- Vegetables: tomatoes
- Crop Production: conservation tillage
- Education and Training: on-farm/ranch research
- Pest Management: biological control, cultural control, mulches - living, mulching - plastic, prevention
- Soil Management: green manures, organic matter, nutrient mineralization, soil chemistry, soil microbiology, soil physics, soil quality/health
Recent research suggests good root colonization of arbusucular mycorrhizae (AM) is very important for “priming” natural defensive reactions in plants to fungal and bacterial diseases. I suspect colonization of AM fungi in most vegetable farmers fields is lower than ideal, because tillage disrupts AM’s life cycle and has been shown to reduce it’s diversity and number of propogules in a field. I am interested to see if interplanting tomato plants into a perennial and well established living mulch will increase infection rates over controls and help the plants better resist fungal disease, possibly increasing marketable yields. Nutritional status, yield, disease incidence and AM fungi colonization of replicated plots given three treatments will be recorded, then statistically analyzed to determine possible beneficial or negative effects of interplanting tomatoes into a perrenial living mulch. Outreach will be through a twilight meeting held at the University of Rhode Island organized by cooperative extension. At this meeting the trial will be discussed with farmers and educators from around the state.
Project objectives from proposal:
Early and high rates of arbuscular mycorrhizal infection in tomato roots may increase disease resistance and marketable yield. Perennial living mulches with an ever-living root system may help to attain good mycorrhizal infection in the interplanted tomato crop. This is because mycorrhizal fungi are not host specific, and infection is shared between local plants (Hodge, 2000) (Marschner, 2011). White clover var. White Dutch (Trifolium repens) will be used as a living mulch because of its low growing nature, shade tolerance, traffic tolerance, relative ease of establishment, and associations with arbuscular mycorrhizae (AM).
This trial will consist of three different treatments each replicated four times. Tomato cultivar ‘Marbonne’ will be seeded into plug trays in April. Seedlings will be transplanted into all field plots in early June at an in row spacing of 2 feet, pruned to three stems and maintained with a basket weave trellis. All plots will be harvested three times a week or as needed. Fruit will be weighed and sorted into two grades: 1.) Marketable fruit: those fruits with little to no physiological disorders or 2.) Cull Fruit: those with moderate to severe physiological disorders or defects. Two treatments called “Living mulch” (LM) and “Incorporated living mulch” (ILM) will be replicated four times down a 5×240 foot row of White Clover (Trifolium repens), established in May of 2015. A third treatment “Bare ground cultivated” (BGC) will serve as a control and will be replicated four times down a parallel row.
In the (LM) treatment, the white clover living mulch will be strip-tilled (approx. 16 inch width) in May 2016 with a rototiller and a one-foot wide piece of black plastic mulch material will be laid in the crop row. The clover outside this strip will remain unsuppressed all season except for mowing as needed with a standard mulching lawn mower. Tomato plants will be planted into the plastic mulch in June.
In the (ILM) treatment, white clover will be fully incorporated across the plots using a rototiller in May 2016. Mulch will be laid in the row as described above and the ground on either side of the row will be maintained by shallow cultivation, kept free of any vegetation.
In the (BGC) treatment, brassica and swiss chard greens were harvested in late September of 2015. The ground was rototilled and will be left bare over the winter with no cover crop. In May of 2016, it will be rototilled again and plastic mulch will be laid in the crop row as described above. The ground on either side of the row will be maintained by shallow cultivation, kept free of any vegetation.
On two dates, approximately July 1st and September 1st. one composite sample of young roots from the tomato plants, gathered at a replicated location of 12” to the east of the main stem of 3 random and replicated plants will be mixed from every plot and will be sent to Earthfort lab Corvallis, OR to assess % colonization of the tomato roots by Arbuscular Mycorrhizae.
Tissue samples will be taken on five dates through out the trial from every plot and will be sent to the University of Connecticut for nutrient analysis.
On five dates throughout the growing season disease incidence in all plots will be rated using the Horsfall- Barratt scale.
Differences in this information, including yield, nutritional status and disease incidence in the different plots and treatments will be statistically analyzed in order to determine if any treatment had benefits in increasing marketable yield.
April 10th Planting Tomato Seeds ‘Marbonne’ in Plug Trays April 10th-June 1st Growing tomato seedling plants
June 1st Planting of tomato ‘Marbonne’ seedlings in all plots
June 1st-Frost or plant death. Maintaining the tomato plants in all plots including pruning, staking and basket weaving the plants. Fruit will also be harvested every 3 days or as needed once it begins to ripen. All of this data will be recorded immediately.
Samples for tissue analysis will be taken on the following dates and sent to the University of Connecticut for nutrient analysis. June 21st, July 15th, August 1st August 21st and September 15th.
Samples to assess arbusuclar mycorrhizal colonization will be sent to Earthfort Labs on the following days. July 1st and September 1st.
Disease incidence in all plots will be rated using the Horfall-Barratt scale on the following dates July 1st, August 1st, August 21st, September 7th and October 1st.
The twilight Outreach meeting will be held some day in September where the trial will be presented to other farmers and educators from the state.
Outreach will be through a meeting with other farmers in the state. This will be a Twilight Outreach meeting organized by URI cooperative extension. This will be held at the agronomy farm on campus. Among other topics, the results of this research project (to date) will be presented to other farmers from the state. The results will be printed for distribution at the meeting. The estimated attendance for the meeting (based on previous meetings) will be 25 to 30 farmers. The exact date is undetermined but will occur in September,2016.