Optimum Zinc Fertilization and Sowing Date Improved Growth, Yield Components, and Grain Zn Contents of Bread Wheat Under Different Tillage Systems

Bread wheat (Triticum aestivum L.) is a staple food of millions across the globe. However, wheat productivity is very low due to inappropriate sowing time, conventional tillage system, and imbalanced fertilization in semiarid regions. Thus, the objective of the study was to assess the impact of different zinc (Zn) application rates on yield and Zn contents of wheat grown under two tillage systems at three sowing times in the semiarid region. The current field experiment consisted of four (04) zinc (Zn) application rates (control 0 kg ha−1 (Zn1), 5 kg ha−1 (Zn2), 10 kg ha−1 (Zn3), and 15 kg ha−1 (Zn4)); factorially combined with two tillage systems (zero tillage (ZT), conventional tillage (CT)) and three sowing dates (SD1= 15th November (optimal), SD2= 05th December (late), SD3= 25th December (very late)). The study was conducted during the crop season of 2019–2020 and 2020–2021. The experimental results clearly demonstrated that Zn fertilization and sowing dates significantly affected the growth, yield and grain Zn content of wheat. However, different tillage systems did not significantly affect any parameter during both years of field trial. Among sowing dates, wheat crop sown on 15th November produced highest biological yield (6378 to 6676 kg ha−1) and grain yield (4663 to 4854 kg ha−1) and zinc grain content (30.8 to 32.3 mg kg−1) in comparison to wheat crop sown on 5th December, and 25th December during both years, respectively. Furthermore, zinc application at 10 kg ha−1 produced higher biological yield (6771 to 7088 kg ha−1), grain yield (4951 to 5153 kg ha−1), and zinc grain content (34.2 to 35.7 mg kg−1) during both the years, respectively. Zinc application at 10 kg ha−1 in wheat crop sown on 15th November seems to be a viable option to achieve higher grain yield with high grain Zn contents under semi-arid region.