Phenology and Biomass Production of Adapted and Non‐Adapted Tropical Corn Populations in Central Iowa

Abstract

Biofuel production in the midwestern United States has largely focused on corn (Zea mays L.) grain for ethanol production and more recently, corn stover for lignocellulosic ethanol. Tropical corn refers to corn adapted from tropical regions. Growing tropical germplasm in temperate environments is not attractive for grain yield, but shows promise for biomass production through taller and more vigorous plants with thick stems and long leaves. The comparison between tropical corn populations and their temperate adapted counterparts with a focus on biomass production has not yet been explored under Iowa growing conditions. This study refines the accuracy of the leaf collar method, and characterizes the adaptation of the populations by evaluating crop development and biomass production. Therefore, field trials were established in central Iowa during the 2014 and 2015 growing seasons. Adapted and non-adapted versions of three populations, Tuxpeño, Suwan, and Tuson, were planted at three dates to evaluate their phenology and potential for biomass production under midwestern U.S. conditions. Plant height correlated well with vegetative development and total biomass. Adapted tropical corn had advanced grain development, while non-adapted tropical corn had advanced vegetative development and greater biomass yield. Non-adapted tropical corn flowered later, had 22% greater total biomass on average (4.6 Mg ha -1 greater than adapted), and had 43% greater non-grain biomass on average, up to 20 Mg ha -1 (6 Mg ha -1 greater than adapted), while adapted populations yielded more grain. Non-adapted tropical corn has a high potential as feedstock for Gen2 biofuels in central Iowa. A gronomy J our n al • Volume 110 , I ssue 1 • 2 018 1 C orn from tropical regions is highly photoperiod sensitive; therefore, it fl owers later when grown at temperate latitudes than when grown at tropical latitudes (Ellis et al., 1992). Photoperiod sensitive corn is a short-day plant, and tassel initiation time is decreased when grown under short day conditions. Tropical corn continues vegetative growth when days are longer than the critical photoperiod and may therefore accumulate more biomass than temperate corn when grown at higher latitudes. Th e potential of tropical corn has been evaluated mainly for grain production (King et al., 1972;Oyervides-Garcia et al., 1985;Edmeades et al., 1993;Pulam, 2011). Due to lower grain yields compared to U.S. Corn Belt hybrids, tropical populations have been adapted to be a better source of germplasm for U.S. Corn Belt conditions (Hallauer, 1999;Teixeira et al., 2015).Tropical corn populations adapted to central Iowa conditions include Tuxpeño, Suwan, and Tuson. For the Tuxpeño adaptation, Hallauer (1994) formed a composite with three sources from Mexico (one short plant height, one "Puccinia sorghi resistant", and one early fl owering tropical population). For the Suwan adaptation, Hallauer (1994) used a population developed in Th ailand and selected in it for early fl owering. For the Tuson adaptation, H...

Biomass Production and Composition of Temperate and Tropical Maize in Central Iowa

“…These studies have found morphometric variables are better able to predict biomass outcomes during both vegetative and early reproductive growth. Overall, this study and previous ones suggest that plant height could be an indicator of non-grain and total biomass production [7].…”

“…In addition, multiple non-adapted tropical germplasm have been grown in temperate conditions. Prior studies have shown tropical maize has significant vegetative growth and plant height when grown under temperate conditions [7]. This is favorable when exploring the potential of a germplasm to produce high amounts of non-grain biomass.…”

Biomass, yield and competitiveness of maize and bean crops in an association system

“…In this environment, the SM(o) reached 0.47, while in Gama the HI fell to 0.37. The results reported by Infante et al (2018) show that the HI in maize is equivalent to 0.36 and when the plants adapt to the environment, the HI oscillates between 0.30 and 0.41.…”

“…In Gama, the higher yields were found in HB(o) and IB(o), with 22.55 and 20.90 pods per plant at 159 DAS, respectively (Figure 2A). According to Infante et al (2018), when cultivars adapt to the environment, they increase grain production and decrease biomass production. In this case, beans have adapted better to Simijaca than to Gama.…”

Variabilidad del germoplasma de maíz (<i>Zea mays</i> L.) en Argentina: La aptitud forrajera asociada a la producción de bioetanol lignocelulósico

“…Comparado con el germoplasma templado, los genotipos tropicales suelen ser más altos, tienen mayor área foliar, tallos más gruesos y mayor producción de biomasa aparejado de una mayor estructura de sostén y una menor partición a grano (Giaveno y Ferrero, 2003;Muttoni et al, 2013;Infante et al, 2018). El contenido de FDA fue mayor en M2 que en M1 (Figura 12), esto coincide con varios autores (Lewis et al, 2004;Darby y Lauer, 2002;Hansey et al, 2010) quienes asocian su incremento a los procesos de senectud que sufre la planta durante el llenado de granos.…”