The Effects And Mechanisms Of Exogenous NO And SA On The Drought Resistance Of Banana Seedlings

The effect of SNP, SA and c-PTIO on seedlings of banana cultivar "Brazil" (Musa AAA Cavendish) which dealing with soil water drought stress and PEG6000 was studied by means of biochemistry and plant physiology method in this paper. The results showed that:1. With the development of the soil water drought stress, relative water content of banana leaves decreased rapidly and the content of MDA and relative conductivity increased. The middle stress degree were reached when banana seedlings was suffered from soil drought stress for 7 days.2. The descent of leaf relative water content was delayed and by treatment with exogenous NO and SA.At the same time, the content of proline and the activity of superoxide dismutase (SOD) was increased and relative plasmalemma permeability and the accumulation of malondialdehyde was reduced. Both of 0.5 mmol/L SNP and 1.0 mmol/L SA could retard plants 3 days up to middle stress degree.3. Applied a concentration of SNP and SA could be relieved the osmotic stress of banana seedling leaves in vitro which caused by treatment with PEG-6000. In addition, the effects of SNP were inhibited significantly by c-PTIO under PEG stress, but effects of SA were lower than SNP. The effects of c-PTIO on SA-treated plants were relatively weak than that of SNP-treated plants suggested that SA could improve antioxidation system by NO generation under drought stress.