cumulative yield of three varieties of eggplant. World Crops Research Updates - Eggplant. Issue 5 - December 2015. Graph
World Crops Research Updates - Eggplant Issue 5 - December 2015 This document summarizes the findings of the Vineland’s research team on eggplant production for the 2015 growing season. Temperature and precipitation for 2015 Most of the country experienced warmer than usual weather in 2015. At the Vineland research farm, the temperature during the growing season was similar to the 30-year average although September and October were warmer than usual resulting in a longer growing season and higher yields for eggplant. Cumulative precipitation between May 1 and October 31 was 406 mm which was 85 mm lower than the long-term average of 491 mm. June and September were wetter than the long-term normal, July on the other hand was very dry (only 20.7 mm of precipitation) and August was average in terms of precipitation. Field production Six varieties of Chinese long eggplant were tested on the Vineland research farm. Transplants were grown on raised beds with black plastic mulch in double rows spaced 180 cm centre to centre and plants were spaced 45 cm apart in the row. Farmers’ Long, Asia Beauty and Long Purple hybrids were amongst the best varieties meeting retail specifications for Chinese long eggplant. Despite good yield potential,
Slim Purple and Violet King did not meet retail specifications. The graph below summarizes the yield differences among Chinese long eggplant varieties tested at the research farm.
Graph 1: Variety trial of Chinese long eggplant.
Orient Express hybrid has a very high yield potential and is sometimes referred to as Japanese eggplant. Its fruit is slender with an oblong shape. Its glossy skin has a purpleblack colour and is thin enough to not require peeling prior to use. Currently, its availability is limited to specialty ethnic stores and farm markets, although retail representatives have expressed interest in this variety. The graph on the next page shows the cumulative yield of three varieties of eggplant.
Fumigation Verticilium and Fusarium wilt are soilborne diseases of eggplant; at present, they can only be controlled by fumigation. Graph 3 summarizes the comparison between fumigated and non-fumigated plots on land where Fusarium was present at infectious levels in the soil.
Graph 2: Variety trial cumulative yield for Chinese long eggplant.
Orient Express F1 not only has a very high yield potential (over 50 mt/ha) but was also the earliest eggplant harvested. This variety, if embraced by the marketplace, has the potential of delivering outstanding yield and quality.
Graph 3: Eggplant fumigation trial.
Farmers’ Long F1 and Long Purple F1 were less affected by Fusarium wilt (42 percent and 46 percent yield reduction, respectively) than Chu-Chu F1 and Asia Beauty F1 where yield reduction was much more severe (72 percent and 79 percent, respectively). Grafting In many parts of the world, grafting onto tolerant rootstocks is an effective strategy to overcome soilborne diseases. Chinese long eggplant varieties were grafted onto Maxifort rootstock and tested at the research farm. Grafting improved overall plant health compared to non-grafted plants over the entire growing season but also delayed flowering and fruit set by about two to three weeks resulting in a delayed harvest. Grafted plants were more brittle and grew taller than Picture 1: Orient Express F1 (August 10, 2015).
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non-grafted plants. Staking was also necessary to support the plants. In 2016, other rootstock varieties will be tested to identify the most suitable combination of rootstock and variety for best performance.
poor plant growth and low yields. Graph 5 shows the yield response to various rates of nitrogen on non-grafted and grafted eggplant grown at the research farm.
The graph below shows the effect of staking on the yield of Long Purple grafted plants.
Graph 5: Eggplant nitrogen response curve.
Graph 4: Staking trial of Chinese long eggplant.
Soil fertility Well-drained, sandy loam soils are ideal for eggplant production. Poorly drained soils usually result in reduced functional root area,
Picture 2: Eggplant staking trial.
Grafted eggplants achieved the highest yields at 100 to 110 kg/ha of nitrogen fertilization and non-grafted plants at 70 to 80 kg/ha. One third of the fertilizer was applied before beds were built while the remaining nitrogen was applied through drip irrigation. More data is needed to optimize nitrogen fertility recommendations.
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Vineland Research and Innovation Centre 4890 Victoria Avenue North, Box 4000 Vineland Station, ON L0R 2E0 tel: 905.562.0320
@vinelandrsrch
VinelandResearch
vinelandresearch.com About Vineland’s Feeding Diversity: Bringing World Crops to Market As part of a collaborative group of partners determined to build a local ethno-cultural vegetable marketplace, Vineland is leading research on new crop varieties (okra, Asian and Indian eggplant), production technologies, postharvest innovations, consumer insights and market development. Vineland’s production team is trialing new varieties to assess agronomic performance and disease resistance, while postharvest scientists are working to optimize storage conditions to preserve the quality of ethno-cultural vegetables through the distribution chain and at retail.
Picture 3: Harvested eggplant.
Takeaway messages • Fumigation is necessary in fields with a history of soilborne diseases such as Fusarium and Verticilium wilt. • Orient Express F1 was the highest yielding eggplant variety. Although retailers expressed interest, the market is yet to be developed for this type of eggplant. • Asia Beauty, Farmers’ Long and Long Purple hybrids showed the best yield potential at Vineland and also meet retail specifications for Chinese long eggplant. • Grafting eggplant onto Maxifort rootstock delays flowering and fruit set and is undesirable for field production. • Staking is necessary for grafted plants as they grow taller. • Nitrogen rates of 80 to 110 kg/ha is necessary to achieve optimal yield.
Dr. Viliam Zvalo, Research Scientist, Vegetable Production joined Vineland in 2014 to investigate field and greenhouse production of world crops for Ontario growers. If the information contained in these research updates is of interest to you or if you have any questions, please contact Viliam at: 905-562-0320 x808 or
[email protected]
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