The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Zeyaur R. Khan - One of the best experts on this subject based on the ideXlab platform.
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Intercropping Desmodium and maize improves nitrogen and phosphorus availability and performance of maize in Kenya
Field Crops Research, 2021Co-Authors: Pierre Celestin Ndayisaba, Charles A. O. Midega, Shem Kuyah, Peter N. Mwangi, Zeyaur R. KhanAbstract:Abstract Low levels of nitrogen (N) and phosphorus (P) in soils in sub-Saharan Africa (SSA) limit maize (Zea mays) production in smallholder farms. We tested the hypothesis that Desmodium (Desmodium intortum (Mill.) Urb.), a fodder legume, and food legumes commonly grown with maize in Western Kenya avail N and P and improve the performance of maize in intercrops. We measured available N and P in 15 cm topsoil at 4, 8 and 12 weeks after planting (WAP), and corresponding maize shoot weight in three seasons: 2017 long rains (LR), 2017 short rains (SR), and 2018 LR at Thomas Odhiambo Campus of icipe at Mbita Point in western Kenya. Treatments were additive 1:1 maize-legume intercrops; maize-bean (Phaseolus vulgaris L.), maize-cowpea (Vigna unguiculata (L.) Walp.), maize-crotalaria (Crotalaria ochroleuca G. Don), maize-Desmodium, maize-green gram [Vigna radiata (L.) Wilczek] and maize-groundnut (Arachis hypogaea L.), and maize monocrop as a control, replicated four times in a complete randomized design. This experiment was established in 2003 and treatments were repeated every season on the same plot (for 31 seasons up to 2018 LR). At the beginning (year 2003), experimental plots were infested with 100 g of striga seeds per 250 g soil. Across the three last seasons corresponding to this study, we observed an increase in available N in maize-Desmodium plots compared to maize monocrop plots. Available P measured at 4, 8 and 12 WAP in 2017 SR and at 4 WAP in 2018 LR was higher in maize-Desmodium than in maize monocrop at the same sampling times (P
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isolation and identification of Desmodium root exudates from drought tolerant species used as intercrops against striga hermonthica
Phytochemistry, 2015Co-Authors: Antony M Hooper, Charles A. O. Midega, J. A. Pickett, John C Caulfield, B Hao, Zeyaur R. KhanAbstract:Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition.
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achieving food security for one million sub saharan african poor through push pull innovation by 2020
Philosophical Transactions of the Royal Society B, 2014Co-Authors: Zeyaur R. Khan, Charles A. O. Midega, Jimmy Pittchar, A W Murage, Michael Alexander Birkett, Toby J. A. Bruce, J. A. PickettAbstract:Food insecurity is a chronic problem in Africa and is likely to worsen with climate change and population growth. It is largely due to poor yields of the cereal crops caused by factors including stemborer pests, striga weeds and degraded soils. A platform technology, ‘push–pull’, based on locally available companion plants, effectively addresses these constraints resulting in substantial grain yield increases. It involves intercropping cereal crops with a forage legume, Desmodium, and planting Napier grass as a border crop. Desmodium repels stemborer moths (push), and attracts their natural enemies, while Napier grass attracts them (pull). Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. Both companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers’ income sources. To extend these benefits to drier areas and ensure long-term sustainability of the technology in view of climate change, drought-tolerant trap and intercrop plants are being identified. Studies show that the locally commercial brachiaria cv mulato (trap crop) and greenleaf Desmodium (intercrop) can tolerate long droughts. New on-farm field trials show that using these two companion crops in adapted push–pull technology provides effective control of stemborers and striga weeds, resulting in significant grain yield increases. Effective multi-level partnerships have been established with national agricultural research and extension systems, non-governmental organizations and other stakeholders to enhance dissemination of the technology with a goal of reaching one million farm households in the region by 2020. These will be supported by an efficient Desmodium seed production and distribution system in eastern Africa, relevant policies and stakeholder training and capacity development.
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cumulative effects and economic benefits of intercropping maize with food legumes on striga hermonthica infestation
Field Crops Research, 2014Co-Authors: Charles A. O. Midega, Jimmy Pittchar, J. A. Pickett, Toby J. A. Bruce, Daisy Salifu, Zeyaur R. KhanAbstract:The parasitic weed Striga hermonthica, commonly known as striga, is a major biotic constraint to maize production in sub-Saharan Africa (SSA) where it causes serious food insecurity and poverty in smallholder farming communities. We previously discovered an effective control method for it involving intercropping cereals with fodder legumes in the genus Desmodium, commonly known as Desmodium. The objectives of the current study were to evaluate cumulative effects of intercropping maize with the commonly grown food legumes on striga infestation, and to establish any economic benefits of the same. Treatments comprised maize plots planted in monocrop stands or intercropped with five different food legume species or Desmodium. Intercropping maize with Desmodium gave the most consistent and significant suppression of striga. Out of the food legume intercrops, only crotalaria, groundnut and greengram intercrops had significantly lower striga counts and only in some of the cropping seasons. Grain yields were consistently and significantly higher with Desmodium intercrop, although they were also increased with food legume intercrops compared to maize monocrop, thus confirming superiority of intercropping with legumes over maize monocrop. Although production costs in terms of total labor and variable costs were significantly higher for the intercrops than for the maize monocrop, total revenue and net benefits were significantly higher in the former, especially for Desmodium. The Desmodium intercrop gave the highest economic benefits followed by crotalaria and greengram intercrops. These results confirmed the effectiveness of Desmodium in suppressing striga and improving yields and economic returns to smallholder farmers. They also showed that it is profitable to invest in food legume intercrop systems, especially the crotalaria and greengram systems, and indicate that intensifying maize cropping systems through integration of these food legumes in combination with other approaches can contribute to an integrated management of striga and provide a more sustainable and profitable productive system to smallholder farmers.
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The impact of Desmodium spp. and cutting regimes on the agronomic and economic performance of Desmodium–maize intercropping system in western Kenya
Field Crops Research, 2012Co-Authors: M. N. Kifuko-koech, Zeyaur R. Khan, John A. Pickett, P. Pypers, C. O. Othieno, A. K. Kipkoech, J. R. Okalebo, B. VanlauweAbstract:Low soil fertility, stemborers (particularly, Chilo partellus) and Striga weeds (Striga hermonthica and Striga asiatica) are major limitations to production of maize in western Kenya. The “Push–Pull” technology (“PPT”) has been described as an appropriate innovative technology capable of addressing these constraints. The technology involves intercropping maize with Desmodium and planting Napier grass (Pennisetum purpureum) around the intercrop, but in the current study a modified PPT was used and Napier grass was not included. Field trials were conducted in two locations in western Kenya during 4 subsequent seasons to test the hypothesis that maize yield, the degree of Striga suppression and economic benefits of intercropping maize with Desmodium are affected by: (i) the related biomass production by different Desmodium species and (ii) the cutting regime of the Desmodium. Maize was intercropped with Desmodium uncinatum (Jacq.) DC, cv Silverleaf or Desmodium intortum (Mill.) Urb. cv Greenleaf, and treatments with sole maize (with and without urea) were included for comparison. To eliminate phosphorus (P) deficiency, all treatments received basal P. The first two Desmodium cutting events were fixed at land preparation i.e. at the start of every season, and 4 weeks later, following the recommended practice, while the third cutting was varied and conducted at 9, 12 or 18 weeks after planting maize. Maize yield in the Desmodium–maize intercropping system was only higher than sole maize without urea from the third season. This implies that when P is not limiting inclusion of Desmodium spp. into the maize cropping system would provide a substitute for inorganic N fertilizers to enhance crop growth and yield after Desmodium becomes well established. Cumulative maize grain yield over the four seasons with the D. intortum and D. uncinatum intercrops were 6.3 and 7.0, and 10.9 and 11.6 t ha−1 in Busia and Siaya, respectively, and significantly higher than or comparable to a maize monocrop (5.8 and 11.8 t ha−1). Average net benefits from Desmodium intercropping over the four seasons were increased by 1290 and 918$ ha−1 relative to the maize monocrop in Busia and Siaya, respectively. Biomass yields were significantly higher for D. intortum than for D. uncinatum. Varying the time of the third Desmodium cutting had little effect on Desmodium biomass yields or maize grain yields in Busia, while in Siaya, D. intortum biomass yields were highest when cut at 12 weeks after planting. In the Desmodium intercropping systems, Striga counts were reduced by 95% in Busia and by 65–90% in Siaya with higher reductions when Desmodium was cut at 18 weeks after planting. In summary, the use of PPT provides robust and high economic benefits to smallholder farmers in western Kenya. The use of D. uncinatum with the third cutting at 18 weeks after planting is recommended, but can be modified according to the need for fodder without much effect on maize yield or revenue.
J. A. Pickett - One of the best experts on this subject based on the ideXlab platform.
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isolation and identification of Desmodium root exudates from drought tolerant species used as intercrops against striga hermonthica
Phytochemistry, 2015Co-Authors: Antony M Hooper, Charles A. O. Midega, J. A. Pickett, John C Caulfield, B Hao, Zeyaur R. KhanAbstract:Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition.
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achieving food security for one million sub saharan african poor through push pull innovation by 2020
Philosophical Transactions of the Royal Society B, 2014Co-Authors: Zeyaur R. Khan, Charles A. O. Midega, Jimmy Pittchar, A W Murage, Michael Alexander Birkett, Toby J. A. Bruce, J. A. PickettAbstract:Food insecurity is a chronic problem in Africa and is likely to worsen with climate change and population growth. It is largely due to poor yields of the cereal crops caused by factors including stemborer pests, striga weeds and degraded soils. A platform technology, ‘push–pull’, based on locally available companion plants, effectively addresses these constraints resulting in substantial grain yield increases. It involves intercropping cereal crops with a forage legume, Desmodium, and planting Napier grass as a border crop. Desmodium repels stemborer moths (push), and attracts their natural enemies, while Napier grass attracts them (pull). Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. Both companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers’ income sources. To extend these benefits to drier areas and ensure long-term sustainability of the technology in view of climate change, drought-tolerant trap and intercrop plants are being identified. Studies show that the locally commercial brachiaria cv mulato (trap crop) and greenleaf Desmodium (intercrop) can tolerate long droughts. New on-farm field trials show that using these two companion crops in adapted push–pull technology provides effective control of stemborers and striga weeds, resulting in significant grain yield increases. Effective multi-level partnerships have been established with national agricultural research and extension systems, non-governmental organizations and other stakeholders to enhance dissemination of the technology with a goal of reaching one million farm households in the region by 2020. These will be supported by an efficient Desmodium seed production and distribution system in eastern Africa, relevant policies and stakeholder training and capacity development.
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cumulative effects and economic benefits of intercropping maize with food legumes on striga hermonthica infestation
Field Crops Research, 2014Co-Authors: Charles A. O. Midega, Jimmy Pittchar, J. A. Pickett, Toby J. A. Bruce, Daisy Salifu, Zeyaur R. KhanAbstract:The parasitic weed Striga hermonthica, commonly known as striga, is a major biotic constraint to maize production in sub-Saharan Africa (SSA) where it causes serious food insecurity and poverty in smallholder farming communities. We previously discovered an effective control method for it involving intercropping cereals with fodder legumes in the genus Desmodium, commonly known as Desmodium. The objectives of the current study were to evaluate cumulative effects of intercropping maize with the commonly grown food legumes on striga infestation, and to establish any economic benefits of the same. Treatments comprised maize plots planted in monocrop stands or intercropped with five different food legume species or Desmodium. Intercropping maize with Desmodium gave the most consistent and significant suppression of striga. Out of the food legume intercrops, only crotalaria, groundnut and greengram intercrops had significantly lower striga counts and only in some of the cropping seasons. Grain yields were consistently and significantly higher with Desmodium intercrop, although they were also increased with food legume intercrops compared to maize monocrop, thus confirming superiority of intercropping with legumes over maize monocrop. Although production costs in terms of total labor and variable costs were significantly higher for the intercrops than for the maize monocrop, total revenue and net benefits were significantly higher in the former, especially for Desmodium. The Desmodium intercrop gave the highest economic benefits followed by crotalaria and greengram intercrops. These results confirmed the effectiveness of Desmodium in suppressing striga and improving yields and economic returns to smallholder farmers. They also showed that it is profitable to invest in food legume intercrop systems, especially the crotalaria and greengram systems, and indicate that intensifying maize cropping systems through integration of these food legumes in combination with other approaches can contribute to an integrated management of striga and provide a more sustainable and profitable productive system to smallholder farmers.
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push pull technology a conservation agriculture approach for integrated management of insect pests weeds and soil health in africa
International Journal of Agricultural Sustainability, 2011Co-Authors: Zeyaur R. Khan, Charles A. O. Midega, Jimmy Pittchar, J. A. Pickett, Toby J. A. BruceAbstract:Push—pull technology (www.push-pull.net) is based on a novel cropping system developed by the International Centre of Insect Physiology and Ecology, Rothamsted Research (UK) and national partners for integrated pest, weed and soil management in cereal—livestock farming systems. Stemborers are attracted to Napier grass (Pennisetum purpureum), a trap plant (pull), and are repelled from the main cereal crop using a repellent legume intercrop (push), Desmodium (Desmodium spp.). Desmodium root exudates effectively control the parasitic striga weed by causing abortive germination. Desmodium also improves soil fertility through nitrogen fixation, natural mulching, improved biomass and control of erosion. Both companion plants provide high value animal fodder, facilitating milk production and diversifying farmers' income sources. The technology is appropriate to smallholder mixed cropping systems in Africa. It effectively addresses major production constraints, increases maize yields from below 1 to 3.5t/ha, and ...
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Effect of varying Desmodium and maize harvesting regimes on their yields and growth attributes within the "push-pull" intercropping systems in Western Kenya.
2010Co-Authors: M. N. Koech, J. A. Pickett, P. Pypers, C. O. Othieno, Z. Khan, B. Vanlauwe, J. R. Okalebo, E. Adipala, G. Tusiime, J. G. M. MajaliwaAbstract:Resume Research Application Summary This study tested the hypothesis that inclusion of Desmodium spp. into maize cropping system under the push-pull technology enhanced crop growth and yield. Field trials were conducted in Siaya and Busia districts of western Kenya with the following treatments: two Desmodium spp (Desmodium uncinatum Jacq and Desmodium intortum Urb.) intercropped with maize, sole maize with urea (90 kg N /ha) and sole maize without urea and three Desmodium harvesting regimes (9, 12 and 17 weeks after planting maize- WAPM). Maize shoots/grain harvesting and sampling for mineral N (up to 120 cm) was conducted at 9, 10, 12, 13, 15 and 17 WAMP. Soils from both sites were acidic (pH < 5.3), had low N (
Charles A. O. Midega - One of the best experts on this subject based on the ideXlab platform.
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Intercropping Desmodium and maize improves nitrogen and phosphorus availability and performance of maize in Kenya
Field Crops Research, 2021Co-Authors: Pierre Celestin Ndayisaba, Charles A. O. Midega, Shem Kuyah, Peter N. Mwangi, Zeyaur R. KhanAbstract:Abstract Low levels of nitrogen (N) and phosphorus (P) in soils in sub-Saharan Africa (SSA) limit maize (Zea mays) production in smallholder farms. We tested the hypothesis that Desmodium (Desmodium intortum (Mill.) Urb.), a fodder legume, and food legumes commonly grown with maize in Western Kenya avail N and P and improve the performance of maize in intercrops. We measured available N and P in 15 cm topsoil at 4, 8 and 12 weeks after planting (WAP), and corresponding maize shoot weight in three seasons: 2017 long rains (LR), 2017 short rains (SR), and 2018 LR at Thomas Odhiambo Campus of icipe at Mbita Point in western Kenya. Treatments were additive 1:1 maize-legume intercrops; maize-bean (Phaseolus vulgaris L.), maize-cowpea (Vigna unguiculata (L.) Walp.), maize-crotalaria (Crotalaria ochroleuca G. Don), maize-Desmodium, maize-green gram [Vigna radiata (L.) Wilczek] and maize-groundnut (Arachis hypogaea L.), and maize monocrop as a control, replicated four times in a complete randomized design. This experiment was established in 2003 and treatments were repeated every season on the same plot (for 31 seasons up to 2018 LR). At the beginning (year 2003), experimental plots were infested with 100 g of striga seeds per 250 g soil. Across the three last seasons corresponding to this study, we observed an increase in available N in maize-Desmodium plots compared to maize monocrop plots. Available P measured at 4, 8 and 12 WAP in 2017 SR and at 4 WAP in 2018 LR was higher in maize-Desmodium than in maize monocrop at the same sampling times (P
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isolation and identification of Desmodium root exudates from drought tolerant species used as intercrops against striga hermonthica
Phytochemistry, 2015Co-Authors: Antony M Hooper, Charles A. O. Midega, J. A. Pickett, John C Caulfield, B Hao, Zeyaur R. KhanAbstract:Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition.
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achieving food security for one million sub saharan african poor through push pull innovation by 2020
Philosophical Transactions of the Royal Society B, 2014Co-Authors: Zeyaur R. Khan, Charles A. O. Midega, Jimmy Pittchar, A W Murage, Michael Alexander Birkett, Toby J. A. Bruce, J. A. PickettAbstract:Food insecurity is a chronic problem in Africa and is likely to worsen with climate change and population growth. It is largely due to poor yields of the cereal crops caused by factors including stemborer pests, striga weeds and degraded soils. A platform technology, ‘push–pull’, based on locally available companion plants, effectively addresses these constraints resulting in substantial grain yield increases. It involves intercropping cereal crops with a forage legume, Desmodium, and planting Napier grass as a border crop. Desmodium repels stemborer moths (push), and attracts their natural enemies, while Napier grass attracts them (pull). Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. Both companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers’ income sources. To extend these benefits to drier areas and ensure long-term sustainability of the technology in view of climate change, drought-tolerant trap and intercrop plants are being identified. Studies show that the locally commercial brachiaria cv mulato (trap crop) and greenleaf Desmodium (intercrop) can tolerate long droughts. New on-farm field trials show that using these two companion crops in adapted push–pull technology provides effective control of stemborers and striga weeds, resulting in significant grain yield increases. Effective multi-level partnerships have been established with national agricultural research and extension systems, non-governmental organizations and other stakeholders to enhance dissemination of the technology with a goal of reaching one million farm households in the region by 2020. These will be supported by an efficient Desmodium seed production and distribution system in eastern Africa, relevant policies and stakeholder training and capacity development.
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cumulative effects and economic benefits of intercropping maize with food legumes on striga hermonthica infestation
Field Crops Research, 2014Co-Authors: Charles A. O. Midega, Jimmy Pittchar, J. A. Pickett, Toby J. A. Bruce, Daisy Salifu, Zeyaur R. KhanAbstract:The parasitic weed Striga hermonthica, commonly known as striga, is a major biotic constraint to maize production in sub-Saharan Africa (SSA) where it causes serious food insecurity and poverty in smallholder farming communities. We previously discovered an effective control method for it involving intercropping cereals with fodder legumes in the genus Desmodium, commonly known as Desmodium. The objectives of the current study were to evaluate cumulative effects of intercropping maize with the commonly grown food legumes on striga infestation, and to establish any economic benefits of the same. Treatments comprised maize plots planted in monocrop stands or intercropped with five different food legume species or Desmodium. Intercropping maize with Desmodium gave the most consistent and significant suppression of striga. Out of the food legume intercrops, only crotalaria, groundnut and greengram intercrops had significantly lower striga counts and only in some of the cropping seasons. Grain yields were consistently and significantly higher with Desmodium intercrop, although they were also increased with food legume intercrops compared to maize monocrop, thus confirming superiority of intercropping with legumes over maize monocrop. Although production costs in terms of total labor and variable costs were significantly higher for the intercrops than for the maize monocrop, total revenue and net benefits were significantly higher in the former, especially for Desmodium. The Desmodium intercrop gave the highest economic benefits followed by crotalaria and greengram intercrops. These results confirmed the effectiveness of Desmodium in suppressing striga and improving yields and economic returns to smallholder farmers. They also showed that it is profitable to invest in food legume intercrop systems, especially the crotalaria and greengram systems, and indicate that intensifying maize cropping systems through integration of these food legumes in combination with other approaches can contribute to an integrated management of striga and provide a more sustainable and profitable productive system to smallholder farmers.
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push pull technology a conservation agriculture approach for integrated management of insect pests weeds and soil health in africa
International Journal of Agricultural Sustainability, 2011Co-Authors: Zeyaur R. Khan, Charles A. O. Midega, Jimmy Pittchar, J. A. Pickett, Toby J. A. BruceAbstract:Push—pull technology (www.push-pull.net) is based on a novel cropping system developed by the International Centre of Insect Physiology and Ecology, Rothamsted Research (UK) and national partners for integrated pest, weed and soil management in cereal—livestock farming systems. Stemborers are attracted to Napier grass (Pennisetum purpureum), a trap plant (pull), and are repelled from the main cereal crop using a repellent legume intercrop (push), Desmodium (Desmodium spp.). Desmodium root exudates effectively control the parasitic striga weed by causing abortive germination. Desmodium also improves soil fertility through nitrogen fixation, natural mulching, improved biomass and control of erosion. Both companion plants provide high value animal fodder, facilitating milk production and diversifying farmers' income sources. The technology is appropriate to smallholder mixed cropping systems in Africa. It effectively addresses major production constraints, increases maize yields from below 1 to 3.5t/ha, and ...
B. Vanlauwe - One of the best experts on this subject based on the ideXlab platform.
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The impact of Desmodium spp. and cutting regimes on the agronomic and economic performance of Desmodium–maize intercropping system in western Kenya
Field Crops Research, 2012Co-Authors: M. N. Kifuko-koech, Zeyaur R. Khan, John A. Pickett, P. Pypers, C. O. Othieno, A. K. Kipkoech, J. R. Okalebo, B. VanlauweAbstract:Low soil fertility, stemborers (particularly, Chilo partellus) and Striga weeds (Striga hermonthica and Striga asiatica) are major limitations to production of maize in western Kenya. The “Push–Pull” technology (“PPT”) has been described as an appropriate innovative technology capable of addressing these constraints. The technology involves intercropping maize with Desmodium and planting Napier grass (Pennisetum purpureum) around the intercrop, but in the current study a modified PPT was used and Napier grass was not included. Field trials were conducted in two locations in western Kenya during 4 subsequent seasons to test the hypothesis that maize yield, the degree of Striga suppression and economic benefits of intercropping maize with Desmodium are affected by: (i) the related biomass production by different Desmodium species and (ii) the cutting regime of the Desmodium. Maize was intercropped with Desmodium uncinatum (Jacq.) DC, cv Silverleaf or Desmodium intortum (Mill.) Urb. cv Greenleaf, and treatments with sole maize (with and without urea) were included for comparison. To eliminate phosphorus (P) deficiency, all treatments received basal P. The first two Desmodium cutting events were fixed at land preparation i.e. at the start of every season, and 4 weeks later, following the recommended practice, while the third cutting was varied and conducted at 9, 12 or 18 weeks after planting maize. Maize yield in the Desmodium–maize intercropping system was only higher than sole maize without urea from the third season. This implies that when P is not limiting inclusion of Desmodium spp. into the maize cropping system would provide a substitute for inorganic N fertilizers to enhance crop growth and yield after Desmodium becomes well established. Cumulative maize grain yield over the four seasons with the D. intortum and D. uncinatum intercrops were 6.3 and 7.0, and 10.9 and 11.6 t ha−1 in Busia and Siaya, respectively, and significantly higher than or comparable to a maize monocrop (5.8 and 11.8 t ha−1). Average net benefits from Desmodium intercropping over the four seasons were increased by 1290 and 918$ ha−1 relative to the maize monocrop in Busia and Siaya, respectively. Biomass yields were significantly higher for D. intortum than for D. uncinatum. Varying the time of the third Desmodium cutting had little effect on Desmodium biomass yields or maize grain yields in Busia, while in Siaya, D. intortum biomass yields were highest when cut at 12 weeks after planting. In the Desmodium intercropping systems, Striga counts were reduced by 95% in Busia and by 65–90% in Siaya with higher reductions when Desmodium was cut at 18 weeks after planting. In summary, the use of PPT provides robust and high economic benefits to smallholder farmers in western Kenya. The use of D. uncinatum with the third cutting at 18 weeks after planting is recommended, but can be modified according to the need for fodder without much effect on maize yield or revenue.
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Economic returns of varying Desmodium trimming regimes in "Push-Pull" intercropping system in western Kenya.
2011Co-Authors: M. N. Koech, P. Pypers, R. Okalebo, C. O. Othieno, Z. Khan, J. Picket, A. K. Kipkoech, B. Vanlauwe, J. S. Tenywa, G. TaulyaAbstract:Push-Pull technology (PPT), which involves intercropping of maize (Zea mays) with Desmodium and planting Napier grass (Pennisetum purpureum) around the intercrop, has been described as an innovative technology capable of replenishing nitrogen, eliminating stemborer and Striga in western Kenya. This study evaluated the agronomic and economic performance of varying trimming regimes of two Desmodium varieties, Desmodium uncinatum Jacq and Desmodium intortum Urb in a PPT. On-farm trials were carried out over four consecutive seasons in Busia and Siaya sites of western Kenya. The tested treatments included three cropping systems namely; mono maize with urea (90 kg N ha-1), mono-maize without urea, maize intercropped with two Desmodium spp. and three Desmodium trimming regimes namely; 9, 12 and 18 weeks after planting maize. To eliminate phosphorus (P) deficiency, all treatments received basal P fertiliser. Desmodium trimming regimes had a small impact on maize grain yields and net present value (NPV). Intercropping Desmodium spp. with maize led to increase in maize grain yield over to mono-maize but this occurred after the system was well established. This implies that when P is not limiting inclusion of Desmodium spp. into maize cropping system would provide a substitute for inorganic N fertilisers to enhance crop growth and yield only after Desmodium becomes well established. This is an indication that PPT can enhance overall household income through improving maize and enabling diversification of complementary agricultural enterprises.
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Effect of varying Desmodium and maize harvesting regimes on their yields and growth attributes within the "push-pull" intercropping systems in Western Kenya.
2010Co-Authors: M. N. Koech, J. A. Pickett, P. Pypers, C. O. Othieno, Z. Khan, B. Vanlauwe, J. R. Okalebo, E. Adipala, G. Tusiime, J. G. M. MajaliwaAbstract:Resume Research Application Summary This study tested the hypothesis that inclusion of Desmodium spp. into maize cropping system under the push-pull technology enhanced crop growth and yield. Field trials were conducted in Siaya and Busia districts of western Kenya with the following treatments: two Desmodium spp (Desmodium uncinatum Jacq and Desmodium intortum Urb.) intercropped with maize, sole maize with urea (90 kg N /ha) and sole maize without urea and three Desmodium harvesting regimes (9, 12 and 17 weeks after planting maize- WAPM). Maize shoots/grain harvesting and sampling for mineral N (up to 120 cm) was conducted at 9, 10, 12, 13, 15 and 17 WAMP. Soils from both sites were acidic (pH < 5.3), had low N (
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Farmers' knowledge and perceptions of blister beetles, Hycleus spp. (Coleoptera: Meloidae), as pest herbivores of Desmodium legumes in western Kenya
International Journal of Pest Management, 2012Co-Authors: Lefulesele N. Lebesa, Zeyaur R. Khan, Ahmed Hassanali, Toby J. A. Bruce, Kerstin Krüger, John A. PickettAbstract:A survey was undertaken to determine the pest status of herbivorous blister beetles, Hycleus spp., in western Kenya where they attack crops such as Desmodium spp., other leguminous plants and sweetpotato. Desmodium spp. are important intercrops in the ‘push–pull’’ strategy adopted for Striga and stemborer control in maize and sorghum. Production of Desmodium seed is adversely affected by blister beetles, which feed on the flowers and negatively affect seed setting. To assess farmers’ knowledge and perceptions of Hycleus spp. as pests, a questionnaire survey was conducted in three sites in Bungoma district, western Kenya, in 2007. The survey was followed by field sampling of Desmodium spp. and sweetpotato to compare the results with the responses received from farmers. Hycleus spp. were mentioned by 75% of the respondents as major pests of Desmodium spp. During field sampling Hycleus spp. comprised 70% of the insect pests collected. According to farmers, blister beetles were more abundant on Desmodium than on sweetpotato. However, field sampling revealed that differences in beetle abundance on the two crops were not consistent across different sites, suggesting that these crops may function as alternative hosts. The study provides baseline information for the development of a management strategy for blister beetles.
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integration of edible beans phaseolus vulgaris l into the push pull technology developed for stemborer and striga control in maize based cropping systems
Crop Protection, 2009Co-Authors: Zeyaur R. Khan, Ahmed Hassanali, Charles A. O. Midega, David M. Amudavi, Jimmy Pittchar, Japhether M. Wanyama, J. A. PickettAbstract:Smallholder farming systems in eastern Africa are characterized by cereal/edible legume intercrops in fields severely constrained by parasitic weed, Striga hermonthica, cereal stemborers and declining soil fertility. The push–pull technology concurrently addresses these constraints. It involves intercropping maize with stemborer repellent fodder legume, Desmodium spp. (push), with an attractant crop, Napier grass, Pennisetum purpureum (pull), planted around this intercrop, thus making it difficult to interplant edible legumes. We assessed farmers’ practice and perceptions on intercropping and willingness to integrate beans in their push–pull plots from a sample of 300 farmers in six districts in western Kenya. All the respondents traditionally intercropped maize with beans, planted either between the rows of maize, in the same holes with maize or in between maize plants within a row. The majority (92%) were willing to integrate beans in their push–pull plots. We, therefore, evaluated effects of integrating beans in the maize–Desmodium intercrops. Treatments comprised a maize monocrop, maize–bean intercrop and three maize–Desmodium intercrops, two of which were integrated with beans, either in the same holes with maize or in between maize plants in a row (bean integration plots). On-farm trials were similarly established among 56 farmers in four districts in western Kenya to assess the two integration methods. S. hermonthica counts and stemborer damage to maize were significantly lower and maize yields significantly higher in the maize–Desmodium and bean integration plots than in the other systems. Overall, integration of beans in the maize–Desmodium intercrops and the planting arrangement did not compromise the S. hermonthica and stemborer control efficacy of Desmodium. Integration of beans significantly increased labour and total variable costs, with these being significantly higher in plots with both crops in different holes than in the same hole. Total revenue, gross benefits and benefit cost ratios did not significantly differ between the bean integration and maize–Desmodium intercrops. Furthermore, these parameters were for most part not affected by the planting arrangements, both on-station and on-farm. These results show that integration of beans in the maize–Desmodium and indeed push– pull technology while guaranteeing an additional crop, a protein source, to the farmers does not compromise the observed benefits of the technology but yields same economic benefits. Where labour is easily available, farmers are, however, advised to plant maize and beans in separate holes to avoid the risk of competition for moisture and nutrients where these might be limiting.
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new genetic opportunities from legume intercrops for controlling striga spp parasitic weeds
Pest Management Science, 2009Co-Authors: Antony M Hooper, Zeyaur R. Khan, Ahmed Hassanali, Keith Chamberlain, J. A. PickettAbstract:In smallholder farming in East Africa, intercropping of maize with the cattle forage legume, Desmodium uncinatum Jacq., prevents parasitism by Striga hermonthica (Del.) Benth. (witchweed) through an allelopathic mechanism. Isoschaftoside, a diC-glycosylflavone, isolated from the root extract and root exudate of Desmodium, interferes with in vitro radicle development of germinated Striga. The biosynthetic pathway of this class of compound is already mostly present in edible legumes and in cereals, so characterisation of the enzyme and genes that control C-glycosylflavone biosynthesis has the potential to create this protection mechanism in other agriculturally important plants.
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assessment of different legumes for the control of striga hermonthica in maize and sorghum
Crop Science, 2007Co-Authors: Zeyaur R. Khan, Ahmed Hassanali, Charles A. O. Midega, J. A. Pickett, Lester J. WadhamsAbstract:The witchweed, Striga hermonthica (Del.) Benth., is a major constraint to maize (Zea mays L.) and sorghum [Sorghum bicolor (L.) Moench] production in sub-Saharan Africa. Intercropping maize and sorghum with Desmodium (Desmodium spp.) effectively controls Striga and enhances grain yields. Studies were thus conducted to assess the potential role of intercropping maize and sorghum with different food legumes for control of Striga. Seasonal Striga counts in the intercrops, other than greenleaf Desmodium where the counts consistently remained close to zero, were generally not signifi cantly different from those in the control in both crops. A pooled analysis across seasons, however, showed that intercropping sorghum with cowpea [Vigna ungui culata (L.) Walp.], greengram [Vigna radiata (L.) Wilczek], and crotalaria (Crotalaria ochroleuca G. Don), and maize with crotalaria signifi cantly reduced Striga populations. Within-season analysis showed that it was only the greenleaf Desmodium intercrop that maintained signifi cantly enhanced grain yields relative to the control. On the other hand, multiseason analysis showed that it was only the crotalaria, cowpea, and greenleaf Desmodium intercrops in maize and greenleaf Desmodium intercrop in sorghum that signifi cantly enhanced grain yields. These results indicate that intercropping sorghum with cowpea, greengram, or crotalaria and maize with crotalaria could be combined with other cultural methods for a sustainable control of S. hermonthica.
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Combined control of Striga hermonthica and stemborers by maize-Desmodium spp. intercrops
Crop Protection, 2006Co-Authors: Zeyaur R. Khan, Ahmed Hassanali, Lester J. Wadhams, John A. Pickett, Charles A. O. MidegaAbstract:The African witchweed (Striga spp.) and lepidopteran stemborers are two major biotic constraints to the efficient production of maize in sub-Saharan Africa. Previous studies had shown the value of intercropping maize with Desmodium uncinatum in the control of both pests. The current study was conducted to assess the potential role of other Desmodium spp., adapted to different agro-ecologies, in combined control of both pests in Kenya. Treatments consisted of intercropped plots of a Striga hermonthica- and stemborer-susceptible maize variety and one Desmodium sp. or cowpea, with a maize monocrop plot included as a control. S. hermonthica counts and stemborer damage to maize plants were significantly reduced in maize–Desmodium intercrops (by up to 99.2% and 74.7%, respectively) than in a maize monocrop and a maize–cowpea intercrop. Similarly, maize plant height and grain yields were significantly higher (by up to 103.2% and 511.1%, respectively) in maize–Desmodium intercrops than in maize monocrops or maize–cowpea intercrops. These results confirmed earlier findings that intercropping maize with D. uncinatum effectively suppressed S. hermonthica and stemborer infestations in maize resulting in higher crop yields. They also demonstrate that the other Desmodium spp. assessed in the current study have similar effects as D. uncinatum, indicating comparable phytochemical and other relevant attributes in these species. Overall results indicate the suitability of the Desmodium spp. for the control of both S. hermonthica and stemborers in maize. r 2006 Elsevier Ltd. All rights reserved.