Document Type: Research Paper
Ferdowsi University of Mashhad, Faculty of Agriculture, P.O. Box 91775-1163, Mashhad, Iran.
Department of Agroecology, Environmental Sciences Research Institute, Shahid Beheshti University, G.C., P.O. Box 19835-196, Tehran, Iran.
Yield gap analysis provides an essential framework to prioritize research and
policy efforts to reduce yield constraints. To identify options for increasing
chickpea yield, the SSM-chickpea model was parameterized and evaluated. The
model was applied to analyze seed yield at both potential and water limited
production levels and subsequently to find the yield gap for nine different
locations. Study locations are selected to represent major chickpea-growing areas
of Khorasan Razavi province (located between 37◦ N and 33◦ S latitude and 61◦ E
and 56◦ W longitude). The average simulated potential yield of chickpea across all
study locations was 2251 kg ha-1, while for the water limited yield was 1026
kg ha -1, indicating 54% lower due to adverse soil moisture conditions. Average
irrigated and rainfed actual yields were 64% and 79% less than simulated potential
and water limited yields respectively. Maximum and minimum of simulated
potential yield minus simulated water limited yield (YGMM) and simulated potential
yield minus irrigated actual yield (YGMI) were observed in Torbat-Jam and
Quchan, respectively. Generally, YGMI and YGMM showed an increasing trend from
the north (including Neishabur, Mashhad, Quchan and Daregaz) to the south of the
study province (Torbat-Jam and Gonabad). In comparison to other indices,
simulated water limited yield minus rainfed actual yield (YGMR) was very low
because both simulated water limited and average rainfed actual yields were low in
these locations. Overall, YGMR was almost unaffected by the quantity of rainfall
received at these locations.
Keywords: Actual yield; Benchmarking; Modelling; Potential yield.