Photosynthetic Performance of the Imidazolinone Resistant Sunflower Exposed to Single and Combined Treatment by the Herbicide Imazamox and an Amino Acid Extract.
The herbicide imazamox may provoke temporary yellowing and growth retardation in IMI-R sunflower hybrids, more often under stressful environmental conditions. Although, photosynthetic processes are not the primary sites of imazamox action, they might be influenced; therefore, more information about the photosynthetic performance of the herbicide-treated plants could be valuable for a further improvement of the Clearfield technology. Plant biostimulants have been shown to ameliorate damages caused by different stress factors on plants, but very limited information exists about their effects on herbicide-stressed plants. In order to characterize photosynthetic performance of imazamox-treated sunflower IMI-R plants, we carried out experiments including both single and combined treatments by imazamox and a plant biostimulants containing amino acid extract. We found that imazamox application in a rate of 132 μg per plant (equivalent of 40 g active ingredient ha-1) induced negative effects on both light-light dependent photosynthetic redox reactions and leaf gas exchange processes, which was much less pronounced after the combined application of imazamox and amino acid extract.
Department of Plant Physiology and Biochemistry, Agricultural UniversityPlovdiv, Bulgaria; Centre for Environmental Sciences, Hasselt UniversityDiepenbeek, Belgium.
Dobrinka A
DA
Balabanova
Department of Biophysics and Radiobiology, Faculty of Biology, Sofia University Sofia, Bulgaria.
Momchil
M
Paunov
Department of Biophysics and Radiobiology, Faculty of Biology, Sofia University Sofia, Bulgaria.
Vasillij
V
Goltsev
Centre for Environmental Sciences, Hasselt University Diepenbeek, Belgium.
Ann
A
Cuypers
Centre for Environmental Sciences, Hasselt University Diepenbeek, Belgium.
Jaco
J
Vangronsveld
Department of Plant Physiology and Biochemistry, Agricultural University Plovdiv, Bulgaria.
Andon
A
Vassilev
chlorophyll fluorescence; imazamox; leaf gas exchange; plant biostimulants; sunflower