RESPONSE OF SUBTROPICAL MAIZE HYBRIDS TO PLANT DENSITY

Abstract

In maize (Zea mays L.) crop plant density is an important component of grain production. This research aimed to study the response of grain yield and agronomic characteristics of five experimental maize hybrids when varying plant density. The hybrids were planted along with two checks at 65, 75 and 90 thousand plants ha-1 using a randomized complete blocks design with three replications with an split-plot arrangement where the whole plot included plant densities and the split-plot the hybrids. The experimental unit consisted of four rows and the useful plot included the two central rows. The evaluation was carried out at Peña del Panal, Michoacan, Mexico under irrigation, and at Tepatitlán and San Miguel Cuyutlán, Jalisco Mexico under rainfed conditions. Plant and ear data were registered and combined statistical analyses were performed across localities. The yield of hybrids was different as plant density increased. Hybrids HE-48, HE-46, HE-15A and H-377 increased grain yield as the plant density increased; the performance of hybrid H-377 was different when increasing the plant density, at 65 thousand plants ha-1 it had low grain yield and at 90 thousand it reached its maximum yield. Hybrids HE-48 and HE-15A had high performance in both low and high plant density. Grain yield as a function of plant densities is an important factor to consider for the profitability of the crop, especially in rainfed maize plantings, since under those conditions the grain yield decreased as the plant density increased.