Diethyl Aminoethyl Hexanoate Increase Relay Strip Intercropping Soybean Grain by Optimizing Photosynthesis Aera and Delaying Leaf Senescence

Abstract

Insufficient and unbalanced biomass supply inhibited soybean [Glycine max (L.) Merr.] yield formation in the maize-soybean relay strip intercropping (IS) and monoculture soybean (SS). A field experiment was conducted to explore the soybean yield increase mechanism of DA-6 in IS and SS treatments. In this 2-year experiment, compact maize “Denghai 605” and shade-tolerant soybean “Nandou 25” were selected as cultivated materials. DA-6 with four concentrations, i.e., 0 mg/L (CK), 40 mg/L (D40), 60 mg/L (D60), and 80 mg/L (D80), were sprayed on soybean leaves at the beginning of flowering stage of soybean. Results showed that DA-6 treatments significantly (p < 0.05) increased soybean grain yield, and the yield increase ratio was higher in IS than SS. The leaf area index values and net photosynthesis rate of IS peaked at D60 and were increased by 32.2–49.3% and 24.1–27.2% compared with the corresponding CK. Similarly, DA-6 treatments increased the aboveground dry matter and the amount of soybean dry matter accumulation from the R1 stage to the R8 stage (VDMT) and highest at D60 both in IS and SS. D60 increased the VDMT by 29.0–47.1% in IS and 20.7–29.2% in SS. The TRG at D60 ranged 72.4–77.6% in IS and 61.4–62.5% in SS. The MDA content at D60 treatment was decreased by 38.3% in IS and 25.8% in SS. The active grain-filling day in IS was about 7 days longer than in SS. In D60 treatment, the Vmean and Vmax increased by 6.5% and 6.5% in IS and 5.7% and 4.3% in SS compared with the corresponding CK. Although the pod number and hundred-grain weight were significantly (p < 0.05) increased by DA-6 treatments, the grains per pod were maintained stable. The pod number and hundred-grain weight were increased by 30.1–36.8% and 4.5–6.7% in IS and 6.3–13% and 3.6–5.6% in SS. Thus, the grain yield at D60 was increased by 36.7–38.4% in IS and 21.7–26.6% in SS. DA-6 treatments significantly (p < 0.05) increased soybean grain yield and peaked D60 treatments both in IS and SS.

Compensatory Growth of Soybean after Shade during Vegetative Promotes Root Nodule Recovery

“…At 65, 79, 93 and 121 DAS, three soybean plants in each plot were sampled and cut at ground level. The soybean leaf area was measured as the scan method described by Luo et al (2022). The aboveground parts of the soybean were oven-baked for drying at a constant temperature of 80C for at least three days until a stable weight was reached and the biomass was weighed on an electronic balance.…”

Foliar application of diethyl aminoethyl hexanoate (DA‐6) alleviated summer bentgrass decline and heat damage to creeping bentgrass

“…Foliar application of DA‐6 promoted corn ( Zea mays ) and soybean ( Glycine max ) seedlings growth by improving net photosynthetic rate (Pn), photochemical efficiency (Fv/Fm), and Chl content under optimal conditions (Qi et al., 2013). Soybean leaf senescence was delayed by the DA‐6 in favor of accumulation of aboveground dry matter (Luo et al., 2022). Foliar spraying with DA‐6 not only improved osmotic balance, photosynthesis, and water‐use efficiency (WUE), but also reduced oxidative damage to lipids in white clover ( Trifolium repens ) plants under drought stress (Hassan et al., 2022).…”

Assessing the impact of biochar and nitrogen application on yield, water-nitrogen use efficiency and quality of intercropped maize and soybean

“…This practice promotes farm biodiversity and resource efficiency, including land, nutrients, light and water ( Ahmed et al., 2018 ; Feng et al., 2019 ; Iqbal et al., 2019 ; Raza et al., 2019a ; Raza et al., 2019b ). However, the spatial distributions of soil water and fertilizer vary greatly because of maize-soybean intercropping ( Luan et al., 2021 ; Luo et al., 2022 ). Moreover, the nutrient supply of the system falls short of demand owing to such factors as interspecific competition in the middle and late crop growth stages ( Raza et al., 2022 ), which may result in crop failure ( Duchene et al., 2017 ).…”