More aboveground biomass, phosphorus accumulation and remobilization contributed to high productivity of intercropping wheat

Document Type: Research Paper

Authors

1 Department of Plant Nutrition and crop Cultivation and Tillage, Sichuan Agricultural University, Chengdu, China.

2 Department of Plant Nutrition, China Agricultural University, Beijing, China

Abstract

Intercropping often results in increasing production than sole per unit land area, but the
underlying mechanisms are poorly understood. Plants showed different physiological
characteristics in intercropping and sole. However, less information was shown the relationships
between plant aboveground biomass (AB), phosphorus accumulation (PB) and remobilization
and the yield advantage. Here, field experiments were designed as split plot and carried out in
2012 and 2013 with three P levels (0, 40 and 80 kg P ha
-1) in wheat (Triticum aestivum L.)/
maize (
Zea mays L.) relay intercropping and sole. The study measured grain yield, AB and P
accumulation and remobilization of wheat. Averaged grain yield of intercropping wheat
increased 3.9 Mg ha
-1 in 2012 and 2.7 Mg ha-1 in 2013 compared with that of the corresponding
sole and the grain yield of intercropping wheat changed with the border row (BR) > the inner
row (IR) > the sole wheat (SR), the grain yield in BR was contributed by 58.2% to intercropping
wheat. The PA was consistent with AB accumulation, which in intercropping was higher than
that in sole over the entire growing season. Close correlations between yield and AB
remobilization and P remobilization were observed. The yield of BR was higher from 39.3% to
88.0% than that of SR wheat, as mainly attributed to more AB and P accumulation across the
whole growing season and more remobilization from pre-anthesis to grain filling stage. More
than 40 kg P ha
-1 did not result in any further increasing in yield and did not enhanced the
physiological processes associated with AB and P remobilization, indicating that P fertilizer and
agronomic management should be intensified synchronously in field to achieve high yield and
sustainability.

Keywords