Recipient Organization
UNIVERSITY OF VERMONT
(N/A)
BURLINGTON,VT 05405
Performing Department
PLANT & SOIL SCIENCES
Non Technical Summary
In order for crop producers to consider using dairy manure compost, a local logical resource, further research needs to be completed convincing them of its horticultural and economic effectiveness. The purpose of this study is to examine the impacts of integrating dairy manure compost banding into horticultural crop production with a special emphasis on vegetable production.
Animal Health Component
45%
Research Effort Categories
Basic
10%
Applied
45%
Developmental
45%
Goals / Objectives
The overall focus of this project will examine the impacts of integrating dairy manure compost banding into horticultural crop production with a special emphasis on vegetable production. The first round of experiments will take place under tightly controlled conditions in the UVM Greenhouse Complex. Several hypotheses will be tested related to plant growth and development with a special emphasis on root architecture. Examples of hypotheses to be tested include: HA: The root architecture (surface area, volume, length (by diameter class)) of tomato produced with a concentrated zone of compost (band) will be altered significantly from that of controls. HA: The total sweet corn root biomass in the concentrated band of compost, per volume of root substrate, will be significantly higher than either control in the greenhouse study. Once simulated compost banding experimental results are statistically analyzed and determined to be repeatable in the greenhouse, field
experiments to determine the agricultural validity of greenhouse findings will be conducted. These experiments will test biological hypotheses in the framework of functional farm practices. Two examples of hypotheses to be tested at the field-scale include: HA: Total marketable yield of sweet corn produced with the cultural practice of compost banding will not be significantly different than that of controls. HA: Total amount of irrigation supplied to maintain field plots of tomato at 65% Plant Available Water will be less for compost amended plots. Summarized Objectives: 1. Quantify the changes in root architecture of vegetables, and other species important to the horticulture industry, produced in containers with a localized concentration of compost that simulates field banding under controlled greenhouse conditions. 2. Evaluate optimum compost application strategies identified in greenhouse experiments for field produced tomatoes and sweet corn.
Project Methods
A randomized complete block design will be utilized to examine the effects of compost on the root architecture of tomatoes and sweet corn. All plants will be grown in 9 inch standard mum pots. A minimum of 15 individual plant (pot) replicates per treatment will be used in each experiment. Experiments will be replicated twice in time. Blocking will be utilized to control for temperature and light gradients that may occur in the greenhouse. Other horticulturally important plant species may also be examined if time permits. Supplemental lighting will be used for plants during winter experiments to compensate for short days. Dairy manure compost will be amended to the containers in two different ways. Either it will be added to sterilized sand at a field equivalent rate or it will be added to a localized cylinder at a higher concentration to simulate banding in the field. In recent multi-season experiments we have shown that a field rate of 89.7 Mg/ha (40 tons/acre) (wet
weight) can produce the same marketable yield in potatoes on a sandy soil as liquid nutrients applied at extension recommended rates for New England. Sand amended with the equivalent of 89.7 Mg/ha (40 tons/acre) will serve as the positive control (Fig. 1A.). Potatoes, sweet corn, and tomatoes have similar total seasonal nitrogen application recommendations (NEE, 2002). The banding treatment will have compost mixed with sterile sand and applied to the 5 X 15 cm cylinder only at a rate of 44.9 Mg/ha (20 tons/acre), 89.7 Mg/ha (40 tons/acre), or 179.4 Mg/ha (80 tons/acre) (Fig. 1B.). This is equivalent to a normal field application and incorporation at a rate of 11.2 Mg/ha (5 tons/acre), 22.4 Mg/ha (10 tons/acre), and 44.9 Mg/ha (20 tons/acre) (wet weight) respectively. Following 2 replications of this experiment in the greenhouse rates may be adjusted based on experimental results. Any adjustment of rates will be validated with two more greenhouse experiments replicated in time. These
lower rates are more typical of what many vegetable growers might actually consider cost effective. Finally the negative control for organic matter will consist of containers filled with sterile sand. Nutrients for these plants will be provided using synthetic soluble fertilizer applied at established rates for field tomato production or sweet corn. The two controls above were selected to be utilized for all greenhouse experiments. Control replicate number will match replicate treatment number in each experiment. In summary, a sample greenhouse experiment will consist of 3 randomized complete blocks, with 5 treatments (two controls and 3 simulated compost banding rates) with 15 pot replicates per treatment.