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water from irrigation during the main growth phase, while ripening requires a dry
period (DAFF 2014). Well-drained, fertile sandy to clay soils with a pH between 6.0
and 7.7 are ideal for growing sugarcane (DAFF 2014).
1.2 Impact of Climate Change on Sugarcane Production
Many studies have focused on the impact climate change will have on various
aspects of sugarcane production (Jones et al. 2015; Zhao and Li 2015; Marin et al.
2014; Chandiposha 2013; Knox et al. 2010; Gawander 2007; Deressa et al. 2005).
Overall, these studies indicate that projected future temperatures will have no significant effect on sugarcane growth since the projected temperature increases are
within the crop’s optimum range (30–32 °C). High temperature scenarios will
enhance sugarcane growth and yield (Gawander 2007). However, temperatures
higher than 35 °C will negatively affect sugarcane germination and internode development (Rasheed et al. 2011; Bonnett et al. 2006). Higher temperature will also lead
to high evapotranspiration resulting in increased irrigation demands to minimize
crop losses. In addition, temperature under current climate change scenarios will
favour insect pests, weeds and certain fungal diseases (Matthieson 2007). However,
there is little attention on implications of climate variability on pesticide exposure
in sugarcane production. Chandiposha (2013) provided an account of how climate
change would influence pest occurrence and distribution. Responses to climate
change are usually long term. However, farmers have to respond to climate variability every season. Responses may include choice of crop and decisions on which
soil and water management practices to adopt, all of which have a bearing on pest
occurrence and severity. In addition, there is little focus on how an increased frequency of floods or rising temperatures will affect the efficacy and hazards posed by
pesticides and how farmers will respond to such changes. The main objective of this
review is therefore to bring into focus how climate variability affects the sugarcane
industry and the amount and exposure to pesticides used in sugarcane production
in Malawi.
We obtained information on pesticides, climate change and/or variability and its
effects on agriculture and pesticides in general from the wide variety of available
published literature as well as official and private documents.
2 Properties of Pesticides Used in Sugarcane Production
in Malawi
Several insects, weeds and pathogens, commonly referred to as pests, significantly
affect the production of sugarcane. Furthermore, climate scientists predict that climate change and/or variability will affect sugarcane production and the associated
pests. Pesticides are chemicals used to minimize yield losses caused by pests.
Pesticides for killing weeds (herbicides) and insect pests (insecticides) are the main
Impact of Climate Variability on the Use and Exposure of Pesticides in Sugarcane…
water from irrigation during the main growth phase, while ripening requires a dry
period (DAFF 2014). Well-drained, fertile sandy to clay soils with a pH between 6.0
and 7.7 are ideal for growing sugarcane (DAFF 2014).
1.2 Impact of Climate Change on Sugarcane Production
Many studies have focused on the impact climate change will have on various
aspects of sugarcane production (Jones et al. 2015; Zhao and Li 2015; Marin et al.
2014; Chandiposha 2013; Knox et al. 2010; Gawander 2007; Deressa et al. 2005).
Overall, these studies indicate that projected future temperatures will have no significant effect on sugarcane growth since the projected temperature increases are
within the crop’s optimum range (30–32 °C). High temperature scenarios will
enhance sugarcane growth and yield (Gawander 2007). However, temperatures
higher than 35 °C will negatively affect sugarcane germination and internode development (Rasheed et al. 2011; Bonnett et al. 2006). Higher temperature will also lead
to high evapotranspiration resulting in increased irrigation demands to minimize
crop losses. In addition, temperature under current climate change scenarios will
favour insect pests, weeds and certain fungal diseases (Matthieson 2007). However,
there is little attention on implications of climate variability on pesticide exposure
in sugarcane production. Chandiposha (2013) provided an account of how climate
change would influence pest occurrence and distribution. Responses to climate
change are usually long term. However, farmers have to respond to climate variability every season. Responses may include choice of crop and decisions on which
soil and water management practices to adopt, all of which have a bearing on pest
occurrence and severity. In addition, there is little focus on how an increased frequency of floods or rising temperatures will affect the efficacy and hazards posed by
pesticides and how farmers will respond to such changes. The main objective of this
review is therefore to bring into focus how climate variability affects the sugarcane
industry and the amount and exposure to pesticides used in sugarcane production
in Malawi.
We obtained information on pesticides, climate change and/or variability and its
effects on agriculture and pesticides in general from the wide variety of available
published literature as well as official and private documents.
2 Properties of Pesticides Used in Sugarcane Production
in Malawi
Several insects, weeds and pathogens, commonly referred to as pests, significantly
affect the production of sugarcane. Furthermore, climate scientists predict that climate change and/or variability will affect sugarcane production and the associated
pests. Pesticides are chemicals used to minimize yield losses caused by pests.
Pesticides for killing weeds (herbicides) and insect pests (insecticides) are the main
Impact of Climate Variability on the Use and Exposure of Pesticides in Sugarcane…