Effect of spent wheat straw on growth, growth hormones, metabolism and rhizosphere of cucumis sativus

The effect of wheat straw added to the soil as a raw straw [rs] and spent straw [ss] form [after being treated by oyster mushroom, Pleurotus floridanus] on the growth of cucumber plants [Cucumis sativus] was studied. In addition to microbial biomass of the rhizosphere and soil chemical properties. The response of cucumber plants treated with either [rs] or [ss] at concentration 1.0 percent and 0.2 percent respectively exhibited the best growth. There were an increase in fresh weight, dry weight, number of leaves, leaf area, photosynthetic pigments, main growth regulators [auxins, gibberellins and cytokinins] and some metabolites [carbohydrates, nitrogenous compounds, nucleic acid] and some minerals [K, Na and Ca] than in control plants, whereas the highest concentration [2.0 percent] of both types of straw suppressed these parameters. The analyses of either raw or spent straw revealed that, they contained considerable amounts of carbon, nitrogen, minerals and hormones. This lead to a change in the chemical composition as well as the microbial biomass in the soil. On the other hand, spent straw contained higher values of phenolic compounds than in raw straw as a result of lignin decomposition by Pleurotus floridanus which resulted to decrease the growth of cucumber. This was related to the stimulation in IAA oxidase

Plant growth, metabolism and adaptation in relation to stress conditions. XX. comparative effects of salinity on growth, metabolism and yield of three different bean plants

The effects of increasing NaCl concentrations [up to 1.5 percent being equivalent to 255 mM] on growth, yield and chemical composition of three different bean plants [Glycine max var. Crowford, Phaseolus vulgaris var. Giza 3 and Phaseolus vulgaris var. Contender] have been studied. Thus, all growth, development and yield parameters appeared to remain unaltered, accelerated or, in most cases, suppressed with particular significance. These changes appeared to be dependent on [1] the concentration of NaCl, [2] the plant tested and 3 the stage of plant growth and development. Teatrnent of the three bean plants with various salinity levels led to marked changes in the total amounts and in the relative composition of carbohydrate and nitrogen pools in shoots and the yield of beans. Variable changes were also obtained for the contents of oil as well as for the constituent saturated and unsaturated fatty acids. Moreover, the results of seed protein fractionation showed marked changes in the composition of polypeptides with a wide range of molecular weights. In conclusion, the following sequence of plants: soybean > kidney bean > bush bean appears to be displayed with respect to the degree of tolerance to salinity

combined effects of salinity and Ca [No3] 2 of KNO3 on growth and metabolism of phaseolus vulgaris

Additional Ca[NO3]2 or KNO3 to media salinized with NaCl appeared to improve growth and metabolism of Phaseolus vulgaris. Ca2+ and K+ concentrations increased in both shoots and roots with increasing their concentration in the medium whereas Na+ concentration was greatly decreased. With the decrease in internal Na+ concentration, the concentrations of reducing sugars, sucrose and in consequence total carbohydrates were increased. However, the increase in sugars at 60 mM K+ was greater than at 40 mM Ca2+ although the internal Na+ concentration was similar in shoots [0.2 mmol/g dry weight]. Also, protein concentration was greatly increased, whereas soluble nitrogenous compounds were decreased with increasing either Ca2+ or K+ in the salinized medium. This suggests that Ca2+ and/or K+ as nitrate salts could be added to NaCl salinized media to overcome the deleterious effects of salinity on growth and ameliorate the productivity of leguminous crop plants