1. Presentation

Characterization of the technique

Description of the technique:

François Dumoulin	Chambre d'Agriculture de l'Oise	francois.dumoulin(at)agri60.fr	Fresnoy le Luat (60)
Laurence Guichard	INRA	Laurence.guichard(at)grignon.inra.fr	Grignon (78)
Jérôme Pernel	Agro-Transfert Ressources et Territoires	j.pernel(at)agro-transfert-rt.org	Estrées-Mons (80)
Julien Halska	INRA	julien.halska(at)grignon.inra.fr	Epoisses (21)

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This consists of delaying sowing by two to three weeks after the usual period in the considered geographical area.

Example of implementation: In the Paris basin, sowing of wheat soft from October 10 - 15 at the earliest (or even early November in organic farming) instead of September 25.

Details on the technique:

Warning, for weed management, it is necessary to take into account the problematic flora of the plot. Indeed, delaying sowing is effective to disadvantage certain species, but can favor others (for example, cleavers).

Crops concerned :

Crops sown in autumn / winter

Winter Oats, Durum wheat, winter Soft wheat, Einkorn, Small spelt, Spelt, winter Barley, winter Rye, winter Triticale (notably against bunt, except which are not sensitive).

TO CHECK: Garlic, winter Faba bean, winter Flax fiber, Flax seed winter, winter sweet Lupin, winter Mustard, Italian ryegrass

Crops sown in spring

Spring oats, Soft wheat spring, Sorghum silage, Sorghum grain, Sunflower, Triticale spring, spring peas.

Summer cauliflower: Delay sowing to July to avoid the 2nd flight of cabbage fly.

Sweet corn, grain corn, silage corn: Preferable regarding the European corn borer in areas with multiple generations as it limits the establishment of the second generation.

Beet: avoids early emergence of weeds in beets that emerge slowly.

Pea: To check, sowing date may be imposed by contract with an industrial buyer.

Potato: Probably little effect if a pre-emergence herbicide is used.

TO CHECK: Artichoke, Camelina, Hemp, Spinach, Fenugreek, Faba bean spring, Green bean, Lentil, spring flax fiber, spring flax seed, Lupin white spring, blue lupin spring, Melon, Mustard spring, summer Turnip, Poppy (corn poppy), Leek, Chickpea, Rice, Buckwheat, Soybean, Tobacco, industrial Tomato.

Crops sown in summer

Autumn and winter Cauliflower: Delay sowing to July to avoid the 2nd flight of cabbage fly.

Crops to be sown between spring and autumn

To check: Carrot, Vetch, Lettuce, Alfalfa, white or yellow Melilot, Millet, Sorghum, Onion, Phacelia, Meadow, Perennial ryegrass, Sainfoin, White clover, Clover Alexandrian, Micheli clover, Persian clover, Crimson clover, Purple clover, common Vetch

Forage cabbage: earlier sowing more smothering?

Implementation period On established crop

This technique can contribute to the diversification of sowing periods in the rotation.

Spatial scale of implementation Plot

Application of the technique to...

All crops: Not generalizable

This technique is easily applicable to autumn-sown crops. For spring crops, the risk of water stress may limit possibilities.

All soil types: Sometimes difficult to generalize

Delaying sowing on clay soils is more delicate because drying is slower in case of early and persistent rains. On sandy soils with low water reserve, early sowing allows better use of autumn and winter moisture.

All climatic contexts: Sometimes difficult to generalize

Delicate technique in areas with early and heavy autumn rainfall, which can prevent sowing under good conditions. In some regions, usual sowing dates are already late and occur after the peak emergence of weeds.

Regulation

NEGATIVE influence

For some contracted crops (vegetables for example), the sowing date is imposed on the farmer.

Production contracts

2. Services provided by the technique

3. Effects on the sustainability of the cropping system

"Environmental" criteria

Effect on air quality: Variable

Phytosanitary emissions: DECREASE

GHG emissions: VARIABLE

Effect on water quality: Decreasing

N.P.: INCREASE

Pesticides: DECREASE

Effect on fossil resource consumption: Variable

Fossil energy consumption: VARIABLE

Other: No effect (neutral)

Water: Use of herbicides (usually autumn herbicides suppressed), insecticides and fungicides can be reduced. On cereal straw crops (Agro-transfert RT), the herbicide IFT can drop from 1.58 to 0.58. However, the risk of nitrogen leaching is increased (stimulation of mineralization if false sowing), as well as the risk of phosphorus runoff.

Air: Use of herbicides (usually autumn herbicides suppressed), insecticides and fungicides can be reduced. On cereal straw crops (Agro-transfert RT), herbicide IFT can drop from 1.58 to 0.58. GHG emissions increase in case of false sowing, but can be largely offset by reduced nitrogen fertilization.

Fossil energy: Increase in case of false sowing, and if ploughing is necessary due to degraded weather conditions. Fewer sprayer passes.

Erosion risk: Increase. Soil is left bare for a longer period in autumn.

"Agronomic" criteria

Productivity: Variable

No effect or decrease. The cycle duration is reduced, which lowers yield potential for very late sowings (delay due to a rainy episode for example). For wheat, this effect is very moderate for sowings done at the end of October, or even nil if staying within the optimal window. Thus, a compromise must be found between reducing pests pressure and potential yield loss. This will also depend on pedo-climatic context and the year.

Soil fertility: No effect (neutral)

Water stress: Increasing

Especially on sandy soils.

Functional biodiversity: Variable

In case of association with one or more false sowings (which is recommended against weeds), soil fauna is disturbed.

Other agronomic criteria: Increasing

Control of certain pests: Increasing

But some pests like the cereal leaf miner can be favored, especially after a beet or onion crop. Risk can be reduced by increasing sowing density and firming the seedbed.

Control of establishment quality: Decreasing

Establishment conditions can sometimes be poor, especially on clay soil.

Risk of surface crusting: Increasing

Soil is left bare for a longer period in autumn.

"Economic" criteria

Operational costs: Decreasing

Possibility to reduce nitrogen fertilization and treatments. Increase in seed cost due to higher density. According to Agro-transfert RT, total weed control cost drops from 47 to 40 euros per hectare.

Mechanization costs: Decreasing

Fewer sprayer passes.

Margin: No effect (neutral)

The cost reduction generally compensates for possible yield losses linked to late sowing. Margin can even improve, but may also decrease in some cases.

Other economic criteria: Variable

Fuel consumption: Variable.

Slight increase due to sowing in wetter conditions, but fewer sprayer passes.

"Social" criteria

Working time: No effect (neutral)

Slight increase in case of false sowings.

Overall workload: Decreasing. Possible slight increase in sowing time if conditions deteriorate, but decrease in spraying time in autumn. Possible decrease in weeding time for very late sowings (according to an Agro-transfert RT trial, from 0.24 to 0.12 hours) or little effect for slightly delayed sowings (due to need for mechanical weeding in spring).

Peak period: Increasing

Risk of conflicts between operations: intervention windows shorten, which strongly impacts autumn operation scheduling.

Observation time: No effect (neutral)

4. Favored or disadvantaged organisms

Favored bioagressors

Organism	Impact of the technique	Type	Details
common bunt of wheat	MEDIUM	pathogen (bioagressor)	Late sowings are more easily contaminated because plants develop more slowly and reach the 2-leaf stage later, after which they are no longer sensitive.
cereal leaf miner	MEDIUM	pest, predator or parasite	Especially if preceded by beet or onion. Risk can be reduced by increasing sowing density and firming the seedbed.
pea thrips		pest, predator or parasite	For pea, late sowings and late varieties are particularly threatened by thrips.

Disfavored Bioagressors

Organism	Impact of the technique	Type	Details
White amaranth	MEDIUM	weeds
Blite amaranth	MEDIUM	weeds
Hybrid amaranth	MEDIUM	weeds
Reflective amaranth	MEDIUM	weeds
Theophrastus abutilon	MEDIUM	weeds
wind-play agrostis	LOW	weeds	Low effectiveness due to winter emergence.
Thalius rockcress	MEDIUM	weeds
common mugwort	MEDIUM	weeds
intermediate barbarée	MEDIUM	weeds
three-lobed bident	MEDIUM	weeds
irregular calepine	MEDIUM	weeds
bristly cardamine	MEDIUM	weeds
corn marigold	MEDIUM	weeds
wheat leafhopper	MEDIUM	pest, predator or parasite	Late sowing limits the establishment of the second generation in affected areas.
Nîmes hawkweed	MEDIUM	weeds
jimsonweed	MEDIUM	weeds
red digitgrass	MEDIUM	weeds
cicuta-leaved erodium	MEDIUM	weeds
small spurge	MEDIUM	weeds
common fennel	MEDIUM	weeds
cottony galactites	MEDIUM	weeds
tuberous vetchling	MEDIUM	weeds
field gromwell	MEDIUM	weeds
large-fruited velvetleaf	MEDIUM	weeds
round-leaved mint	MEDIUM	weeds
black nightshade	MEDIUM	weeds
field chickweed	MEDIUM	weeds
field forget-me-not	MEDIUM	weeds
hairy panicgrass	MEDIUM	weeds
false millet panicgrass	MEDIUM	weeds
crowfoot panicgrass	MEDIUM	weeds
dichotomous inflorescence panicgrass	MEDIUM	weeds
field passerage	MEDIUM	weeds
drave passerage	MEDIUM	weeds
venus comb	MEDIUM	weeds
ten-stamened phytolacca	MEDIUM	weeds
take-all	MEDIUM	pathogen (bioagressor)	On cereals.
sharp eyespot	HIGH	pathogen (bioagressor)	On cereals.
autumn aphid	HIGH	pest, predator or parasite	On cereals.
black bean aphid		pest, predator or parasite	If technique applicable to this crop.
pea green aphid		pest, predator or parasite	If technique applicable to this crop.
green and pink potato aphid		pest, predator or parasite
potato aphids		pest, predator or parasite	If technique applicable to this crop.
crucifer aphids		pest, predator or parasite	If technique applicable on crucifers.
aphids vectoring severe yellows		pest, predator or parasite	If technique applicable on beet.
aphids vectoring moderate yellows		pest, predator or parasite	If technique applicable on beet.
corn borer	LOW	pest, predator or parasite	Late sowing limits the establishment of the second generation in affected areas.
field buttercup	MEDIUM	weeds
bindweed knotweed	MEDIUM	weeds
brown rust	MEDIUM	pathogen (bioagressor)	On cereals.
crown rust		pathogen (bioagressor)	On winter oats.
stem rust		pathogen (bioagressor)	On winter rye.
yellow rust	MEDIUM	pathogen (bioagressor)	On cereals.
small dock rumex	MEDIUM	weeds
leaf septoria	LOW	pathogen (bioagressor)	On cereals.
hedge mustard	MEDIUM	weeds
pea weevil		pest, predator or parasite	Damage to nodules is greater in lentils fields sown early.
Aleppo sorghum	MEDIUM	weeds
Venus mirror specular	MEDIUM	weeds
glaucous setaria	MEDIUM	weeds
green setaria	MEDIUM	weeds
whorled setaria	MEDIUM	weeds
field torilis	MEDIUM	weeds
knotted torilis	MEDIUM	weeds
cereal mosaic virus		pathogen (bioagressor)
cereal mosaic virus	HIGH	pathogen (bioagressor)	On cereals.
rat's-tail fescue	MEDIUM	weeds
field vulpia	HIGH	weeds
field speedwell	MEDIUM	weeds

Auxiliaries favored

Organism	Impact of the technique	Type	Details

Disfavored auxiliaries

Organism	Impact of the technique	Type	Details

Favored climatic and physiological accidents

Organism	Impact of the technique	Details

Disfavored climatic and physiological accidents

Organism	Impact of the technique	Details

5. For more information

Delayed sowing date of winter cereals
-Pierre Mischler

Agro-Transfert Resources and Territories, Technical brochure, 2011

link to the brochure

Diseases and pests of open-field vegetables in Brittany
-Estorgues V. (Chamber of Agriculture of Finistère, coordination); vegetable advisors of the 4 chambers of agriculture of Brittany

Chambers of Agriculture of Brittany, Book, 2005

Wheat pests - Anticipating attacks of flies gray
-Gauthier C. (Terre-Net Media)

Terre-net.fr, published 10/20/2011, Press article, 2011

Article

Crop protection strategies saving phytosanitary products
-Gran Aymerich L.

Ministry of Agriculture and Fishing, University work, 2006

Engineering thesis. Sheet no. 8 of the thesis largely inspired this technical sheet.

6. Keywords

Bioagressor control method: Cultural control

Mode of action: Avoidance

Type of strategy regarding pesticide use: Redesign

Annexes

Est complémentaire des leviers

Perform false seedings during intercrop

Favorise les bioagresseurs suivants

Défavorise les bioagresseurs suivants

Sowing / transplanting late

Contents