Beneficial effects of bending maize plants at physiological maturity on lodging and on some pre-harvest grain quality parameters

Abstract

In the study, maize plants (cv. Aburotia) bent, just below the lowest ear, at 2 weeks before physiological maturity (PM), at PM, and 2 weeks after PM were compared with unbent plants for grain moisture content, cob infestation with insects (adults and larvae), grain mouldiness, grain yield per cob, and incidence of lodging. The bending and no bending treatments were applied in a randomized complete block design with three replications. Relevant weather records during the study period were provided by the Kumasi Meteorological Station. Grain moisture content, cob infestation with adult insects, and extent of lodging were, at harvest, significantly lower (P=0.05) in bent plants than in unbent ones. Among the bent plants, these parameters decreased with early bending. Moisture content of grains from plants bent 2 weeks before PM, at PM, and 2 weeks after PM, for example, were, at harvest, 23.3, 25.3, and 31.7 per cent, respectively, compared to 38.3 per cent recorded for unbent plants. Similarly, while only 1 - 2 plants/m2 lodged on plots with bent plants, an average of 5 plants/m2 lodged on plots with unbent plants. Cob infestation with stemborers/earworms, incidence of mouldiness, and grain damage per cob, also, were lower in bent than in unbent plants. Dry weight of marketable grains per cob was significantly highest (79.85 g/cob) in plants bent at PM and lowest (71.35 g/cob) in plants bent 2 weeks earlier. These results indicate that the bending over of maize plants has crop protection value. They further show that the ideal developmental stage to bend plants to combine the benefits of reduced pre-harvest grain moisture contents and field losses with maximum grain yield is at PM.


Ghana Jnl.agric. Sci Vol.31(2), 1998: 169-174