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Mean number of eggs laid by Busseola fusca moths on maize and different recognized Napier grass varieties in two-choice tests for ovipositional preference.
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Napier grass, Pennisetum purpureum, is used successfully as a trap crop for lepidopterous stem borers in Africa. This paper reports on the evaluation of the suitability of Napier grass varieties as trap crops for Busseola fusca (Lepidoptera: Noctuidae). This was done through oviposition preference tests and evaluation of larval survival on differen...
Contexts in source publication
Context 1
... mean number of egg batches per plant ranged between one and four. There were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Context 2
... were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Context 3
... were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Context 4
... mean number of egg batches per plant ranged between one and four. There were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Context 5
... were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Context 6
... were no significant differences between the number of van den Berg et al.: Oviposition and survival of Busseola fusca on Napier grasses and maizebatches on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3). There were also no significant differences between the total number of eggs laid on maize and Napier plants in either of the two sets of two-choice tests (Tables 2, 3), except for the bioassay with the Pennisetum sp., where significantly more eggs were recorded on maize (P < 0.05) ( Table 2). ...Similar publications
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Citations
... The relatively low levels of larval survival (53.3 and 46.7%) on the two non-Bt maize treatments are typical for B. fusca, which is notoriously difficult to rear under artificial conditions. Strydom et al. [40], Khan et al. [54] and Van den Berg et al. [55] reported similar levels of survival on plants grown in pots in greenhouses. ...
In Africa, the target pests of genetically modified Bt maize are lepidopteran stem borers, notably Busseola fusca (Lepidoptera: Noctuidae). Gene flow between Bt maize hybrids and open pollinated varieties (OPVs) that do not contain the Bt trait is highly likely in areas where both types of maize are cultivated. Consequently, introgression of the cry1Ab transgene into local OPVs will result in unknown patterns of Cry1Ab protein expression in plants during follow up seasons when recycled seed of OPVs is planted. Too low concentrations of Cry protein in such plants may result in selection for resistant alleles and accelerate resistance evolution. The aim of this study was to determine the effects of introgression of the cry1Ab transgene into an OPV, on Cry protein concentration levels and pest survival. Bt transgene introgression was done by crossing a transgenic donor hybrid containing the cry1Ab gene with a non-Bt OPV as well as with a non-Bt near-isogenic hybrid. F1 and F2 crosses as well as back crosses were done yielding 11 genotypes (treatments). Cry1Ab protein concentrations in leaf tissue of these crosses were determined by means of ELISAs. All crosses that contained the transgene had similar or higher Cry1Ab concentrations when compared to the Bt parental hybrid, except for the Bt x OPV F1-cross that had a significantly lower Cry1Ab concentration. Survival B. fusca larvae were evaluated in assays in which larvae were reared for 14 days on whorl leaf tissue of the different treatments. Larval survival did not differ between any of the maize plant treatments which contained the Bt gene. Results suggest that Bt transgene introgression into OPVs may produce plant progenies that express Cry1Ab protein at sufficient concentrations, at last up to the F2 seed, to control B. fusca lar-vae. Resistance evolution is however not only influenced by the frequency of pest individuals that survive exposure to the Cry proteins but also by factors such as genetics of the pest and recipient OPV, pest biology and migration behaviour.
... Napier grass (P. purpureum) and sorghum (Sorghum spp.) (both Poaceae) can control stem borers and are recommended for use as a trap crop around maize fields in Africa (van den Berg 2006a, van den Berg et al. 2006). However, when neither of the above crops could be used due to unsuitable farming conditions, van den Berg (2006b) found vetiver grass (Vetiveria zizanioides [L.] Nash) (both Poaceae) to be a suitable trap crop for stemborers in maize. ...
Trap crops are plants grown along with the main crop in order to manipulate insect behavior to manage the insect pests and are used as a cultural management strategy in several crops. Trap crops also provide habitat to natural enemies and can reduce the need for insecticides and hence reduce the development of insecticide resistance. The attractiveness of the trap crop, the timing of planting, and the space it occupies are major factors to consider before selecting and using a trap crop. The addition of semiochemicals and incorporation of ‘stimulo-deterrent diversion’ can increase the efficiency of trap crops. The important insect pests of cereal crops reported to managed by using trap crops include the wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), on wheat and the stem borers Chilo partellus (Swinhoe) and Busseola fusca (Fuller) on maize and sorghum. Other insect pests such as soil-dwelling wireworms [Agriotes obscurus L., Limonius californicus (Mannerheim) (Coleoptera: Elateridae)] on potatoes and the aphids Schizaphis graminum (Rondani) (Hemiptera: Aphididae), and Rhopalosiphum padi L. on wheat and the brown planthopper Nilaparvata lugens (Stål) on rice are also possible to manage by using trap crops. Cereal crops such as maize and wheat are sometimes themselves used as trap crops, yet there have been only a handful of attempts made to use trap crops in cereal crops. The major limiting factors in using trap crops in cereal crops are environmental conditions, variation in landscape and cultivation practices. Nonetheless, trap crops remain an important tool of integrated pest management, and future studies should work to improve the efficacy, cost efficiency, and availability of alternative trap crops for use in cereal cultivation.
... According to Khan et al. (1997b) some wild hosts are preferred host plants of stem bores and can be utilized as a trap crops in stem borer management strategies. Similarly, oviposition preference studies showed that certain grasses were highly attractive to ovipositing moths, however, survival of the immature stages were generally low (Shanower et al., 1993;Haile & Hofsvang, 2002;Van den Berg et al., 2006). Due to certain antibiosis or antixenosis characteristics, wild grasses and sedges are poor hosts of stem borers as compared to cultivated plants ( Van den Berg, 2017). ...
... purpureum (Ofomata et al., 2000;Khan et al., 2006;Van den Berg et al, 2006). The value of wild habitats as reservoirs of stem borer pest populations has been extensively reviewed by Van den Berg (2017). ...
Lepidopteran stem borers are important field insect pests of maize (Zea mays L.), sorghum (Sorghum bicolor L. (Moench)) and sugarcane (Saccharumofficinarum L.) in Ethiopia. Except for Chilo partellus (Swinhoe) which was accidentally introduced from Asia, all the stem borer pests in Ethiopia are indigenous to the continent. Previous studies indicate that in addition to the pest species, there are non-economic stem borer species among wild host in the natural habitats. Continued habitat fragmentation and degradation due to agricultural activity may result in host range expansion and emergence of “new” stem borer pests. However, previous studies in Ethiopia have focused on the management of stem borer species in cultivated fields. Limited studies have been carried out on the lepidopteran stem borer fauna of the natural habitats in the country. This study was therefore, designed to gather baseline data and information on species diversity and ecology of lepidopteran stem borers in selected vegetation mosaics of cultivated and natural habitats in Ethiopia. Moreover, it provides background information on farmers’ perceptions of stem borer pests and farm management practices.
Interviews were administered to 120 farmers from four maize- and sorghum-growing districts of eastern Ethiopia during 2014 main cropping seasonson management practices of cereal stem borers. Results showed that stem borers were perceived as the most important pests in these crops and resulted an estimated yield loss ranged from 10 to 50%. Due to high cost and non-availability farmers did not apply insecticides for the control of stem borers. Management strategies based on cultural practices were found to be the most promisingcontrol method, even though a considerable proportion of the farmers were not implementing the practices in a way that reduces stem borer damage. The design of appropriate strategies for stem borer management based on farmers’ needs and priorities should be promoted.
The diversity, abundance and interactions of lepidopteran stem borers and their wild host plants were examined in five different vegetation mosaics in Ethiopia. The stem borer species diversity varied among vegetation mosaics and host plants. Forty-four stem borer species belonging to 14 different genera in the families of Noctuidae, Crambidae, Pyralidae and Tortricidae were recorded from 34 wild host plants and through light trap. Among these families, Noctuidae was the highest in species richness with 31 species identified, out of which 15 species and two genera were new to science. Species diversity of stem borers correlates positively with increased plant diversity. Though, the majority of stem borer species had a limited host plant ranges.
Three species of lepidopteran stem borers viz., B. fusca, C. partellus and S. calamistis were found attacking maize and sorghum in eastern Ethiopia. Busseola fusca and C. partellus dominated the stem borer community. The exotic C. partellus was found to be the most damaging in lowland areas while the indigenous B. fuscawas restricted to mid and high-altitude zones. However, the pest status of S. calamistis was low and found in lower and midaltitude zones.
Surveys undertaken in commercial sugarcane estates of Ethiopia verified the presence of two lepidopteran stem borer species on Ethiopian sugarcane. These were the noctuids Sesamia cretica Lederer and Sesamia nonagrioides(Lefèbvre). Both speceis were recorded for the first time on sugarcane in the country. Sesamia cretica was recorded as the only economically important stem borer at Tendaho sugarcane estate, northeastern Ethiopia, while S. nonagrioides was recorded as the only sugarcane borer at Kesem and as the dominant borer at Wonji and Metehara sugar estates in the central part of the country. To investigate the genetic relationships and origin of these newly recorded sugarcane borers in Ethiopia, molecular analyses were conducted on Ethiopian specimens collected from sugarcane and wild hosts with populations in other parts of the African continent and abroad. Phylogeographic study was conducted on populations of S. cretica collected from Ethiopia, Eritrea, Kenya, Cameroon and Iran, using the cytochrome c oxidase subunit I (COI) region of the mitochondrial genome. The phylogenetic analyses separated the specimens into two clades, the Ethiopian and Afro-Asian. The clades diverged long before the domestication of sorghum and introduction of sugarcane in Africa. Analysis of molecular variance indicated significant genetic differentiation among the clades. The observed genetic variation between the clades was further accompanied by restricted gene flow. Geological events such as the Rift Valley and host plant differences seem to have a considerable impact on the genetic diversity in S. cretica. The populations of each clade were collected from a specific host plant. As a result, it was difficult to distinguish the role of each factor (geological events and/or host plant variation) in the genetic divergence of the clades.
Similarly, the genetic relationship of the newly recorded population from Ethiopia and Botswana with the previously reported population of S. nonagrioides was investigated using the COI region of the mitochondrial genome. A total of 113 individuals across the geographic range of the species (twelve countries of Africa and four countries of Palearctic regions) were analyzed and 63 haplotypes were identified. Phylogenetic analysis separated the populations into two clades with no distinct geographic distribution pattern. Moreover, the genetic differentiation was not associated with host plants and geographical distances. Results from the molecular analysis revealed the long-time establishment of S. nonagrioides in Botswana and identified the new sugarcane population from Ethiopia as part of the wild host population in the country. Mass clearing of wild host plants for large scale sugarcane production might be a possible reason for the invasion of sugarcane by S. nonagrioides. The phylogeographic patterns of S. nonagrioides across its geographical scale has likely been shaped by Pleistocene’s climatic oscillations and geographic range expansions from different refugia with secondary contact and admixture.
The study provides insight into the diversity and host plant range of stem borer species in selected localities in Ethiopia. The results showed a great diversity of stem borer species in the study areas. More importantly, this study discusses the ecological interpretation of host plant-stem borer species interactions, particularly in relation to natural habitat disturbances. With the growing threats to natural habitats in response to increasing demands for more agricultural land and predicted adverse effects of climate change, future stem borer pests of cultivated plants may emerge from those listed in this study. Consequently, the newly recorded sugarcane stem borer pests might have expanded their host range to sugarcane in response to habitat modification. The addition of new stem borer species to the already existing pest community would probably complicate the existing stem borer management approaches. Thus, conservation of ecologically important natural habitats has paramount importance to delay host range expansion and/or shift of stem borers to cultivated plants and for provision of ecosystem services. Therefore, it is essential to periodically monitor the dynamics of stem borer communities both in natural and cultivated habitats.
... In many cases, these grasses are dead-end-trap crops. For example, marked preference for oviposition of B. fusca and C. partellus moths has been reported on P. purpureum but it is a very poor larval host for these species (Khan et al. 1997;Ofomata et al. 2000; Van den Berg et al. 2001;Ndemah et al. 2002;Rebe et al. 2004a,b;Mohamed et al. 2004;Khan et al. 2006Khan et al. , 2007Van den Berg 2006;Van den Berg et al. 2006). In Eritrea, Haile and Hofsvang (2002) also reported that although B. fusca preferred certain grass species to maize for oviposition, larval survival on these grasses were very low. ...
Resistance evolution by target pests threatens the sustainability of Bt maize in Africa where insect resistance management (IRM) strategies are faced by unique challenges. The assumptions, on which current IRM strategies for stem borers are based, are not all valid for African maize stem borer species. The high dose-refuge strategy which is used to delay resistance evolution relies heavily on the presence of appropriate refuges (non-Bt plants) where pests are not under selection pressure and where sufficient numbers of Bt-susceptible individuals are produced to mate with possible survivors on the Bt maize crop. Misidentification of stem borer species and inaccurate reporting on wild host plant diversity over the past six decades created the perception that grasses will contribute to IRM strategies for these pests in Africa. Desired characteristics of refuge plants are that they should be good pest hosts, implying that larval survival is high and that it produces sufficient numbers of high-quality moths. Refuge plants should also have large cover abundance in areas where Bt maize is planted. While wild host plants may suffice in IRM strategies for polyphagous pests, this is not the case with stenophagous pests. This review discusses data of ecological studies and stem borer surveys conducted over the past decade and shows that wild host plants are unsuitable for development and survival of sufficient numbers of stem borer individuals. These grasses rather act as dead-end-trap plants and do not comply with refuge requirements of producing 500 susceptible individuals for every one resistant individual that survives on Bt maize.
... This species, however, is uncommon in wild habitats (Sezonlin et al. 2005). In a study on the responsiveness of B. fusca moths to plant odours, the insect showed a clear preference for maize plants in choice tests comparing maize and P. purpureum (Van den Berg et al. 2006;Calatayud 2014a). This preference for cultivated maize over the wild P. purpureum suggests that plant odour may not be the only factor in host location and preference by B. fusca. ...
The host plant range of pests can have important consequences for its evolution, and plays a critical role in the emergence and spread of a new pest outbreak. This study addresses the ecological genetics of the indigenous African maize stem borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae), in an attempt to investigate the evolutionary forces that may be involved in the recent host range expansion and establishment of this species in Ethiopian and southern African sugarcane. We used populations from Ethiopia, Zimbabwe, and South Africa to examine whether the host range expansion patterns shared by the Ethiopian and the southern African populations of B. fusca have evolved independently. Base-pair differences in the cytochrome oxidase I (COI) gene were used to characterize haplotype diversity and phylogenetic relationships. There were seven haplotypes among the 30 sequenced individuals collected on four host plant species from 17 localities in the four countries. Of the seven COI haplotypes identified, the two major ones occurred in both sugarcane and maize. Genetic analyses revealed no detectable genetic differentiation between southern African B. fusca populations from maize and sugarcane (FST = 0.019; P = 0.24). However, there was strong evidence of variation in genetic composition between populations of the pest from different geographic regions (FST = 0.948; P < 0.001). The main implication of these findings is that the B. fusca populations in maize in southern Africa are more likely to shift to sugarcane, suggesting that ecological opportunity is an important factor in host plant range expansion by a pest.
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... First, stem borer moths may be attracted to Napier grass. Although Van den Berg et al. (2006) and Khan et al. (2007) showed that B. fusca moths did lay their eggs on Napier grass, the preference for the grass to maize was not strong and oviposition was largely similar on these two plant species. Attractiveness alone is, therefore, unlikely to have resulted in the efficacy of Napier grass as trap crop for B. fusca in this study. ...
Napier grass, Pennisetum purpureum (Schumach), in combination with intercrops has been used successfully in habitat management for maize stem borers in Africa. The use of Napier grass only as a trap or barrier plant for Chilo partellus (Lepidoptera: Crambidae) and Busseola fusca (Fuller) (Lepidoptera: Noctuidae) was evaluated in this study. Napier grass borders were planted only on two sides of small-scale farmers’ maize fields, since planting of perennial trap crops on all sides of fields hampered mechanical cultivation. C. partellus was the dominant borer species, followed by B. fusca and Sesamia calamistis (Hampson) (Lepidoptera: Noctuidae). Reductions between 0% and 27.4% in the incidence of borer-infested plants were observed on the 16 farms evaluated in this study. The results show that Napier grass as trap/barrier crop suppresses stem borer numbers in maize fields.
... Under laboratory and semi-field conditions however, B. fusca has been reported to lay large numbers of eggs on several varieties of P. purpureum, with the number of eggs laid per variety as well as larval survival being negatively correlated with the number of trichomes present on leaves of these varieties [69]. Busseola fusca has also been reported to infest P. purpureum under field conditions in South Africa [74]. In Kenya, B. fusca is rarely found to infest A. donax and P. purpureum compared to Ethiopia and South Africa, respectively. ...
... This can be due to locally adapted B. fusca populations, which are able to infest those plant species in those countries, though there still exists the possibility that the species have not been properly identified. For example, in Cameroon, follow-up studies and identification of borers by Ndemah et al. [64] showed that the reported frequent occurrence of B. fusca on P. purpureum in earlier studies [62,74] was the result of misidentification of the species. ...
Busseola fusca (Lepidoptera: Noctuidae) is an important pest of maize and sorghum in sub-Saharan Africa. One century after its first description by Fuller in 1901, inaccurate information based on earlier reports are still propagated on its distribution (e.g., absent from the lower altitudes in East Africa) and host plant range (e.g., feeding on a large range of wild grass species). This review provides updated information on the biology, distribution and genetics of B. fusca with emphasis on insect-plant interactions. Related to this, new avenues of stem borer management are proposed.
... The desmodium plant produces volatiles which repel the moths while volatiles produced by the trap plant attract them (Pickett et al., 2007). The emergent larvae from oviposition are trapped by a sticky substance produced by the Napier grass which inhibits the larvae's full development to adulthood (Van den Berg et al., 2006). Further, desmodium roots produce chemical compounds, some of which stimulate Striga germination and others inhibit expected lateral root growth, thereby hindering its parasitic attachment to maize roots ( Tsanuo et al., 2003). ...
Use of farmers as extension agents to disseminate new technologies to others is increasingly being adapted in smallholder farming systems. This paper examined technical efficiency (TE) of farmer teachers in the uptake and dissemination of a ‘push–pull’ technology (PPT) for control of Striga weed and stemborers in Western Kenya. A total sample of 112 farmer teachers (FTs) and 560 follower farmers (FFs) who had adopted the PPT were randomly selected and interviewed between July and August 2007. The farm production constraints significantly reduced with an overall 53% margin following PPT uptake. Overall, there were considerable benefits from training resulting in significant differences in understanding and applying of PPT. The farmers' extension strategy had a significant multiplier effect in increasing PPT uptake. The average TE by FTs was 78% while FFs had 71% suggesting room for improvement. The TE was influenced by farmers' interactions with neighbouring farmers, memberships in local groups, type of farmer, farmer's age, marital status and farmer's level of education. The efficiency can be improved by providing farmers with incentives and training, increasing field demonstrations, providing Desmodium seed and credit for other needed inputs to accelerate PPT transfer.
... Testing the potential host range of invasive insects is important for risk assessment and management before their establishment (Kirichenko et al. 2008;Kenis et al. 2009). The potential host-plant range of insects is commonly tested by measuring behaviours such as foraging (Schuler et al. 2003), settling (Prado & Tjallingii 2007), feeding (Troncoso et al. 2005) and oviposition (Smith & Capinera 2005;van den Berg et al. 2006). Miller & Strickler (1984) defined a host plant as a plant that provides sensory cues, such as visual, olfactory, gustatory and tactile cues, to which the insect responds positively at each phase of the host-finding and acceptance process. ...
... Miller & Strickler (1984) defined a host plant as a plant that provides sensory cues, such as visual, olfactory, gustatory and tactile cues, to which the insect responds positively at each phase of the host-finding and acceptance process. Host specificity of insects is preferably assessed by both choice and no-choice tests (Withers 1997;Kirker et al. 2008), and the choice tests are used to test host-plant preference of insects (Smith & Capinera 2005;van den Berg et al. 2006). Host acceptance behaviour is a key character responsible for host-plant specialisation of phytophagous arthropods (Skoracka et al. 2007). ...
The electrical penetration graph (EPG) technique is being developed for rapid assessment of host range of potential xylem feeding invaders in New Zealand. Stylet penetration behaviours of adult spittle bug Carystoterpa fingens were monitored for 12 h on grape, lemon, apple and kiwifruit plants using EPG. A multiple-choice test of all four plant species was conducted concurrently with the EPG tests for comparison. In EPG tests the longest probing and ingestion periods were recorded on grape and lemon, while the shortest probing and ingestion periods were recorded on apple. Results for kiwifruit were intermediate and not significantly different from the other plant types. In the multiple-choice tests, more insects were found on grape and lemon than on apple and kiwifruit. The similar ranking of the host plants in both multiple-choice and EPG tests suggests that EPG is a valid tool for rapidly assessing host feeding acceptance and preference.
... The green leaf volatiles produced by desmodium repel stemborer moths while those produced by the trap plant attract them (Khan et al., 2000(Khan et al., , 2001Khan and Pickett, 2004;Chamberlain et al., 2006). In addition, Napier grass does not support full stemborer larval development and hence majority of the larvae die before reaching adulthood (Khan et al., 2006a(Khan et al., , 2007aVan den Berg, 2006;Van den Berg et al., 2006). ...
The ‘push–pull’ technology (PPT), developed in Africa, offers effective control of cereal stemborers and Striga weed in maize-based cropping systems. It involves intercropping maize with desmodium, Desmodium uncinatum, with Napier grass, Pennisetum purpureum, planted as border around this intercrop. Desmodium repels the stemborer moths (push) that are subsequently attracted to the Napier grass (pull). Desmodium also suppresses and eliminates Striga. We assessed economic performance of this technology compared to the conventional maize mono- and maize–bean intercropping systems in six districts in western Kenya over 4–7 years. Ten farmers were randomly recruited in each district and each planted three plots representing the three cropping systems. The cost–benefit analyses were carried out, together with the systems’ net returns to land and labour and their discounted net present values (NPV). Maize grain yields and associated gross margins from the PPT system were significantly higher than those in the other two systems. Although the production costs were significantly higher in the PPT than in the two cropping systems in the first cropping year, these reduced to either the same level or significantly lower than in the maize–bean intercrop from the second year onwards in most of the districts. Similarly, the net returns to land and labour with the PPT were significantly higher than with the other two systems. The PPT consistently produced positive NPV when the incremental flows of its benefits compared to those of the two conventional systems were discounted at 10–30%, indicating that PPT is more profitable than the other two systems under realistic production assumptions. PPT is thus a viable option for enhancing productivity and diversification for smallholder farmers who largely depend on limited land resource. Hence, enhancing farmers’ access to less costly planting materials and promoting quality education and training in the use of this knowledge-intensive technology could stimulate its successful adoption.
