Pre- and post-anthesis dry matter and nutrient accumulation, partitioning, remobilization and crop productivity of maize under the long-term integrated crop management practices

Abstract

Integrated crop management (ICM) practices play a critical role in enhancing the maize’s physiological growth, optimizing the dry matter and nutrients’ acquisition coupled with increased productivity. The effect of these comprehensive long-term ICM practices was investigated on the growth and physiological characteristics, dry matter and nutrient accumulation, partitioning and remobilization, productivity, and sustainability of the maize under the field conditions in semi-arid regions of sub-tropical India. Eight ICM practices were evaluated over nine consecutive years (2014–2023), which included ICM_1–4: conventional (CT); ICM_5–6: double zero-tilled and ICM_7–8: triple zero-tilled ICM practices. ICM_5–8 practices improved maize growth attributes over the conventional ICM practices, wherein the increment in the relative growth and the net assimilation rates were 7.9–8.2 %, and 14.1–15.5 %, respectively. Further, these practices improved the photosynthesis rates (9.7–20.5 %), stomatal conductance (11.5–19.1 %), and transpiration efficiency (5.4–14.2 %). In addition, the residue-retained practices showed a greater reduction in canopy temperature (-3.2 to −4˚C) over the CT (-1.6 to −2.7˚C), along with the enhancements in total chlorophyll (31.1–49.7 %), and carotenoids (26.9–50.3 %) at anthesis stage. Additionally, the ICM_5–8 demonstrated the increases of 38.8–60.1 %, 168–219 %, and 45.9–81.3 % in pre-anthesis translocation of nitrogen (N), phosphorus (P), and potassium (K), respectively over the conventional ICM practices. Likewise, the post-anthesis N, P, and K translocation increased by 20.3–29.4 %, 34.7–71.5 %, and 37.9–40.1 %, respectively under the residue-retained double and triple-ZT ICM_5–8 practices. On average, the residue-retained ICM_7–8 practices led to a ∼19 % and ∼12 % increase in the grain and stover yields, respectively over the ICM_1–4 practices. In maize, the highest sustainable yield index too was recorded under the ICM_5–8 practices, which was ∼19 % higher than the ICM_1–4. The study underscores the potential of adopting residue-retained zero-tilled ICM practices to enhance the maize yields and continuance of sustainability in the long-run.