Effect of salt-stresses on the hormonal regulation of growth, photosynthesis and distribution of 14C-assimilates in bean plants

Abstract

The experiments were carried out to study the effect of salt-stresses and ABA on the growth, photosynthesis and translocation of assimilates in bean plants. It was planed to reduce the content of GA<sub>3</sub> and cytokinins and increase ABA content in salinized plants. The results show that salt-stress (NaCl and concentrated nutrient solution), reduce all the investigated processes in a different degree. NaCl-stress retarded most seriously growth of apical part and blades in contrast to 7-times concentrated nutrient solution decreasing mainly the rate of root and blade growth. Photosynthesis and <sup>14</sup>C-translocation of <sup>14</sup>C-assimilates were retarded more seriously by NaCl than by 7-times concentrated nutrient. solution. In the case of seriously stressed plants GA<sub>3</sub> and cytokinins (more effectively) reversed the ,negative effect of stress conditions both on the photosynthesis and on the <sup>14</sup>C-tramslocation. On the basis of the obtained results, it seemes that changes in the rate of investigated processes in salinized plants are due to hormonal disturbances which cause directly or indirectly retardation of photosynthesis and trans-location of assimilates.

Effect of Saline Water Irrigation on Sour Orange and Volkamer Lemon Seedling Rootstocks

“…Previous results showed that saline water decrease plant biomass and photosynthetic pigments due to the osmotic stress; one of the salinity effects on citrus rootstock seedlings caused by the total concentration of salt dissolved in the soil solution due to irrigation water quality, which affects the availability of free water (unbound) through physical processes (Starck and Karwowska, 1978). In the same line, salt tolerance in citrus is usually based on Cltoxicity than to Na + toxicity (Maas, 1993 andRomero-Aranda et al, 1998).…”

Ameliorative Effect of GA3 as Foliar Spray Treatment on Performances of Salt-Stressed Damsisa (Ambrosia maritima L.) Plants

“…In this respect, El-Sallami and Makary (2001) stated that salinity stress was accompanied by an increase in the content of phenolic compounds up to toxic concentration. Moreover, Stark and Karwowska (1978), working on bean plants and suggested that physiological changes occurring in plants under salt caused by hormonal imbalance. The obtained data also elucidate that Na was increased with increasing salinity levels in leaves and reverse was true for N, P and K concentration as compared with un salinized plants.…”