The fall armyworm (FAW, Spodoptera frugiperda) originates from the tropical and sub‐tropical regions of the Americas. Recently it was reported for the first time in Africa and has since spread rapidly across more than 30 countries in the continent. Chemical pesticides are being promoted and used for FAW management, but where application practices and/or the active ingredients are unsafe there is a need to make effective, low‐risk products available. Given that biopesticides such as microbials and microbial extracts, macrobials and semiochemicals are generally considered to be lower risk options for pest management, they are a promising avenue for exploration. When used in conjunction with good crop management, they can help to keep pest levels under control, reducing the need to apply other pesticides. This study provides a basis for designing interventions to make biopesticides more widely available for FAW control in Africa. It summarizes assessments of the registered pesticides and biopesticides for 30 countries, 11 in FAW's native range and 19 in Africa. The report identifies biopesticide active ingredients (AI) which are registered for use against FAW and provides an assessment of how appropriate these will be for use by smallholder farmers in Africa. For each biopesticide AI identified, detailed profiles were developed which covered the efficacy of the AI against FAW; the human health and environmental hazards associated with the AI; the agronomic sustainability of the AI; and whether or not the AI is practical for smallholder farmers to use. Using these data, a list of priority biopesticides for which follow‐up action is recommended was compiled. Fifty biopesticide AI were identified, which have been registered in one or more of the 30 countries for FAW management. Twenty‐three of these are recommended for follow‐up, for example field trials or bioassays.
Understanding the progression of host–pathogen interaction through time by hyperspectral features is vital for tracking yellow rust (Puccinia striiformis) development, one of the major diseases of wheat. However, well-designed features are still open issues that impact the performance of relevant models to nondestructively detect pathological progress of wheat rust. The aim of this paper is (1) to propose a novel wavelet-based rust spectral feature set (WRSFs) to uncover wheat rust-related processes; and (2) to evaluate the performance and robustness of the proposed WRSFs and models for retrieving the progression of host–pathogen interaction and tracking rust development. A hyperspectral dataset was collected by analytical spectral devices (ASD) spectroradiometer and Headwall spectrograph, along with corresponding physiological measurements of chlorophyll index (CHL), nitrogen balance index (NBI), anthocyanin index (ANTH), and percentile dry matter (PDM) from the 7th to 41st day after inoculation (dai) under controlled conditions. The resultant findings suggest that the progression of yellow rust on wheat is better characterized by the proposed WRSFs (R2 > 0.7). The WRSFs-based PLSR model provides insight into specific leaf biophysical variations in the rust pathological progress. To evaluate the efficiency of the proposed WRSFs on yellow rust discrimination during different infestation stages, the identified WRSFs and vegetation indices (VIs) were fed into linear discriminant analysis (LDA) and support vector machine (SVM) classification frames. The WRSFs in conjunction with a SVM classifier can obtain better performance than that of LDA method and the VIs-based models. Overall, synthesizing the biophysical analysis, retrieving accuracy, and classification performance, we recommend the proposed WRSFs for monitoring the progression of the host–pathogen interaction of yellow rust on wheat cross various hyperspectral sensors.
The fall armyworm (FAW, Spodoptera frugiperda) has recently spread to many countries in Africa, the Near East, Asia and the Pacific. In sub‐Saharan Africa (SSA), more than 300 million people depend on FAW’s preferred host plant, maize, as a staple crop. Hence, the spread of FAW in SSA has the potential to negatively affect livelihoods and food security. Many farmers have responded to FAW by increasing their use of synthetic pesticides, but these are not always used safely or effectively. More information on sustainable alternatives to high‐risk synthetic pesticides is needed to inform decisions by farmers and policy makers. In a previous paper, the authors responded to this information need by identifying fifty biopesticides which had been registered for FAW management in one or more of 30 countries in FAWs native region and Africa. For each biopesticide identified, detailed profiles with information on their efficacy against FAW; associated human health and environmental hazards; their agronomic sustainability; and whether or not they are practical for use by smallholder farmers were developed Research for development (R4D) efforts is ongoing in Africa and Asia for development and use of biopesticides for FAW management. Hence, in this study the authors assessed the current state of knowledge and documented how information gaps have been filled (or not) since the previous paper was published. The authors found that for many biopesticides there is a growing body of information on their efficacy in the field in Africa and increased availability of commercialized products. They also note remaining information gaps, particularly the compatibility of the biopesticides with other recommended management practices, and cost‐benefit analyses, important for developing and implementing sustainable IPM. An updated list of priority biopesticides for research, development and promotion is provided.
Using qualitative methods, this study assessed the stakeholders and management processes involved in locust outbreaks in China, including factors influencing the use of biopesticides. Study findings show that China has an integrated national locust response protocol, which involves various institutions from all administrative levels of the government. The process is inherently highly complex but efficient, with multisectoral agencies working closely together to prevent and/or manage locust outbreaks. In addition, the process has been successful in combating recent outbreaks, due to dedicated government funding, decisive administrative and technical actions, and the empowerment of local government administration. This is the case with the county level acting as a ‘first-responder’ that is capacitated financially and technically to respond to a locust invasion in their jurisdiction. Additionally, study findings show that despite the availability of biopesticides in local markets, their use is dampened by inadequate information about market availability, negative perceptions by decision makers about their efficacy, and concerns about their costs, as well as limited knowledge of their application techniques. Actions are therefore needed by relevant authorities to enhance stakeholder awareness of biopesticide market availability, efficacy, and field application processes. Future areas of research should focus on modelling the expected impact and cost effectiveness of chemicals vs. biopesticides, thus increasing the evidence base for promoting biopesticide use.
The production of tomato in Pakistan is affected by Helicoverpa armigera, which causes significant crop loss. Farmers mostly use insecticides to control the pest, but an excessive and indiscriminate use of these products has resulted in environmental and health hazards. Trichogramma is promoted as an alternative bio-control method. This study aimed to look at gender-related barriers against the uptake of Trichogramma by farmers in the Punjab, Sindh, and Khyber Pakhtunkhwa provinces of Pakistan. Key-informant interviews were conducted with the researchers and agricultural extension staff involved in the dissemination of this technology. In-depth interviews and focus-group discussions were carried out with female and male farmers using Trichogramma and with non-using farmers. Results showed that communicating directly with women about the bio-control method helped to improve uptake by farming households. The reduced health risks of the bio-control method was important for female farmers, while male farmers were more concerned about the effectiveness of the bio-control method compared with pesticides. Using Trichogramma helped to reduce the time and labour spent by men on pest management and improved their yield and income. However, it increased the demand on women’s time and labour while their decision-making roles regarding the income from tomato production remained low. A lack of information, training, and reliable supply were the main reasons non-using farmers had for not using Trichogramma.