Potential of Integrating Biochar and Deficit Irrigation Strategies for Sustaining Vegetable Production in Water-limited Regions: A Review

Abstract

<jats:p>Water shortage is one of the major challenges faced by the current agricultural systems worldwide, especially in arid and semi-arid regions. Deficit irrigation (DI), a water-saving strategy of applying less water than crop evapotranspiration (ET<jats:sub>c</jats:sub>) demands, has been extensively investigated in different crops, including water-intensive vegetables. The DI strategies such as regulated deficit irrigation (RDI) and partial root zone drying (PRD) generally increase water use efficiency (WUE) and have emerged as potential practices to save water for agricultural sustainability. However, in view of the sensitivity of shallow-rooted vegetable crops to water stress, DI is often associated with yield losses. A review of 134 DI reports of vegetable crops revealed significant reductions in yield under all DI levels in 52% of cases and yields statistically similar to those of full irrigation (100% ET<jats:sub>c</jats:sub> in most cases) under small water deficits in 44% of cases, thereby raising concerns about the sustainability of vegetable production under DI. Biochar, a carbon-rich co-product of pyrolysis of organic matter, is increasingly undergoing study as a soil amendment to mitigate drought stress and is being explored as an additional practice with DI to minimize the yield losses due to water deficits. This work reviews the effects of biochar application on growth, yield, physiology, and WUE of different vegetable crops under DI regimes to determine the potential of biochar and DI used in combination to sustain vegetable productivity in water-limited areas. Overall, the addition of biochar under DI has helped to compensate for yield losses of vegetables and further enhanced WUE. However, field studies investigating long-term soil–biochar interactions that strongly conclude the impact of biochar under moisture stress conditions are lacking.</jats:p>

Response of Potato (Solanum Tuberosum L.) to the Application Rates of Biochar and Number of Irrigations

“…In another study, conventional furrow irrigation was effective for growth and yield parameters of potato; indicating differences between irrigation methods (Verma et al, 2017). The addition of biochar under deficit irrigation helped to compensate for yield losses of vegetables and further enhanced water use efficiency (Singh et al, 2019). We also found that at least one irrigation could be cut off with the application of biochar.…”

Evaluating the Effects of Biochar with Farmyard Manure under Optimal Mineral Fertilizing on Tomato Growth, Soil Organic C and Biochemical Quality in a Low Fertility Soil

“…However, the majority of these studies investigated cereals crops and effects of biochar on vegetable crops are less reported, e.g., [38,39]. A review by Singh et al [40] reported 10 studies on the effects of biochar on vegetables and found that nine of these studies showed that biochar enhanced vegetable growth, yield and water use efferences. Biochar enhanced tomato growth and soil fertility but did not affect the quality and yield [41].…”

Study on the Suitable Irrigation Amount of Microporous Membrane Water-Fertilizer Integration of Tomato in Spring in Plastic Greenhouse

“…The results showed that drip irrigation and infiltration irrigation could save more than 50% water, yield improvement and increase water use efficiency by 2-5 times (Hanson and May, 2006;Karlberg and Vries, 2004;Song et al, 2009). New water-saving irrigation technologies, such as drip irrigation and infiltration irrigation, have good water-saving and production increasing effects, but they need to install supporting pressure equipment, water pipeline and emitter, which increased the cost and need high water quality requirements (Li et al, 2019;Mostafa et al, 2018;Singh et al, 2019) and ultimately limit the application of water-saving irrigation technology in agricultural production. The perforated membrane is used to replace the pipes, such as drip irrigation belt and drip irrigation pipe and the perforated membrane is laid in the ridged ditch and then a layer of plastic film is covered on it (Wang et al, 2020b).…”