Physiological aspects of corn plants related to mesotrione herbicide selectivity

• Published in: Australian Journal of Crop Science Vol. 10; no. 8; pp. 1158 - 1163
• Main Authors: Freitas, Ismael Lourenço de Jesus, Rodrigues, Weverton Pereira, Freitas, Silvério de Paiva, Freitas, Jalille Amim Altoé, Amim, Reynaldo Tancredo, Junior, Antonio Teixeira do Amaral, Campostrini, Eliemar
• Format: Journal Article
• Language: English
• Published: Lismore, N.S.W Southern Cross Publishers 2016
• Subjects: Corn; Effect of herbicides on; Photochemistry; Plants; Yields
• ISSN: 1835-2693; 1835-2707
• DOI: 10.21475/ajcs.2016.10.08.p7787

The objective of the present study was to assess the physiological aspects related to the activity of mesotrione herbicide at different doses in corn plants. The experiment was performed, in a greenhouse, on UENF 506-8 hybrid grown in 12 L pots with substrate (2:1 sand and clay). A randomized complete block design in a 3 x 5 factorial scheme, with four replications was used. Plants at fourth leaf stage were exposed to three doses (0, 0.15 and 0.30 kg ha-1) of herbicide mesotrione. Three, four, five, six and 13 days after application (DAA) of herbicide mesotrione gas exchange and chlorophyll a fluorescence (considering a JIPTest analysis) were measured. Plant height (PH), leaf area (LA), canopy (CDM) and root dry matter were measured at 28 DAA, when plants were at V12 stage and ca. 85 to 90% grown of its total area. The results showed that UENF 506-8corn hybrid was remarkably tolerant to dose of 0.15 Kg ha-1 without deleterious effects on photochemistry and biochemistry path way, maintaining the values of several JIPTest parameters and gas exchange. However, decreases in photosynthetic rate, stomata conductance, and transpiration and several JIPTest parameters were observed when the plants were exposed to dose of 0.30 kg ha-1 although there was no harmful damage on most of the growth parameters. However, dose of 0.15 Kg ha-1 should be recommended since dose as high as 0.30 kg ha-1 caused decrease in CDM.