Enhancement of Growth, Flowering and Corm Freesia Hybrida Plant via Rice Organic Residue Application and Chelated Zinc Spray

A pot trial was conducted to identify the effect of adding rice organic residues (ROR) to the potting soil and spraying chelated zinc (CZn) on the growth, flowering, and corm characteristics of the Freesia hybrida plant. An RCBD experiment was adopted with two factors and three replicates. ROR comprised three levels (0, 4, and 8%), and CZn included three concentrations (0, 20, and 40) mg.L−1. The findings revealed that applying ROR at 8% and spraying CZn at 20 mg.L−1 significantly increased leaf number, shoot dry weight, total chlorophyll content in fresh leaves, and total soluble carbohydrate content in dry leaves (6.66 leaves. plant−1, 8.76 g DW, 48.79 mg.100 g−1 FW, and 1.50 g DW) respectively. Also, the same treatment combination realized significant results for the number of florets per inflorescence, floret diameter, floret vase life, number of corms per plant, and corm diameter by (12.85 florets. inflorescence−1, 7.03 cm, 8 days, 3.66 corms. plant−1, and 2.33 cm) consecutively. Further, adding ROR at 8% and spraying CZn at 40 mg.L−1 significantly increased the number of inflorescences (5.33 inflorescences. plant−1) and inflorescence length (39.10 cm).

Effect of Pre-plant Phosphate Charge and Leaching on Phosphorus Longevity in Soilless Substrate1

There is little information addressing the impact of quantity of pre-plant phosphate charge in soilless substrate and leaching during production on soluble phosphate longevity when post-plant phosphate is omitted. Two experiments were conducted growing Petunia ×hybrida ‘Primetime White' seedling crops over a 42-d period in a sphagnum peat moss-perlite substrate. Phosphate-phosphorus (P) charge levels of 0.03, 0.06, 0.12, and 0.18 kg.m−3 (0.05, 0.10, 0.20 and 0.30 lbs·yd−3, respectively) and 0, 20, and 50% leaching were tested. The first experiment was conducted in winter (late November through December) and the second in spring (mid-March through April). The minimum-targeted, soluble-bulk-solution phosphate-P level of 3 mg.L−1 (ppm) was achieved for 41 d in the winter with a phosphate-P charge of 0.06 kg.m−3 (0.10 lbs·yd−3) and 20% leaching. Longevity for this treatment was 4 d less in the spring. At 0% leaching, the soluble-bulk-solution phosphate-P level was above the minimum target level of 3 mg.L−1 (ppm) for the entire 42-d period in both seasons. Increasing the leaching from 20 to 50% resulted in a loss of longevity by 4 d in the winter and 6 d in the spring. Index words: soilless media, bedding plants, floriculture, Petunia ×hybrida, plant nutrition. Species used in this study: petunia (Petunia ×hybrid var. multiflora Vilm.).

First Report of Rose rosette virus Associated with Rose Rosette Disease in Rosa hybrida in Minnesota

A Rosa hybrida plant was identified with rose rosette disease symptoms and was positive for Rose rosette virus (RRV) by reverse transcription PCR. It is important to monitor routinely roses for RRV symptoms and to test and rogue symptomatic plants. This is the first report of RRV infecting roses in Minnesota.