Responses of Soybean Dry Matter Production, Phosphorus Accumulation, and Seed Yield to Sowing Time under Relay Intercropping with Maize

• Main Authors: Shoaib Ahmed, Muhammad Ali Raza, Tao Zhou, Sajad Hussain, Muhammad Hayder Bin Khalid, Lingyang Feng, Allah Wasaya, Nasir Iqbal, Aftab Ahmed, Weigou Liu, Wenyu Yang
• Format: Article
• Language: English
• Published: MDPI AG 2018-11-01
• Series: Agronomy
• Subjects: sowing time; co-growth period; relay intercropping; phosphorus uptake; dry matter
• Online Access: https://www.mdpi.com/2073-4395/8/12/282

Soybean production under maize⁻soybean relay-intercropping system (MSICS) is vulnerable to shading. A study was initiated to investigate the effects of three sowing-times: ST₁, 90; ST₂, 70; and ST₃, 50 days of co-growth period and two phosphorus-rates: P₀, 0; and P₆₀, 60 kg P ha^−1 on soybean under MSICS. Results revealed that ST₃ significantly increased the photosynthetically active radiations, leaf area index, and photosynthetic rate by 72% and 58%, and 61% and 38%, and 6% and 8%, respectively, at full-flowering and full-pod stage of soybean than ST₁. Treatment ST₃, increased the total dry-matter (TDM) and the highest TDM was reached at full-seed (R₆) stage. Similarly, ST₃ considerably increased the dry-matter partitioning to pods and seeds, relative to ST₁, soybean under ST₃ at R₆ had 35% and 30% higher pod and seed dry-matter, respectively. Moreover, ST₃ exhibited the maximum seed-yield (mean 1829.5 kg ha^−1) for both years of this study. Soybean under ST₃ with P₆₀ accumulated 38% higher P, and increased the P content in pods and seeds by 36% and 33%, respectively at R₆ than ST₁. These results imply that by selecting the appropriate sowing-time and phosphorus-rate for soybean, we can increase the TDM and seed-yield of soybean under MSICS.