.
The global burden of pathogens and pests on  major food crops 
Serge Savary, Laetitia Willocquet, Sarah Jane Pethybridge, Paul Esker, Neil McRoberts  and  Andy Nelson

Crop pathogens and pests reduce the yield and quality of agricultural production. They cause substantial economic losses and  reduce food security at household, national and global levels. Quantitative, standardized information on crop losses is difficult  to compile and compare across crops, agroecosystems and regions. Here, we report on an expert-based assessment of crop  health, and provide numerical estimates of yield losses on an individual pathogen and pest basis for five major crops globally  and in food security hotspots. Our results document losses associated with 137 pathogens and pests associated with wheat,  rice, maize, potato and soybean worldwide. Our yield loss (range) estimates at a global level and per hotspot for wheat (21.5%  (10.1–28.1%)), rice (30.0% (24.6–40.9%)), maize (22.5% (19.5–41.1%)), potato (17.2% (8.1–21.0%)) and soybean (21.4%  (11.0–32.4%)) suggest that the highest losses are associated with food-deficit regions with fast-growing populations, and  frequently with emerging or re-emerging pests and diseases. Our assessment highlights differences in impacts among crop  pathogens and pests and among food security hotspots. This analysis contributes critical information to prioritize crop health  management to improve the sustainability of agroecosystems in delivering services to societies.

The top left chart shows global losses and production for wheat, rice, maize, potato and soybean.  The other charts are specific to each food security hotspot. The upper portion of each chart shows the kilograms of crop production per person   (2010–2014 averages) on a log 10  scale. The lower portion shows the percentage yield losses across all reported P&Ps. Food security hotspot charts only  show losses where there were sufficient survey responses to estimate the loss. The grey dots represent the world averages per crop. The global map shows  the location of the eight food security hotspots. Above-average crop losses were found for: wheat (25.7%), rice (31.3%) and (maize  30.1%) in SSA; rice (40.9%), maize (41.1%) and potato (21.0%) in the IGP; wheat (28.1%) and rice (32.2%) in China; soybean (32.4%) in SB&A; and  wheat (24.9%) in NWE. However, lower than average crop losses were recorded for: wheat (17.9%), maize (21.3%) and potato (8.1%) in USM&C; wheat  (10.1%) and potato (12.6%) in WANA; and wheat (16.6%) in the IGP.

https://go.nature.com/2UIeW6A

..