Yield Effects of Tissue Culture Bananas in Kenya: Accounting for Selection Bias and the Role of Complementary Inputs

We analyze yield effects of tissue culture (TC) banana technology in the Kenyan small farm sector, using recent survey data and an endogenous switching regression approach. TC banana plantlets, which are free from pests and diseases, have been introduced in East Africa since the late-1990s. While field experiments show significant yield advantages over traditional banana suckers, a rigorous assessment of impacts in farmers' fields is still outstanding. A comparison of mean yield levels between TC adopters and non-adopters in our sample shows no significant difference. However, we find a negative selection bias, indicating that farmers with lower than average yields are more likely to adopt TC. Controlling for this bias results in a positive and significant TC net yield gain of 7%. We also find that TC technology is more knowledgeintensive and more responsive to irrigation than traditional bananas. Simulations show that improving access to irrigation could lift TC productivity gains to above 20%. The analytical approach developed and applied here may also be useful for the evaluation of other knowledgeintensive package technologies and innovations in perennial crops. --Biotechnology,adoption,productivity,impact,endogenous switching regression,Kenya

Information Asymmetries and Technology Adoption: The Case of Tissue Culture Bananas in Kenya

Classical innovation adoption models implicitly assume homogenous information flow across farmers, which is often not realistic. As a result, selection bias in adoption parameters may occur. We focus on tissue culture (TC) banana technology that was introduced in Kenya more than 10 years ago. Up till now, adoption rates have remained relatively low. We employ the average treatment effects approach to account for selection bias and extend it by explicitly differentiating between awareness exposure (having heard of a technology) and knowledge exposure (understanding the attributes of a technology). Using a sample of Kenyan banana farmers, we find that estimated adoption parameters differ little when comparing the classical adoption model with one that corrects for heterogeneous awareness exposure. However, parameters differ considerably when accounting for heterogeneous knowledge exposure. This is plausible: while many farmers have heard about TC technology, its successful use requires notable changes in cultivation practices, and proper understanding is not yet very widespread. These results are also important for other technologies that are knowledge-intensive and/or require considerable adjustments in traditional practices

Impact of tissue culture banana technology in Kenya: A difference-in-difference estimation approach

Most micro-level studies on the impact of agricultural technologies build on cross-section data, which can lead to unreliable impact estimates. Here, we use panel data covering two time periods to estimate the impact of tissue culture (TC) banana technology in the Kenyan small farm sector. TC banana is an interesting case, because previous impact studies showed mixed results. We combine propensity score matching with a difference-in-difference estimator to control for selection bias and account for temporal impact variability. TC adoption has positive impacts on banana productivity and profits. The technology increases yields by 40-50% and gross margins by around 100%. These large effects represent the impact of TC technology in combination with improved management practices and higher input use, which is recommended. Looking at the isolated TC effect may underestimate impact because of synergistic relationships. The results suggest that extension efforts to deliver the technological package to smallholder farmers should be scaled up

Impact of Tissue Culture Banana Technology on Farm Household Income and Food Security in Kenya

While tissue culture (TC) technology for vegetative plant propagation is gradually gaining in importance in Africa, rigorous ex post assessments of welfare effects for smallholder farm households is lacking. Using recent survey data and accounting for self-selection in technology adoption, we analyze the impacts of TC banana technology on household income and food security in Kenya. To assess food security outcomes, we employ the Household Food Insecurity Access Scale (HFIAS) a tool that has not been used for impact assessment before. Estimates of treatment-effects models show that TC banana adoption increases farm and household income by 153% and 50%, respectively. The technology also reduces relative food insecurity in a significant way. These results indicate that TC technology can be welfare enhancing for adopting farm households; its use should be further promoted through upscaling appropriate technology delivery systems

Does ownership of improved dairy cow breeds improve child nutrition? A pathway analysis for Uganda

PRIFPRI3; ISI; CRP4; Capacity Strengthening; A Ensuring Sustainable food production; B Promoting healthy food systems; D Transforming Agriculture; G Cross-cutting gender theme; Feed the Future Innovation Laboratory for NutritionDSGD; A4NH17 pagesCGIAR Research Programs on Agriculture for Nutrition and Health (A4NH

Adoption and Impact of Improved Cow Breeds on Household Welfare and Child Nutrition Outcomes: Empirical Evidence from Uganda

There is increasing evidence that improved agricultural technologies benefit smallholder farmers in sub-Saharan Africa. This evidence is however relatively clearer for innovations in smallholder crop production systems as compared to innovations in livestock production systems. Moreover, it is unclear whether the benefits of technology adoption in livestock systems are uniform across small and relatively large farmers. This study uses a national representative sample of 906 households to rigorously assess the impact of adoption of improved dairy cow breeds on enterprise-, household-, and individual child-level nutrition outcomes in Uganda. We find that adopting improved dairy cows significantly increases milk yield, household’s orientation to milk markets, and food expenditure. Consequently, adoption substantially reduces household poverty and stunting for children younger than age five. Considering heterogeneity, we find that adopting households with small farms increase milk yield, food expenditure and reduce poverty substantially while large farms increase not only ownmilk consumption and commercialization but also nutrition outcomes of children younger than age five

Impact of tissue culture banana technology on farm household income and food security in Kenya

PRIFPRI3; ISIDSG

Improved dairy cows in Uganda: Pathways to poverty alleviation and improved child nutrition

The introduction and dissemination of improved dairy cow breeds in Uganda is arguably the most significant step taken to develop a modern and commercial dairy industry in the country over the last two decades. This study uses a nationally representative sample of Ugandan households to rigorously examine the impact of adoption of improved dairy cow breeds on enterprise-, household-, and individual child-level nutrition outcomes. We find that adopting improved dairy cows significantly increases milk productivity, milk commercialization, and food expenditure.Non-PRIFPRI1; Theme 6; Subtheme 6.2; GRP32DSG

The case of tissue culture bananas in Kenya

PRIFPRI3; ISIDSG

Accounting for selection bias and the role of complementary inputs

PRIFPRI3; ISI; CRP2DSGD; PIMCGIAR Research Program on Policies, Institutions, and Markets (PIM