Why don't smallholder farmers in Kenya use more biopesticides?

BACKGROUND: Although Kenya has a relatively high number of registered biopesticide products, little is known about biopesticide use by smallholders. This paper documents farmers' current use and perception of chemical pesticides and biopesticides, their willingness to pay for biopesticides, and the key challenges to biopesticide uptake. RESULTS: A survey found that chemical pesticides are used widely by smallholders despite awareness of the risks to human health and the environment. Almost half of respondents showed awareness of biopesticides, but current use in the survey localities was low (10%). Key reasons for the low use of biopesticides by smallholders in this study are: perceptions of effectiveness, primarily speed of action and spectrum of activity, availability and affordability. Smallholders who used biopesticides cited effectiveness, recommendation by advisory services and perception of safety as key reasons for their choice. Although farmers viewed both pesticides and biopesticides as costly, they invested in the former due to their perceived effectiveness. Average willingness to pay, above current chemical pesticide expenditures per cropping season was 9.6% (US$5.7). Willingness to pay differed significantly between counties, and was higher among farmers with more education or greater awareness of the health risks associated with pesticide use. CONCLUSION: This study confirms the low use of biopesticide products in the survey areas, alongside high use of conventional chemical pesticides. In order to promote greater uptake of biopesticides, addressing farmers' awareness and their perceptions of effectiveness is important, as well as increasing the knowledge of those providing advice and ensuring registered products are available locally at competitive prices. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Reaching for the low hanging fruits: One health benefits of joint crop-livestock services for small-scale farmers.

The benefits of joint health service delivery remain under-explored in One Health. Plant clinics are known to provide ad hoc, undocumented advice on animal health and production to farmers. To understand the scope of this activity, 180 plant doctors (extension workers) in Uganda, Kenya, Zambia, Peru and Costa Rica were surveyed and a workshop involving key stakeholders was organized in Uganda. Most (81%) plant doctors regularly received queries from farmers on livestock topics. This shows that the single sectoral approach to service delivery often does not match small-scale farmers' needs. There is growing interest among service providers, ministry officials and researchers to improve integration of farmer services to reduce operational costs and make better use of existing capacities. The workshop supported the proposal for the first 'crop-livestock clinics' to be trialled and evaluated in Uganda. This will inform other countries on the potential of joint services to mixed crop-livestock farming communities.

Spatial and temporal transcriptomic analysis of the Arabidopsis thaliana-Botrytis cinerea interaction.

Plants activate an array of defence responses following recognition of pathogenic organisms. This study attempted to characterize at a transcriptional level, the defence responses of Arabidopsis thaliana after infection with Botrytis cinerea using microarrays. Alteration in transcript levels following infection was investigated in time (temporal) and space (spatial). A number of genes were up- and down-regulated specifically at 12 h, others at 24 h while others were up- and down-regulated at both time points. Similarly, some genes were specifically induced very close to the lesion while others in more distal tissue. Clustering of expression profiles resulting from other biotic and abiotic interactions with Arabidopsis indicated a large overlap in gene expression. This study highlighted a multitude of genes induced in Arabidopsis spatially and temporally following infection with B. cinerea providing an insight into key processes of defence against this pathogen. The plethora of altered genes identified are candidates for further investigation.

Metabolomic approaches reveal that cell wall modifications play a major role in ethylene-mediated resistance against Botrytis cinerea.

In Arabidopsis, resistance to the necrotrophic fungus Botrytis cinerea is conferred by ethylene via poorly understood mechanisms. Metabolomic approaches compared the responses of the wild-type, the ethylene-insensitive mutant etr1-1, which showed increased susceptibility, and the constitutively active ethylene mutants ctr1-1 and eto2 both exhibited decreased susceptibility to B. cinerea. Fourier transform-infrared (FT-IR) spectroscopy demonstrated reproducible biochemical differences between treatments and genotypes. To identify discriminatory mass-to-charge ratios (m/z) associated with resistance, discriminant function analysis was employed on spectra derived from direct injection electrospray ionisation-mass spectrometry on the derived principal components of these data. Ethylene-modulated m/z were mapped onto Arabidopsis biochemical pathways and many were associated with hydroxycinnamate and monolignol biosynthesis, both linked to cell wall modification. A high-resolution linear triple quadrupole-Orbitrap hybrid system confirmed the identity of key metabolites in these pathways. The contribution of these pathways to defence against B. cinerea was validated through the use of multiple Arabidopsis mutants. The FT-IR microspectroscopy indicated that spatial accumulation of hydroxycinnamates and monolignols at the cell wall to confine disease was linked ot ethylene. These data demonstrate the power of metabolomic approaches in elucidating novel biological phenomena, especially when coupled to validation steps exploiting relevant mutant genotypes.