{"id":27505,"date":"2026-08-26T15:23:54","date_gmt":"2026-08-26T19:23:54","guid":{"rendered":"https:\/\/mmcereais.com.br\/2026\/milho\/radiacao-solar-e-peca-chave-no-enchimento-de-graos-do-milho\/"},"modified":"2026-08-26T15:23:54","modified_gmt":"2026-08-26T19:23:54","slug":"radiacao-solar-e-peca-chave-no-enchimento-de-graos-do-milho","status":"publish","type":"post","link":"https:\/\/mmcereais.com.br\/en\/2026\/milho\/radiacao-solar-e-peca-chave-no-enchimento-de-graos-do-milho\/","title":{"rendered":"Solar radiation is a key factor in the filling of corn kernels."},"content":{"rendered":"

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The availability of light during grain filling plays an important role in the productive performance of... corn<\/a>During this phase, the radiation reaching the leaves sustains photosynthesis and the production of compounds that will be directed to the ears of corn. When shading becomes excessive, photosynthetic activity decreases and can compromise the number of filled grains, the weight of a thousand grains, and the final productivity.\n<\/p>\n

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The amount of light available to the plant depends not only on climatic conditions. The distribution of plants in the field also affects the amount of radiation received. Very high populations, inadequate spacing, and uneven stands can intensify shading within the canopy, the structure formed by the leaves and other aerial parts of the crop.<\/p>\n

Corn has a C4 metabolism, a physiological characteristic that allows for high efficiency in the use of light. When it finds adequate conditions of radiation, water, and nutrients, the crop can maintain high rates of photosynthesis. Between fertilization and physiological maturity, the ears demand a large amount of the carbohydrates produced by the plant. During this period, the leaves that remain green play an essential role in the production of photoassimilates, compounds formed during photosynthesis and used, among other functions, in the formation of starch in the grains.<\/p>\n

When these leaves receive less light due to overcrowding or an unsuitable arrangement, net photosynthesis decreases. This can also reduce the amount of assimilates available for grain filling.<\/p>\n

Shading can accelerate leaf aging.<\/strong><\/p>\n

Solar radiation also affects the time the leaves remain active. When the plant population is suited to the hybrid's characteristics and the water and fertility conditions, the canopy can intercept a good portion of the light while maintaining better radiation distribution and aeration among the plants.<\/p>\n

This balance promotes the retention of green leaves for longer and prolongs the effective grain filling period.<\/p>\n

The scenario is different when plant density is excessive or when very close rows are adopted without the necessary adjustments. Under these conditions, shading mainly affects the leaves in the lower and middle parts of the plant and, in more intense situations, can also reach the upper leaves.<\/p>\n

One consequence is the acceleration of senescence, the natural aging process of leaves. With the premature reduction of functional leaf area, the plant loses its ability to produce the carbohydrates necessary to sustain grain filling for a longer period.\n<\/p>\n

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Population growth has its limits.<\/strong><\/p>\n

Using a higher number of plants per area does not necessarily mean increased productivity. Modern hybrids can tolerate higher populations than older materials, but there is a limit beyond which increasing density no longer results in higher yields.<\/p>\n

In situations of excessive density, the weight of grains per ear may decrease. The plant tends to direct resources towards maintaining the stem and the main ear, reducing the availability of assimilates per grain.<\/p>\n

Limited light can also promote flower abortion or compromise poorly fertilized grains, especially when shading occurs along with restrictions on water or nutrients.<\/p>\n

However, there is no single number of plants per hectare that can be considered excessive for all situations. The limit varies according to the hybrid, the production environment, water and nutrient availability, and other crop conditions.<\/p>\n

Hybrid architecture interferes with light distribution.<\/strong><\/p>\n

The position of the leaves also influences how solar radiation passes through the canopy. Hybrids with more upright leaves allow greater light penetration to the lower parts of the plant, reducing shading and favoring the use of radiation.<\/p>\n

Plants with more horizontal leaves, especially when grown in very close rows, can cause the space between the rows to close more quickly. This increases the risk of shading even in the relatively early stages of the crop.<\/p>\n

For this reason, population and spacing need to be analyzed together. The interaction between plant density, row spacing, and leaf architecture determines how light will be distributed within the crop.<\/p>\n

Main crop and second crop impose different conditions.<\/strong><\/p>\n

Light conditions also change throughout the agricultural calendar. In producing states such as Bahia, Goi\u00e1s, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Piau\u00ed, Paran\u00e1, and Rio Grande do Sul, corn can be grown both in the main crop season and in the off-season crop season, often in succession to soybeans.\n<\/p>\n

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During growing season, solar radiation may be more abundant, but periods of increased cloud cover and excess water can reduce the plants' effective use of light.<\/p>\n

In the off-season, despite the possibility of high radiation, the shortening of the photoperiod at certain times and the greater occurrence of water stress can make it difficult to maintain green leaves during grain filling.<\/p>\n

These differences make it necessary to adjust the plant arrangement to the conditions of each environment. In areas with greater productive potential, with good water availability and balanced nutrition, it is possible to work with higher densities, provided that the hybrid has the capacity to withstand the increased density and that the spacing favors light penetration.<\/p>\n

In areas with a higher risk of water deficit during grain filling, more moderate plant populations can help reduce competition for light, water, and nutrients, preserving functional leaf area for longer.<\/p>\n

The sowing season affects the period of greatest demand for sunlight.<\/strong><\/p>\n

The timing of crop planting also influences the conditions encountered during the reproductive period. Corn has its greatest light requirement between tasseling and the end of grain filling.<\/p>\n

Depending on the region, sowing too late can cause this phase to coincide with months of lower solar radiation or higher cloud cover. Under these conditions, the ability to complete grain filling may be reduced even when the plant population is adequate.<\/p>\n

Planting in a way that brings the period of greatest crop demand closer to times with greater availability of radiation tends to favor grain weight and productivity stability.<\/p>\n

However, there is no single planting window suitable for all regions. Radiation conditions, climate, and water availability vary between different states and production systems.<\/p>\n

Management should take into account the conditions of each crop.<\/strong><\/p>\n

The efficient use of light in corn results from the interaction between climate, plant population, spacing, hybrid architecture, and planting time. Therefore, planning should not consider any of these factors in isolation.<\/p>\n

The choice of plant arrangement should take into account the characteristics of the hybrid, the area's productivity history, the expected availability of water, the nutritional conditions, and the period in which the crop will go through the reproductive phase.<\/p>\n

When plant population and spacing are adjusted to environmental conditions, the crop can improve radiation interception, maintain green leaves for longer, and support grain filling. Conversely, excessive plant density and internal shading increase competition and can reduce the amount of carbohydrates delivered to the ears.<\/p>\n

Decisions regarding plant population, spacing, and planting time should consider research recommendations for each region and the specific conditions of the property, with the guidance of an agricultural engineer.<\/p>\n<\/p><\/div>\n

THE MM Cereais<\/strong> works with the best grains on the market and also keeps you up to date with the latest news and analyses on agribusiness.
\nDon't forget to follow our social networks.<\/em><\/h6>\n

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A disponibilidade de luz durante o enchimento de gr\u00e3os tem papel importante no desempenho produtivo…<\/p>","protected":false},"author":1,"featured_media":27506,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[223],"tags":[244,248,255,249,254,250,246,247,256,245,253,252,251],"class_list":["post-27505","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-milho","tag-agrolink","tag-agrotoxicos","tag-artigos-tecnicos","tag-classificados","tag-colunistas","tag-compra","tag-cotacoes","tag-defensivos","tag-eventos","tag-noticias","tag-precos-agricolas","tag-previsao-do-tempo","tag-venda"],"_links":{"self":[{"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/posts\/27505","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/comments?post=27505"}],"version-history":[{"count":0,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/posts\/27505\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/media\/27506"}],"wp:attachment":[{"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/media?parent=27505"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/categories?post=27505"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mmcereais.com.br\/en\/wp-json\/wp\/v2\/tags?post=27505"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}