Climate effects on Barley yield in Mongolia

Abstract

This study examined the influence of climatic factors — principally seasonal precipitation and temperature sums — on summer barley (Hordeum vulgare L.) yield formation at the Plant Science Agricultural Research Institute, Darkhan-Uul Province, Mongolia, over the period 2003–2015. A total of 145 varieties and breeding lines were evaluated under rainfed conditions. Study years were classified by the Hydrothermal Coefficient (HTC) of Selyaninov into humid, normal, dry, and drought categories. Yield ranged from 1.1 to 41.4 t/ha with an overall mean of 19.2 t/ha. The correlation between growing-season precipitation and yield was r = 0.68 across all years, rising to r = 0.91** in drought years. Compared with normal years, yields were 7.4% higher in humid years but declined 43.6% in dry years and 82.2% in drought years. Key yield-structure components — productive stem count (r = 0.82), plant height (r = 0.82), and total stem number (r = 0.75) — showed the strongest correlations with yield at the 99% confidence level. Grain protein content was positively correlated with June–August temperature sums (r = 0.57–0.62*), while grain starch showed an inverse relationship with late-season temperature. These findings highlight the overriding role of water availability on barley productivity in Mongolia's continental climate and underscore the need for drought-tolerant varieties in national breeding programs.