The present research was carried out to study effects of animal manure and superabsorbent polymer on leaf relative water content, cell membrane stability and leaf chlorophyll content (SPAD) of corn under drought stress in Fars Agricultural Research Station (Iran). The experimental design was split plot based on randomized complete blocks (RCBD) with three replicates. Water stress was applied by three different irrigation intervals (irrigation after 70, 105 and 140 mm evaporation of basin class A) which were allocated to main plots. A combination of six levels of animal manure and superabsorbent polymer (types: superab A200) allocated to subplots as follows: S1: control, S2: 100% animal manure (40 t/ha), S3: 100% super absorbent polymer (200 kg/ha), S4: 50% animal manure+50% superabsorbent polymer, S5: 35% animal manure+65% superabsorbent polymer, S6: 65% animal manure+35% superabsorbent polymer. Results showed that the highest leaf relative water content (RWC) was obtained with 100% superabsorbent polymer (200 kg/ha), and it reduced by increasing drought stress. Cell membrane stability (CMS) increased with increasing drought stress and decreased by using animal manure and superabsorbent polymer. Leaf chlorophyll index (SPAD values) increased in response to drought stress and by using different combinations of animal manure and superabsorbent polymer. 1000-seed weight and grain yield was decreased by drought stress. Grain yield decreased by yield components reduction, especially 1000-seed weight due to drought stress. 1000-seed weight and grain and biological yield increased by using animal manure and superabsorbent polymer together as maximum yield grain was obtained by using 65% animal manure and 35% superabsorbent polymer.

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