Global synthesis of drought effects on cereal, legume, tuber and root crops production: A review

Abstract

As a result of climate change, drought is predicted to pose greater pressure on food production system than in the past. At the same time, crop yield co-varies with both environmental (e.g., water, temperature, aridity) and agronomic variables (i.e., crop species, soil texture, phenological phase).To improve our quantitative understanding on the effect of these co-varying factors on agricultural productivity, we synthesized previous meta-analysis studies summarizing the results of numerous independent field experiments on drought and its effect on the production of cereal, legume, root and/or tuber (root/tuber) crops. We also included new crops species that were not covered in previous meta-analyses and the effects of heat stress. Our results indicated that cereals tended to be more drought resistant than legumes and root/tubers. Most crops were more sensitive to drought during their reproductive (i.e., grains filling, tuber initiation) than during their vegetative phase, except for wheat, which was also sensitive during vegetative phase. Recovery from drought impact at reproductive phase was either: (i) unfeasible for crops experiencing damage to their reproductive organs (e.g., maize, rice) or (ii) limited for root/tuber crops, provided that water was abundant during the subsequent root/tuber bulking period. Across soil texture, the variability of yield reduction for cereals was also lower in comparison to legume or root/tuber crops, probably due to the extensive and deep rooting system of cereal crops. As crop species, plant phenology, and soil texture were important co-varying factors in determining drought-induced crop yield reduction, no single approach would be sufficient to improve crop performance during drought. Consequently, a combination of approaches, particularly site-specific management practices that consider soil conditions (i.e., intercropping, mulching, and crop rotation) and selection of crop varieties adjusted to the local climate should be adopted in order to improve the sustainability of agricultural production in a changing climate.3

Statistical Modeling of Phenotypic Plasticity under Abiotic Stress in Triticum durum L. and Triticum aestivum L. Genotypes

“…Averaged over six years of field experiments [43], and despite its larger yield potential, T. durum produced 25%-30% less grain yield than T. aestivum; whereas, grain yield, in accordance with earlier reports [20], was reduced by 28 and 23%, respectively due to PS II when compared to PS I. Although T. durum has better water and nutrients use efficiencies under high-yielding environments and it tolerates abiotic stress better than T. aestivum, it has lower grain yield than T. aestivum under low-yielding environments [21,40]; however, both wheat genotypes responded similarly to changes in abiotic stresses in this and other studies [20]. It was speculated [72] that the constitutively larger kernel weight in T. durum is associated with its lower fruiting efficiency when compared with T. aestivum; nevertheless, kernels m −2 in both genotypes was the most sensitive yield component to abiotic stress in this and other studies [39,73], presumably due to its larger plasticity and high heritability (Table 2).…”

“…Differences in PPs between the wheat genotypes are likely linked to the level of agronomic and genetic improvement that they underwent [21]. Stress phases caused a shift in frequency distributions of PPs, deviation from normality, and skewness in a few traits, and exposed many differences between the wheat genotypes in their reaction to abiotic stresses during both stress phases (Figure 1).…”

Drought‐induced changes in root biomass largely result from altered root morphological traits: Evidence from a synthesis of global field trials

“…Drought‐induced decrease in RD may be associated with the greater embolism, leading to higher RM (Chapin et al, ; Chaves, ; Roumet et al, ). We also found that the responses of RL and SRL to drought differed significantly among plant functional groups (Figure ), which may be attributed to the difference in strategies of different groups to obtain nutrients and water to support their growth in response to drought stress (Daryanto, Wang, & Jacinthe, ). For example, herbs may have stronger C‐use efficiency than woody plants under low drought intensity because thinner RD of herbs may benefit plants to enhance the ability to leverage photosynthetic C by reducing reliance on mycorrhizae (Ma et al, ).…”

“…Increased R/S is a plant avoidance mechanism in response to drought when drought increases the proportion of RB relative to aboveground biomass (Hermans, Hammond, White, & Verbruggen, 2006;Hodge, 2009;Zhou et al, 2017). Meanwhile, the response of R/S to drought varied among plant functional types ( Figure 6), which might be attributed to the different strategies of plant functional types to obtain water and nutrients and distribution of RB at different soil profile (Daryanto et al, 2017). For example, more C can be easily allocated into roots in response to drought due to thinner RD in herbs than woody plants (Ma et al, 2018).…”

A Probabilistic Risk Assessment of the National Economic Impacts of Regulatory Drought Management on Irrigated Agriculture

“…Many previous studies have evaluated the impacts of drought on crop yields for rainfed (e.g., Popova et al, ; Potopová et al, ) and irrigated (e.g., Daryanto et al, , ; Sweet et al, ; Trnka et al, ) systems. This has also extended into the economic impacts of drought using market prices and production functions at the basin scale (e.g., Kirby et al, ), input‐output analysis (e.g., Pérez y Pérez & Barreiro‐Hurle, ), Ricardian cross‐sectional analysis of net revenues, and computable general equilibrium models to capture economy‐wide and global‐scale changes of climate change (Mendelsohn & Dinar, ).…”