Yield and evapotranspiration characteristics of potato-legume intercropping simulated using a dual coefficient approach in a tropical highland

• DOI: 10.1016/j.fcr.2021.108327
• Publication Date: 2021-10-25T15:30:52Z
• Authors: Shadrack O. Nyawade; Harun I. Gitari; Nancy N. Karanja; Charles K.K. Gachene; Elmar Schulte-Gel...; Monica L. Parker
• Keywords: Crop coefficient; Intercropping; Water balance; Dolichos

An accurate estimation of crop evapotranspiration and soil water balance under potato-legume intercropping is important for improving the productivity rainfed potato. This study quantified evapotranspiration, yield, potato (Solanum tuberosum L.) intercropped with lima bean (Phaseolus lunatus or dolichos (Lablab purpureus in comparison to same crops monocropping. The experiment was set up three agroecological zones Kenya: upper midland (with an altitude range 1500–1653 m above sea level (masl)), lower highland (1892–1923 masl) (2502–2594 masl). dual coefficient approach adopted SIMDualKc model estimate compute balance. partitions into transpiration evaporation by applying both basal coefficient. calibrated validated using field data observed along four growth seasons. coefficients, ratios that were determined. yields different intercrops converted equivalent yield based on price produce. Good agreement between simulated available found modeling efficiency > 0.8. residual mean square error low ranged from 0.01−0.08 m3 m-3 0.03−0.09 mm d-1 evapotranspiration. actual ratio 6−28% greater than sole because legume fully covered ground mid-season, thus limiting energy evaporation. Crop significantly as occurred near its potential rate, not yields. These results support method appropriate tool accurately partition intercropping.