Harry A. J. Hoitink, Professor, Department of Plant Pathology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio; Carol A. Musselman and Terry L. Moore, Research Assistants, Department of Plant Pathology, Ohio Agricultural Research and Development Center, The Ohio State University; Leona E. Horst, Research Assistant; Charles R. Krause, Adjunct Associate Professor, U.S. Department of Agriculture, Agricultural Research Service, Application Technology Research Unit, Wooster, Ohio; Randy A. Zondag, Ohio State University Extension, Chair and Extension Agent, Lake County, Painesville, Ohio; and Hannah Mathers, Assistant Professor, The Ohio State University, Department of Horticulture and Crop Science, Columbus, Ohio.
Effects of Composted Cow Manure and T382 on Growth of Perennials and Ground Cover Plants
Liners of Ajuga, Sedum, and Viola were transplanted on June 14, 2002, into 1-gallon containers.
Container mix treatments were:
The mean number of flower stalks per plant and canopy size were determined at the completion of the growing season for Ajuga 'Burgundy Glow.' A mean salability rating was determined for Sedum 'Autumn Joy' and Viola 'Purple Showers.' A randomized complete block design was used with four blocks of 12 plants per treatment.
Amendment of the grower mix with composted dairy manure significantly increased the number of flower stalks and canopy size on Ajuga 'Burgundy Joy' (Table3). Salability of Sedum 'Autumn Joy' also was drastically improved by amendment with the compost. Viola 'Purple Showers' was stunted in growth during the first six weeks after potting in the mix amended with composted cow manure.
| Table 3. Effects of a Composted Cow Manure-Amended Potting Mix and of Trichoderma hamatum 382 (T382) on Growth and Flowering of Ajuga 'Burgundy Glow,' Sedum 'Autumn Joy,' and Viola 'Purple Showers.' | ||||
| Potting Mix1 | Ajuga 'Burgundy Glow'2 | Sedum 'Autumn Joy'3 Salability Rating |
Viola 'Purple Showers'3 Salability Rating |
|
| Canopy Size (L) | # Flower Stalks per plant | |||
| Grower control mix | 0.6 | 2.4 | 3.7 | 3.7 |
| SD compost | 1.5 | 3.0 | 4.2 | 3.9 |
| SD compost+ T382 | 1.4 | 2.8 | 4.2 | 3.2 |
| LSD 0.05 | 0.5 | 0.2 | 0.4 | 0.4 |
|
1 Grower mix consisting of aged pine bark and composted rice hulls (8:3; vol./vol.) was amended with sawdust-bedded composted cow manure (5%; vol./vol.) (SD compost) or the same and inoculated with 100 g granular inoculum of T382 per cubic yard of mix. 2 Planted on June 14, 2002. Mean number of flower stalks per plant (n = 48) determined on August 7, 2002, and canopy size determined on September 3, 2002. 3 Planted on June 14, 2002. Mean salability (n = 48) determined on August 7, 2002, based on a scale in which:5 = full height, large flower; 4 = full height, small flower; 3 = slightly stunted, chlorotic; 2 = severe stunting and chlorosis with stem lesion caused by Phytophthora dieback; 1 = dead plant. |
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Symptoms suggested that the ammonium concentration in the mix at planting was too high and caused phytotoxicity. Towards the end of the 2002 growing season, Viola plants had recovered, and the mean salability did not differ from that in the mix not amended with the composted manure.
The 2002 summer was extremely dry where this demonstration test was performed. As a result, disease pressure was low, and foliar diseases did not develop. Root rots also were not observed on plants in any of the mixes even though fungicide drenches were not applied. Within days after potting, some Sedum plants randomly distributed across the treatments developed Phytophthora stem blight. Conditions were too dry for spread of the disease, however.
T382, as expected, had no major effect on Ajuga or Sedum because of low disease pressures. On Viola where phytotoxicity was observed, salability was affected negatively. The inducing effect of T382 may have interacted with the toxicity that apparently was caused by excessive ammonium concentrations early after potting in the composted cow manure-amended mix.
In conclusion, amendment of the grower mix with composted cow manure improved growth on two species and caused a temporary setback on Viola, a plant known to require low fertility conditions. Disease pressures were too low to allow observations on T382.