Emerging potato pathogens affecting food security in southern Africa: Recent research

Abstract

Potato is a staple crop that contributes to food security and poverty alleviation in developing nations. Despite this, yields in developing nations are often unsustainably low, due to various biotic and abiotic factors that negatively affect production. Some of the most important biotic constraints are pathogens, many of which are disseminated by seed tubers. The lack of functional or formal seed certification systems in many southern African countries results in a continual increase in pathogen pressure. Short rotation cycles, poor plant nutrition and inefficient control measures exacerbate the crop production challenges faced by resource poor growers. In this review, we discuss five of the most important diseases on potatoes in southern Africa, namely late blight, bacterial wilt, soft rot / blackleg, powdery scab and zebra chip. Management options for small-scale growers are provided.

Can we control potato fungal and bacterial diseases? — microbial regulation

“…Finally, symptoms extend to petioles and stalks, leading to plant death ( Fig. 2 a,b,c,d) [ 6 ]. Phytophthora infestans is a devastating pathogen causing late potato blight.…”

“…2 Symptoms of infection of potato pathogenic diseases. (a) (b) represent late blight infections in the field, (c) represents late blight infection in potato tubers, (d) represents late blight infection in pots, (e) represents soft rot infection in potatoes tubers, (f) represents blackleg infection in the field, (g) represents common scab infection in potato tubers, (h) represents powder scab infection in potato tubers [ 6 , [23] , [24] , [25] ]. …”

“…The symptoms of common potato scab and powdery scab are indistinguishable. Therefore, accurate identification of symptoms is critical for disease management and control [ 6 ]. Powdery scab caused by Spongiospora subterranean .…”

“… Fungi [ 5 ] Powdery scab Spongospora subterranean , Streptomyces spp. Fungi [ 6 , 9 ] Bacterial wilt Ralstonia solanacearum Bacteria [ 10 , 11 ] Soft rot/blackleg disease complex Pectobacterium, Pectobacterium Brasiliense, Dickeya, R. solanacearum Bacteria [ 6 ] Common Scab Streptomyces scabiei, S. acidiscabiei, S. turgidiscabiei Bacteria [ 1 , [12] , [13] , [14] , [15] ] Zebra chip disease Candidatus Liberibacter solanacearum Bacteria [ 6 , [16] , [17] , [18] ] …”

Eukaryotic translation initiation factor 4E family member nCBP facilitates the accumulation of TGB-encoding viruses by recognizing the viral coat protein in potato and tobacco

“…Potato ( Solanum tuberosum L.) is currently the third most important food crop worldwide next to rice and wheat for direct human consumption and food security ( Hardigan et al, 2017 ; van der Waals and Krüger, 2020 ). However, plant viruses are one of the main limiting factors leading to a loss in quality and quantity of potato ( Wang et al, 2011 ; Rashid et al, 2021 ).…”