Early plant height: A defining factor for yields of silage maize with contrasting phosphorus supply. (24th January 2021)

• Record Type: Journal Article
• Authors: Pedersen, Ingeborg Frøsig; Christensen, Julie Therese; Sørensen, Peter; Christensen, Bent T.; Holton Rubæk, Gitte
• Is Part Of: Soil use and management. Volume 38:Number 1(2022)
• Page Start: 537
• Page End: 548
• Publication Date: 2021-01-24
• Subjects: growth models -- height development -- long‐term experiment -- soil fertility -- water‐extractable phosphorus; Soil management -- Periodicals; 631.4
• DOI: 10.1111/sum.12697
• Languages: English
• ISSNs: 0266-0032

Abstract

Abstract: Silage maize ( Zea mays L.) is an important crop for forage on Northwestern European dairy cattle farms. We examined the effect of readily available soil phosphorus (P) on early maize growth and linked in‐season height growth to final harvest yield using field plots with contrasting P supply in a one‐year study embedded in a long‐term experiment. Water‐extractable P (Pw) was used as a proxy for readily available P in soil. Plant height, dry matter (DM) accumulation, P and nitrogen (N) uptakes were determined eight times from the two‐leaf stage until final whole‐crop harvest and fitted to logistic growth models. The models revealed that the final yield was significantly related to the time required to reach the maximum rate of height growth (occurring from 330 to 485 accumulated growing degree units, GDU), but not the time required to reach the maximum rate of DM accumulation (occurring from 561 to 649 GDU). Furthermore, plant height at the four‐leaf stage and onwards was significantly related to the final harvest yield. Soil Pw linked closely to height growth parameters; higher levels of Pw gave earlier peaks in height growth. For this light sandy loam with a wide gradient in P content, we conclude that suboptimal P supply postpones height growth and reduces final yields. A sufficient P supply links to an early rapid increase in plant height and forms the potential for optimum nutrient uptake and high forage yields. Thus, early‐season plant height may serve as a simple morphometric indicator for final yields.