Simulating Potential Kernel Production in Maize Hybrid Seed Fields

Abstract

In maize (Zea mays L.) hybrid seed production, achieving the optimum seed yield per unit land area often is based on limited information about the quantity of pollen shed by the male and practical experience synchronizing pollen shed by the male inbred with silk emergence by the female inbred. We recently reported that kernel production per hectare could be simulated fairly accurately under pollen‐limited conditions from simple measures of pollen shed and silking dynamics. The objective of this study was to determine whether a simple mechanistic description of the flowering dynamics of male and female inbreds could be used to simulate and optimize kernel production in seed production fields. We estimated kernel production on the basis of flowering dynamics in six commercial seed fields located near Washington, IA, in 2002, which differed in the quantity of pollen production and silk emergence. In all cases, the fields were managed and harvested by standard seed industry methods. Harvested kernel number varied from 8.4 to 23.1 million kernels per female hectare. Simulated kernel number was closely correlated with these measured values (r2 = 0.98). This result indicates that relative differences in kernel production can be assessed directly from inbred flowering dynamics. Examples are provided to show how inbred management can be modeled to optimize harvested kernel number for a given inbred pair. Model simulations, however, overestimated harvested kernel number by 11%, on average, which implies that other plant factors, such as pollen viability, prolificacy, pollen capture by the canopy, or kernel abortion in response to leaf removal during detasseling might have limited kernel production across the six seed fields. Information about these variables can be incorporated readily into the kernel set model to improve its accuracy. This study indicates that kernel production in a hybrid seed field can be simulated from simple measures of inbred flowering dynamics. The model is a useful tool for optimizing harvested kernels for an established inbred pair or for defining initial management protocols for new combinations of inbreds.

Effect of Male Planting Date and Female Plant Population on Hybrid Maize Yield and Evaluation of Use of Hybrid-Maize Simulation Model for Grain Yield Estimation in Hybrid Maize Seed Production

“…This was contrary to literature : Fonseca et al (2004) using simulated data reported that delaying pollen shed from the original 1.2 to 3 days resulted in nearly 68% of the silks being pollinated causing a 23% increase in potential kernel yield. If the interval were increased to 5 days, potential kernel yield would be increased by about 38%, indicating the potential of increasing GY by late planting of male line.…”

Scheduling Irrigation as a Water Saving Practice for Corn (Zea mays L.) production in Iraq

“…The reason for this due to prolong irrigation intervals which puts the plant under water stress, and accordingly causes low growth rates and reducing of leaf area and increasing the possibility of stomata resistance for CO 2 gas exchange and it seclusion, therefore Low carbon synthesis process and lower metabolism take place, this process leads to reducing the grain yield. These results agreed with (36,37).…”

Maize pollen deposition in relation to distance from the nearest pollen source under common cultivation - results of 10 years of monitoring (2001 to 2010)

“…For example, turbulence, heat-induced up-drifts, and the stronger winds that typically occur during the maize flowering period in summer can enhance the release and dispersal of maize pollen. These factors correlate with the warm, windy, dry weather conditions during the daytime that trigger the maize pollen release [29,31,32,39,40,44,45].…”

“…Depending on the variety and growing conditions, each plant releases from approximately 5 million to 50 million pollen grains per season. Assuming an average density of 7 to 12 plants/m 2 , a 1-ha maize field sheds approximately 10 11 to 10 13 pollen grains over the flowering season [29][30][31][32]. Maize pollen is relatively large and heavy with a diameter ranging between 80 and 125 μm.…”