Effect of mineral nutrients and mefluidide treatments on chilling tolerance of pepper seedlings

Abstract

Pepper (Capsicum annum.) seedlings were used to study the effect of CaCl<inf>2</inf>, MgCl<inf>2</inf>, KC1 and mefluidide on tolerance to chilling stress. Seedlings were sprayed with the solutions of these chemicals one day prior to chilling exposure at 4°C in growth chambers with 12 hours photoperiod and 75% relative humidity. The results obtained showed that visual symptoms of chilling injury were less in treated than non-treated chilled plants. Chilling stress causes an increase in electrolyte leakage and a decrease in leaf water potential, these effects were significantly reduced by all of these treatments. Also, treated chilling plants showed lower transpiration rate which helped plants to maintain high leaf water potential during chilling stress. Total chlorophyll content was higher for treated than non-treated chilled plants. Post stress observations showed that treated plants grew better and more taller than non-treated plants, and they had higher yield per plant at the end of the experiment. The results indicate that these treatments reduce chilling injury by improving plant water status during chilling which can increase plant tolerance to low temperature stress. Chemical name used: Mefluidide: N-[2,4 dimethyl-5 [(trifluromethyl) sulfonyl] amino] phenol acetamide)].