What is a Biostimulant?A substance or micro-organism that, when applied to seeds, plants, or on the rhizosphere stimulates natural processes to:Enhance nutrient uptakeBetter nutrient use efficiencyEnhance tolerance to abiotic stress, crop quality and yield The purpose of Biostimulants is to stimulate plant growth and optimize plant health.Key stresses that Biostimulants addressClimatic stresses (Drought, Heat and Cold Stress) refer to an external stress upon a crop originating from a prolonged environmental condition outside of a reasonable normal.Successful Biostimulants will expand the adaptable range of a crop measured through yield quantity and quality.Soil health / Salinity refers to the maintenance and enrichment of soil to prevent and reverse soil degradation.Successful Biostimulants will increase the potential of soils to sustain growing crops through directly targeting soil environments.Crop quality refers to increasing a measurable aspect of crop growth or production resulting in an increased…

A relatively new type of plant health product which complements both crop protection and nutrition, biostimulants are set to play an increasing role in integrated pest and disease management programmes for ornamentals.Because they have no direct effect on pests or diseases they fall outside the scope of plant protection legislation, but you still need to take care to source products from manufacturers who can provide the research and trials evidence to back their claims. Biostimulants can include various substances, sometimes micro-organisms, that can boost plant vigour, yields, quality or stress tolerance. Many include nutrient compounds: though these act through different mechanisms to fertilisers, biostimulants have recently been brought into Europe-wide regulations covering the performance and quality of fertilisers and related products, which should help to raise product quality overall and give growers more confidence to use them. You may have already tried one or two of these products but…

Last time we focused on why biopesticides and biostimulants are featuring more in growers’ IPM programmes. This time we’ll look in more detail at biopesticides and how to get the best from them.Remember, a biopesticide has to be authorised as a plant protection product and carry a unique product registration number known as the MAPP (which stands for Ministerially Approved Pesticide Product) number. Essentially there are three kinds of biopesticide:Microbial: The active substance is a micro-organism, or in some cases a compound produced by a fungus or bacterium. Fungi that parasitise insect pests, bacteria that infect plant pathogens, and the viruses used to control moth pests in orchards are examples.Botanical: These active substances are plant extracts or their individual compounds, some plant species being particularly rich in defence chemistry. Examples include a bioinsecticide compound extracted from neem seeds, garlic-based products for nematode control and some fatty-acid-based biopesticides…

Integrated Pest Management Programmes (IPM) require the use of a wide variety of methods in the judicious management of crop pests. Among the key approaches of IPM, chemical and biological control strategies are harnessed. There are various natural enemies used in biological control of pests in crops and these include but not limited to;Phytoseiulus persimilisAmblyseius cucumerisAmblyseius californicusAmblyseius montdonrensisAmbylseius swirskiiAmblyseius andersoni However, applicability of these natural enemies in IPM programmes requires beforehand information on compatibility of commercial pesticides with the beneficial organisms. Therefore, information on WHO class, active ingredient, mode of action and toxicity level of the pesticide on natural enemies is important.This is generated by conducting compatibility studies of pesticides with natural enemies to determine the effect on mortality and if the product can be applied alongside the natural enemies in Integrated Pest Management.Compatibility…

There comes a point when an emerging technology moves from the ‘alternative’ to the mainstream – no longer in the hands of small manufacturers and a few early adopters but embraced by companies with the ability to develop it to a point where it’s reliable and trusted enough, and easy enough to use, for just about everyone.That’s pretty much the situation today with biopesticides, and to a similar extent with biostimulants. The two are often mentioned in the same breath but are in fact quite different types of product with quite different uses, as we’ll discuss later. Some would say biopesticide technology has been a long time emerging. Insecticides based on the insect-killing fungus Verticillium lecanii (now known as Lecanicillium muscarium) have been around for decades. So what’s changed? Why are we now seeing more biopesticides on the market; why are they now regarded as key elements of integrated pest and disease control programmes in their own right; and why are companies like…

Nematodes are microscopic, eel-like roundworms. The most troublesome species are those that live and feed within plant roots and those living freely in the soil and feed on plant roots. There are many different species of root-feeding nematodes, the most damaging are the rootknot nematode, Meloidogyne spp. Root knot nematodes attack a wide range of plants, including many common vegetables, fruit trees, and ornamentals. Symptoms & Life CyclePlants with root-knot nematode infections show poor growth; they are stunted with yellowing leaves, and wilt easily. Root systems show characteristic knots or galls, which prevent the uptake of water and nutrients. Plants with root-knot nematodes are more susceptible to invasion by disease-causing fungi and bacteria. A microscope is needed to see root-knot nematodes; the active stage, the "juveniles", are about 0.5 mm long, and they are too small to be seen by the naked eye. The eggs are laid outside the root, and hatch to release the juveniles,…

Following on from our successful webinar on Nematode Management Webinar, as promised you can now re-watch all of our speakers and their presentations to further your knowledge.We have Professor Danny Coyne who details all the different types of plant parasitic nematodes, Dr Solveig Haukeland discusses the different types and how best to manage them.Daisy Ngeno, our Technical Manager delves into greater detail around the important topic of resistance management and the practices you can follow and finally Dr Kanan Saikai discusses non-parasitic nematodes and their lifecycles.By watching these videos, you will gain a thorough understanding of improving nematode management in your crops to improve yield and crop quality.Visit our YouTube channel for more free horticulture videos from our experts. 

False codling moth also known as Thaumatotibia leucotreta is a native pest to sub-Saharan Africa and is present on more than 70 host plants crops like roses, citrus, peppers (Capsicum spp.), maize etc. making it a challenge to control it. It also occurs on some of the Indian and Atlantic Ocean islands, such as Mauritius and Cape Verde. False codling moth was previously known as Cryptophlebia leucotreta. FCM is an economically important pest for roses as it causes crop damage and is categorized as a quarantine pest by the European Union (EU).     Economic impact of FCM interceptionsAlready several rose growers have incurred financial losses due interceptions in the EU of their produce. These interceptions have led to an increase in checks from 5% to 10% on import inspections into the EU. These checks affect all Kenyan rose exporters. An integrated approach by the floriculture sector in dealing with the challenge of FCM is therefore crucial.     External frass is a sign…

Thrips, order Thysanoptera, are tiny, slender insects with fringed wings. They feed by puncturing the epidermal (outer) layer of host tissue and sucking out the cell contents, which results in stippling, discolored flecking, or silvering of the leaf surface.Thrips feeding is usually accompanied by black varnishlike flecks of frass (excrement). Pest species are plant feeders that discolor and scar leaf, flower, and fruit surfaces, and distort plant parts or vector plant pathogens. Many species of thrips feed on fungal spores and pollen and are often innocuous. However, pollen feeding on plants such as orchids and African violets can leave unsightly pollen deposits and may reduce flower longevity. Certain thrips are beneficial predators that feed on other insects and mites. Thrips can readily move long distances floating with the wind or transported on infested plants, and exotic species are periodically introduced. IdentificationMost adult thrips are elongate, slender, minute (less than 1/20 inch…

Biology of the pestsAdult leaf miners are small (1.8 mm), yellow and black flies that are about the same size and shape as fruit flies. In contrast to shore flies, leaf miner adults are brightly colored and have clear wings. they are often found on yellow flowers or objects. Females insert their eggs within leaves and also puncture the leaf surface with the ovipositor to feed on damaged plant tissue. Larvae have three instars, forming larger mines inside the leaves as they grow. Liriomyza trifolii mines are readily observed from the top of the leaf, while Liriomyza huidobrensis mines may only be visible from the underside of the leaf. Liriomyza huidobrensis mines tend to follow the veining pattern of the leaf. after completing their feeding, larvae drop from leaves to pupate in the soil. Liriomyza trifolii can complete one generation in 14 days at 95°F 64 days at 59°F.DamageWhen populations are high, stippling, caused by females puncturing the leaves with their…

Fungal leaf spots are the most common and obvious diseases present during ornamental crop production. In most cases, they are easily noticed, and the temptation to guess specific causes is great. While certain characteristics may often be present with each type of leaf spot disease, there are no hard and fast rules about diagnosing by the "seat of your pants." Most serious diagnosticians recognize the need to culture the pathogen before making a recommendation for the best treatment.Pathogens such as Alternaria and Colletotrichum (anthracnose) affect most ornamentals, including bedding plants, cut flowers, and cut foliage, tropical foliage plants and woody crops. Other diseases such as Fusarium leaf spot on dracaenas and fairy ring leaf spot on dianthus affect a narrow range of ornamentals but remain serious concerns for producers of those crops. Fungal leaf spots rarely kill a crop, but on rooted cuttings, such as pittosporum, Alternaria can result in massive losses. It is also possible to incur huge losses…

Powdery mildews are among of the most common diseases of ornamentals; many flowers, vegetables, and woody plants are susceptible. Greenhouse crops prone to infection include Roses, African violet, Begonia , Dahlia , gerbera daisy, Hydrangea , roses, Verbena, Kalanchoe, and Poinsettia. Herbaceous perennials particularly susceptible to powdery mildew include Aster, Centaurea, Coreopsis, Delphinium, Monarda, Phlox, Rudebeckia, and Sedum. SymptomsThe disease is easily recognizable as a white to gray powdery growth on leaves and sometimes stems and flowers. It is usually most severe on the tops of leaves but can appear on the undersides as well. Mild cases of powdery mildew may have little or no effect on the plant other than diminishing its aesthetic value; on other instances, infected leaves may become distorted, discolored, and die prematurely. In general, powdery mildews have evolved to avoid killing their hosts because they need living plant tissue to…