Sustainable effects of diatomite on the growth criteria and phytochemical contents of Vicia faba plants

Abstract

Recent scientific findings proved that silicon feeding will provide benefits to plant growth and yield depending on the source of Si, the mode of application , the concentration used, the plant species , the mode of action and the biotic or abiotic factor involved. To better understand the intrinsic properties of Si , this work was conducted using a series of diatomite (diatomaceous earth)at rates of 0,2.5, 5 and 10 g/kg soil, to look into the most subtle changes in the growth , yield, metabolism, electropharetic protein and isozyme pattern of faba bean ( Vicia faba) plant. Indeed, diatomite-treated plants displayed an over all better morphological increments expressed as shoot and root length , number of leaves and pods/ plant, fresh and dry weights of shoots and roots and physiological activity expressed as chlorophyll a,b and total pigments , total soluble sugars (TSS) and total sugars (TS), photosynthetic rate, leaf stomatal conductance, % of leaf relative humidity ( %LRH), net intercellular carbon dioxide (∆CO2), total nitrogen (TN) and total soluble nitrogen (TSN) and the concentrations of phosphorus (P), potassium (K), calcium(Ca) and magnesium (Mg) than non-treated faba bean plants . Furthermore, diatomites (86-89 % SiO2) induced and restored ten electrophoretic protein bands which confirmed their significance as an algal manure in accelarating the gene functions to perform, in an elevated rate, new silence genes to operate thus expressing new protein profiles. Soil fertilization by diatomites induced four esterase ( EST), three peroxidase (POD), two catalase (CAT) and three acid phosphatase (ACP) isozyme polymorphic bands which were absent in the control plants .The intensity and density of these bands were significantly increased in response to diatomite treatment. The impact of diatomite is time-dependent as it became more effective while the experiment continued and increased in a dose-related manner . Reversibly, diatomites application showed negative response in the transpiration rate and the values of both carotenoids, sodium and iron. This study highlighted the fact that diatomites are important component of the production system and should not be ignored when attempting to attribute causes for below optimum production