRC5 Bc under B. fusca infestation and 70 % under C. partellus infestation. For population CML444/MBR/MDR C3Bc, the actual net gains in grain yield were 25 % under B. fusca infestation and 36 % under C. partellus infestation. The reductions in the injurious effects attributable to leaf feeding damage, cumulative stem tunneling and number of exit holes contributed towards the 43 and 70 % net genetic gain in grain yield under B. fusca and C. partellus infestation respectively, for both populations. Broad sense heritability (H 2 ) for grain yield ranged from 2 to 98 % in both maize populations. The study showed that two cycles of S1 progeny recurrent selection was effective in accumulating favourable alleles for B. fusca and C. partellus stem borer resistance.

show abstract

Developing Bt maize for resource-poor farmers – Recent advances in the IRMA project

Cited by 23 publications

References 8 publications

Quantification of Bt δ-endotoxins in leaf tissues of tropical Bt maize populations

Quantification of Bt δ-endotoxins in leaf tissues of tropical Bt maize populations

Stimulatory Effect of Hormones, Vitamin C on Growth, Yield and Some Metabolic Activities of Chenopodium quinoa Plants in Egypt

Response to S1 recurrent selection for resistance to two stem borers, Busseola fusca and Chilo partellus, in two tropical maize populations

Contact Info

Product

Resources

About