Hybrid RB Macrophomina recipe for Macrophomina from soil and roots
From Bugwoodwiki
Ingredients
| Ingredients | For 1 Liter | For 0.5 Liter |
|---|---|---|
| agar | 39 g | 19.5 g |
| rifampicin | 100 mg | 50 mg |
| Metalaxyl (if needed) | 224 mg | 112 mg |
| Tergitol | 1 ml | 0.5 ml |
| chloroneb | 160 mg | 80 mg |
| Streptomycin sulfate | 250 mg | 125 mg |
Instructions
Metalaxyl: Apron XL is 32.3% a.i formulation. specific gravity=1.11 g/ml
Want 224 mg a.i.
Place stir bar in flask. Autoclave water and agar. Cool to about 60 C in water bath. When cooled, add fungicides and anti-biotics. Mix on stir plate.
For soil:
- Pre-sieve soil through a 80 mesh sieve to remove debris.
- Take 3, 5-gram soil samples of dried soils, weigh them and dry them in an oven (about 110 C) to determine percent soil moisture.
- To determine Macrophomina content:
- Take 5-gram subsamples of the soil.
- 3 cycles of: blend 30-seconds, let it sit 30-seconds. Blend in 250 ml of 0.5% NaOCl.
- Sieve through a 325 mesh sieve.
- Rinse contents of sieve for 2 min.
- Rinse contents of sieve into beaker with 25 ml distilled water.
- Mix with 90 ml RB agar above held at 50- 60 C.
- Swirl and plate into 6 petri plates while swirling.
- Incubate: 30 C for about 4 days.
For roots (useful for looking at number of points of infection):
- Rinse roots under running water.
- Blot dry on filter paper.
- Plate small sections in the 50 -60 C mixed media.
- Incubate 30 C for about 4 days.
Contributed by
Contributed by Alan Henn, the Mississippi State University
