Suitability and benefits from intercropped sorghum–amaranth under partial root‐zone irrigation

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.

The use of alternative irrigation and cropping systems in forage production may alleviate the water scarcity in semi‐arid regions

“…In the current study, intercropped forage sorghum and amaranth improved dry matter yield and the quality of the forage mix, as long as sorghum constituted 50% of the intercropped system. The results are in agreement with the earlier report indicated that 50:50 intercropping ratio of sorghum and amaranth performed best compared with other ratios 9 . The 50:50 ratio of sorghum and amaranth boosted the forage yield by over 25% compared with high‐yielding monoculture forage sorghum.…”

“…33,5 This inefficient irrigation method is well-known for having the lowest application efficiency due to its deep percolation from irrigated fields. 9 Seeking alternative irrigation strategies, identifying lower water demand crops, and adopting more sustainable cropping systems are among the strategies to enhance IWUE. In the case of forage crops, in addition to total biomass yield, the quality of forage which is commonly expressed as energy content or milk value seems more appropriate than just dry matter yield.…”

“…Amaranth is demonstrated to be considered an acceptable drought tolerance forage, due to its deep tap root, and also a crop that can thrive in marginal and low-fertility soils. 15,9 The overall low water requirement of amaranth to produce dry matter and its high forage quality are among features to candidate this crop to be used as an alternative or a new forage crop in semi-arid regions. 16 The benefits of intercropping in improving water-use efficiency have been reported.…”

Effect of water stress on yield stability, water productivity, and canopy temperature of rice genotypes

“…Due to climate change in recent years and the significant yield reduction due to drought stress, it is necessary to identify drought-resistant genotypes (Baghdadi et al, 2021). A comparison between drought tolerance indices and physiological characteristics showed that genotype G8 had the highest Ys, WP, MP, GMP, HM, STI, and YI, and low CT, so it was identified as the most drought-tolerant genotype (Table 6).…”

“…In recent years, climate change and the subsequent increase in the incidents and duration of drought have threatened crop production and food security (Balazadeh et al, 2021;Farhadi et al, 2022). Drought stress is one of the most significant factors limiting crop yield, it has different effects at different stages of plant development and profoundly affects agricultural systems and food production (Golzardi et al, 2017;Ashoori et al, 2021;Baghdadi et al, 2021). However, rice requires a large amount of water for its growth and development (Sabouri et al, 2022), and drought is the most critical limiting factor for rice growth and production (Pandey and Shukla, 2015).…”