Comparative Yield and Photosynthetic Characteristics of Two Corn (Zea mays L.) Hybrids Differing in Maturity under Different Irrigation Treatments

Abstract

Effective irrigation strategies are of great significance for improving crop yields. There is an increasing concern that short-season corn hybrids are gradually being encouraged to plant in the North China Plain (NCP) with the development of mechanized grain harvesting, but the photosynthetic characteristics and productivity of short-season hybrids are not well documented. The objective of the study was to investigate the effects of different irrigation treatments on photosynthetic characteristics, dry matter accumulation (DMA) and photo-assimilate translocation (PAT/PT), grain yield (GY) and water productivity (WP) of two corn hybrids differing in maturity. In the experiment plots under the rainout shelter facility, short-season hybrid Denghai518 (DH518) and medium- and full-season hybrid Denghai605 (DH605) were grown under three irrigation levels (severe water stress, T1; mild water stress, T2; and non-stress, T3) by two irrigation methods (flood irrigation, FI; surface drip irrigation, SDI) in 2020 and 2021. The results indicated that non-stomatal limitation (NSL) was the main factor leading to the reduction in photosynthesis during the reproductive stage. Severe water stress significantly decreased net photosynthetic rate (Pn) and chlorophyll soil-plant analysis development (SPAD) value, resulting in lower DMA and GY. The contribution rate of vegetative organ photosynthate before flowering (CRP) decreased with the irrigation levels increasing. DMA, GY and WP of SDI increased by 16.23%, 21.49% and 51.31%, respectively, compared to FI. The yields of DH518 were 7.22% lower than those of DH605. The WP penalty for DH605 was attributed to a relatively larger ET. It suggested that applying the optimum irrigation level (T3) under SDI could increase DMA, GY and WP of summer corn in the NCP.

Producción de maíz forrajero con dos sistemas de riego y tres niveles de la evaporación aplicada

“…Algo semejante se observó en la variable RFS, en el que, la combinación sistema de riego por goteo subsuperficial -100% de evaporación fue superior a las demás (p< 0.05), con 14.85 t ha -1 y el rendimiento más bajo se obtuvo en el sistema de riego superficial -50% de evaporación con 8.67 t ha -1 (Cuadro 1). Valores similares fueron reportados por Yescas et al (2015); Wang et al (2022) quienes mencionan que los valores más altos de RFS se obtuvieron en el tratamiento con lámina de riego correspondiente al 100% de la evapotranspiración diaria con 14.78 t ha -1 y que el RFS en el sistema de riego por goteo, fue 16.24% superior al del sistema de riego por inundación.…”

Phenological and yield components response of major exotic maize varieties to different levels of soil bulk densities

“…Anjum et al (2018)and Li et al (2020) also reported a change in days to tasseling of maize with different bulk densities of soil. Wang et al (2022) also reported a negative correlation between hybrid maize yield with the increase in soil compactness. This could be because roots need to take up more nutrients for the plant, which were restricted by soil with high compaction due to higher bulk densities.…”

Water use characteristics of an early and late maturing maize hybrid using stable isotopes

“…Hybrids did not differ for E/ET during the whole growing season, but E/ET was higher in EM than in LM during the R3–R6 stage. The phenomenon was associated with the rapid advance of the leaf senescence process for EM hybrid during the R3–R6 stage, resulting in higher soil E via the reduction in percent ground cover (L. Wang et al., 2022). Soil E in maize constituted a similar proportion (almost 40%–55%) of total ET each season.…”