Beneficial effects of antitranspirants on water stress tolerance in maize under different plant densities in newly reclaimed land

Background The global freshwater shortage is an important issue threatening the sustainable development of agriculture and food security. A field study was conducted in two seasons, i.e., 2019 and 2020, in the newly reclaimed land at Village 8, El-Minia Governorate, Egypt, to evaluate maize crop response to three irrigation levels (IL 1 = 80, IL 2 = 70, and IL 3 = 60% of the crop evapotranspiration “ETc”), three plant densities (PD 1 = 17.500, PD 2 = 23.333, and PD 3 = 35.000 plants fed −1 ), and three antitranspirants treatments (An 1 = control, An 2 = kaolin at 6%, and An 3 = chitosan at 150 L fed −1 ). The experiment was designed as a randomized complete block design (RCBD) using a split plot in strips. Results Results revealed that the irrigated maize plants with IL 1 (80% of ETc) recorded the maximum values for all traits such as vegetative growth, phenology, and yield and its attributes in both seasons. The heaviest value of grain yield (3.15 and 3.10 tonnes fed −1 , where 1 feddan = 0.42 hectare) was realized from IL 1 treatment in the 1st and 2nd seasons, respectively. Plant density of 35.000 plants fed −1 (PD 3 ) produced the greatest values of leaf area index (6.70 and 6.85), more days to 50% for each of tasseling (62.16 and 61.99 days), and silking (63.63 and 63.73 days), heaviest grain yield (3.11 and 3.16 ton fed −1 ) and greater water use efficiency WUE (1.46 and 1.48 kg m −3 ) in both seasons, respectively. Conclusions Foliar spraying with antitranspirants, i.e., kaolin at 6%, led to a tremendous impact on all studied traits by alleviating the water stress and reducing the rate of transpiration. The effect of second-order interaction among IL 1 × PD 3 × An 3 indicated a significant increase in grain yield by 69.91% as compared with the interaction of IL 3 × PD 1 × An 1 in the 2020 season only. CS 10 single-cross maize realized the highest productivity and most efficient use of available resources via using a sowing density of 35.000 plant fed −1 , foliar spraying with kaolin at 6%, and irrigation level (80% of ETc) under El-Minia conditions.