Physiological responses in nutrient solution treated phaseolus vulgaris plants grown on calcareous soil

ABSTRACT

The results of this work showed that the observed responses of plant growth and some related physiological aspects were dependent on [1] the concentration of CaCO 3 in soil, [2] the organ of the plant. Thus, the results of this work could be summarized as follows - 1. The growth criteria of shoot [length, dry weight, area of fully expanded leaf and the total leaf area] were highly significantly decreased in response to the high levels of CaCO 3 treatments [40, 60 and 80 percent] during the plant growth. 2. Soil application of different levels of CaCO 3 induced appreciable decrease in total auxins, gibberellins and cytokinins and caused accumulation of abscisic acid. 3. The different levels of CaCO 3 induced different decreases in chlorophyll a, chlorophyll b, and total pigments with respect to the recorded values for control. Also, the results showed that the high concentration of CaCO 3 [60, 80 percent] highly significantly increased the carotenoids content while the lower levels of CaCO 3 [10, 20 and 40 percent] non-significantly affected such photosynthetic pigment. The results also showed a reduction in 14CO2-photo-assimilation in response to the different levels of CaCO3, the magnitude of reduction in the soluble, insoluble, total photosynthates and soluble/insoluble ratio photosynthates was more pronounced with the increase in the concentration of CaCO3 4. It has found that uptake and transport of Ca [++], Na [+] and K [+] ions under soil application of CaCO 3 are closely related to the individual parts of Phaseolus vulgaris plants