Diversity and Management Strategies of Plant Parasitic Nematodes in Moroccan Organic Farming and Their Relationship with Soil Physico-Chemical Properties

Organic farming has been increasing steadily over the last decade and is expected to grow drastically in the future. Plant parasitic nematodes (PPNs) are known as one of the most important pests attacking various plants in conventional and organic farming systems. A survey was conducted in January 2019 to determine the occurrence and diversity of PPNs, their associations with soil properties, and to assess their management methods in organically farmed fields in Southern Morocco. Twelve genera of PPNs were identified in soil and root samples collected from 53 organic fields, including Meloidogyne, Pratylenchus, Helicotylenchus, Tylenchus, Tylenchorynchus, Criconemoides, Trichodorus, and Xiphinema. The root-knot nematodes (Meloidogyne spp.) and the root-lesion nematode (Pratylenchus spp.) were the most prevalent PPNs. Vegetable crops (bean, onion, and tomato) had high nematode diversity indices compared to some aromatic and medicinal crops, including the Shannon, Evenness, and plant parasitic index (PPI). Our study underlined that several PPN genera were significantly correlated with soil physico-chemical properties, in particular, soil structure and organic matter. Therefore, it was concluded that soil properties have a considerable impact on PPN communities in organic farming systems located in Southern Morocco. There are numerous strategies for the control of PPNs in organic farming systems.

Download Full-text

Oilseed radish/black oat subsidiary crops can help regulate plant-parasitic nematodes under non-inversion tillage in an organic wheat-potato rotation

Nematology ◽

10.1163/15685411-00003113 ◽

2017 ◽

Vol 19 (10) ◽

pp. 1135-1146 ◽

Cited By ~ 6

Author(s):

Jan H. Schmidt ◽

Maria R. Finckh ◽

Johannes Hallmann

Keyword(s):

Parasitic Nematode ◽

Farming Systems ◽

Conventional Tillage ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Tillage Systems ◽

Oilseed Radish ◽

Organic Farming Systems ◽

Potato Rotation ◽

Plant Parasitic

Soil conservation is one of the major challenges for agriculture in the 21st century. For this reason, non-inversion tillage systems including subsidiary crops have become popular over the last three decades in Europe. However, the adoption of new agricultural practices may change the diversity and abundance of certain pests and diseases. For example, plant-parasitic nematodes that are major threats towards cultivated plants may be promoted if good hosts, such as certain subsidiary crops and weeds, occur more frequently. The indigenous plant-parasitic nematode fauna under organic farming systems is already adapted to diverse crop rotations and usually dominated by nematodes with broad host ranges. These may be further enhanced in organic farming systems if non-inversion tillage is introduced, which generally increases the abundance and biomass of certain weeds. We evaluated the early effects of non-inversion tillage and subsidiary crops in an organic wheat-potato rotation on plant-parasitic nematodes in two field experiments in two successive years. The total densities of plant-parasitic nematodes increased from an initial 1260 nematodes (100 ml soil)−1 at the start of the experiment to 1850 and 1700 nematodes (100 ml soil)−1 after wheat under non-inversion and conventional tillage, respectively. Plant-parasitic nematode densities then decreased on average to 1100 and 560 nematodes (100 ml soil)−1 after subsidiary crops and potatoes, respectively. Parasitic nematode densities tended to be higher under non-inversion than conventional tillage, except where oilseed radish and black oats had been used as cover crops. For the latter, no differences between tillage treatments occurred. In the second experiment, about 1700 free-living nematodes (100 ml soil)−1 were found under conventional tillage without mulch while under reduced tillage with mulch their numbers were significantly higher at 3100 nematodes (100 ml soil)−1. We conclude that an appropriate choice of subsidiary crops can be an important management factor for the long term sustainability of non-inversion tillage systems.

Download Full-text

Distribution and community structure of plant-parasitic nematodes and their relationship with some soil properties in betel vine-growing regions of West Bengal, India

Nematology ◽

10.1163/15685411-00003237 ◽

2019 ◽

Vol 21 (6) ◽

pp. 581-595 ◽

Cited By ~ 1

Author(s):

Sandip Mondal ◽

Prahlad Sarkar ◽

Amit Singh ◽

Matiyar Rahaman Khan ◽

Abhishek Mukherjee

Keyword(s):

Spatial Distribution ◽

Community Structure ◽

Soil Properties ◽

West Bengal ◽

Chemical Properties ◽

Parasitic Nematodes ◽

Piper Betle ◽

Plant Parasitic Nematodes ◽

The North ◽

Plant Parasitic

Summary The distribution and community structure of plant-parasitic nematodes associated with betel (Piper betle) vine and their relationship with soil chemical properties were investigated in four major growing regions of West Bengal, India. Ordinary kriging method was applied to infer the patterns of spatial distribution of major plant-parasitic nematodes across the growing regions. Meloidogyne and Rotylenchulus were found to be the most abundant genera in betel vine crops in all growing regions. Co-inertia analysis between soil properties and nematode abundance indicated that soil chemical characters significantly affect abundances of plant-parasitic nematodes. The type of betel vine crop (sweet and bitter) also has a significant effect on the abundance of plant-parasitic nematodes, with the highest abundance of Meloidogyne reported from the bitter type of betel crop. Spatial distribution depicted a higher abundance of Meloidogyne throughout the North Bengal growing region. Root-knot and reniform nematodes are two important plant-parasitic nematodes of betel vine that might cause economic yield loss to the growers in West Bengal.

Download Full-text

The association of plant parasitic nematodes with fruit crops in Poland as related to some soil properties

Fragmenta Faunistica ◽

10.3161/00159301ff2004.47.1.007 ◽

2004 ◽

Vol 47 (1) ◽

pp. 7-33 ◽

Cited By ~ 2

Author(s):

Adam Szczygieł ◽

Alojzy Zepp

Keyword(s):

Soil Properties ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Fruit Crops ◽

Plant Parasitic

Download Full-text

Occurrence and distribution of vermiform plant-parasitic nematodes and the relationship with soil factors in field pea (Pisum sativum) in North Dakota, USA

Nematology ◽

10.1163/15685411-00003225 ◽

2019 ◽

Vol 21 (5) ◽

pp. 445-457 ◽

Cited By ~ 3

Author(s):

Arjun Upadhaya ◽

Guiping Yan ◽

Julie Pasche ◽

Audrey Kalil

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Field Pea ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Soil Factors ◽

The Usa ◽

Nematode Abundance ◽

The Relationship ◽

Plant Parasitic

Summary Plant-parasitic nematodes restrict crop growth and cause yield loss in field pea (dry edible pea). A 4-year survey of commercial pea fields was conducted in North Dakota, one of the leading producers of field pea in the USA, to investigate nematode distribution, prevalence, abundance and association with soil properties. Beginning in 2014, a total of 243 soil samples were collected from 16 counties, and soil properties of 115 samples were analysed to determine the association of nematodes with soil factors (texture, organic matter, nutrients). The plant-parasitic nematode genera, Paratylenchus (absolute frequency = 58-100%; mean density = 470-1550 (200 g soil)−1; greatest density = 7114 (200 g soil)−1) and Tylenchorhynchus (30-80%; 61-261; 1980, respectively), were the most frequent and widely distributed. Pratylenchus and Helicotylenchus were identified in one-third of the counties surveyed with mean densities ranging from 43 to 224 and 36 to 206 (200 g soil)−1, respectively. Xiphinema was found relatively frequently but at low densities. Hoplolaimus and Paratrichodorus were rarely detected at lower densities. Canonical correspondence analysis revealed that soil factors explained 19% of the total variance of nematode genera abundance. The relationship between nematode abundance and soil sand content and pH was significant, while clay, silt, organic matter and nutrients were not significantly related to nematode abundance. This is the first multi-year study investigating nematodes associated with field peas and their relationship with soil factors in a major field pea production region of the USA.

Download Full-text

Five Species of Plant Parasitic Nematodes (Order: Tylenchidae) Affecting Vegetable Crops of Nepal

International Journal of Life Sciences ◽

10.3126/ijls.v10i1.14515 ◽

2016 ◽

Vol 10 (1) ◽

pp. 10-14

Author(s):

Arvind K. Keshari ◽

Ranjana Gupta

Keyword(s):

Life Sciences ◽

Nematode Species ◽

Parasitic Nematodes ◽

Kathmandu Valley ◽

Vegetable Crops ◽

Plant Parasitic Nematodes ◽

Morphometric Data ◽

First Time ◽

Plant Parasitic

During a survey for plant parasitic nematodes affecting various vegetable crops grown in three hilly districts surrounding Kathmandu Valley, Nepal, five species of order Tylenchidae are reported for the first time from Nepal.The nematode species are Hoplolaimus indicus, Tylenchorhynchus mashhoodi, Helicotylenchus incisus, Microposthonia paraxestis and Hemicriconemoides cocophilus.All the species are illustrated with line diagrams and described with their morphometric data along with localities and host plants.International Journal of Life Sciences 10 (1) : 2016; 10-16

Download Full-text

Occurrence and importance of plant-parasitic nematodes in organic farming in Germany

Nematology ◽

10.1163/156854107782331261 ◽

2007 ◽

Vol 9 (6) ◽

pp. 869-879 ◽

Cited By ~ 16

Author(s):

Andrea Frankenberg ◽

Andreas Paffrath ◽

Johannes Hallmann ◽

Harald Schmidt

Keyword(s):

Organic Farming ◽

High Frequency ◽

Production Systems ◽

Parasitic Nematodes ◽

Yield Losses ◽

Plant Parasitic Nematodes ◽

Severe Damage ◽

Production Factors ◽

Main Emphasis ◽

Plant Parasitic

AbstractIn an attempt to evaluate the occurrence and economic importance of plant-parasitic nematodes in organic farming in Germany, a survey was conducted with the main emphasis on vegetable and cereal production systems. For vegetables, the survey included quantification and identification of plant-parasitic nematodes in soil samples and a questionnaire for growers querying production factors and damage levels. For cereals, the survey focused on quantification and identification of plant-parasitic nematodes in soil and plant samples. Overall, Pratylenchus and Tylenchorhynchus were the most prominent nematode genera under both production systems with an incidence of over 90% of the samples. Meloidogyne was detected in 51% of the samples in both systems. Other nematode genera showed differences between the two production systems. In production systems with a high frequency of vegetables, Paratylenchus was detected in 56% of the samples and Heterodera in 15%, whereas in rotations with a high cropping frequency of cereals, incidences of plant-parasitic nematodes were 56% for Heterodera, 47% for Trichodorus and 45% for Paratylenchus. Yield losses could exceed 50% on carrots, onions and cereals and were most pronounced on sandy soils. In many cases, nematode problems started 5 to 10 years after conversion to organic farming. The survey indicated that plant-parasitic nematodes are widely spread in organic farming in Germany and can cause severe damage which may result in complete loss of the crop.

Download Full-text

First report on four species of predatorynematodes, mononchids (Nematoda : Mononchida) from Nepal

Journal of Applied and Advanced Research ◽

10.21839/jaar.2018.v3i5.223 ◽

2018 ◽

Vol 3 (5) ◽

pp. 139

Author(s):

Arvind K. Keshari ◽

M.M. Shah ◽

R. Gupta

Keyword(s):

Parasitic Nematodes ◽

Vegetable Crops ◽

Plant Parasitic Nematodes ◽

First Report ◽

Plant Parasitic

A nematological survey was conducted for free and plant nematodes affecting economically important vegetable crops grown in Bhaktapur and Kavre, hilly districts of Nepal with altitudes ranging between 1315m to 1500m which revealed various plant parasitic nematodes along with four species of predatory nematodes belonging to the order Mononchida. These species were Mononchus aquaticus Coetzee, 1968, Iotonchus indicus Jairajpuri 1969, Mylonchulus contractus Jairajpuri, 1970 and Parahandronchus shakili (Jairajpuri, 1969) Mulvey, 1978. The measurements, descriptions, remarks and illustrations along with habitat and locality of these predatory nematodes are provided. These species are the first report from Nepal.

Download Full-text