FarmersJoint.com

Full Version: Controling Damping-off and Downy Mildew Diseases of Cucumber with Plant Extracts
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
In an experiment conducted in southeast Nigeria, water extracts of ginger rhizomes, garlic bulbs, and neem leaves were tested to see if they can control damping-off and downy mildew diseases of cucumber. For each plant materials, 3 different concentrations of 4, 8 and 12% were tested. Tap water was used as control.

Pointe sett cucumber variety was used. Plant spacing was 50cm x 50cm on raised beds. NPK (15:15:15) fertilizer was applied at150 kg/ha using the ring method at 3 weeks after planting. Staking was done 4 weeks after planting. Harveting starts 46 days after planting at 6 days interval.

The plant extracts were prepared as follows:

Wash the plant materials separately with tap water, dry under shade, and separately crush them in a mortar with pestle. Add distilled water to each of the crushed plant material and stir for 5 minutes. Filter them separately through clean muslin clothes. Note: 4, 8 and 12% concentration simply mean 4, 8 and 12g dry plant materials in 100ml of water or 40, 80 and 120g dry plant material in 1L of water.

Cucumber seeds were treated as follows:
Soak seeds in the plant extracts for 1 hour. Drain and remove excess moisture with blotting papper, towel etc. Dry at room temperature for 2 hours before planting. The planting spots were also drenched with 20ml of the extracts.

Results: All the extracts at various concentrations significantly reduced damping off disease and increase germination rate and seedling survival.

From 4 weeks after planting, weekly sprays of the different plant extracts at all concentration tested significantly suppressed the incidence and severity of downy mildew disease. This resulted in improved growth and yield of cucumber plants when compared to control. One teaspoonful of an emulsifier (morning fresh), was added per 15L of extract. Spraying was stopped 1 week to harvest and only 4 harvests were made. But I believe better result would be gotten if spraying had continued because these plant extracts are not toxic like chemical fungicides. I just wondered why they stopped!

For control of both diseases, the most effective was ginger, followed by neem leaves and then garlic. The best concentration was 8%. Suprisingly, 4% concentrations were better than 12% concentrations against damping off. Some other research concluded that garlic extract was 50 -100% effective against downy mildew at volatile anti-microbial concenyration of 50 - 1000 ug/mL.

In terms of growth and yield, the effectiveness followed the same trend, with ginger being the best, followed by neem leaves and then garlic. Again, 8% concentration of the various extracts gave best result.

Source: https://www.ijsr.net/archive/v5i7/NOV163...Wfx1hQCtgv