Looks matter? Field performance and farmers' preferences for drought-tolerant maize in Kenya

Abstract

Context

To help farmers adapt to climate change, breeding programs have developed drought-tolerant (DT) maize varieties, but varietal turnover among smallholder farmers is slow. One possible reason for low adoption is that DT varieties produce higher yields than older hybrid maize varieties but are not visibly more drought tolerant, especially if morphology is a factor in farmers' varietal choice.

Objectives

Motivated by this conjecture, our first objective is to compare the drought tolerance of a new hybrid DT maize variety and older varieties under farmer-managed conditions in terms of both morphology and yields. Our second objective is to analyze whether increasing farmers' exposure to this variety increases their awareness of its DT traits and subsequent adoption.

Methods

We leverage a project that provided seed trial packs of a new DT maize variety to randomly selected farmers in seven counties in Kenya with varying rainfall conditions. Picture-based crop monitoring across two seasons yielded a novel panel dataset of 18,225 smartphone images labeled for drought damage, and, for a subsample of fields, yields. We use this dataset to compare the performance of promoted and commonly grown varieties. We then use exogenous variation in receiving trial packs to analyze how providing trial packs affects varietal preferences and adoption.

Results and conclusion

The promoted variety produces higher yields than other varieties. Under good conditions, it also appears visibly less damaged during the flowering stage, but morphological differences disappear under more severe moisture stress, and once the crop reaches maturity. Consistent with these observations, treatment farmers do not perceive this variety to be more drought tolerant than other varieties and are more likely to plant the promoted variety only when receiving a free trial pack.

Significance

It could be that limited visibility of DT traits hinders sustained adoption. Increasing adoption of DT varieties to enhance climate change adaptation in drought-prone regions may require facilitating prolonged learning and experimentation opportunities, increasing awareness of how DT traits manifest themselves in terms of yields and morphology under varying rainfall conditions, and, costs permitting, selecting for visible DT traits in plant breeding.