Agricultural biotechnology and smallholder farmers in developing countries

An Empirical Study of Regulatory Capture in Kenya's Maize Seed Sector

In sub-Saharan Africa, public sector breeding programs depend on local seed companies to deliver new maize varieties to farmers. Such varieties are needed to adapt cropping systems to climate change. While dozens of small and medium seed companies have emerged in the last two decades, the maize seed market in Kenya remains dominated by the parastatal seed company Kenya Seed Company, with multinational seed companies making major inroads. We assess whether parastatal and multinational seed companies have captured Kenya's seed laws to the detriment of local small and medium seed companies ('regulatory capture'), negatively effecting competition and the capacity of local companies to introduce new varieties in the hybrid maize seed market. We conducted in-depth interviews based on legal clauses with maize seed companies active in Kenya, as well as interviews with regulators and stakeholders. Results show that local companies do not feel disadvantaged compared to their multinational counterparts or the parastatal. However, all of them are wary of the entry of new actors. Moreover, through excessive procedures, the Kenyan government keeps a sovereign grasp over the seed sector. Despite frustrations with some of these excessive procedures, seed companies felt comfortable in the protective environment of the Kenyan seed market and were generally happy with the technical aspects of Kenya's seed laws, which are based on international norms. We suggest some improvements to make Kenyan seed laws more conducive to varietal turnover, in line with seed companies' suggestions and taking into account the political sensitivities of the Kenyan government.

Microbial Responses to the Reduction of Chemical Fertilizers in the Rhizosphere Soil of Flue-Cured Tobacco

The overuse of chemical fertilizers has resulted in the degradation of the physicochemical properties and negative changes in the microbial profiles of agricultural soil. These changes have disequilibrated the balance in agricultural ecology, which has resulted in overloaded land with low fertility and planting obstacles. To protect the agricultural soil from the effects of unsustainable fertilization strategies, experiments of the reduction of nitrogen fertilization at 10, 20, and 30% were implemented. In this study, the bacterial responses to the reduction of nitrogen fertilizer were investigated. The bacterial communities of the fertilizer-reducing treatments (D10F, D20F, and D30F) were different from those of the control group (CK). The alpha diversity was significantly increased in D20F compared to that of the CK. The analysis of beta diversity revealed variation of the bacterial communities between fertilizer-reducing treatments and CK, when the clusters of D10F, D20F, and D30F were separated. Chemical fertilizers played dominant roles in changing the bacterial community of D20F. Meanwhile, pH, soil organic matter, and six enzymes (soil sucrase, catalase, polyphenol oxidase, urease, acid phosphatase, and nitrite reductase) were responsible for the variation of the bacterial communities in fertilizer-reducing treatments. Moreover, four of the top 20 genera (unidentified JG30-KF-AS9, JG30-KF-CM45, Streptomyces, and Elsterales) were considered as key bacteria, which contributed to the variation of bacterial communities between fertilizer-reducing treatments and CK. These findings provide a theoretical basis for a fertilizer-reducing strategy in sustainable agriculture, and potentially contribute to the utilization of agricultural resources through screening plant beneficial bacteria from native low-fertility soil.

Digitalization in Food Supply Chains: A Bibliometric Review and Key-Route Main Path Analysis

Technological advances such as blockchain, artificial intelligence, big data, social media, and geographic information systems represent a building block of the digital transformation that supports the resilience of the food supply chain (FSC) and increases its efficiency. This paper reviews the literature surrounding digitalization in FSCs. A bibliometric and key-route main path analysis was carried out to objectively and analytically uncover the knowledge development in digitalization within the context of sustainable FSCs. The research began with the selection of 2140 articles published over nearly five decades. Then, the articles were examined according to several bibliometric metrics such as year of publication, countries, institutions, sources, authors, and keywords frequency. A keyword co-occurrence network was generated to cluster the relevant literature. Findings of the review and bibliometric analysis indicate that research at the intersection of technology and the FSC has gained substantial interest from scholars. On the basis of keyword co-occurrence network, the literature is focused on the role of information communication technology for agriculture and food security, food waste and circular economy, and the merge of the Internet of Things and blockchain in the FSC. The analysis of the key-route main path uncovers three critical periods marking the development of technology-enabled FSCs. The study offers scholars a better understanding of digitalization within the agri-food industry and the current knowledge gaps for future research. Practitioners may find the review useful to remain ahead of the latest discussions of technology-enabled FSCs. To the authors’ best knowledge, the current study is one of the few endeavors to explore technology-enabled FSCs using a comprehensive sample of journal articles published during the past five decades.

Circular DNA enrichment sequencing reveals the viral/satellites genetic diversity associated with the third epidemic of cotton leaf curl disease

Cotton leaf curl disease (CLCuD) is the most important limiting factor for cotton production in Pakistan. The CLCuD passed through two major epidemics in this region with distinct begomoviruses/satellites complexes. Since 2015 the disease has again started to appear in epidemic form, causing heavy losses to cotton crop, which we termed as the “third epidemic”. We applied CIDER-seq (Circular DNA Enrichment Sequencing), a recently developed sequencing method for PCR-free virus enrichment to produce a full length read of a single circular viral genome coupled with Sanger sequencing to explore the genetic diversity of the disease complex. We identified a highly recombinant strain of Cotton leaf curl Multan virus and a recently evolved strain of Cotton leaf curl Multan betasatellite that are dominant in all major cotton growing regions in the country. Moreover, we also identified multiple species of alphasatellites with one distinct species, Mesta yellow vein mosaic alphasatellite (MeYVMA) for the first time in cotton. Relative abundance of virus and associated satellites was also determined by real-time quantitative PCR. To the best of our knowledge, this is the first study that determined the CLCuD complex associated with its third epidemic.

Metagenomic analysis of relative abundance and diversity of bacterial microbiota in Bemisia tabaci infesting cotton crop in Pakistan

B. tabaci species complex are among the world's most devastating agricultural pests causing economic losses by direct feeding and more importantly by transmitting plant viruses like cotton leaf curl disease (CLCuD) associated viruses to cultivated cotton in Pakistan. Taxonomic diversity of B. tabaci associated bacterial communities using NGS techniques so far is reported from insects grown on artificial diet under lab conditions. In this study 16S rDNA metagenome sequencing analysis was used to characterize bacterial compositions in wild adult B. tabaci infesting cultivated cotton in eight major cotton growing districts of southern Punjab, Pakistan. We have identified 50 known and 7 unknown genera of bacteria belonging to 10 phyla, 20 classes, 30 orders and 40 families. Beta diversity analysis of our data sets reveal that whiteflies infesting cotton in geographically distinct locations had similar bacterial diversity. These results for the first time provide insights into the microbiome diversity of wild type whiteflies infesting a cultivated crop.

Non-cultivated Cotton Species (Gossypium spp.) Act as a Reservoir for Cotton Leaf Curl Begomoviruses and Associated Satellites

A collection of cultivated and non-cultivated species of cotton (Gossypium spp.) has been maintained for the last four decades in Multan, Pakistan. This geographical location has been observed as a hotspot for the evolution of begomoviruses and satellites associated with cotton leaf curl disease (CLCuD). Recent studies showed that begomoviruses responsible for the CLCuD epidemic in the 1990s, and that almost disappeared from the CLCuD complex in 2000s, have been observed again in CLCuD-infected cotton fields. To identify host species that acted as probable reservoirs for these viruses, we characterized begomoviruses and satellites in non-cultivated cotton species G. raimondii, G. thurberi and G. mustelinum and identified several species of CLCuD associated begomoviruses and satellites. Further, phylogenetic analysis indicated that the identified begomoviruses and beta/alphasatellites are closely related to the ones associated with the most recent CLCuD complex. qPCR indicated that the comparative level of virus significantly decreased in the presence of alphasatellites. Our results indicated that non-cultivated cotton species have been continuously challenged by diverse begomoviruses and associated satellites and act as reservoirs for CLCuD associated begomoviruses. These results provide novel insights into understanding the spread of begomoviruses and associated satellites in New World cotton species introduced into the Old World.

Multiple begomoviruses found associated with cotton leaf curl disease in Pakistan in early 1990 are back in cultivated cotton

The first epidemic of cotton leaf curl disease (CLCuD) in early 1990's in the Indian subcontinent was associated with several distinct begomoviruses along with a disease-specific betasatellite. Resistant cotton varieties were introduced in late 1990's but soon resistance was broken and was associated with a single recombinant begomovirus named Burewala strain of Cotton leaf curl Kokhran virus that lacks a full complement of a gene encoding a transcription activator protein (TrAP). In order to understand the ongoing changes in CLCuD complex in Pakistan, CLCuD affected plants from cotton fields at Vehari were collected. Illumina sequencing was used to assess the diversity of CLCuD complex. At least three distinct begomoviruses characterized from the first epidemic; Cotton leaf curl Multan virus, Cotton leaf curl Kokhran virus and Cotton leaf curl Alabad virus, several distinct species of alphasatellites and cotton leaf curl Multan betasatellite were found associated with CLCuD. These viruses were also cloned and sequenced through Sanger sequencing to confirm the identity of the begomoviruses and that all clones possessed a full complement of the TrAP gene. A new strain of betasatellite was identified here and named CLCuMuB^Veh. The implications of these findings in efforts to control CLCuD are discussed.

A multidisciplinary research agenda for the acceptance of Golden Rice

Purpose

The world is facing serious global food security challenges such as the need for sufficient food for a growing population and an exponential growth in nutrient deficiency disorders. Agricultural biotechnology, such as genetically modified (GM) crops, offers itself as a promising solution to address one or more of these issues. Golden Rice (GR) is an example of a GM crop which contains high amount of β-carotene, a compound which is an antioxidant and a precursor of vitamin A. In spite of GR’s promised potential benefits in combating vitamin A deficiency (VAD) disorders it is still not cultivated. This viewpoint paper aims to present the reader with a need for multidisciplinary research agenda, the outcomes of which can contribute towards the acceptance of GR.

Design/methodology/approach

This viewpoint paper is based on an extensive literature review to identify the “gaps” which contributed to low acceptance of GR. This paper presents a systematic discussion on the importance of GR in tackling VAD and discusses controversies around GR and a scientific approach to tackle them.

Findings

The literature review clearly indicates that there is a huge gap in information substantiating the potential of GR for consumers as well as for the farming community. Addressing these issues can substantially increase the acceptance and cultivation of GR. This viewpoint paper proposes food technologists’ and social scientists’ research agenda for GR and further indicates how the involvement of other research disciplines can improve the acceptance of GR.

Originality/value

The literature review indicates the potential of GR in tackling VAD disorders but clearly lacks information to substantiate these arguments. This paper presents authors’ opinions, urging scientists to take up a multidisciplinary research approach to emancipate GR from the clutches of GM food controversies.

Dominant inheritance of field-evolved resistance to Bt corn in Busseolafusca

Transgenic crops expressing Bacillus thuringiensis (Bt) toxins have been adopted worldwide, notably in developing countries. In spite of their success in controlling target pests while allowing a substantial reduction of insecticide use, the sustainable control of these pest populations is threatened by the evolution of resistance. The implementation of the “high dose/refuge” strategy for managing insect resistance in transgenic crops aims at delaying the evolution of resistance to Bt crops in pest populations by promoting survival of susceptible insects. However, a crucial condition for the “high dose/refuge” strategy to be efficient is that the inheritance of resistance should be functionally recessive. Busseolafusca developed high levels of resistance to the Bt toxin Cry 1Ab expressed in Bt corn in South Africa. To test whether the inheritance of B. fusca resistance to the Bt toxin could be considered recessive we performed controlled crosses with this pest and evaluated its survival on Bt and non-Bt corn. Results show that resistance of B. fusca to Bt corn is dominant, which refutes the hypothesis of recessive inheritance. Survival on Bt corn was not lower than on non-Bt corn for both resistant larvae and the F₁ progeny from resistant × susceptible parents. Hence, resistance management strategies of B. fusca to Bt corn must address non-recessive resistance.