Impact of climate and management on coffee berry disease and yield in Arabica coffee’s native range

• Climate change might increase plant diseases, reduce crop yields and threaten the livelihoods of millions of smallholder farmers globally. It is thus important to understand the relationships between climate, disease levels and yield to improve management strategies for sustainable agroforestry in a changing climate. One of the major threats to coffee production in Africa is coffee berry disease, caused by the fungal pathogen Colletotrichum kahawae. To investigate the effects of climatic and management variables on coffee berry disease and yield, we recorded daily minimum and maximum temperature and relative humidity, as well as incidence of coffee berry disease and yield in 58 sites along a broad environmental and management gradient in southwestern Ethiopia in both 2018 and 2019. Coffee berry disease was affected by several climatic and management variables, with relatively high consistency between years. For example, coffee berry disease incidence was higher in sites with high minimum temperatures during the fruit expansion stage from March to April, and was lower in sites with high minimum temperatures during the endosperm filling stage from May to June. Coffee berry disease incidence was negatively affected by the proportion of resistant cultivars, whereas management intensity had no effect on disease incidence. Coffee yield decreased with increasing minimum and maximum temperatures during the flowering period in 2018 and the fruit developmental period in 2019, respectively. Coffee yield was negatively affected by canopy cover, and positively affected by management intensity, in both years. Our findings highlight that coffee berry disease and yield were affected by different climatic and management variables. Yet, managing for low disease-high yield is practically difficult, as the effect of several climatic variables was season-dependent, and at the same time climatic variables were highly correlated between seasons. One way to break the correlation of climatic variables between seasons might be to take advantage of differences among shade trees in the presence or timing of leaf drop. To reduce levels of coffee berry disease, an effective strategy is to use resistant cultivars, but this might threaten the wild coffee genetic reservoir.

Ämnesord

LANTBRUKSVETENSKAPER  -- Lantbruksvetenskap, skogsbruk och fiske -- Jordbruksvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agriculture, Forestry and Fisheries -- Agricultural Science (hsv//eng)

Nyckelord

Climate change

coffee berry disease

management intensity

minimum and maximum temperature

relative humidity

yield

Ecology and Evolution

ekologi och evolution

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)