Interrelationship between potassium rates and the efficiency of Bt genes in the control of Spodoptera frugiperda

Abstract

The objective of this work was to identify the effect of potassium rates on Bt transgenic resistance and damage caused by Spodoptera frugiperda in corn plants at different developmental stages. The experimental design was a randomized complete block in a 3x6 factorial arrangement, with three potassium rates (0, 45, and 90 kg ha-1) and six corn hybrids (20A55Hx, 30A77PW, AG1051, MG652PW, NS90VTPro2, and NS92VTPro), with three replicates. The hybrids were evaluated through the analysis of canonical variables. With low potassium rates, the effectiveness of the corn hybrids in controlling the S. frugiperda caterpillar decreases in the different phenological stages. The use of the Bt technology is more efficient under an adequate potassium rate of 90 kg ha-1 KCl.

Interrelation between Nitrogen Doses and the Efficiency of Bt Genes in the Effective Control of Spodoptera frugiperda

“…According to Nóia Júnior & Sentelhas (2019), the complex interaction of precipitation, solar radiation, air temperature, and other meteorological parameters, in addition to the interaction of the genotype with the environment, make it challenging to determine the best sowing date in soybean succession in different Brazilian producing regions, mainly due to problems caused by the effects of El Niño or La Niña. This influence of precipitation and temperature fluctuation was also verified by Faria et al (2023), when evaluating effect of potassium rates on Bt transgenic resistance and damage caused by Spodoptera frugiperda in corn plants at different developmental stages eand detected that it can alter the performance of hybrids and favor herboria by weakening the plant.…”

“…In this case, the AG1051 hybrid may have greater tolerance because it is a double hybrid and possibly greater capacity to withstand attacks and less variation in its performance, compared to single hybrids, with the presence of proteins and greater uniformity and also vulnerability. According to Faria et al (2023), at low levels of potassium, the effectiveness of corn hybrids decreases in controlling Spodoptera frugiperda and the presence of more Cry proteins is not capable of preventing attacks and is only efficient at the appropriate rate (90 kg ha -1 KCl).…”