Aphids

Aphids, a diverse group of small insects, have a notable impact on cucumber crops, with various species like Cotton aphid (Aphis gossypii), Glasshouse potato aphid (Aulacorthum solani), Potato aphid (Macrosiphum euphorbiae), and Green peach aphid or Tobacco aphid (Myzus persicae) posing significant challenges. These tiny pests feed on cucumber plants by piercing their tissues and extracting sap, leading to reduced plant vigor and potential yield loss. These aphids can not only stunt plant growth but also transmit various plant viruses, compounding the threat to cucumber crops.

Leaf miners

Leaf miners pose a persistent challenge within cucumber crops, with species like Tomato leafminer (Liriomyza bryoniae). These pests exhibit a unique and damaging behaviour, as their larvae burrow into cucumber leaves, creating distinctive serpentine tunnels as they feed on the plant's internal tissues. Leaf miners can rapidly infest cucumber plants, leading to reduced photosynthetic activity and compromised foliage integrity.

Mealybugs

Mealybugs can be a challenge for cucumber crops, with species like Citrus mealybug (Planococcus citri) being particularly troublesome. These tiny insects, characterized by their waxy and mealy appearance, have the potential to cause significant damage to cucumber plants. The citrus mealybug is one of the species that can infest cucumber foliage and stems.

Moths & Caterpillars

Moths and caterpillars are a significant threat to cucumber crops, with species like the tomato looper (Chrysodeixis chalcites) standing out as a noteworthy pest. The larvae of various moth species, can rapidly multiply and inflict substantial damage to cucumber plants. Feeding voraciously on cucumber foliage, these caterpillars can defoliate plants and impair fruit development, ultimately leading to reduced yields.

Plant bugs

Cucumber crops can also suffer from the presence of other plant bugs that can have adverse effects on their growth and yield. Among these, species like the Brown marmorated stink bug (Halyomorpha halys), Tarnished plant bug (Lygus rugulipennis), and other Lygus species, Nesidiocoris tenuis and the Southern green stink bug (Nezara viridula) pose significant concerns. These plant bugs, known for their piercing-sucking mouthparts, feed on cucumber plants by extracting sap from leaves, stems and fruits.

Spider mites

Spider mites are a frequent pest within cucumber crops. Two-spotted spider mite (Tetranychus urticae) are known for their rapid reproduction and web-spinning behaviour and can inflict considerable damage on cucumber plants. These mites feed on cucumber leaves by puncturing plant cells and extracting their contents, resulting in stippling, discoloration, and reduced photosynthetic activity.

Other pest mites

Also, other pest mite species like the Broad mite (Polyphagotarsonemus latus) are common pests in cucumber cultivation. These mites feed on plant tissues, causing distortion, discoloration, and deformities in leaves, stems, and fruits. Their minuscule size often makes them difficult to detect until substantial damage has occurred.

Thrips

Thrips is a challenging pest in cucumber cultivation, with species like Onion thrips (Thrips tabaci), Western flower thrips (Frankliniella occidentalis) and Impatiens thrips (Echinothrips americanus) causing most problems. Thrips are characterized by their elongated bodies and rasping-sucking mouthparts. Thrips cause damage by piercing plant cells and extracting their contents.

Whitefly

Whitefly poses a significant challenge to cucumber crops. Species like Tobacco whitefly (Bemisia tabaci) and Greenhouse whitefly (Trialeurodes vaporariorum) are the biggest influence. Whiteflies are characterized by their white, powdery appearance and their ability to transmit plant viruses. They feed on cucumber plants by piercing plant tissues and extracting sap, leading to reduced plant vigour, stunted growth, and the potential spread of viral diseases.

Aphid control

For the control of aphids in cucumbers, a diverse array of natural predators and biological control agents are known. These beneficial organisms include the predatory beetle Adalia bipunctata (Aphidalia), the gall midge Aphidoletes aphidymyza (Aphidend), parasitic wasps such as Aphelinus abdominalis (Aphilin), Aphidius colemani (Aphipar), Aphidius matricariae (Aphipar-M), Aphidius ervi (Ervipar, Aphiscout), Praon volucre (Aphiscout) and Ephedrus cerasicola (Aphiscout) and the green lacewing Chrysoperla carnea (Chrysopa, Chrysopa-E). These beneficial organisms play a crucial role in maintaining aphid populations within manageable levels.

Adalia bipunctata, commonly known as the two-spotted ladybird, feeds on aphids and their eggs, while Aphidoletes aphidymyza, a gall midge, preys on aphids in their larval stage. Parasitic wasps such as Aphelinus abdominalis, Aphidius colemani and Aphidius ervi lay their eggs within aphids, ultimately killing them. Additionally, lacewings such as Chrysoperla carnea contribute to aphid control. This web of natural enemies provides a sustainable and eco-friendly approach to managing aphid populations in cucumber crops, enhancing plant health and yield without relying heavily on chemical interventions.

Leaf miner control

Effectively managing leaf miners in cucumber crops is crucial to ensure the plants' vitality and productivity. Diglyphus isaea (Miglyphus), a parasitic wasp, lays its eggs inside leaf miner larvae, ultimately leading to their demise. Dacnusa sibirica (Minusa), another parasitic wasp, plays a crucial role in controlling leaf miner populations by parasitising the larvae.

Mealybug control

Mealybugs can pose a significant threat to cucumbers, but the introduction of natural enemies offers a sustainable solution. Anagyrus vladimiri (Citripar), a parasitic wasp, and Cryptolaemus montrouzieri (Cryptobug and Cryptobug-L), a predatory beetle, stand out as effective solutions. Anagyrus vladimiri lays its eggs inside mealybugs, leading to their eventual death, while Cryptolaemus montrouzieri feeds on both mealybug adults and nymphs.

Caterpillar control

Caterpillars can cause considerable damage to cucumber plants. Insect traps (Deltatrap) in combination with species-specific pheromones help to detect the moths. Introducing the beneficial nematode Steinernema carpocapsae (Capsanem) as a foliar treatment can be an effective strategy in controlling caterpillars. These nematodes seek out and infect caterpillars, leading to their death.

Spider mite and other mite control

Utilising a range of natural enemies is important in the control of spider mites in cucumber cultivation. Predatory mites such as Neoseiulus californicus (Spical, Spical Ulti-Mite, Spical-Plus) and Phytoseiulus persimilis (Spidex, Spidex Boost, Spidex Vital, Spidex Vital Plus) are key natural enemies. These predatory mites feed on spider mites, helping to maintain their populations at manageable levels. Additionally, Feltiella acarisuga (Spidend), a gall midge, contributes to this effort by targeting mite eggs and nymphs. Infestations of broad mite (Polyphagotarsonemus latus) can be managed with the predatory mite Neoseiulus californicus (Spical, Spical Ulti-Mite, Spical-Plus).

Thrips control

Predatory mites such as Amblydromalus limonicus (Limonica), Amblyseius swirskii (Swirski-Mite, Swirski Ulti-Mite, Swirski-Mite Plus, Swirski-Mite LD) or Neoseiulus cucumeris (Thripex, Thripex-Plus, Thripex-V) are effective biological solutions for the control of thrips. Furthermore, predatory bug species such as Orius laevigatus (Thripor-L) contribute by preying on thrips adults and nymphs.

Whitefly control

Predatory mites in combination with parasitic wasps form an effective combination to manage whitefly in cucumber crops. The parasitic wasps Eretmocerus eremicus (Enermix, Ercal) and Encarsia formosa (Enermix, En-Strip) lay their eggs inside whitefly nymphs, effectively suppressing their growth. Additionally, the predatory mites Amblydromalus limonicus (Limonica) and Amblyseius swirskii (Swirski-Mite, Swirski-Mite LD, Swirski-Mite Plus, Swirski Ulti-Mite) contribute to the effort by feeding on whitefly eggs and nymphs. Incorporating Lecanicillium muscarium Ve6 (Mycotal), a biofungicide, further enhances the biological control of whiteflies.

Plant bug control

The beneficial nematode Steinernema feltiae (Entonem) can contribute to the control of some plant bugs. These nematodes plant bug larvae, disrupting their life cycle. By using nematodes, cucumber growers can reduce the need for chemical interventions.

Cucumber crops face a range of potential diseases that can significantly impact their health and productivity. Among these threats are the fungal pathogens Botrytis cinerea, Fusarium oxysporum, Mycosphaerella fijiensis, Phytophtora infestans f.sp. infestans, Podosphaera xanthii and Pythium spp. Botrytis cinerea, commonly known as grey mould, and other fungal diseases, can lead to rapid deterioration of cucumber foliage and fruits, often thriving in humid conditions. Fusarium wilt (Fusarium oxysporum) can cause wilting and vascular damage, while Phytophthora is notorious for causing root rot. Podosphaera xanthii, can weaken plants by impairing photosynthesis. Pythium spp., another root rot pathogen, can thrive in overly wet conditions.

Effectively preventing and controlling diseases in cucumber crops is pivotal for sustaining health and maximising yields. Incorporating disease-resistant cucumber varieties, practising proper crop spacing, ventilation and irrigation, and implementing regular scouting, are fundamental steps. To enhance disease management, consider incorporating beneficial biological microorganisms such as Trianum-P and Trianum-G. These biofungicides, developed by Koppert, contain Trichoderma harzianum strain T22 that establishes a shield around the plant roots, which protects the plants against the soil-borne pathogens Pythium, Fusarium and Rhizoctonia, enhancing plant resilience.