Co-regulation Of ear growth and internode elongation in corn

Abstract

Ear is the harvest part of corn (Zea mays L.) and we are interested in studying its growth and development in our effort in corn yield improvement. In our current study, we examined the relationship between ear growth and internode characteristics using different approaches. Correlations between stem growth rate and number of ears per plant (prolificacy) were assessed among several genotypes. Internode elongation of 2 genotypes was modified by plant hormones and by population density manipulations. Among the 7 genotypes examined that have different prolificacy levels, there was a general correlation of slower stem elongation at middle growth stages and larger ear number. When the internode elongation was enhanced by application of gibberellic acid (GA), ear growth was suppressed; and when a GA synthesis inhibitor uniconazole was applied at early stages, internode length was reduced and ear growth was promoted in terms of both ear size and visible ear number at silking stage. Higher population density caused longer internodes and fewer ears per plant and the effect of lower density was the opposite. Our results suggested that internode elongation in the middle section of corn plants was linked to suppression of ear development in corn.

Compensation of Corn Yield Components to Late‐Season Stand Reductions in the Central and Northern Great Plains

“…At Garden City, compensation in the ears plant -1 yield component occurred as late as the V11 growth stage when under conditions of 75% stand removal (Table 1). Xu et al (2004) reported that even for non-prolific hybrids, the ears plant -1 yield component did not become completely fixed until between V11 and R2.…”

Maize harvest index and water use efficiency can be improved by inhibition of gibberellin biosynthesis

“…In contrast, Xu et al. () found an increase in cob size when UCZ was applied at early growth stages, pointing to the impact of application time on yield performance. The application of PAC always resulted in shorter internodes and reduced plant height (Dale & Drennan, ; Iremiren, Adewumi, Aduloju, & Ibitoye, ; Khalil & Rahman, ).…”

“…Hormone levels, particularly of GAs in maize, affect flower sexuality (Bortiri & Hake, ; Irish, ). High levels of GA induce feminine characteristics, whereas in the semi‐dwarf mutants with low GA levels, masculine structures are favoured (Irish, ; Rood, Pharis, & Major, ; Schluttenhofer, Massa, & Mitchell, ; Xu, York, Miller, & Cheikh, ). The abnormalities in maize flowers could be overcome by a non‐constitutive modification of GA concentrations in the vegetative tissues while leaving GA in the reproductive organs unaffected (Xu et al., ).…”

Response of Maize Grown Under High Plant Density; Performance, Issues and Management - A Critical Review

“…High plant density is a good strategy to obtain high yield [7,8] to meet the current and future food necessities of high population and their rising dietary needs [9]. Improvement in corn yield is dependent on its genetic characteristics, morph-physiological behaviour and its interaction with the environment [10]. Increasing the population density of plants is an agronomical practice that has continuously been studied for maize crops (Table 1).…”