Transcript ppt2786 - دانشگاه آزاد اسلامی واحد کرج

Determining Weed Maps and
population characteristics of
Irrigated Wheat Fields for Sistan
and Baluchestan Province
H. Adim, M. Sarani, M. Minbashi
Moeini*
Accepted date: 16 Oct 20101Baluchestan Agricultural and Natural
Resources Research Center, Iranshahr,
Iran.
- Sistan Agricultural and Natural
Resources Research Center, Zabol,
Iran.3- Iranian Research Institute of
Plant Protection, Tehran, Iran.
*: Corresponding author's E-mail:
[email protected]
Abstract
neglecta Wallr.) and prostrate
knotweed (Polygonum aviculare L.)
were dominant broadleaf species in
• Key words: Weed mapping, geographic
irrigated wheat fields of Sistan and
information system (GIS), abundance index,
Balochistan
grass
(AI), frequency,province.
uniformity,Dominant
mean field density.
weed species were japanesse brome
(Bromus japonicus Thunb.ex murr),
winter wild oat (Avena ludoviciana
L./Dur.) and Canarygrass (Phalaris
minor Retz.). Hoary cress (Cardaria
draba (L.) Desv.), field bindweed
Influence of wild mustard (Sinapis
arvensis L.) different densities on
yield and yield component of winter
wheat (Triticum aestivum L.)
F. Bazrafshan1*, H. Moosavinia2, A.
Moezi3, A. Siadat4, R. Hamidi5
Agriculture, Shahid Chamran
University, Ahwaz.3- Assistant
professor, Faculty of Agriculture,
Shahid Chamran University, Ahwaz.4Professor, Ramin Agricultural and
Natural Resource, University.5Associate professor, Faculty of
Agriculture, Shiraz University.*:
Corresponding author's E-mail:
Abstract
ranged from 3.1 to 29.9% at 1 to 16
wild mustard per m2, respectively. At
16 plant per m2 wild mustard reduced
wheat spike per m2 by 16.2% and seed
number per spike per m2 by 19.6%,
when compared to weed free check.
Results also showed that increase in
wild mustard dry weight, due to
increase in mustard density, had
negative effect on wheat dry weight.
Wild mustard must be controlled either
Key words: Winter wheat, wild
mustard, competition, density.
germination and seedling growth of
Barnyardgrass (Echinochloa crus-galli
L.) and Rice (Oryza sativa L.), and its
relationship with their competition
under stress conditions.
A.
*
Esmaili ,
S.V. Eslami
Received date: 06 Mar 2009
Accepted date: 27 Jun 20101- M.Sc.
Student of Weed Science, University of
Birjand. Iran.
- Assistant Professor, University of
Birjand, Iran.*: Corresponding author's
E-mail:
Abstract
seeds kg soil in 2004 and 2005,
respectively. The weed seed bank
density in second sampling date (post
harvesting of barley) for CMFs were 33
and 30.5 seeds kg-1 soil, and for NCMFs
were 210 and 254 seeds kg-1 of soil in
2004 and 2005, respectively. Seed
bank density decreased over sampling
times (growing season) for CMFs in
2004 as compared with NCMFs. In
2005, the NCMFs variation trend of
the seed bank densities for managed
Key words: Rotation system, diversity
index.
Study of effectiveness of different
combinations of selective herbicides
for control of broadleaf weeds in
Sugar beet (Beta vulgaris L.) fields
H. Najafi*, M. Bazobandi, N. Jafarzadeh
Received date: 20 Oct 2010
Accepted date: 08 Dec 20101- Iranian
Research Institute of Plant Protection,
Tehran, Iran.
2- Khorasan Razavi Agricultural and
Natural Resources Research Center,
Iran.
3- Western Azarbayejan Agricultural
and Natural Resources Research
Center, Iran*:Corresponding author's
E-mail:
Abstract
frequency measurements in each
province indicated that
(phenmedipham + desmedipham +
ethofumesate) + triflusulfuron methyl
was the best composition.
triflusulfuron methyl + desmedipham
also was another composition that
produced a good result. These
treatments had no good effect on
bindweed. The least herbicidal effect
came from chloridazon + triflusulfuron
Key words: Sugarbeet, weed,
broadleaf herbicides, tankmixed.
– Primary growth of root and shoot of wild oat
(Avena fatua L.) and wheat (Triticum aestivum
L.) in competition for nitrogen
halepense), common lambsquarter
(Chenopodium album) and redroot
pigweed (Amaranthus retroflexus) for
5 days. Results showed that with
increasing concentration of wormwood
extracts, their effects on reducing seed
germination and seedling growth of the
above mentioned plants was more
severe. Comparison of extract effects
with polyethylene glycol, revealed that
reduction of Johnsongrass and
evaluated. The experiment results
showed that only corn grain number
was affected by the time of
application. Herbicide dose had
significant effect on grain weight. Both
application time and herbicide doses
significantly affected dry weight of
weeds. Later use of herbicide had no
effect on dry weight of weeds. Due to
good control of weeds by herbicide at
2.1 kg/ha, the grain yield increased
significantly when compared with
•
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Herbicides are one of the crucial options in weed management in most agricultural
production systems of world. The introduction of the new herbicide families has
had many benefits including very low application rates and low mammalian
toxicity. As these herbicides can also be absorbed through the foliage or roots and
have high mobility in plants, leading to broad-spectrum control of weeds and
having soil residual persistence that gives some control of emerging weeds after
application. That is why the use of these herbicide products was rapidly accepted
by agricultural producers for crop production. Although, this aspect of the new
herbicides is useful for control of emerging weed during the growth season, but
the herbicides residues can persist to the next season(s) and damage subsequent
crops. A wide range of interrelated factors impact the fate of herbicides in soil.
Understanding these factors and processes can make possible the best weed
control as well as reducing the potential for injury to non-target crops. Pertinent
environmental conditions consist of the chemical, physical and biological
characteristics of the soil to which the pesticides are used and climatic features
such as rainfall, wind, temperature and light regime. These factors particularly
moisture and temperature are two key factors that determine the extent of sorption
and degradation of herbicides in the soil matrix. Various mechanisms including
phtodegradation, volatilization, leaching, sorption and degradation are determinant
processes of herbicide behavior in the environment. The present paper is an
overview of the most important processes namely sorption and degradation of
herbicides in soil, the environmental factors and herbicides nature which affect the
behavior of these chemical in the soil.
Key words: Herbicides, soil persistances, adsorption, degradation.