The effects of aqueous solutions applied as foliar spray and drench applications of glycerol were tested on the ‘Chantenay’ carrot ( Daucus carota L.) family Apiaceae, corn ( Zea mays L.) family Poaceae, and spearmint ( Mentha spicata L.) family Lamiaceae under greenhouse conditions. Foliar sprays and drenches were administered to carrots at concentrations of 0, 1, 3, 5, 10, 25, or 50 ml·L ⁻¹ . Fresh weights, dry weights, and taproot diameter from carrot seedlings sprayed with a solution containing 5 mL·L ⁻¹ (50 m m ) glycerol increased 105.6%, 158.4%, and 53.8%, respectively, when compared with untreated carrots. Foliar sprays were administered to corn at concentrations of 0, 0.1, 0.3, 0.5, and 1 ml·L ⁻¹ and spearmint at concentrations of 0, 1, 5, and 10 mL·L ⁻¹ . Growth responses increased in corn and spearmint by using certain glycerol concentrations. Fresh weights, dry weights, and shoot length from corn seedlings sprayed with a solution containing 0.5 mL·L ⁻¹ (5 m m ) glycerol increased 83.5%, 154.6%, and 90.9%, respectively, when compared with untreated corn. Fresh weights, dry weights, and shoot length from mint plants sprayed with a solution containing 5 mL·L ⁻¹ (50 m m ) glycerol increased 46.6%, 68.7%, and 102.5%, respectively, when compared with untreated plants. Glycerol applications can stimulate growth responses in diverse plant species.

Properties of High Density Polyethylene – Paulownia Wood Flour Composites via Injection Molding

Studies aimed at improving the tensile, flexural, impact, thermal, and physical characteristics of wood–plastic composites composed of Paulownia wood flour derived from 36-month-old trees blended with polypropylene were conducted. Composites of 25% and 40% w/w of Paulownia wood were produced by twin-screw compounding and injection molding. Composites containing 0–10% by weight of maleated polypropylene were evaluated and an optimum maleated polypropylene concentration determined, i.e., 5%. The particle size distribution of Paulownia wood filler is shown to have an effect on the tensile and flexural properties of the composites. Novel combination composites of dried distiller’s grain with solubles mixed with Paulownia wood (up to 40% w/w) were produced and their properties evaluated. Depending on the composite tested, soaking composites for 872 h alters mechanical properties and causes weight gain.