Suitability and benefits from intercropped sorghum–amaranth under partial root‐zone irrigation
Amirsaleh Baghdadi, Farzad Paknejad, Farid Golzardi, Masoud Hashemi, Mohammad Nabi Ilkaee
Abstract
Abstract BACKGROUND The production of sufficient animal feed in arid and semi‐arid regions plays a significant role in food security in these areas. The present study was conducted based on the hypothesis that intercropping of sorghum and amaranth, comprising relatively drought tolerant forages, will enhance the yield and quality of the feed under limited irrigation water availability. RESULTS Implementation of fixed alternate furrow irrigation (FFI) and alternate furrow irrigation (AFI) resulted in a saving of 22.5% and 19.7% of irrigation water, respectively. However, the water saving declined both yield and quality of forage. In conventional furrow irrigation (CFI), the highest dry matter (DM) yield was 15.5 Mg ha −1 , obtained from S 50 –A 50 treatment. In FFI and AFI, sole sorghum produced the highest DM. However, their maximum yields (11.2 and 12.6 Mg ha ‐1 , respectively) were not significantly different from yields in S 75 –A 25 intercropping ratios. Irrigation water use efficiency (IWUE) was similar in CFI and AFI and considerably higher than FFI. Sorghum monoculture and the S 75 –A 25 intercropping had the highest IWUE (3.4 and 3.3 kg m −3 ), whereas IWUE of the sole amaranth was 1.7 kg m −3 . The partial land equivalent ratio and monetary advantage index of amaranth and sorghum indicated that sorghum would benefit from intercropping as long as its ratio in the intercropping is more than 25%. CONCLUSION When sufficient irrigation is available, intercropping of sorghum and amaranth can considerably improve yield and quality of emergency feed. However, the benefits from intercropping faded under the two partial root‐zone irrigation methods used in the present study. © 2021 Society of Chemical Industry.