A study was conducted to evaluate four common coffee (Coffea arabica) varieties in Zimbabwe for drought tolerance and ability to recover. The plants were subjected to drought stress for 21 and 28 days with evaluation of recovery done 14 days after interruptive irrigation. Coffee varieties were not significantly different in initial fresh and dry biomass before stressing ( ). CR95 had significantly accumulated more ( )dry root mass (0.8？g) than the rest of the varieties after 21 days of drought stress. SL28 and CR95 had an 8.3% increase in dry biomass while Cat128 did not gain any dry biomass after 21 days of drought stress. CR95 had significantly more ( ) total dry biomass after 21 days and 28 days of drought stress while SL28 was consistently the least in both periods. Cat129 had the highest recovery gains in dry root, dry shoot, and total dry biomass after 21 days and 28 days of drought stress. Initial root biomass was negatively correlated with changes in total fresh and dry biomass of young coffee ( ) after both 21 and 28 days of drought stress, indicating that root biomass may be the most important factor determining drought tolerance in coffee varieties. 1. Introduction Coffee (Coffea arabica) is produced in many developing countries contributing significantly to poverty alleviation and national economic development. In addition to the importance of coffee in many African national economies in terms of GDP and export earnings, it is directly linked to poverty alleviation as the majority of producers are smallholder farmers, and many rely only on coffee for socioeconomic development [1, 2]. The majority of the coffee produced in Southern Africa is Arabica coffee (Coffea arabica L.) which requires well-distributed rainfalls totaling over 1000？mm per year and temperatures between 24 and 26°C [3–5]. In Zimbabwe, coffee is produced in the eastern highlands districts of Chipinge, Chimanimani, Mutare, and Mutasa where natural climatic conditions approximate requirements and in the northern parts of the country in Guruve, Harare, and Mhangura districts under managed conditions [6, 7]. Coffee is a unique and legal source of income for many smallholder farmers and, as such, production has expanded from traditional areas to marginal areas where meeting crop water requirement is a serious challenge. In addition, in traditional production areas rainfall patterns have become unpredictable and unreliable exposing the coffee plants to frequent and often severe droughts [8, 9]. Changing weather patterns due to climate change and variability are projected to reduce
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