How can a nematode be distinguished from a mite on strawberries? - briefly
Nematodes appear as microscopic, slender, translucent worms that require magnification to see, whereas mites are visible to the naked eye as tiny, oval-shaped arthropods with eight legs moving on the fruit surface. Microscopic inspection shows nematodes as elongated, featureless bodies, while mites display a segmented form with distinct leg pairs.
How can a nematode be distinguished from a mite on strawberries? - in detail
Nematodes and mites are distinct organisms that can both infest strawberry crops, but they differ in size, anatomy, habitat, and detection methods.
Nematodes are microscopic, elongated roundworms usually 0.2–1 mm long. Their bodies are cylindrical, lack segmentation, and possess a slender, tapered tail. They live in the soil and feed on plant roots, causing galling, stunted growth, and reduced fruit quality. Common species on strawberries include Meloidogyne (root‑knot) and Pratylenchus (lesion) nematodes.
Mites are arthropods, typically 0.1–0.5 mm in length, with a flattened, segmented body covered by a hard exoskeleton. They inhabit leaf surfaces, flower buds, and fruit, feeding on plant tissue and excreting silk or webbing. The most frequent strawberry mite is Tetranychus (spider mite), which creates stippled leaves and yellowing.
Key distinguishing features:
- Location: nematodes reside in the rhizosphere; mites are found on aerial parts.
- Visibility: nematodes require magnification (10×–40×) to be seen; mites can be observed with a hand lens (30×) or under a microscope.
- Shape: nematodes are worm‑like, lacking legs; mites have a segmented, legged body with distinct dorsal shield.
- Movement: nematodes move through soil by sinusoidal motion; mites crawl on plant surfaces and may spin webs.
- Damage pattern: nematodes produce root galls, lesions, and overall vigor loss; mites cause leaf discoloration, stippling, and webbing.
Practical steps for accurate identification:
- Soil sampling – collect root and soil cores from symptomatic plants, wash roots, and extract nematodes using Baermann funnels or centrifugal flotation. Observe under a compound microscope for characteristic stylet and esophageal morphology.
- Leaf/fruit inspection – examine foliage and fruit under a stereomicroscope or hand lens. Look for mite bodies, egg sacs, and webbing. Use a fine brush to collect specimens for slide mounting.
- Molecular confirmation – apply PCR assays with species‑specific primers for nematodes (e.g., Meloidogyne spp.) or mites (e.g., Tetranychus spp.) when morphological identification is ambiguous.
- Damage assessment – correlate observed organisms with symptoms: root galling indicates nematodes; stippled leaves and webbing point to mites.
By focusing on habitat, morphology, and diagnostic procedures, growers can reliably separate nematode infestations from mite problems on strawberries and implement targeted control measures.