Important Passion Fruit Pests

Which are the major pests infesting passion fruit?

Root knots and cysts 

Nematodes that invade the roots are the most common pests on Passiflora species. Nematodes and 2 fungi, species of Phytophthora and Fusarium, have been found on the roots of declining or drying vines. The yellow passion vine is more resistant to harmful soil organisms than the purple, but it is not immune. The most important, which causes extreme thickening of the roots, is the root-knot nematode, Meloidogyne javanica. Others include the spiral nematode and the lesion nematode. Meloidogyne spp attacks the plants by injecting certain toxic substances into the roots leading to the formation of root – knots and cysts. To effectively manage nematode infestation, several recommended measures include the utilization of healthy seedlings, implementing crop rotation with plants that are not favorable hosts for nematodes, employing solarization techniques, incorporating fallow periods, and considering the use of nematicides. These strategies aim to control and reduce nematode populations in agricultural systems.

Root-knot nematode, Meloidogyne javanica (Joy et al.,2012)

Primary Pests of Passion Fruit

Mites

Brevipalpus phoenicis and red spider mites Tetranychus mexicanus and T. desertorum B are known to infest passion fruit. Infestations of the passion vine mite (Brevipalpus phoenicis) occur during dry weather in the warm season, defoliate the younger portions of the vines but not the terminus, and make brown blemishes on the fruits, which results in lower quality. Mites can be observed scattered in reddish patches on the fruit’s surface, particularly near the stem end, along the midrib, and veins of the underside of the leaves. The presence of Brevipalpus phoenicis leads to a general discoloration of the leaves, accompanied by necrosis that eventually results in leaf drop. Young stems that are affected dry out starting from the tip and progress towards the base, eventually leading to their death. As infestation becomes more severe and prolonged, there is an increased occurrence of leaf fall, giving the vine the appearance of wilting. Concurrently, developing fruits may start to shrink and prematurely detach from the plant. If left uncontrolled, red spider mites can ultimately cause the plant to perish. Dense populations of spider mites create webbing that covers the leaves, and heavy infestations result in leaf loss and reduced plant vitality. To control their populations, you need to do periodic inspection to the orchard and the crops around to identify the contamination at early stages. Also, you can spray neem or Pongamia soap at 1% on the lower surface.

Natural mite predators are Anthocorid bugs, mirid bugs, predatory cecidomyiid fly, green lacewings, predatory mites), predatory coccinellids (Stethorus sp.), predatory gall midge, etc. (Joy et al, 2013)

Lepidopterous Defoliators

Dione juno juno, Agraulis vanillae vanillae and Eueides isabella huebneri (Nymphalidae), are the most common lepidopterans infesting and eating the foliage of passion fruit. Dione juno juno can cause severe damage in the plant. By reducing the leaf area, this insects they reduce indirectly the yield. Apart from the foliage, they can feed on the buds and the flowers.To control their populations farmers can apply foliar sprays to protect the passion fruit crop from pests, starting from the initial appearance of the pests and continuing at regular intervals until harvest. In order to safeguard pollinating insects, it is crucial to time insecticidal treatments when pollinators are absent from the field. When selecting an insecticide, it is important to choose one that targets the specific pest while being less harmful to pollinators, predators, and parasitoids, as these beneficial organisms play a valuable role in the agro-ecosystem (Joy et al, 2013)

(A) Eggs of Agraulis vanillae vanillae, (B) Larvae (C) Adult Agraulis vanillae vanillae (Joy et al, 2013)

Stem Weevil

The larvae of Philonis spp. insects feed within the stems, creating longitudinal galleries that hinder the plant’s growth and development. Infested stems can be easily identified by the presence of excrement and sawdust. As the larvae grow, the affected stems become weak, fragile, and eventually die. Infestations by weevils often involve multiple larvae attacking the stems, leading to the hypertrophy of the stems where the pupal cell will be formed. This weevil infestation also results in premature fruit drop before reaching maturity. Controlling fruit flies involves several important measures. It is crucial to eliminate over-ripe fruits, as they serve as breeding sites for the flies and attract adult flies for feeding. Passion fruit should be planted away from coffee plantations, and any wild host plants growing near the passion fruit crop should be removed. 

Bugs

The passion vine bug Diactor bilineatus feeds on flowers and young, green fruits. The stinkbug is a similar but lesser menace to the plant and young fruits. Both young and mature insects cause damage to the passion fruit crop by piercing the stems, leaves, fruits, and flower buds and extracting plant juices through feeding. However, the nymphs tend to target the flowering buds and young fruits, often leading to significant fruit drop. The adult bugs can also attack leaves, stems, and fruits at various stages of ripening. When feeding on larger fruits, they cause wilting and result in a wrinkled appearance on the fruit’s surface. (Joy et al, 2013)

Diactor bilineatus nymph © Sergio Monteiro, Project Noah

Flies

The fruit fly, Bactrocera dorsalis and the melon fly, Bactrocera cucurbitae, are known to attack passion fruit plants. However, depending on the location we can find also other species such as Anastrepha sp. or Lonchaea sp. deposit eggs in the very young, tender fruits. Flies belonging to various species feed on the fruits and flowering buds of passion fruit. Fruit flies cause damage by laying their eggs in green fruits, resulting in deformities on the fruit’s surface. The larvae then feed on the fruit pulp, leading to contamination by bacteria and fungi and causing premature fruit drop. Melon, and Mediterranean fruit flies puncture the fruit while the rind is still tender. As the fruit grows, a woody area forms around the puncture site. If the fruit is small and underdeveloped, the damage may cause it to wither and fall off the plant. However, if the fruit is well-developed, it can continue to mature. During ripening, the puncture area forms a small woody crater, which affects the fruit’s appearance but not its pulp quality. Although ripening fruits may have oviposition scars, they usually do not contain live larvae. Larvae tend to develop better in immature fruit than in mature ones. 

Secondary Pests of Passion Fruit

Mealybugs (Planococcus citri)

The citrus mealybug, P. citri, is a small, oval-shaped insect that feeds by sucking on the passion fruit plant. It is a major pest in dry weather that may also induce sooty mold from excretions that encourage the growth of molds on leaves. In a severe infestation, we observe the loss of vigor, leaf drop, and fruit malformation. Natural enemies of mealy bugs are Cryptolaemus montrouzieri, Lacewing larvae, Coccophagus sp., Anagyrus coccidivorus, Leptomatrix dactylopii.

Aphids

Aphids are responsible for malformation in the foliage and the transmission of various diseases. The aphids Aphis gossypii and Myzus Persicae, transmit the virus which causes hardening of fruits. Additionally, M. persicae and M. solanifolii are vectors of the virus that cause “passion fruit woodiness”. To control aphids, avoid high levels of nitrogen and release natural aphid predators such as Chrysoperla zastrowii sillemi.

Thrips

Thrips injure and cause stunting of young seedlings in nurseries. In dry weather, they feed on leaves and fruits, leaving them defaced and likely to shrivel and fall prematurely.

Injury from the tobacco white fly (Bemisia tabaci) may lead to galls on the leaves. 

Scales

Among scales attacking passion fruit, the soft brown scale (Coccus hesperidum) occasionally infests leaves and stems, and California red scale, Aonidiella aurantii is common on older passion fruit vines. Scales injure the passion fruit by sucking the sap. Sometimes, they can also encrust the leaves, the branches, and the fruits. In case the infestation is very severe, they can kill the plant. In case of severe infestations, use sprays of white oil. If needed, you can spray horticultural oil all year round. Conserve (or release) populations of Aphytis spp. 

IPM Strategies

Ιt is crucial to identify the cause and implement appropriate preventive measures accurately. Prevention is the key to managing fruit pests and diseases.

Management in the Nursery

Nurseries should be located in a place isolated from other fruit tree plants. It is preferable to rotate the nursery site, if possible, or at least to change the part of the nursery where fruit seedlings are raised each year (being careful to destroy all old fruit plants in the nursery first). If the seeds are first sown into beds and later transplanted to pots/other beds, it is essential to space the seeds 1 cm apart in the lines, with 10 cm between the lines. Closer spacing fosters the development and spread of disease. Once they have emerged and have 2 true leaves, seedlings should be “pricked out”, preferably into plastic bags/pots. The nursery should be carefully inspected every day, and all seedlings exhibiting any signs of disease or insect infestation should be removed and destroyed.

To avoid diseases and insects, it is recommended to:

• Use resistant varieties 
• Summer deep plowing to expose soil-inhabiting stages of various insects/pathogens. 
• Have a proper drainage system to remove excess water.
• Trimming the orchard bunds to destroy rodent burrows. 
• Only seeds of known origin should be used.
• Grow tall barrier crops for aphids managements, 
• Uproot and burn early infected plans to avoid the spread of the diseases

Disease Management during Planting 

• Well-decomposed manure should be incorporated into the soil to a depth of 40 to 50 cm at least 4 weeks before planting in the planting hole.

For weed management

• Remove existing weeds
• Use planting material that is free from weeds
• Use seasonal vegetables as intercrop. Examples are chili, soybean, mustard, ginger, turmeric leafy vegetables)

Diseases Management during the Vegetative Growth

• Fields should be inspected at least once a week; 
• Plants showing disease symptoms should be uprooted, taken out of the field and destroyed.
• All fallen plant material (fruits, leaves) must be regularly collected and removed from the field.
• Provide irrigation only at critical stages. 
• Use biological control to avoid chemical sprays when 1-2 larval parasitoids are observed.
• Collect rotten fruits, twigs and leaves.  Leaves/fruits/shoots with signs of fungal disease should be removed and destroyed.
• Pruning should be restricted to the lower part of the vines hanging on the ground during winter when vines are dormant.
• Use yellow sticky traps for aphids and whitefly and blue sticky trap for thrips.
• Conserve and protect natural enemies.
• Use augmentative biological control of natural enemies.
• Weed control should be performed with caution to avoid damage to the plants.
• It is advisable to plant windbreaks of species such as sesbania to reduce the wind-blown dispersal of diseases and insects.
• Avoid harvesting during wet conditions
• Tools such as secateurs and knives should be sterilized, between each plant. 
• Tools and workers’ hands should be cleaned after working in one field before going to the other. 
• Workers should always start in the youngest plantations and move from them to progressively older ones; this will reduce likelihood of diseases/pests being carried from the older (and more likely to be infected) into the younger (and more susceptible) plantings.

Diseases Management during the Reproductive phase of passion fruit

• Remove the weeds with caution
• Destroy crop debris.
• Use biological control to avoid chemical sprays when 1-2 larval parasitoids are observed.
• Collect and destroy rotten fruits, twigs and leaves.
• Try to avoid leaving overripe fruits, which are an excellent medium for flies to feed and breed.
• Install at least 10 traps/ha to monitor fruit flies. 
• Use bottle traps

Cautions

• Many producers are tempted to leave old plant materials in the field, believing them to be a source of “fertilizer” when they decompose after falling; it is better to remove all dead plant materials, to reduce the risk of leaving potentially infected material in the field where it can contaminate the crop. While pruning is in all cases, advised, pruning tools must be cleaned between plants to prevent the spread of disease.
• Use a wide spacing between fruit plants and intercrop where possible. Wider spacing is recommended to both reduce the likelihood of disease transmission and prevent the build-up of humidity within the crop’s environment.

• Diseases, especially viral diseases, are more likely to occur in mono-cropped fruit fields, particularly when planted at close spacing and in proximity to other fruit crops. Intercropping with species allows producers to use a wider spacing without wasting limited land; the increase in plant diversity may also contribute to reduced risk of disease and/or insect infestation.
• Keep the soil covered with a thick layer of organic matter as mulch. This helps maintain soil humidity during the dry season, reduces splash of soil-borne diseases on the plant during heavy rains, and reduces the emergence of pests such as thrips which pupate in the soil.
• The composition of the soil will affect the pest population. Nematodes thrive in sandy soils. Clay makes possible permanent burrows of some cutworms. A loamy, friable soil, kept in good condition by frequent addition of compost, is a better alternative. A rich, organic soil, with its many forms of living organisms, discourages the buildup or dominance of any one pest, and often is, in itself, a control measure. Cultivation of the soil is sometimes useful in pest control. Insect eggs and pupae are often disrupted and destroyed. Nematodes are reduced by exposure to air and sun (solarisation). 
• A simple trap for slugs and snails, for example, can be nothing more than a few planks left on the soil surface. Slugs and snails hide under these and can easily be collected by lifting the boards, scraping the pests off, and feeding them to the chickens.

References 

Kashyap PL, Kumar S, Srivastava AK (2017) Nano diagnostics for plant pathogens. Environ Chem Lett 15:7– 13. 

Joy P. P. & Sherin C.G. 2012. Pineapple Research Station (Kerala Agricultural University), Vazhakulam-686 670, Muvattupuzha, Ernakulam, Kerala, India. Tel. & Fax: 0485-2260832, Email: [email protected], [email protected], Web: www.kau.edu/prsvkm

Joy P. P. & Sherin C.G. 2013. Pineapple Research Station (Kerala Agricultural University), Vazhakulam-686 670, Muvattupuzha, Ernakulam, Kerala, India. Tel. & Fax: 0485-2260832, Email: [email protected], [email protected], Web: www.kau.edu/prsvkm

Diseases fro Passionfruit, 2023 NZ Passionfruit Growers Association

Passion Fruit – Crop Stage Wise IPM, Vikaspedia, Ministry of Electronics & Information Technology

Further reading

• Passion Fruit: History, Uses and Nutritional value
• Passion fruit: Types-Varieties of Passion Fruit and Plant Characteristics
• Passion Fruit: Soil & Climate Requirements, Land Preparation and Planting
• Propagation and Trellising of Passion Fruit plants
• Training and Pruning of Passion Fruit Plant
• Passion Fruit Plant Care: Irrigation and Fertilization of Passion Fruit
• Important Passion Fruit Diseases
• Important Passion Fruit Pests
• Passion Fruit: Harvest, Yield and Storage