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  • Author or Editor: J. B. Valenzuela x
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Abstract

Aerial shoot growth and rhizome production of greenhouse grown lowbush blueberry plants were stimulated by foliar applications of 2-chloroethylphosphonic acid (Ethrel) at 50 and 100 ppm. Increasing concentrations of 500, 1000, 5000, and 10,000 ppm resulted in a correspondingly greater growth inhibition. At 100 ppm, Ethrel solutions without a surfactant caused growth promotion when compared to plants treated with Ethrel with a surfactant.

Open Access

To help develop fertilizer recommendations for organic vegetable production in Hawaii, the effects of organic amendments on basil yield were studied in two experiments. The treatments were synthetic nitrogen applied at 100 kg·ha–1 per crop, organic amendments applied at a rate of 8–160 MT·ha–1, and an unammended control. Each treatment was replicated four times in a RCB design. In the first experiment, chicken manure was the organic amendment at 8 MT·ha–1 with a single basil variety grown. In the second experiment, conducted at the same location immediately following the first experiment, the organic amendment was locally produced compost (0.3% N) applied at 40 and 160 MT·ha–1 with three basil varieties grown. Data taken included soil fertility levels before and after experimental completion, marketable yields recorded weekly over 5–10 weeks, and tissue N and nitrate sap analysis measured at two to three different plant growth stages. In the first experiment, treatments receiving chicken manure or synthetic N showed similar yields (256–289 g/plant), which were significantly greater than the control (197 g/plant). Tissue N levels were greatest in the synthetic fertilizer treatment (4.9%) and lowest in the control (4.5%). In the second experiment, there was a differential response by varieties to treatments with respect to yields. Yields from the compost treatments (292–700 g/plant) were equal to or greater than those receiving synthetic fertilizer (320–651 g/plant) and were generally greater than the control (324–532 g/plant). Tissue N levels were greatest in plants receiving synthetic fertilizer (4.6% to 4.7%) and lowest in the control (4.3% to 4.4%). A positive correlation was found between lab tissue N levels and nitrate sap analysis determination.

Free access