Nematode community composition and ecological indicators in cabbage, Brassica oleracea L. rhizosphere soils of Eastern Fergana Valley, Uzbekistan

Abstract

This study examines the species composition, trophic structure, and ecological functioning of soil nematode communities in the rhizosphere of cabbage, Brassica oleracea L. (Brassicales: Brassicaceae) agroecosystems across six districts of the Eastern Fergana Valley, Uzbekistan. To investigate the nematode fauna associated with cabbage plants, field studies were conducted in six districts located in the southeastern part of the Fergana Valley. The research was carried out during the spring and autumn seasons of 2024-2025. A total of 38 nematode species belonging to five orders were identified, reflecting considerable variation in faunal structure among sampling sites. Ecological indices, including the Maturity Index (MI), Enrichment Index (EI), Structure Index (SI), Plant-Parasitic Index (PPI), and Channel Index (CI), were used to assess soil food web status and ecosystem stability. Enrichment-dominated systems, particularly in Marhamat, were characterized by high EI values and the dominance of bacterivorous nematodes, whereas more mature and structured food webs were evident in districts such as Khojaobod and Buloqboshi, where higher MI and SI values were recorded. These findings highlight the diagnostic value of nematode-based indicators for evaluating soil health and emphasize the need for district-specific management strategies to support sustainable agricultural productivity in the region.

Keywords

• Agroecosystems
• cabbage
• ecological indicators
• nematodes
• nematode community
• soil

Supporting Institution

Andijan State University, Scientific Research Unit

Ethical Statement

The authors declare that they have no conflict of interest

Thanks

The authors express their sincere gratitude to Andijan State University for providing the necessary scientific equipment and organizational support required for the implementation of this research. We also extend our heartfelt thanks to the staff of the Laboratory of the Department of Biology at the university for their invaluable assistance during sample processing and analysis. Furthermore, we gratefully acknowledge the constructive comments and insightful suggestions of the anonymous official reviewers, which significantly contributed to improving the quality of the manuscript. In addition, we express our deep appreciation to Shukurullo Foziljonov, a master’s student in Biotechnologies and Applied Artificial Intelligence for Health at the Faculty of Biology, University of Pisa (Italy), for his kind support and valuable assistance during the course of this study.

Özbekistan'ın Doğu Fergana Vadisi'ndeki lahana, Brassica oleracea L. ekiliş alanlarında tespit edilen toprak nematodlarının topluluk ve ekolojik analizi

Abstract

Bu çalışma, Özbekistan'ın Doğu Fergana Vadisi'ndeki altı bölgede bulunan lahana, Brassica oleracea L. (Brassicales: Brassicaceae) tarım ekosistemlerinin rizosferindeki toprak nematod topluluklarının tür bileşimini, trofik yapısını ve ekolojik işlevini incelemektedir. Lahana bitkileriyle ilişkili nematod faunasını araştırmak amacıyla, Fergana Vadisi'nin güneydoğu kesiminde yer alan altı bölgede saha çalışmaları yürütülmüştür. Araştırma, 2024-2025 ilkbahar ve sonbahar mevsimlerinde gerçekleştirilmiştir. Bu çalışmada, toplamda beş takıma ait 38 nematod türü tanımlanmış olup, örnekleme alanları arasında fauna yapısında önemli bir varyasyon gözlemlenmiştir. Toprak besin ağı durumunu ve ekosistem istikrarını değerlendirmek için Olgunluk İndeksi (MI), Zenginleşme İndeksi (EI), Yapı İndeksi (SI), Bitki-Parazit İndeksi (PPI) ve Kanal İndeksi (CI) gibi ekolojik indeksler kullanılmıştır. Özellikle Marhamat'ta zenginleşmenin baskın olduğu sistemler, yüksek EI değerleri ve bakteri ile beslenen nematodların baskınlığı ile karakterize edilirken, Khojaobod ve Buloqboshi gibi bölgelerde daha olgun yapılaşmış besin ağları gözlemlenmiştir. Bu bulgular, toprak sağlığını değerlendirmek için nematod bazlı toprak sağlığının değerlendirilmesindeki önemini ve bölgede sürdürülebilir tarımsal verimliliği desteklemek için bölgeye özgü yönetim stratejilerine duyulan ihtiyacı vurgulamaktadır.

Keywords

• Tarım ekosistemleri
• ekolojik göstergeler
• lahana
• nematodlar
• nematod topluluğu
• toprak

Supporting Institution

Andijan State Üniversitesi, Bilimsel Araştırmalar Birimi

Ethical Statement

Yazarlar herhangi bir çıkar çatışması olmadığını beyan ederler.

Thanks

Yazarlar, bu araştırmanın yürütülmesi için gerekli bilimsel ekipman ve organizasyonel desteği sağlayan Andijan Devlet Üniversitesi'ne içten şükranlarını sunarlar. Ayrıca, örnek işleme ve analiz sırasında paha biçilmez yardımları için üniversitenin Biyoloji Bölümü Laboratuvarı personeline de yürekten teşekkürlerimizi sunarız. Dahası, makalenin kalitesinin iyileştirilmesine önemli ölçüde katkıda bulunan isimsiz hakemlerin yapıcı yorumları ve değerli önerileri için minnettarız. Ek olarak, bu çalışma süresince gösterdiği nazik destek ve değerli yardımları için Pisa Üniversitesi (İtalya) Biyoloji Fakültesi'nde Biyoteknolojiler ve Sağlıkta Uygulamalı Yapay Zeka alanında yüksek lisans öğrencisi olan Shukurullo Foziljonov'a derin şükranlarımızı sunarız.

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