DefinePK

Research Objective

To conduct surveys to isolate, identify, and determine the infectivity of plant-parasitic nematodes on apricot and walnut trees in Lawat Valley, Pakistan, with a specific focus on identifying new species.

Methodology

Soil and root samples (250 in total) were collected from seven different localities in the Lawat area of Neelum district, Pakistan, during 2018-2020, at a depth of 10-20 cm. Nematodes were extracted using the Baermann funnel method and decanting by Cobb sieving method. Nematodes were killed with boiled water (80ºC) and fixed in TAF. They were then transferred to glycerin using the Seinhorst method. Identification was performed using a compound microscope with an ocular micrometer and based on the systematics provided by Siddiqi (2000). Measurements were taken using de Man's (1884) formula.

Methodology Flowchart

                        graph TD;
    A[Sample Collection Soil & Roots] --> B[Nematode Extraction];
    B --> C[Nematode Preparation];
    C --> D[Nematode Identification];
    D --> E[New Species Identified?];
    E -- Yes --> F[Description of Cephalenchus regia n. sp.];
    E -- No --> G[Identification of Known Species];
    F --> H[Conclusion];
    G --> H;                    

Discussion

The study highlights the presence of plant-parasitic nematodes in the Lawat Valley, a region previously under-surveyed for these organisms. The identification of Cephalenchus regia n. sp. contributes to the understanding of nematode diversity in Pakistan and provides specific morphological characteristics that differentiate it from closely related species like C. nemoralis, C. longicaudatus, and C. sacchari.

Key Findings

A total of six nematode species were identified in apricot trees and seven in walnut trees. A newly identified species, Cephalenchus regia n.sp., was found in the soil around the dry fruit of walnut (Juglans regia) in Lawat Kundian. This new species is distinguished by its longer stylet, pharynx, and tail, as well as an anteriorly situated vulva compared to other known species.

Conclusion

The research successfully identified a new nematode species, Cephalenchus regia n. sp., associated with walnut trees in Lawat Kundiyan, district Neelum, Azad Kashmir, Pakistan. This finding expands the knowledge of plant-parasitic nematodes in the region.

Fact Check

- Surveys were conducted from 2018-2020. (Confirmed by the text stating "during 2018-2020" in the abstract and introduction).
- A total of 250 soil and root samples were collected. (Confirmed by the text stating "A total of 250 samples of soil and roots were collected" in the abstract and "250 soil samples were collected" in Material and Methods).
- The new species, Cephalenchus regia n. sp., has a stylet measuring 22-24 µm. (Confirmed by the "Measurements" section for females: "Stylet = 23 ± 0.81 (22-24) µm").

Mind Map