By Janet Kanters, Editor
There is great potential for the use of natural compounds – “plant extracts” – in agriculture, as evidenced not only by ongoing research, but by the introduction and use of new biological products in agriculture created by these plant extracts.
Plant extracts are derived from different plant parts, such as seeds, fruits, flowers, stems, leaves and roots, and can possess antifungal, antimicrobial and antiparasitic compounds that, in turn, are used for the manufacture of biostimulants and biopesticides.
The application of these bioproducts could be beneficial for sustainable production, due to several advantages, such as low toxicity to humans and the environment, enhanced resistance of cultivated plants to biotic and abiotic stress, increased yields and quality of crops, as well as the reduction in the use of mineral fertilizers and pesticides.
A paper published in 2021 in the Italian Journal of Agronomy provided an overview of the impact of plant-derived extracts/biostimulants (PDBs) on crops. In their research, Domenico Ronga (pharmacy department, University of Salerno, Fisciano (SA), Italy), Katarzyna Godlewska (department of horticulture, faculty of life sciences and technology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland), and Izabela Michalak (department of advanced material technologies, faculty of chemistry, Wrocław University of Science and Technology, Wrocław, Poland), found that the applications of PDBs may have a beneficial impact on plant growth, productivity, quality and tolerance to various biotic and abiotic stresses.
PDBs represent a new generation of products and an eco-friendly complement to widely used agrochemicals.
“PDBs represent a new generation of products and an eco-friendly complement to widely used agro-chemicals,” noted the authors. “In the coming few years, we can expect that plant biostimulants, including both natural and synthetic substances, as well as microbial inoculants, will not only make a significant contribution to ecologically and economically sustainable crop production systems within more resilient agro-ecosystems, but will also lay the cornerstone for a future large-scale sustainable agriculture catalyzed by the bio-based industry.”
Plant extracts can act as natural biostimulants of plant growth or biopesticides because they represent a rich source of bioactive compounds. However, the detailed composition of plant extracts, especially used in field trials, remains to be investigated.
The detailed composition of plant extracts, especially used in field trials, remains to be investigated.
“The chemical composition of the biomass itself is studied much more often than the obtained extracts,” noted the study’s authors. “Generally, the stimulating properties of plant extracts are attributed to organic compounds such as polyphenols, amino acids, plant hormones and vitamins, as well as micro- and macro-elements.”
Plant extracts as plant protection products Bioactive compounds extracted from plants preserve the biological diversity of predators, reduce environmental pollution and health risks (Jeyapandi and Shunmugavelu, 2020). They exhibit high efficacy against a wide range of pests and diseases, multiple action mechanisms, and low toxicity against non-target organisms (Suteu et al., 2020). Plant extracts elicit antimicrobial effects and act as defence mechanisms against pathogenic microorganisms. The application of plant extracts, especially rich in essential oils, can help in the prevention from post-harvest diseases (Kotzekidou et al., 2008; Koul and Walia, 2009; Gurjar et al., 2012).
Plant extracts as insecticides In 2021, Wilson R. Ravares, Maria do Carmo Barreto and Ana M.L. Seca, all with the Centre for Ecology, Evolution and Environmental Changes (cE3c) / Azorean Biodiversity Group & Faculty of Sciences and Technology, University of Azores, Portugal, conducted a literature review and identified 95 plants whose extracts exhibit insecticide activity and can be used as biopesticides. From their review, they posit that Azadirachta indica, Capsicum annuum, Nicotiana tabacum and Tagetes erecta are the most researched plants and have the potential to be viable options in natural pest management.
The application of plant extracts, especially rich in essential oils, can help in the prevention from post-harvest disease
Godlewska, K., Ronga, D., & Michalak, I. (2021). Plant extracts - importance in sustainable agriculture. Italian Journal of Agronomy, 16(2).
However, deeper cooperation between industrial and academic research is required to accelerate the development of new environmentally safe solutions for future agriculture.
Anecdotal bioinsecticide protection Using natural plant extracts as bioinsecticides isn’t all that new. For example, the ancient Greeks and Romans believed that if seeds were sowed just before a new moon and after being mixed with crushed cypress (Cupressus spp.) leaves, the seeds would be protected from maggots. One of India’s oldest documents describes the use of several plants to protect crops, such as a powdered mixture of the roots of five plants (i.e., Aegle marmelos (L.) Corrêa, Clerodendrum phlomidis L.f., Gmelina arborea Roxb., Stereospermum chelonoides (L.f.) DC. (syn. Stereospermum suaveolens (Roxb.) DC.) and Oroxylum indicum (L.) Kurz) which was used to restore plant health.
Researchers cite the following examples of traditional use of plant extracts as insecticides in some countries. While scientific evidence may be lacking in some cases, the information demonstrates the value of popular knowledge and provides scientists with good starting points in their search for promising sources of new bioactive natural compounds with insecticide properties. • In Ghana, chilli peppers (Capsicum annuum L.) and orange (Citrus sinensis (L.) Osbeck) peel are known for their protection effect of stored crops against insect pests, as well as Azadirachta indica A.Juss., Cymbopogon schoenanthus (L.) Spreng., Securidaca longipedunculata Fresen. And Senna sophera (L.) Roxb. (syn. Cassia sophera L.) [ref 1].
• Local farmers in Kenya use aqueous concoctions of Azadirachta indica and Capsicum annuum for insect pest control [ref 2]. In addition to the aqueous extracts, ashes from cow dung mixed with the pesticidal plants are also used to protect stored crops. • In Malawi and Zambia, rural cultural practices against insect pests involve the use of locally available plants known for their insecticide and repellent properties, such as Azadirachta indica, Bobgunnia madagascariensis (Desv.) J.H.Kirkbr. & Wiersema, Euphorbia tirucalli L., Nicotiana tabacum L., Tithonia diversifolia (Hemsl.) A.Gray, Toona ciliate M.Roem. and Tephrosia vogelii Hook.f., being Tephrosia vogelii the most widely used plant in both regions [ref 3 & 4]. These plants are particularly effective against bollworms and red spider mites affecting tomato crops and against aphids, diamondback moths and webworms affecting cruciferous vegetables crops. In addition, powdered Bobgunnia madagascariensis is popular in Malawi for its molluscicide properties [ref 5]. • In Sri Lanka, Croton laccifer L. branches are detached from the plant and beaten to damage their leaves, originating a strong odour that repels rice bugs present in rice crops. Another technique used to repel these bugs is to burn chipped wood of Cerbera manghas L. near the rice fields [ref 6]. • Some communities in India store their crops in cylindrical basket-like structures made with Borassus flabellifer L. leaves tightly woven to prevent the entry of insects. In addition, leaves of local plants known to have insect deterrent action are used as inner lining of the basket, i.e., Azadirachta indica, Psidium guajava L., Vitex negundo L. and Pongamia pinnata (L.) Pierre [ref 7]. • Indian communities in the south of the country report other pest control techniques, such as the placement of leaves of Azadirachta indica, Coriandrum sativum L., Leucas aspera (Willd.) Link or Pongamia pinnata as layers between the crop sacks stacked one above the other in storehouses. [ref 8]. Acorus calamus L., Azadirachta indica and lime (Citrus spp.) powders can also be used for the same purpose. • Rural farming communities in the Phillippines apply Areca catechu L. fruits and leaves suspended from wooden beams in small storages of rice to repel insect pests [ref 9]. • To control the damage of cotton plantations (Gossypium spp.) by the bollworm (Helicoverpa armigera), farmers in Benin use mixtures of Hyptis suaveolens (L.) Poit., Khaya senegalensis (Desv.) A.Juss. and Azadirachta indica to spray on the cotton plants [ref 10]. • In Cameroon, Cannabis sativa L. is used by farmers of cacao plantations (Theobroma cacao L.) to control cacao pests, particularly capsids insect populations, being planted side-by-side with the cacao plant to act as a deterrent for the pests [ref 11]. Furthermore, the Cannabis sativa aqueous extract is obtained from fresh or dried pounded leaves and is applied alone or in mixture with other local insecticidal plants extracts (i.e., Ceiba pentandra (L.) Gaertn., Erythrophleum ivorense A.Chev., Guibourtia tessmannii (Harms) J.Leonard, Nicotiana tabacum and Pachyelasma tessmannii (Harms) Harms).
• In Uganda, the use of mixtures of various plant parts (bark, flowers, leaves, roots, seeds and stems) from different plant species (Azadirachta indica, Cannabis sativa, Capsicum annuum L. (syn. Capsicum frutescens L.), Cupressus lusitanica Mill., Moringa oleifera Lam., Musa spp., Nicotiana tabacum, Tagetes erecta L., Tagetes minuta L. and Tephrosia vogelii) is common for field and stored crop protections [ref 12]. In this case, the plants alone or mixtures of them are burnt to obtain plant ash that is then applied on the crops to control insect pests such as stem borer (Busseola fusca), banana weevil (Cosmopolites sordidus), bean fly (Ophiomyia phaseoli) grain moth (Sitotroga cerealella), pod borers (Maruca vitrata and Nezara viridula) and aphids (Aphis craccivora, Aphis fabae and Rhopalosiphum maidis). ●
Cannabis sativa is often used as a traditional plant extract to combat pests.
[ref 1]: Belmain S, Stevenson P. Ethnobotanicals in Ghana: reviving and modernising age-old farmer practice. Pesticide outlook. 2001 Jan 1;12(6):233-8. [ref 2]: Deng AL, Ogendo JO, Owuor G, Bett PK, Omolo EO, Mugisha-Kamatenesi M, Mihale JM. Factors determining the use of botanical insect pest control methods by small-holder farmers in the Lake Victoria basin, Kenya. African Journal of Environmental Science and Technology. 2009;3(5):108-15.
[ref 3]: Kamanula J, Sileshi GW, Belmain SR, Sola P, Mvumi BM, Nyirenda GK, Nyirenda SP, Stevenson PC. Farmers' insect pest management practices and pesticidal plant use in the protection of stored maize and beans in Southern Africa. International Journal of Pest Management. 2010 Oct 29;57(1):41-9. [ref 4]: Nyirenda SP, Sileshi GW, Belmain SR, Kamanula JF, Mvumi BM, Sola P, Nyirenda GK, Stevenson PC. Farmers’ ethno-ecological knowledge of vegetable pests and pesticidal plant use in Malawi and Zambia. African Journal of Agricultural Research. 2011 Mar 18;6(6):1525-37.
References
[ref 5]: Thokozani BL, Zulu D, Sileshi CW, Teklehaimanot Z, Gondwe DS, Sarasan V, Stevenson P. Seed germination and in vitro regeneration of the African medicinal and pesticidal plant, Bobgunnia madagascariensis. African Journal of Biotechnology. 2011;10(32):5959-66.
[ref 6]: Widanapathirana CU, Dassanayake AL. The use of plant parts in pest control activities in traditional Sri Lankan agricultural systems. Int J Sci Technol Res. 2013;2(6):150-2.
[ref 7]: Kiruba S, Sam Manohar Das S, Papadopoulou S. Prospects of traditional seed storage strategies against insect infestation adopted by two ethnic communities of Tamil Nadu, southern peninsular India. Bulletin of Insectology. 2006;59(2):129.
[ref 8]: Karthikeyan C, Veeraragavathatham D, Karpagam D, Firdouse SA. Traditional storage practices.
[ref 9]: Zapico FL, Aguilar CH, Abistano A, Turner JC, Reyes LJ. Biocultural diversity of Sarangani Province, Philippines: An ethno-ecological analysis. Rice Science. 2015 May 1;22(3):138-46.
[ref 10]: Sinzogan AA, Kossou DK, Atachi P, Van Huis A. Participatory evaluation of synthetic and botanical pesticide mixtures for cotton bollworm control. International Journal of Tropical Insect Science. 2006 Dec;26(4):246-55.
[ref 11]: Coulibaly O, Mbila D, Sonwa DJ, Adesina A, Bakala J. Responding to economic crisis in sub-Saharan Africa: New farmer-developed pest management strategies in cocoa-based plantations in Southern Cameroon. Integrated Pest Management Reviews. 2002 Sep;7(3):165-72.
[ref 12]: Mugisha-Kamatenesi M, Deng AL, Ogendo JO, Omolo EO, Mihale MJ, Otim M, Buyungo JP, Bett PK. Indigenous knowledge of field insect pests and their management around Lake Victoria basin in Uganda. African Journal of Environmental Science and Technology. 2008;2(10):342-8.
References continued
This Series A round of funding will support the production and sales growth of BSI’s first commercially successful product marketed as BotriStop and its recently announced global brand Quillibrium, which are based on an extract from a plant native to Chile, the Quillaja Saponaria Molina. BSI states Quillibrium has been used successfully on a wide variety of fruits and vegetables throughout Chile.
Quillibrium was launched in Peru last year and will soon reach growers across Mexico through BSI’s main distribution partner Syngenta. Meanwhile, the product continues to go through the regulatory progress in the U.S. and will soon initiate registration in additional countries.
This new funding will also accelerate market readiness of new botanical biopesticide products currently in later development stages and enable the expansion of BSI’s R&D pipeline.
Two long-time investors joining Otter Capital in this First Closing of the Series A are Inversiones el Coigue and Inversiones Eurocel, both based in Santiago, Chile.
Read about BSI’s expansion plans in New AG International here. ●
Canada-based MustGrow Biologics Corp. and Bayer have signed an exclusive agreement to evaluate MustGrow’s biological technologies to determine efficacy and commercial potential in key agricultural regions.
MustGrow has granted Bayer the right to use MustGrow’s intellectual property for testing purposes and the option to acquire exclusive rights to MustGrow’s extract technologies for preplant soil fumigation, bioherbicide applications, and postharvest food preservation of potatoes, including sprout inhibition in the regions of Europe, Asia Pacific, Middle East and Africa.
Under the agreement, Bayer will fund and drive all laboratory, field development, regulatory work and market development necessary for commercialization. MustGrow continues to conduct field trials, R&D and regulatory development concurrently in other regions, collaborating with numerous agriculture, chemical products, and consumer food companies.
MustGrow has designed and owns a U.S. EPA-approved natural solution that uses the mustard seed’s natural defence mechanism to protect crops from diseases, pests and weeds. ●
Since its inception 20 years ago, ORO AGRI has been developing and manufacturing unique patented formulations based on plant extracts, with low environmental impact for the agricultural, industrial, ornamental, and home & garden markets. Our investment in research and development combines science with natural and renewable resources to create products that are safe and sustainable, using the best of what Nature has to offer to protect agricultural production and help feed the world.
Agriculture has always been demanding, but nowadays, growers face a multitude of new factors that directly impact their activities and forces them to constantly adapt to meet these new challenges. That is why a new era for nature-based, low-environmental impact products, with innovative modes of action, is upon us. Our range of products contains multiple plant extract ingredients that are mostly by-products of the food and beverage industry and are repurposed to effective tools to be
From the Peel to the Field: Everything starts in the field with oranges being harvested. The orange peels, a by-product of orange juice production, are cold-pressed and our proprietary botanical compounds are extracted. Combining our science with the best of what Nature offers, we then create products that will be used in fields to grow more oranges and other crops. It is, therefore, a sustainable and environmentally friendly cycle of protection.
used in farmer fields. We have built a portfolio of products from soil conditioners, drift reduction agents, fertilisers, biocides, to adjuvants and biopesticides, that provide valuable inputs for farmers adept at adopting and adapting best practices to become more efficient and sustainable. Growers rely on new products from crop protection manufacturers to meet their goals of increasing yields while producing healthy food with little or no pesticide residues, all while keeping farmworker and environmental safety as a top priority. Our proprietary OROWET® and ORONEO® technologies utilize a unique blend of botanical oils, proprietary surfactants and other key ingredients. Our plant-based solvents are cold-pressed and extracted from a by-product of the agricultural industry and are, therefore, a completely renewable
and natural resource. This extraction method provides highly stable solvents that are safer for the farmer, plants and the environment. These adjuvant product formulations are compatible with a wide variety of organic and conventional pesticides, nutrients, and other crop protection tank-mix partners. In addition, our OROWET technology uses orange oil, sourced from the citrus industry, as its primary plant extract because it provides a wide array of concentration-dependent applications for our biopesticides.
PREV-AM® (also sold under brands OROGANIC®, PREV-GOLD®, OROCIDE®) is a multipurpose biopesticide containing OROWET technology, that utilises a proprietary blend of botanical compounds found in cold-pressed orange oil. It is a contact pesticide solution against various insects, diseases, and mites. An application of PREV-AM protects against these three pest threats simultaneously, which is a unique characteristic among other pesticides on the market. PREV-AM provides broad-spectrum protection in open field and greenhouse conditions for organic and conventional farming operations. It helps meet growers' goals with an effective biopesticide exempt from MRL tolerances, significantly reduced worker and environmental safety concerns, and minimal impact on beneficial fauna compared to conventional chemical pesticides. The continuous quest of ORO AGRI for scientific knowledge drives us to invest heavily in plant science and plant protection research. This research has shown the greatest value of PREV-AM, while highly effective as a stand-alone application, is optimised when its quick knockdown, physical mode of action and reduced chance of resistance is used in synergy with other active ingredients and/or biological controls. It also has been proven that using PREV-AM as part of a regular spray program provides great economic return by knocking down pests' populations before they reach the damage threshold that might require more expensive and resistance-susceptible pesticide applications.
Our products being applied in an orange field.
To complement our bioprotection portfolio ORO AGRI also provides solutions in almost all crop input categories needed by farmers. Combining multiple technologies, such as TransPhloem™ technology and ORONEO® technology, our multipurpose adjuvants provide superior spreading, wetting and penetrating properties, enhancing rainfastness due to superior cuticle penetration and improving movement through epicuticular wax. This versatile range of functions allows our adjuvants to be used with excellent efficiency in combination with multiple types of agrochemicals. Our soil conditioner products aim to improve the infiltration, distribution and drainage of irrigation water and rain into the soil. Our patented formulations overcome differences in soil density, and even hydrophobic soil, to move the spray solution throughout the soil profile. By promoting uniform distribution and spreading of pesticides throughout the soil, we dramatically improve the effectiveness of irrigation and soil treatments while mitigating water shortages and extreme drought events. Using first-class raw materials produced and extracted from premium locations throughout the world, combined with our technology that includes plant extracts, our fertiliser range is an effective tool against nutrient deficiency. It provides an immediate solution to the nutrient shortage, preserving plant health and yield. Also obtained from plant extracts, our newest products in the portfolio include a drift reduction agent, able to minimise the spray drift of targeted pesticide applications. This can diminish contamination of an adjacent land area, public locations and natural watercourses and streams and avert pesticide hazards to human health and the environment. ORO AGRI is present in more than 90 countries, having factories in 4
Our R&D focus in environmental friendly solutions based in plant extracts.
different continents and state of the art science and research centres in Brazil, Europe, the U.S., and South Africa. Our research database contains more than 2000 field trial studies, including contributions from over 500 universities and research consulting groups. This research has led to over 200 patent applications, 22 patents, 182 product registration certificates, more than 100 pending registration certificates, and over 1500 granted applications for various trademarks and slogans. Farmers will continue to face agronomic, societal, and environmental pressures as they strive to produce a healthy food supply. But with ORO AGRI products they have important tools to address many of the most pressing issues, such as water scarcity, resistance management, pesticide residues, and food safety and sustainability.●
All brands and trademarks mentioned are proprietary of Oro Agri International Ltd.
www.oroagri.eu info-eu@oroagri.rovensa.com Source: ORO AGRI EU Marketing Department
By Dr. Herbert Welte, lead of marketing specialty crops and Mathilde Roger, project manager specialty crops, Certis Europe
Pioneering work to reduce copper usage is critical for the future of organic vine production. Producers remain under pressure to use less copper but, with few real and effective alternatives available, are dependent on the active ingredient for downy mildew control.
Copper has been used successfully as a broad-spectrum fungicide for over a century. Though it is accepted in organic production there have been continuing demands over the years to reduce its use due to environmental concerns. This has led to an evolution of the existing formulations, which have resulted in improvements in efficiency and plant safety. New copper products are still being developed today and significant strides have been made in terms of lower dose rates, thus reducing environmental impact whilst still providing superior disease control in a wide variety of crops.
In response to the rapid and continuing evolution of organic production of vines in Europe (around 350,000 hectares in 2019, representing over 11 percent of the EU vineyard and still increasing; source: Eurostat/Agence Bio), there has been a clear need to develop appropriate crop protection solutions for this sector, which enjoys few alternative options for effective control of downy mildew (Plasmopara viticola).
As a leading player in the copper market Certis Europe is determined to promote responsible use of the active ingredient. In 2019, a limitation of 28 kilograms of copper per hectare over a period of seven years was imposed across European countries. In some situations it was challenging to achieve control at these levels. All copper active ingredients were reviewed at EU level and products containing copper compounds are currently under
New copper products are still being developed today and significant strides have been made in terms of lower dose rates
evaluation at country level. The results of these reviews could lead to greater limitations. In anticipation of that, Certis teams have directed their own innovative efforts to optimize copper usage for organic viticulturists.
Since 2016, trials have been ongoing in Germany and Austria with a target of reducing total copper usage for fungicide control in grapes substantially, e.g., to one kilogram of metal copper per hectare per year total, whilst maintaining efficacy and efficiency. The trials have shown that by using a combination of Cuprozin Progress (a copper hydroxide formulation) with Kumar (a biorational product also registered as Armicarb and Karma) (European patent granted), successful control can be achieved using a substantially reduced rate of copper. The rate required depends on the crop stage and disease pressure on the vines and growers are used to modulating levels applied accordingly. The trials show that even at lower dose copper, the synergistic effect of the two products increases efficacy.
In France, the team has been looking in particular at determining the correct dose rate depending on the vegetation height and sensitivity of the vines through the season. Growers have always modulated in the field with rough calculations on the dose to be used (within the whole season limitation) but Certis wanted to make this approach more scientific.
Early-stage work was based on the calculated leaf area of the vines giving a dose per 10,000 square metres of leaf wall area. In the second year of trials, disease pressure and external conditions were incorporated to the model to
add timings and frequency of application to dose rates, still within the total constraint on copper use. The model now factors in rain, temperature and humidity to place the product correctly before contamination occurs, sensitivity of the growth stage as well as the leaf area calculation. Indeed, at certain stages the vine is less sensitive to downy mildew attack. For example, in early stages the risk is low, but this increases at flowering, so a high dose is recommended around the time of flowering. Later, when the grapes are ripening, the bunches are no longer sensitive; and when the shoots are pruned there is no new vegetation, and what is there has already been treated and is therefore low risk, needing only a low-rate application. The results have been good, and this is a leading approach.
After three years, trials results are encouraging and showing the maintenance of disease control with reduced levels of copper usage. Further trials are being undertaken to refine the correct copper dose to apply, defining two dose rates: one for high-risk periods, one for low-risk periods. The possibility of further reducing the copper rate by adding a partner product was investigated and the result validated with one of the biocontrol products tested in 2020.
A further consideration is also being trialed in France, the quality of application via a simple marker: the water volume used. The quality of the application can be critical, especially as both upper and lower surfaces of the leaves need to be covered by the spray application. Doubling the water rate showed encouraging results with improved efficacy. Trialists were asked to test the application quality using hydro-sensitive papers, and all aspects such as nozzles, pressure and the machine itself are under consideration.
Downy mildew (Plasmopara viticola) seen on the vine
The trial demonstrated that the points of efficacy gained are interesting, especially on disease incidence on bunches (+13 percent efficacy), and results are more homogeneous, only by using a double water volume. This highlights the fact that quality of application will be an essential tool to further optimize copper use.
In Italy too over the last few years, the company has been working on developments to support organic growers in the sector. In cooperation with several leading organic viticulturists, the team has developed a customized organic defence strategy adapted to the needs of each individual farm. The program, launched as ViteBio, offers complete and effective protection for the vines throughout the season, customized not only in terms of products used, but also in terms of the technical support provided by technicians in the field.
Crop pathogen monitoring systems are fundamental to the overall strategy, to inform the grower of the requirement and timing for disease control applications. Application technique and timing is of course critical for the products used, and the formulated copper hydroxide product included in the program provides an excellent foundation for disease control when applied as a protectant. Use of the ViteBio defence strategies has spread to leading wineries across Italy and further developments are ongoing.
New regulations could undoubtedly have some impact on organic production of vines in the EU. The work undertaken to date and in the future by Certis Europe will continue to support viticulturists in their quest for efficacious disease control and quality production whilst respecting the legislative and environmental requirements imposed on them. ●
A UK-Kenya collaboration has targeted one of the most economically important crop pests – potato cyst nematode (PCN) – through the development of a new assessment tool.
The tool aims to enable farmers in Kenya to successfully detect PCN in-field, supporting informed decision making for both cropping choices, and the use of control measures.
Developed over the course of 21 months, it is the output of a collaboration between UK Agri-Tech Centre Crop Health and Protection (CHAP), PES Technologies, and the International Centre of Insect Physiology and Ecology (icipe).
According to Dr Jenna Ross, international business development manager for CHAP and nematologist, potatoes are an important crop in Kenya, with around 800,000 people benefiting directly from their production.
“Although PCN is a relatively new pest in the region, first detected in 2015, a recent survey showed that it is widespread in the main potato growing areas,” said Ross. “Because of this threat, potato farmers urgently needed a better diagnostic tool to detect the pest, which is what initiated the collaboration.”
PCN (Globodera rostochiensis and Globodera pallida) are microscopic pests. The ‘cyst’ contains hundreds of eggs that, once triggered, hatch into larvae that attack the plant’s roots, causing up to 80 percent yield loss.
To initiate the project, data was gathered on the distribution and species composition of PCN in two key potato growing areas – Nyandarua and Meru. This included taking soil samples for analysis from more than 210 farms, with significant infestation identified.
These samples were then used to evaluate a new innovation from PES Technologies, a novel on-farm tool that provides soil health analyses. This hand-held technology analyses microbial activities in soil, linking in-depth soil health information to mobile devices such as smartphones and laptops.
“We are developing this solution to provide more soil health indicators from a soil sample than any other tool in the world,” said Andrej Porovic, CEO of PES Technologies. “Because it’s hand-held, farmers can take samples themselves and the whole process from sampling to results only takes five minutes.
“Through this project, we’ve been able to adapt and trial the system for identification of PCN and are now conducting further analysis of sensor data,” added Porovic. “We look forward to developing it further with the aim of eventually providing Kenyan farmers with a quick, easy and cost effective PCN assessment method.”
During soil sample collection, all farmers visited in Nyandarua and Meru were interviewed on cropping practices and knowledge of PCN. This showed that significantly more farmers in Nyandarua (60 percent) were aware of PCN compared to Meru (five percent). It also showed there are more female-owned farms in Nyandarua compared to Meru.
As a result, a series of 15 stakeholder workshops and training events were hosted, to help address gender equality issues and equip farmers with valuable knowledge.
“This project has helped inform our knowledge of PCN distribution in Kenya, as well as testing a novel PCN assessment tool which we hope will succeed,” said Dr Solveig Haukeland, nematologist at icipe. “It is hoped that it will also address associated challenges, such as access to clean seed, optimizing crop rotations and maximizing soil health, as well as food security and income.”
The work was funded by Innovate UK’s Agri-Tech Catalyst Round 8: Agriculture and Food Systems Innovation call, supported by the former Department for International Development (DFID) and Global Challenges Research Fund (GCRF). ●
A new study led by CABI scientists has confirmed that a tiny mite, Aculus crassulae, shows promise to be used as a more environmentally friendly biological control agent against the aquatic weed Crassula helmsii in the UK and Europe.
The research, published in the journal Biological Control, reveals that A. crassulae favors C. helmsii – otherwise known as Australian swamp stonecrop or New Zealand pigmyweed.
Aculus crassulae on Crassula bud. Photo: CABI
C. helmsii is an invasive semi-aquatic, succulent, perennial herb that occurs in three growth forms – terrestrial, emergent and submerged – with the growth form exhibited dependent on the depth of the water in which the plant is found. It is capable of causing fluctuations in dissolved oxygen, carbon dioxide and nutrient levels in infested water bodies which can have wide-ranging impacts on aquatic species.
Dr. Sonal Varia, lead researcher, said the reduction in overall vegetative growth – particularly in primary stem and secondary shoot growth – in plants colonized by mites under laboratory conditions suggests that A. crassulae could have a significant impact on the growth of C. helmsii field populations by reducing the number of vegetative propagules available to spread to new uninvaded sites.
It is believed the aquatic plant was first imported into the UK from Australia sometime before 1914 and later sold as an oxygenating plant for aquaria and ponds. It was subsequently found growing in the wild in Essex, southeast England in 1956, later spreading throughout the UK where it is now naturalized, and also in parts of northwest Europe, particularly in lowland regions. ●
An innovative method of controlling a range of damaging crop diseases using native, beneficial soil bacteria has emerged from a research-industry collaboration.
A team at the UK-based John Innes Centre isolated and tested hundreds of strains of Pseudomonas bacteria from the soil of a commercial potato field, and then sequenced the genomes of 69 of these strains. By comparing the genomes of those strains shown to suppress pathogen activity with those that did not, the team was able to identify a key mechanism in some of the strains that protected the potato crop from harmful disease-causing bacteria. Using a combination of chemistry, genetics and plant infection experiments, they showed that the production of small molecules called cyclic lipopeptides is important to the control of potato scab, a bacterial disease that causes major losses to potato harvests.
These small molecules have an antibacterial effect on the pathogenic bacteria that cause potato scab, and they help the protective Pseudomonas move around and colonize the plant roots. The experiments also showed that irrigation causes substantial changes to the genetically diverse Pseudomonas population in the soil.
“By identifying and validating mechanisms of potato pathogen suppression, we hope that our study will accelerate the development of biological control agents to reduce the application of chemical treatments which are ecologically damaging,” said first author of the study Dr. Alba Pacheco-Moreno. “The approach we describe should be applicable to a wide range of plant diseases because it is based on understanding the mechanisms of action that are important for biological control agents.”
The study, which appears in eLife, proposes a method by which researchers can screen the microbiome of virtually any crop site, and take into account varying soil, agronomic and environmental conditions. By exploiting advances in high-speed genetic sequencing, the method can screen the soil microbiome for therapeutic bacteria and work out which molecules are being produced to suppress pathogenic bacteria. They can also show how these beneficial bugs are
affected by agronomic factors such as soil type and irrigation.
The next step for the new approach is to put the beneficial bugs back into the same field in greater numbers or in cocktails of mixed strains as a soil microbiome boosting treatment.
“The massive advantage of this approach is that we are using bacterial strains that are taken from the environment and put back in the same specific biological context in larger numbers so there is no ecological damage,” noted Dr. Jacob Malone, group leader at the John Innes Centre and co-corresponding author of the study.
Potential methods to apply the microbiome boosters include applying the bacterial cocktails as seed coatings, as a spray or via drip irrigation.
“In the future, it’s not the molecule produced by the bacteria that we would use, it would be the Pseudomonas strain itself,” said Dr. Andrew Truman, group leader at the John Innes Centre and corresponding author of the study. “It offers a more sustainable route – we know these bacteria colonize the soil where potatoes grow, and they provide protection to the crop. Using a bacterium, you can easily grow and formulate it in an appropriate way and apply it to the field, and it is much greener than using a synthetic chemical.” ●
Researchers say “smart soil bugs” could help prevent diseases in potatoes. Photo: Janet Kanters
The Bodles Research Station in St. Catherine (Jamaica) now boasts a new biological control laboratory, which will strengthen the island’s pest control measures while helping to protect the environment.
According to Michelle Sherwood, acting principal research director for the research and development division in Jamaica’s Ministry of Agriculture and Fisheries, the lab will focus on the use of biological control agents to kill pests that can harm plants.
“We are familiar with the farmer’s friend like the wasp, the ladybird beetle and other insects. With this lab, we’re now able to harness from our natural environment, those biocontrol agents, which we now can collect for research,” said Sherwood. “We now have an environment to be able to multiply and release them as an additional tool to the farmers.”
Meanwhile, a greenhouse was also built at Bodles to produce citrus fruit seedlings under the Clean Seed Development Programme. The programme operates under the 2019 National Seed Policy, which aims to increase the island’s ability to produce all the planting material needed for the entire agriculture sector.
The vision of the policy is to establish a sustainable seed system that ensures a consistent and reliable supply of clean, affordable, and accessible seeds, in support of agricultural production, productivity, food security and biodiversity.
“With this new facility we are now able to produce clean seeds for the citrus industry, which has been negatively impacted by citrus greening disease,” Sherwood noted. “This helps us to supply our nurseries through the citrus unit out of the plant quarantine facility. We have a project with the Rural Agricultural Development Authority (RADA) where we are producing limes and lemons.” ●
A team of Agricultural Research Service (ARS, U.S.) and university scientists has developed an electronic nose to sniff out whitefly infestations of tomato plants.
The "E-Nose" works by detecting a specific cocktail of chemicals, called volatile organic compounds (VOCs), that tomato plants release into the air when attacked by whiteflies. In nature, these chemicals put other plants on high alert. Scientists are hoping the E-nose will also warn growers so they can fine-tune their use of whitefly-killing insecticides, biocontrol agents like parasitic wasps or other measures.
According to Heping Zhu, an agricultural engineer with the ARS Application Technology Research Unit in Wooster, Ohio, who co-developed the E-nose with collaborators at The Ohio State and University of Tennessee-Knoxville, whiteflies are top insect pests of U.S. fresh-market tomatoes, which were valued at USD$721 million in 2020.
Whitefly monitoring typically involves checking for a threshold number of the pests per leaf on a sampling of plants or captured in sticky traps—both a time-consuming process. But, scientists wondered, what if the plants could alert the growers themselves—and in real-time?
The researchers designed a prototype E-nose device about the size of a shoebox that can operate in the greenhouse. According to Zhu, the device mimics the mammalian sense of smell and brain's ability to recognize certain odours. The E-nose uses gas sensors, data acquisition modules and other components to “smell.”
A key feature of the E-nose is a nerve-like circuitry board that helps convert VOC samples from the air into digital signals. These signals in turn are transmitted to the system's "brain," namely, a mathematical algorithm programmed to recognize specific types and concentrations – d "smell-fingerprints" – of VOCs that tomato plants give off when attacked.
In greenhouse tests, the E-nose displayed the VOC fingerprints of such plants as different lines with different colours that rose sharply and steadily to the right of an LED screen. Moreover, the system distinguished the smell-fingerprints of whitefly-infested tomato plants from un-infested ones, as well as plants whose leaves were punctured with pins for comparison.
With additional testing and development, the E-nose could give greenhouse growers another monitoring tool to use in deciding where, when and how best to tamp down whitefly infestations before they reach economically damaging levels. Besides whiteflies, the E-nose also successfully sniffed out tomato-infesting aphids and insect pests of other greenhouse crops.
"The future E-nose system can be designed as a hand-held device for growers to take samples from individual plants," Zhu said. "It can also be designed as a computer-controlled cloud networking system which consists of multiple smart sensors placed at different locations in the greenhouse, so the computer can automatically collect samples and monitor infestations 24 hours a day." ●
An electronic nose that sniffs out whitefly-infested tomato plants could help greenhouse growers time their use of pest controls.
Graphic: Heping Zhu, ARS, and Shaoqing Cui, Ohio State University
Plant Response, an industry consolidator of biological-based solutions, recovered waste fertilizers and other crop input technologies, has been acquired by The Mosaic Company, a global manufacturer of agricultural fertilizers and chemicals. Cascadia Capital, an investment bank serving the agtech sector, acted as the exclusive financial advisor to Plant Response.
Plant Response brings together a portfolio of biological-based crop inputs and technologies, having recently consolidated Koch Biological Solutions (2019), Pathway BioLogic (2020), and WISErg (2021). With 16 commercialized products, Plant Response aims to enhance grower returns by improving nutrient use and efficiency, improve disease defense, biocontrol, tolerance to abiotic stress and increase overall crop yields.
Together, Mosaic and Plant Response will develop new soil health solutions that will provide advanced crop nutrition to customers around the globe and help the world grow the food it needs
Plant Response was backed by leading food and agriculture investors and strategics, including Alexandria Venture Investments, Koch Agronomic Holdings, Laird Norton Company, iSelect Fund, Second Avenue Partners, Middleland Capital, Yara, Novozymes, and Leaps by Bayer, among others.
The Mosaic Company is a Fortune 500 company based in Tampa, Florida and the largest U.S. producer of potash and phosphate fertilizer. The company employs more than 13,000 people in six countries to serve farmers all over the world.
A statement from The Mosaic Company: “We’re excited that Plant Response has joined The Mosaic Company. Their ability to innovate sustainable soil health solutions will complement our market access in key agricultural geographies, agronomic expertise, and reputation for selling products that are backed by science. Together, Mosaic and Plant Response will develop new soil health solutions that will provide advanced crop nutrition to customers around the globe and help the world grow the food it needs.”
Plant Response represents Mosaic’s first acquisition in over five years, beginning a reprioritization of the company’s M&A strategy. ●
Dr. Herbert Welte and Mathilde Roger