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The effects of different fertilizers and biofertilizers on crop production to increase plant growth, improve quality and yield components (dry leaves yield, leaf protein, and stevioside) of crops has been extensively studied. However, the combination of both types of fertilizers have rarely been investigated. To explore the effect of different fertilizers and biofertilizers on stevia plant, a two-year field experiment was conducted to investigate the growth response of stevia plants under the influence of nitrogenous fertilizers (NFs) and effective microorganisms (EM). The experiment was laid out in a split-plot design, with EM as the main plot factor (−EM and +EM) and NFs as the subplot factor [control, chemical NFs (Ch-N) and organic NFs (Org-N)]. The results showed that, plants treated with EM and Org-N showed 2-, 2.2-, 2.4-, 2.5-, 3.3- and 3-fold increases in plant height, number of branches, total leaf area, plant fresh weight, plant dry weight and leaf dry yield, respectively, compared to untreated plants. Similarly, plants receiving EM along with Ch-N showed 1.86-, 1.7-, 2.2-, 2.12-, 3-, and 2.72-fold increases in the same traits. Total chlorophyll, protein, N, P, K and sativoside contents were increased by 88.8, 152, 138, 151.5, 43 and 137.5% when EM and Org-N were applied to stevia plants. Application of EM together with Ch-N increased these properties by 0.5, 127.7, 115, 216, 42.6 and 83.8%, respectively in the same traits. Overall, the combined application of NFs and EM improved growth, yield and nutrient accumulation in stevia plants.

Silk cotton seed kernel oil is given as a new source for methyl ester synthesis. Crude silk cotton oil was used as feedstock raw materials for methyl ester production using dimethyl carbonate as solvent and KOH catalysis. The maximum methyl esters yield produced as 97% with a kinematic viscosity (4.25 ± 0.2 5 mm2/sec) was reached at 80 °C by boiling a mixture of dimethyl carbonate (DMC) and oil mole ratio as 8:1 with 1.5 wt.% KOH catalyst (oil weight based ) for 75 min. The produced products were analyzed using gas chromatography-mass spectrometry to identify the methyl esters. The properties of the methyl esters from silk cottonseed kernel oil produced met the specifications of ASTM for methyl esters. The kinetics of the KOH-catalyzed transesterification of diglyceride (DG) and triglyceride (TG) with DMC were studied at 40 to 90 °C. We found that the activation energies for transesterification of diglycerides and triglycerides were 89.8 and 83.3 kJ/mol, respectively. The results showed that all the reaction variables studied had beneficial effects.