Effect of irrigation regimes and application of barley residue, zeolite and superabsorbent polymer on forage yield, cadmium, nitrogen and some physiological traits of corn and sorghum

摘要

In water deficit conditions, planting the proper crop, utilizing efficient cropping methods and using soil amendments can reduce the harmful effects of drought stress. Therefore to investigate some agronomic and physiological characteristics of corn and sorghum under various irrigation regimes and combination treatments of barley residue, zeolite, and superabsorbent polymer (RZS), two separate experiments (each plant, one experiment) were conducted o ver two years in Iran. A randomized complete block design arranged in a split plot was used with three replications. Two irrigation regimes of normal irrigation and water deficit stress based on 70 mm and 140 mm cumulative pan evaporation, respectively, we re compared in main plots. Five RZS treatments, ( I ) - 10 t ha - 1 zeolite + 4.5 t ha - 1 residue (ZR), ( II ) - 60 kg ha - 1 superabsorbent + 4.5 t ha - 1 residue (SR), ( III ) - 5 t ha - 1 zeolite + 30 kg ha - 1 superabsorbent +4.5 t ha - 1 residue (ZSR), ( IV ) - 4.5 t ha - 1 residue (R), and ( V ) – control (C), were compared in subplots. Under water deficit stress, Malondialdehyde and proline content in leaf increased, but the forage yield decreased significantly. In both plants, zeolite application (ZR and ZSR treatments) had the highest forage yields and the lowest cadmium concentrations for forage. Using 4.5 t ha - 1 residues (R), significantly affected increasing RWC and decreasing leaf Malondialdehyde and proline. The forage fresh yield of corn and sorghum (first cutting) wer e 62.6 and 48.5 t ha - 1 , respectively. We recommend planting corn using 5 t ha - 1 zeolite and 4.5 t ha - 1 residues in a double - cropping system.