Enhancing smallholder farmers’ awareness of GM maize technology, management practices and compliance to stewardship requirements in the Eastern Cape Province of South Africa: the role of public extension and advisory services. 

Genetically modified (GM) maize technology adoption is subject to compliance with stewardship requirements that promote the long-term effectiveness of the technology against target pests and weeds. Awareness of the value of these requirements can enhance farmer compliance and promote the adoption of improved management practices. A semi-structured questionnaire was used to interview 210 smallholder GM maize farmers in the Eastern Cape to assess farmers’ awareness and compliance to GM maize technology stewardship requirements. Field surveys were also conducted to identify the practices adopted for the cultivation of GM maize. Results indicated that farmers lacked access to information about GM maize and had a low level of awareness of GM maize stewardship requirements. Additionally, while the use of Bt maize resulted in fewer farmers reporting pest incidence, notably that of the maize stem borer, Busseola fusca (Lepidoptera: Noctuidae) on their farms, for some reason, there was an increase in the proportion of farmers that sprayed and relied solely on insecticides for controlling pests on Bt maize. A high proportion of farmers (71.4%) also relied solely on herbicide sprays for controlling weeds in their herbicide tolerant maize fields. Field surveys also indicated non-compliance to the requirement for the planting of refuge areas adjacent to Bt maize. Training of extension service personnel on stewardship requirements for GM maize is urgently needed to improve its management and prevent loss of the benefits provided by GM maize technology.

Read more: http://www.scielo.org.za/pdf/sajae/v45n2/05.pdf

Rationalizing governance of genetically modified products in developing countries

This letter to the editor of Nature Correspondence highlights a number of reasons hindering uptake of genetically modified (GM) crops in developing countries. Largely based on the book Rationalizing governance of genetically modified products in developing countries” published by Cambridge University Press in 2018, the letter lists perceived risk, inefficient regulations among others as key hindrances to technology adoption despite the overwhelming evidence of substantial benefits of growing GM crops.

Read more: https://www.nature.com/articles/nbt.4069.epdf?author_access_token=88wxyN2a5OuknZBbDIJllNRgN0jAjWel9jnR3ZoTv0NMBb9z9jBT9-nEhp_3Le-T0dfy82jD62VY6x5u49WPvHH97uuCNkOeLntVOMR8u-NyoP96BOki-CjKmTGm4xmE

Genome-wide association mapping and genomic prediction for CBSD resistance in Cassava

Cassava (Manihot esculenta Crantz) is an important security crop that faces severe yield loses due to cassava brown streak disease (CBSD). Motivated by the slow progress of conventional breeding, genetic improvement of cassava is undergoing rapid change due to the implementation of quantitative trait loci mapping, Genome-wide association mapping (GWAS), and genomic selection (GS). In this study, two breeding panels were genotyped for SNP markers using genotyping by sequencing and phenotyped for foliar and CBSD root symptoms at five locations in Uganda. Our GWAS study found two regions associated to CBSD, one on chromosome 4 which co-localizes with a Manihot glaziovii introgression segment and one on chromosome 11, which contains a cluster of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes. We evaluated the potential of GS to improve CBSD resistance by assessing the accuracy of seven prediction models. Predictive accuracy values varied between CBSD foliar severity traits at 3 months after planting (MAP) (0.27–0.32), 6 MAP (0.40–0.42) and root severity (0.31–0.42). For all traits, Random Forest and reproducing kernel Hilbert spaces regression showed the highest predictive accuracies. Our results provide an insight into the genetics of CBSD resistance to guide CBSD marker-assisted breeding and highlight the potential of GS to improve cassava breeding.

Read more: https://www.nature.com/articles/s41598-018-19696-1.pdf