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Seedling emergence of Amaranthus blitoides affected by soil depth

Alireza Taab,Mehrangiz Akbari and Saghi Anbari

JOINT WORKSHOP OF THE EWRS WORKING GROUPS:Weed management in arid and semi-arid climate

andWeed management systems in vegetables

4-8 September 2011Huesca, Spain

In The Name of God

Dept. of Agronomy and plant breeding, Faculty of Agriculture, Ilam University, 69315-516, Ilam, Iran Email: a.taab@mail.ilam.ac.ir

ILAM UNIVERSITYIRAN

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IntroductionProblem ?Weed in soybean, beans, vegetables etc.Crop yeild loss

BackgroundNumber of emerged seedling to deacrease with soil depth

Weed Management- Time of weed emergence- Number of weed emergence- Depth

Weed Emergence!When? And How Many?

Weed Control Options!

Crop

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Experiments

Pot experiment outdoor Soil: CLAY; Organic C: 1.16%

1 Species x 4 Blocks x 6 Soil Depths x100 SeedsDepths: 0, 2, 4, 6, 8, 10cmSeed collection: 5 January 2010Sowing date: 12 January 2010

Materials and Methodes:

Records: - soil temperature at 6 depths - numbers of emerged seedlings

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Results

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Mean Daily Soil Temperature

0

5

10

15

20

25

30

35

40

Time

Tem

per

atu

re C

Mean0d

Mean2d

Mean4d

Mean6d

Mean8d

Mean10d

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Amaranthus blitoides 2010

0

10

20

30

40

50

60

0 2 4 6 8 10Soil Depth (cm)

Se

ed

lin

g E

me

rge

nc

e (

%)

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ConclusionSeedling emergence:-When mean daily soil temperature increased above ca 10ºC with ca 5 to 25ºC fluctuation -The seedling emergence was stopped when the daily soil temperature raised above 20ºC, possibly due to induction of dormancy -Maximum seedling emergence was observed for seeds at soil surface and decreased with depth!-Seedling emerged over an extended period which make the species difficult to control-Weed control measures over an extended period with focus on larger seedling flushes

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Thanks For Your Attention