Corn is most susceptible to drought during flowering.

THE corn It exhibits greater sensitivity to water scarcity during the period from a few days before tasseling until the beginning of grain filling. The most critical phase comprises approximately 10 to 15 days before tasseling until 10 to 15 days after the emergence of the style and stigmas.

During this period, the formation and opening of male flowers, the emission of ear silks, the release of pollen, and the fertilization of ovules that will give rise to the grains occur. Therefore, water deficit at this stage can directly compromise the number of grains per ear.

Lack of water can cause a mismatch between tasseling and the emergence of silk-like patterns, premature drying of the hairs, and reduced fertilization. Even short periods of stress can cause significant production losses.

Before flowering, lack of water can also affect the crop. At emergence, it can cause stand failures and unevenness. During vegetative growth, prolonged deficits reduce leaf area and root development, leaving the plant more vulnerable in subsequent stages.

After fertilization, during grain filling, water demand remains high. Drought can reduce the weight of a thousand grains, accelerate leaf senescence, and decrease commercial yield, although the sensitivity is less than during flowering.

Planting planning should consider rainfall distribution, soil type, hybrid cycle, and production system. The goal is to avoid, whenever possible, flowering coinciding with periods of higher drought risk.

Among the practices mentioned to reduce the impacts of water scarcity are adjusting the sowing season, choosing hybrids, managing the soil, adjusting the plant population, and using supplemental irrigation when available.

Thus, the period between tasseling, silk emergence, and fertilization concentrates the greatest risk of losses due to water deficit in corn, as it is precisely the phase in which the number of grains is determined.