Effects of reduced pesticide use on flora and fauna in agricultural fields

Table 5.2.
Percentage increases (+) and decreases (-) in weed density, species richness, efficiency and yield at reduced or zero dosages compared to mean values at normal dosage. Significant difference from normal dosage is indicated as follows: +: 0.05£ p<0.10, *: 0.01£ p<0.05, **: 0.001£ p<0.01 and ***: p<0.001.

     

   

Dosage

Response variable

Crop

Normal

Half

Quarter

Zero

Weed density

Spring barley

103 plants/m2

+ 16 %

**

+ 29 %

***

+ 72 %

***

Winter wheat

35 plants/m2

+ 47 %

*

+ 65 %

**

+ 174 %

***

Species richness

Spring barley

5.2

+ 15 %

**

+ 13 %

**

+ 19 %

**

Winter wheat

2.8

- 0.9 %

 

- 1.2 %

 

+ 16 %

 

Efficiency

Spring barley

40 %

- 13 %

 

- 37 %

***

- 85 %

***

Winter wheat

46 %

- 32 %

 

- 39 %

+

- 101 %

***

Yield

Spring barley

6.4 t/ha

- 0.2 %

 

- 1.8 %

*

- 8.1 %

***

Winter wheat

9.6 t/ha

- 1.3 %

 

- 2.3 %

 

- 6.6 %

***