Application of K and Zn Influences the Mineral Accumulation More in Hybrid Than Inbred Maize Cultivars

Maize (Zea mays L.) is an important crop used for feeding humans and cattle globally. Deficiency of potassium (K) and zinc (Zn) adversely impacts the maize crop productivity and quality. However, the application of these nutrients shows variant responses in different maize cultivars. To understand this perspective, the current study aimed at investigating K and Zn's optimal concentration in different hybrid and inbred maize cultivars. The treatments were based on three zinc levels (0, 6, and 12 mg Zn kg(-1)) and K levels (0, 30, and 60 mg kg(-1)), and their respective combinations. The experiment results showed that combined fertilization approaches of Zn and K (Zn12K60) improved the plant biometric, and physiological attributes of maize crop. The results revealed a significant increase in plant height (45%), fresh weight (70%), and dry weight (45%). Similarly, physiological attributes significantly improved the relative water content (76.4%), membrane stability index (77.9%), chlorophyll contents (170%), and photosynthetic rate (130%) in both inbred and hybrid genotypes. Furthermore, Zn and K (Zn12K60) increased transpiration rate (E), stomatal conductance (Ci), and internal CO2. In conclusion, maize hybrids (Neelam and DK-6142) were observed best compared with inbred (Afghoi and P-1543) cultivars with the combined application of Zn and K (Zn12K60). Thus, these inbred varieties should be preferred for fodder requirement with optimum fertilizer (Zn12K60) application in Zn deficient soils.

Automated summary

This study investigated the optimal concentrations of potassium (K) and zinc (Zn) in different hybrid and inbred maize cultivars and found that combined fertilization approach (Zn12K60) significantly improved the plant biometric and physiological attributes of maize crops. Maize hybrids showed better performance compared to inbred cultivars under the combined application of Zn and K (Zn12K60), indicating their suitability for fodder production in Zn deficient soils.