Crop Protection Online - now also including maize

Per RydahlDanish Institute of Agricultural

Sciences

Contents

• Status

• Introduction to model

• Prototypes in maize

• User interfaces

Status

Status (1)

• Crops:– 3 spring cereal crops– 4 winter cereal crops– spring- and winter oilseed rape– field pea– sugar beet

Status (2)

• Herbicides: – all registered and marketed products

• Weeds: – 75 species

• Subscribers in Denmark: – 1000 farmers– 300 consultants – 200 schools, companies etc.

• System export:– Estonia, Latvia, Lithuania, Poland and Norway

Introduction to model

Model function

1. assesses the level of weed control needed

2. selects single herbicides and calculates doses needed

3. calculates tank-mixtures, optimised for cost or TFI

4. strategy-module for multiple treatments

Step 1: The level of control needed

• Includes aspects on yield, quality and crop rotation• Based on expert knowledge• Input:

– Crop name – Season– Expected yield– Weed name– Weed density

• Output: – level of control needed on weed biomass,

4-6 weeks after a herbicide application (0-97%)

Step 2: dose-response function1 herbicide, 1 weed

0

50

100

Rate

Effi

cacy

(%

)

1/4 N 1/2 N 1/1 N 2/1 N

Step 2: dose-response function

Integration

0

50

100

0,0 0,1 1,0 10,0

Rate

Eff

icac

y (%

)

susceptible speciessm all weedswarm weather

less susc. speciesbig weedscold weather

Step 2: dose-response function

1 herbicide, 3 weed species

0

50

100

0,01 0,10 1,00 10,00Rate

Eff

ica

cy

(%

)

Species A

Species B

Species C

Actual dose

Efficacy target level

Step 3: ‘Tankmixtures’ Additive Dose Model (ADM)

Herbicide A:

0

50

100

0,0 0,1 1,0 10,0

Rate herbicide A

Effi

cacy

(%)

ADM (70%)

Synergism

Antagonism

ED70 Herbicide A

ED70

Herbicide B

Herbicide B:

0

50

100

0,0 0,1 1,0 10,0

Rate herbicide B

Effi

cacy

(%)

Sp 1

Dose Herbicide A

Dose Herbicide B

Sp 2

Sp 3

Sp 4

a

b

cd

Line (a,b),(b,c),(c,d) = ’Border isobole’

Step 3: ‘Tankmixtures’ Optimization

Prototypes in maize

Tasks

• to develop and validate DSS models for weed control in maize

• to achieve sufficient and safe control of weeds

• to quantify potentials

Reuse of components from cereals

• target effect levels:– expert model

• dose/response functions: – weed species (field data)– weed growth stages (semifield data)– temperature,

relative air humidity and water stress (semifield data)

• ADM (semifield data)

Reuse of components from sugar beet

• strategy:– spray subsequent flushes of emerged weeds

• repeated:– field inspections

– consultations of model

– sprayings, as recommend by model

• dose/response functions:– data from ’genuine’ split-applications

of single herbicides

Prototypes

• 3 prototypes with 3 levels of aimed efficacy:– ’90%-version’

– ’85%-version’

– ’80%-version’

• questions to answer in field validation tests:– can treatment options be recommended by model?

– is yield and weed control at satisfactory levels?

– can input of herbicides be reduced?

Efficacy 4-6 weeks after treatment

    Efficacy on weed density (%)

Year No. of trials

Un- treated(no./m2)

2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 402 100 99 97 -

2004 4 92 92 - 92 80

2005 5 166 95 - 93 90

W.m. 14 229 96 99 94 86

Efficacy at harvest (1)

    Total weed cover (%)

Year No. of trials

Un- treated

2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 89 1 3 6 -

2004 4 72 2 - 7 7

2005 5 85 3 - 4 3

W.m. 14 83 2 3 6 5

Efficacy at harvest (2)

    No. of trials with >15% total weed cover

Year No. oftrials

Un-treated

Ref. 2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 5 0 0 0 -

2004 4 4 0 - 1 0

2005 5 5 0 - 0 0

W.m. 14 14 0 0 0 0

Yields

*) No significant differences between treatments

    Hkg dry matter per hectare

Year No. of trilas

Un- treated

2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 - - - - -

2004 *) 4 50,3 59,6 - 58,2 56,8

2005 5 - - - - -

Treatment Frequency Index (TFI)

    TFI

Year No. oftrials

2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 1,13 0,97 0,86 -

2004 4 1,13 - 1,03 0,87

2005 5 1,13 - 1,22 1,13

W.m. 14 1,13 0,97 1,04 1,01

Costs of herbicides

    DKK per hectare

Year No. of trials

2 x Calaris

0,75 l/ha

90% 85% 80%

2003 5 726 697 480 -

2004 4 726 - 598 512

2005 5 720 - 578 597

W.m. 14 724 697 581 559

Conclusions on prototypes in maize

• considerable variation in weed infestations in validation test plots

• satisfactory weed control was achieved by all prototypes in all tests

• input of herbicides by 85%-version and 80%-version:– about 10% reduction of TFI – about 20% reduction of cost (about 160 DKK/ha)

• slightly revised 80%-version will be integrated in the official version of CPO in 2006

User interfaces

User interface - input www.planteinfo.dk

User interface - output