Assessment of allelopathic potential in Artemisia annua on

Assessment of allelopathic potential in Artemisia annua on maize, wheat and their some associated weed Artemisia annua species By Hassanein, E. E; Abd El-Hamid, M. M. and M. S. , Mekky Weed Res. , Lab. , Field Crop Res. Inst. , ARC, Giza Egypt.

Objectives : To study the allelopathic effect of wormwood extracts on germination, growth of maize and wheat as well as associated weed species.

Materials and Methods A - Laboratory experiments: Two experiments were conducted as follow: -. Experiment I (preliminary experiment): Included 14 concentrations (0, 3, 6, 9, 12, 15, 30, 45, 60, 75, 90, 120, 135 and 140 mg dry weight ml-1 c water), replicated twice to determine sensitivity range of maize to the studied extracts. Experiment II: Included 8 concentrations (0, 3, 6, 9, 12, 15, 18 and 21 mg dry weight /ml) replicated three times to determine the required concentration to cause 50% inhibition of seed germination (I 50).

B - Wire house experiments: Three pot experiments were conducted to study the effect of wormwood extracts on maize, wheat and associated weed species in pots. Maize experiments: Two pot experiments were conducted to study the effect of wormwood extracts on maize and some weed species in pots as follow:

The 1 St experiment included Seven treatments on pots in three replicates as follow: 1 -Wormwood extract at 3 g/pot applied at 3 days after sowing (DAS). 2 -Wormwood extract at 1. 5 g /pot applied at 3 DAS. 3 -Wormwood extract at 0. 75 g/pot applied at 3 DAS. 4 -Wormwood extract at 3 g/pot applied at 21 DAS. 5 -Wormwood extract at 1. 5 g/pot applied at 21 DAS. 6 -Wormwood extract at 0. 75 g/pot applied at 21 DAS 7 - Check (control).

The 2 nd experiment on maize included seven treatments in pots in replicated three times as follow: 1 - Wormwood extract at 1. 5 g/pot applied at 3 DAS. 2 - Wormwood extract at 0. 75 g/pot applied at 3 DAS. 3 - Wormwood extract at 0. 38 g/pot applied at 3 DAS. 4 - Wormwood extract at 1. 5 g/pot applied at 21 DAS. 5 - Wormwood extract at 0. 75 g/pot applied at 21 DAS. 6 - Wormwood extract at 0. 38 g/pot applied at 21 DAS. 7 - Check (control).

Wheat experiment: Included five treatments in pots as follow: 1 -Wormwood extract by natural white vinegar 2. 5% acetic acid at 3 g/pot applied at 2 -5 leaves of weed. 2 -Wormwood extract by water at 3 g/pot applied at 2 -5 leaves of weed. 3 -Wormwood extract by water at 3 g plus 3. 3 ml acetic 2. 5%/pot applied at 2 -4 leaves of weed. 4 -Natural white vinegar 2. 5% acetic acid at 50 ml/pot applied at 2 -4 leaves of weed check (control). 5 - Check (control).

Results and Discussion A- Laboratory experiments: • The required concentration of extract for causing 50% inhibition of germination of maize was 4 mg/ml.

B - Wire house experiments 1 – Maize crop

Results of the 1 st pot experiment of maize 1 - The post emergence application of wormwood extract at the rate of 3 g/pot achieved the highest reduction in number and fresh weight of weeds (100%), however, this dose reduced caused slight phytotoxicity to maize plants. 2 - Post emergence application of wormwood extract at the rate of 0. 75 g/pot achieved the best reduction of total weeds without any inhibitory effect on maize plant.

Table (1): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on number of weed species under wire house condition (first exp. 4/3/2008). Number of broad leaved weeds pl. /pot Number of canary grass (pl/pot) Number of total weeds (pl/pot) barri Other weeds Total broad leaf weeds 2. 3 2. 0 1. 5 10. 0 9. 8 19. 8 2. 3 2. 0 2. 3 0. 5 7. 0 10. 8 17. 8 0. 75 g/pot PRE 2. 5 0. 0 3. 3 0. 3 6. 0 45 10. 5 3 g/pot POST 0. 0 0. 0 1. 5 g/pot POST 0. 5 0. 0 0. 5 5. 5 6. 0 0. 75 g/pot POST 0. 0 2. 3 1. 5 0. 5 4. 3 3. 5 7. 8 Check (control) 6. 8 7. 0 4. 8 2. 0 20. 5 6. 0 26. 5 LSD 1. 4 2. 2 2. 1 1. 5 4. 0 6. 11 8. 3 Concentration Gossefoot Dentated dock Khardal 3 g/pot PRE 4. 3 1. 5 g/pot PRE

Table (2): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on number and fresh weight of maize and weed species under wire house condition (first exp. 4/3/2008). Fresh weight of broad leaved weeds (g/pot) Fresh weight of total weeds (g/pot) Gossefoot Dentated dock Khardal barri Other weeds Total broad leaf weeds Fresh weight of canary grass (g/pot) 3 g/pot PRE 0. 4 0. 6 0. 2 0. 1 1. 3 1. 1 2. 4 1. 5 g/pot PRE 0. 5 0. 4 0. 1 1. 4 1. 1 2. 5 0. 75 g/pot PRE 1. 3 0. 0 0. 8 0. 1 2. 2 0. 5 2. 7 3 g/pot POST 0. 0 0. 0 1. 5 g/pot POST 0. 1 0. 0 0. 1 0. 2 0. 3 0. 75 g/pot POST 0. 0 0. 2 0. 1 0. 4 0. 2 0. 6 Check (control) 2. 1 2. 9 1. 1 0. 3 6. 4 0. 6 7. 0 0. 6 0. 5 0. 6 0. 1 0. 9 N. S 1. 7 Concentration LSD

Table (3): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on maize under wire house condition (first exp. 4/3/2008). Maize Concentration Number (pl/pots) Inhibition % Wight (g/pl) Inhibition % 3 g/pot PRE 5. 0 0 8. 7 0. 0 1. 5 g/pot PRE 4. 8 5 8. 1 6. 8 0. 75 g/pot PRE 4. 5 10 8. 8 0. 0 3 g/pot POST 4. 0 20 4. 8 44. 8 1. 5 g/pot POST 4. 8 5 7. 7 11. 5 0. 75 g/pot POST 5. 0 0 9. 7 0. 0 Check (control) 5. 0 0 8. 7 0. 0 LSD 0. 6 1. 4

Artemisia plant

Artemisi a plant 3 g/pot pre-emergence post-emergence

Artemis ia plant 1. 5 g/pot pre-emergence post-emergence

Results of the second pot experiment of maize 1 - All studied concentrations of wormwood extract when applied at 3 days after sowing or at 1. 5 and 0. 75 g/pot when applied at 21 after sowing significantly reduced number and fresh weight of redroot pigweed, purslane and deccan grass. 2 - Redroot pigweed and purslane as broad leaved weeds were more susceptible than deccan grass for wormwood extract. 3 - Number and fresh weight of maize plant was not significantly affected by all wormwood extract concentration under study.

Table (4): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on number under wire house condition (second exp. 15/4/2008). Concentration Number of redroot pigweed (pl/pot) Number of purslane (pl/pot) Number of total broad leaf weeds (pl/pot) Number of deccan grass (pl/pot) Number of total weeds (pl/pot) 1. 5 g/pot PRE 3. 0 0. 7 3. 7 1. 0 4. 7 0. 75 g/pot PRE 6. 7 0. 7 7. 4 3. 0 10. 4 0. 38 g/pot PRE 7. 0 1. 7 8. 7 5. 3 14. 0 1. 5 g/pot POST 2. 7 4. 0 6. 7 6. 0 12. 7 0. 75 g/pot POST 7. 3 9. 7 17. 0 7. 7 24. 7 0. 38 g/pot POST 14. 7 9. 7 24. 4 16. 7 41. 1 Check (control) 14. 0 13. 3 27. 3 13. 0 40. 3 LSD 6. 4 3. 5 8. 4 5. 3 11. 2

Table (5): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on fresh weight of weed species under wire house condition (second exp. 15/4/2008). Weight of purslane (g/pot) Weight of total broad leaf weeds (g/pot) Weight of deccan grass (g/pot) Weight of total weeds (g/pot) 17. 2 18. 4 2. 6 21. 0 0. 75 g/pot PRE 37. 0 0. 8 37. 8 1. 2 39. 0 0. 38 g/pot PRE 40. 6 2. 3 42. 9 14. 3 57. 2 1. 5 g/pot POST 9. 2 4. 9 14. 1 14. 5 28. 6 0. 75 g/pot POST 36. 7 10. 3 47. 0 25. 0 72. 0 0. 38 g/pot POST 45. 2 18. 3 63. 5 12. 0 75. 5 Check (control) 109. 4 25. 3 134. 7 169. 4 LSD 39. 3 9. 7 38. 5 11. 5 43. 5 Concentration Weight of redroot pigweed (g/pot) 1. 5 g/pot PRE

Table (6): Effect of aqueous acetic 5% extract of wormwood when applied either pre or post emergence on number and fresh weight of maize under wire house condition (second exp. 15/4/2008). Concentration Number of maize plant / pot Fresh weight of maize (g/pot) 1. 5 g/pot PRE 4. 8 168. 7 0. 75 g/pot PRE 5. 0 158. 3 0. 38 g/pot PRE 5. 0 159. 0 1. 5 g/pot POST 4. 6 167. 3 0. 75 g/pot POST 5. 0 159. 0 0. 38 g/pot POST 5. 0 161. 7 Check (control) 5. 0 108. 0 L. S. D N. S 24. 2

0. 75 g/pot pre-emergence post-emergence

B - Wire house experiments 2 – Wheat crop

Results of the third experiment of wheat 1 - Application of wormwood extract by natural white vinegar at 3 g/pot from achieved the best reduction in number and fresh weight of canary grass when applied at 2 -4 leaves. 2 - Broad leaved weeds were more sensitive than grassy weeds.

3 - Number and fresh weight of most of broad leaved weeds as well as total annual weeds were significantly reduced by aqueous and natural white vinegar of wormwood extract at 3 g/pot when applied at 2 -4 leaves. 4 -Wheat plants did not affected by different wormwood extracts and natural white vinegar 2. 5% acetic acid (control) or water check.

Table (5) Effect of aqueous of wormwood and wormwood extracts by natural white vinegar 2. 5% acetic acid extracts of wormwood as post emergence on number of weed species. Number of grassy weeds (plants/pot) Number of broad leaved weeds (plants/pot) Concentration Primpernel Total broad leaved Wild oat Canary grass Total grassy weeds Number of total weeds Sowthistle Gossefoot Khardal barri Wormwood by natural white vinegar (3 g/pot) 1. 7 2. 0 0. 0 1. 0 4. 7 5. 3 0. 0 5. 3 10. 0 Aqueous wormwood extract (3 g/pot) 0. 7 1. 0 0. 0 1. 7 2. 3 6. 0 8. 3 10. 0 Aqueous wormwood extract (3 g/pot) + 3. 3 ml acetic/pots 0. 0 0. 0 4. 0 2. 0 6. 0 Natural white vinegar 4. 0 2. 7 7. 7 11. 7 26. 0 5. 3 4. 0 9. 3 35. 3 Check (control) 4. 7 3. 0 13. 3 14. 3 35. 3 5. 0 3. 0 8. 0 43. 3 LSD 1. 8 N. S. 3. 6 2. 3 2. 9 N. S 2. 3 2. 5 3. 3

Table (5) Effect of aqueous of wormwood and wormwood extracts by natural white vinegar 2. 5% acetic acid extracts of wormwood as post emergence on fresh weight of weed species. Concentration Fresh weight of grassy weeds (g/pot) Primpernel Total broad leaved Wild oat Canary grass Total grassy Fresh weight of total weeds Fresh weight of broad leaved weeds (g/pots) Sowthistle Gossefoot Khardal barri Wormwood by natural white vinegar (3 g/pot) 1. 2 3. 7 0. 0 1. 3 6. 2 50. 6 0. 0 50. 6 56. 8 Aqueous wormwood extract (3 g/pot) 2. 4 5. 8 0. 0 8. 2 28. 1 32. 9 61. 0 69. 2 Aqueous wormwood extract (3 g/pot) + 3. 3 ml acetic/pots 4. 7 3. 8 7. 6 7. 1 23. 2 61. 8 8. 5 70. 3 93. 5 natural white vinegar 2. 5% acetic acid 4. 7 3. 8 7. 6 7. 1 23. 2 61. 8 8. 5 70. 3 93. 5 check (control) 5. 1 6. 2 17. 4 15. 7 44. 4 60. 6 2. 7 63. 3 107. 7 LSD 2. 6 6. 8 4. 7 3. 8 8. 4 N. S 30. 9

Control Natural white vinegar

Extract of wormwood in solved natural white vinegar Aqueous wormwood mixed 3. 3 ml natural white vinegar