The Effects of Furrow Depth in Alternate Row Planting on Germination and Yield of Spring Maize under Subsurface Drip Irrigation in North China Plain

Abstract

【Objective】 Subsurface drip irrigation (SD1) is a water-saving technique but difficult to keep the surface soil moist to ensure seed germination in drought-prone areas. Alternate row planting (AP) combined with the raised bed has been developed as an effective cultivation to moisten the surface soil. The purpose of this paper is to experimentally investigate the suitable furrow depth to improve seedling emergence and sustain crop yield. 【Method】 We took spring maize as an example and used the variety Xuntian 1102 as the model plant. The field experiment was conducted from May 2018 to September 2018 in the National Water-saving Irrigation Engineering Technology Research Center at Daxing, Beijing. The depth of the furrows was 0 (CK), 10 cm (H10) or 15cm (H15). In all treatments, the seeds were drilled to 5 cm deep from the soil surface and the irrigation amount prior to seedling emergence was 30mm, same in all treatments. During the experiment, we measured the changes in soil moisture, seedling emergence and the ultimate yield in each treatment. 【Result】 Alternate row planting combined with the raised bed significantly increased soil moisture at the drilling points to facilitate seed germination. Compared to CK, irrigating 35 mm of water prior to seedling emergence in H10 and H15 increased soil moisture in the region proximal to the seeds by 18.2% and 25.7%, respectively. The improved soil moisture increased the seedling emergence rate to more than 88% in both treatments, equivalent to a14.6% (H10) or 16.3% (H15) increase over the CK (P<0.05). The plant height and stem diameter both increased with the furrow depth, and the leaf area index in H10 and H15 was significantly higher than that in H0 (P<0.05). The ear length, ear diameter and ear number in H10 were 6.8%, 4.5% and 2.2% lower than those in CK, while the associated traits in H15 were 7.6%, 2.7% and 11.1% lower than that in CK. Apart from ear length, no significant difference was identified between H0 and H15. H10 gave the highest ear number and 100-kernel weight, the highest yield -12.98 kg/hm2 m which was13.4% and 7.5% increase compared to that in H0 and H15 respectively (P<0.05). 【Conclusion】 AP combined with SDI with the furrow depth being 10 cm was suitable cultivation for spring maize production in north China.

Keywords

• subsurface drip irrigation
• alternate row planting
• furrow depth
• maize germination
• yield