Wheat seeds were coated with a biopolymer gel containing cells of Serratia entomophila. The coated seeds were either placed in polystyrene bags for stability testing or sown into large pots as shown below.
1a. Seedling protection by seed coating
Few seedlings emerging from untreated seed survived in the pots with grass grub larvae. A high emergence of vigorous seedlings was obtained with seed treatment.
| No. of seedlings/pot for | ||
| Treatment | Rye grass1 | Clover1 |
| Untreated seed | 5.67 | 2.00 |
| Coated seed | 14.33 | 15.67 |
1Mean of 3 replications, number of larvae/pot =3
Wheat seedlings treated with Serratia entomophila for grass grub control
Untreated seed
Treated seed
Bacteria survived with little loss in viability for two months when the coated seeds were held under refrigeration. There was little loss in viability after one month at 20oC.
Survival of bacteria on coated seed at 4oC
| Total viable cell count/g of seed | |||
| Bacteria/Cultivar | Initial | 1 Month | 2 Months |
| Serratia entomophila / Wheat | 8.81 x 107 | 4.8 x 107 | 5.6 x 107 |
| Serratia entomophila / Wheat | 6.14 x 107 | 4.5 x 107 | 4.7 x 107 |
Shelf of S. entomophila on coated seed at 20oC
| Total viable cell count/ g of seed | |||
| Bacteria/Cultivar | Initial | 1 Month | |
| Serratia entomophila / Wheat | 6.35 x 109 | 41.33 x 108 | |
