Agronomic Responses of Maize Hybrids to Row Spacing and Plant Population in the Summer and Winter Seasons in Brazil

Abstract

Brazil has two growing seasons for maize (Zea mays L.) production: summer and winter. The additional maize produced in the winter and the high-yielding opportunities in the summer season make it important to understand responses of maize hybrids to row spacing and plant population across the two annual Brazilian growing seasons. In the 2015 to 2016 summer season and the 2016 winter season, maize response to plant population, ranging from 60,000 to 90,000 plants ha -1 , was evaluated for three hybrids in 0.45-, 0.60-, 0.75-, and 0.90-m row spacing. Plant architecture traits, grain yield and yield components did not differ with row spacing, and their responses to plant population were not affected by hybrid type and/or row spacing. The DKB390PRO2 hybrid (single cross) demonstrated better grain yield performance in the summer, whereas the BG7049YH hybrid (three-way cross) had the highest yield in the winter. Plant and ear height increased linearly in response to plant population in the summer season, whereas other plant architecture traits, ear leaf chlorophyll concentration, and grain yield components decreased linearly with increasing plant populations in both seasons. There was a quadratic response in maize grain yield to plant population, and it was maximized with 78,688 plants ha -1 in the summer, and 71,206 plants ha -1 in the winter. Our results show preliminary evidence that regardless of row spacing, maize grain yield can be maximized with DKB390 hybrid (single cross) with 78,500 plants ha -1 in the summer, and BG7049YH hybrid (three-way) with 71,000 plants ha -1 in the winter season.

Employing factor analytic tools for selecting high‐performance and stable tropical maize hybrids

“…This season spans from September to December and is characterized by favourable weather for sowing depending on the climate zone (F. S. Dias et al., 2019). The second season or winter season usually has a shorter planting window and a higher risk of yield losses given the frequent occurrence of drought (F. S. Dias et al., 2019; Nóia Júnior & Sentelhas, 2019). Depending on the location, second‐season maize is grown from January to April (Nóia Júnior & Sentelhas, 2019).…”

Assessment of yield performance and stability of hybrids and populations of tropical maize across multiple environments in Southeastern Brazil

“…Currently, maize hybrids derived from crossing among inbred lines account for approximately 95% of the maize production area in Brazilian maize farmers, and even under unfavorable environments, most maize Brazilian growers have planted hybrids instead of other types of cultivars (Duarte & Kappes, 2015; Kist et al., 2021). Maize hybrids, especially single‐cross hybrids, have a narrow genetic base and are recommended for medium‐ to high‐yielding environments since they are very responsive to the environment and management practices (Carena & Wicks, 2006; Dias et al., 2019; Hallauer et al., 2010). However, the genetic potential of hybrids can be constrained by the occurrence of abiotic and biotic stress under tropical environments in Brazil and, consequently, under these limited environmental conditions, broad‐based maize cultivars may have equal or better yield performance and stability than narrow‐based cultivars (Dias et al., 2019; Faria et al., 2017; Fritsche‐Neto & Moro, 2017; Kutka, 2011).…”

“…Maize hybrids, especially single‐cross hybrids, have a narrow genetic base and are recommended for medium‐ to high‐yielding environments since they are very responsive to the environment and management practices (Carena & Wicks, 2006; Dias et al., 2019; Hallauer et al., 2010). However, the genetic potential of hybrids can be constrained by the occurrence of abiotic and biotic stress under tropical environments in Brazil and, consequently, under these limited environmental conditions, broad‐based maize cultivars may have equal or better yield performance and stability than narrow‐based cultivars (Dias et al., 2019; Faria et al., 2017; Fritsche‐Neto & Moro, 2017; Kutka, 2011). Although open‐pollinated varieties have a broader genetic base than any other maize cultivars, they can perform poorly under stress conditions, and thus population hybrids can be an interesting alternative for these conditions.…”

Experimental and influencing factors of corn stalk pulling force

“…Maize is one of the most widely planted and distributed crops globally, and the current top three countries in terms of maize acreage are China, the United States, and Brazil (Dias et al, 2019). According to the China statistical yearbook (2020), the planting area of maize in China is 41.26 million hm 2 .…”