Incidence Of Nematodes Research Articles

Incidence and diversity of plant-parasitic nematodes associated with wheat-cropping systems in the inner part of the Aegean Region of Turkey

Summary Plant-parasitic nematodes are among the most influential soil organisms worldwide and have a detrimental impact on wheat productivity; they also play a major role in maintaining soil diversity. However, limited information is available on the biodiversity of nematodes associated with wheat cropping systems in Turkey. To address this knowledge gap, 45 wheat fields in the Afyonkarahisar Province of Turkey were sampled in 2021 in order to extract and identify nematodes. A total of 14 genera and 44 species of these nematodes were identified based on their physical traits and ITS DNA sequences examination. Shannon diversity index was used to determine the prevalence and biodiversity features of these nematodes. This study represents the first comprehensive research on plant-parasitic nematodes from wheat-growing regions in the Afyonkarahisar Province. The genera Helicotylenchus, Heterodera, Merlinius, Pratylenchoides and Pratylenchus dominated with a high relative abundance percentage >60%, and were extremely common (>90% for each). The average Shannon index of nematode species in the wheat fields was 2.20, with an evenness value of 0.81, indicating moderate diversification and good nematode evenness. This study also revealed a significant correlation between nematode genus biodiversity and edaphic, climatic and geographical factors. Finally, this research demonstrated a remarkable diversity of soil nematodes associated with wheat crops and they have the potential to be useful tools for extensive soil bio-study.

An Innovative Approach for Biocontrol of Meloidogyne incognita in Ginger Using Potential Bacteria Isolated from Indian Himalayas.

The prevalence of Meloidogyne incognita, a severe root-knot nematode, is alarmingly high in the production of ginger-a main cash crop of Himachal Pradesh, a Himalayan state of India. In order to control this through natural means, the nematicidal potential of plant growth-promoting rhizobacteria (PGPR) against M. incognita was analyzed. This is an effective alternative solution to manage nematode incidence as compared to hazardous chemicals under protected and field cultivation of ginger. In the present study an attempt has been made to isolate, characterize, and identify potential rhizobacteria associated with ginger rhizosphere and endosphere. In total, 169 bacterial isolates were isolated from ginger (Zingiber officinale) rhizosphere and endosphere of 4 different sites of Sirmaur district, screened out for multifarious PGP traits showing positive results. The combined cluster analysis and 16S rRNA genotypic analysis of selected bacterial isolates revealed that Serratia marcescens FS-23, Pseudochrobacter sp. GS-15, Stonotrophomonas pavanii HER-9, Pseudomonas brassicacearum HER-20 and Serratia marcescens IS-2 exhibited highest PGP traits. All tested bacterial isolates were capable of exerting a significant effect on mortality of juvenile M. incognita ranging upto 40-90% in laboratory experiments. Further a consortium of these screened isolates showed 86.67% reduction in gall formation by M. incognita in lab conditions. The remarkable increase to 93.24% with 138.73q/ha with application of charcoal based bio-formulation of consortium without adding any chemical fertilizer was observed in field trials of Nohradhar of Sirmaur district. An alternative choice as a biocontrol agent as well as for PGP activities, the novel and most robust isolate Serratia marcescens IS-2 had revealed to have a variety of bioactive metabolic products with abilities against nematodes, bacteria, and fungi.

Changes in Soil Nematode and Microbial Community in Cucumber Root-Zone Soil Shaped by Intercropping with Amaranth

Intercropping systems often contribute to soil health management including inhibiting root-knot nematode disease. The main purpose of this study was to investigate the potential effect of the cucumber-amaranth intercropping system on soil biota, specifically the nematode and microbial communities. Furthermore, the cucumber root-nematode disease was also evaluated. The study found significant effects of cultivation systems (cucumber-amaranth intercropping and cucumber monocropping) and growing seasons (winter-spring (WS) and autumn-winter (AW)) on both soil nematode and microbial community structures in cucumber root-zone soil. Intercropping resulted in a decrease in the relative abundance of Meloidogyne spp., which was consistent with the observed alleviation of root-knot nematode disease. Bacterivorous nematodes were dominant in the intercropping system. The microbial biomass and community-level physiological profiles (CLPP) were generally higher in the intercropping system. Beta diversity analysis showed that the composition of microbial communities varied widely among the treatments and growth seasons. These findings suggest that intercropping with amaranth can regulate soil biota, leading to decreased incidence of root-knot nematodes (RKNs) diseases.

Nematode and Coccidia Infections in Singing Birds Kept in Bird Stalls

Singing birds are adored by so many people in the Special Region of Yogyakarta because of their beautiful voices. Even so, these birds have the possibility to carry endoparasitic infections, namely nematode and coccidia. This study was conducted to determine the incidence of nematode and coccidia infection in singing birds traded in bird stalls in the Special Region of Yogyakarta. The singing birds were categorized into five feeding guilds, consisting of 19 herbivores, 19 granivores, 31 omnivores, 20 insectivores, and five carnivores. Thirty-seven birds kept in colony cages (eg. 4-6 birds of the same species in one cage) and 57 birds kept in individual cages were used in this study. Fresh faeces was sampled and transported in ice box to the laboratory for parasitological examination. Whitlock method was used to assess the presence of endoparasites. The incidence of endoparasites infection was analyzed descriptively. The result showed that 5.32% of the birds were infected by nematode and 30% by coccidia. Based on the cage systems, the incidence of nematode infection in the birds kept in the colony cage was 10.8%, whereas those in the individual cage was at the lower level of 1.8%. The incidence of coccidia infection in birds kept in colony and in individual cages was 35% and 26%, respectively. Based on the feeding guild categories, nematode infection was found in herbivores (10.5%), granivores (10.5%), and omnivores (3.2%). The coccidia infection was observed in herbivorous (47.4%), omnivorous (41.9%), granivorous (15.7%), and insectivorous (15%) birds. Maintenance management needs to be considered to prevent and eradicate endoparasites infection in singing birds kept individually or in colonies.

The First Record of Nematodes in Ostriches (Struthio Camelus Linnaeus, 1758) of Uzbekistan

Breeding of ostriches is a recently developed sector of venter production in the Khorezm region of Uzbekistan and it is still a young poultry industry. Ostriches have acclimatized approximately since 2015 in Uzbekistan. From this time and until recently, so little exploration has been performed on ostriches and any parasitic species of ostriches have not been researched in Uzbekistan. The objective of the exploration is to define the first findings of two species of nematodes in ostriches (Struthio Camelus) introduced in the Kushkupir district, the Khorezm region of Uzbekistan. The main target of the exploration was to identify the first findings of some nematodes found in ostriches on the farm called “Ibrat’, ’Ruzmat” located in the Kushkupir district, the Khorezm region, Uzbekistan. We recognized the incidence of nematodes in farmed ostriches during the time of conserving and growing ostriches. A total of 15 ostriches from which 15 ostriches (7 were males and 8 females) were over 3 years old with an average weight of 120 kg in the farm named “Ibrat ’, ’Ruzmat” were selected for the research from September 2021 to February 2022. Fecal samples gathered from the farm were sent to a laboratory named “Preventing the Spread of Termites and Fighting against them” in Khorezm Mamun Academy, Khiva, Uzbekistan. The parasites determined for the first time in farmed ostriches were nematodes including Libyostrongylus douglassii and Libyostrongylus dentatus. Our findings demonstrate a high prevalence of Libyostrongylus spp. in ostriches on a farm located in the Kushkupir district, the Khorezm region, Uzbekistan. Studying ostriches’ nematodes and further developing measures against them is important.

POPULAÇÃO DE NEMATOIDES EM CAFEEIRO ADUBADO COM COMPOSTO ORGÂNICO

INTRODUCTION: The use of organic compost to increase organic matter has been a great ally of the rural producer, since it is a practice of easy access, financially viable and ecologically sustainable. Thus, understanding the influence of organic composts on the incidence of nematodes in the soil, consequently, can help reduce the damage caused by these organisms. OBJECTIVE: Influence of organic compost fertilization on nematode population in soil cultivated with coffee trees. METHODS: A randomized block design was used in the experiment, with five treatments (doses of organic compost, 0, 2.5, 5, 7.5 and 10 t ha-1), divided into four blocks, totaling twenty experimental units. The soils had already been corrected with limestone application at doses of 0, 1, 2, 3, and 4 t ha-1. The dose of organic compost application was inversely proportional to the dose of lime application. RESULTS: The results showed a significant increase in calcium, potassium, base saturation and base sum levels. CONCLUSION: The organic matter content does not interfere in the nematode population.

Plant Parasitic Nematodes Associated with Maple (Acer Caesium) And Poplar (Populous Nigra) In District Swabi

Background: Parasitic nematodes are very destructive to crops, ornamental plants and woody plants as well which cause most severe diseases in plants and feed on the roots of these plants.
 Objective: Main aim of this study is to identify different species of nematodes associated with Maple (Acer caesium) and Poplar (populous nigra) trees at district Swabi, Khyber Pakhtunkhwa, Pakistan.
 Methodology: Some Maple and Poplar growing areas of District Swabi were surveyed during the year 2019, for the occurrence and incidence of parasitic nematodes. Soil samples collected from different localities were analyzed for the nematodes. Plant-parasitic nematodes were extracted from soil by Cobb methods, and identified the species after fixation.
 Result: Maximum analyzed simples were infected and among all localities seven different species of nematodes has been recorded. Maximum infection was recorded in Zaida, Manki and Anbar. Following nematodes were found named Paratylenchus Larvae, Aphelenchus avenae, helicotylenchus dihystera, Tylenchus, Trichodorous and Meloidogyne incognita. Ratio of occurrence among all different varieties of nematodes Meloidogyne incognita species shows most abundance in two localities Lahor and Zaida.
 Conclusion: The results clearly indicate the fact that studied area is mostly infected with different types of parasitic nematodes species which highly affect the Maple (Acer caesium) and Poplar (populous nigra) plants.

Nematicidal potential of plant growth-promoting rhizobacteria against Meloidogyne incognita infesting tomato under protected cultivation

BackgroundIn the protected cultivation of tomato (Solanum lycopersicum L.) crop, the severity of root-knot nematode, Meloidogyne incognita, incidence is alarming nowadays. To combat this, growers usually prefer using synthetic chemical pesticides, which in turn results in harming non-target beneficial microbes present in the soil micro-flora and indirectly toxic to human health. Therefore, attempts were made to find out the nematicidal potential of plant growth-promoting rhizobacteria (PGPR) against M. incognita, which could be used as an alternative solution to manage M. incognita incidence under protected cultivation.ResultsNematicidal potential of three PGPR isolates and their consortium against M. incognita under laboratory, pots, and field experiments was studied. Juvenile mortality of 91.67% was recorded at 100% consortium, followed by 73.33–81.33% by individual isolates. Similarly, hatching inhibition of 84.26% was recorded at 100% PGPR consortium followed by 78.48–83.21% in individual isolates after 96 h. of incubation. In the pots’ study, soil drenched with PGPR isolates consortium, followed by Bacillus subtilis DTBS 5, Pantoea agglomerans, and Bacillus amyloliquefaciens DSBA 11 recorded significant reductions in the nematode incidence. Whereas in the field study, PGPR isolates applied as soil drenching also significantly reduced nematode’s incidence in consortium, followed by B. subtilis DTBS 5 and B. amyloliquefaciens DSBA 11-treated soil in both field experiments. On an average, the plant growth promotion and fruit yield were enhanced than untreated control and PGPR isolates applied as soil drenching gave a significant result than bare root dip treatment.ConclusionsPGPR isolates, B. amyloliquefaciens DSBA 11, B. subtilis DTBS 5, and P. agglomerans, were found to be effective against M. incognita. This finding can be incorporated into the nematode management strategy in tomato crop grown under protected cultivation. Further to enhance the biocontrol efficacy of these PGPR isolates, suitable formulations of either individual or consortium need to be done.

Effect of marigold (Tagetes erecta L.) on soil microbial communities in continuously cropped tobacco fields

Root-knot nematode disease is a catastrophic soil-borne disease in tobacco production. The regulation of natural microbial communities is considered a good disease management approach to suppress the incidence of soilborne diseases. In this study, the effects of tobacco (Nicotiana tabacum L.)-marigold (Tagetes erecta L.) rotation on the diversity and structure of soil microbial communities in continuously cropped tobacco fields were analyzed to manage this devastating pathogen. The results showed that the soil bacterial OTUs increased after marigold rotation and that the bacterial Shannon, ACE, Chao1 index, and fungal Shannon index were higher in the tobacco-marigold rotation fields than in the continuously cropped tobacco fields by 3.98%, 10.37%, 5.46%, and 3.43%, respectively. After marigold rotation, the relative abundances of Actinobacteria, Acidobacteria, and Ascomycota increased by 28.62%, 107.50%, and 57.44%, respectively, and the proportion of beneficial bacterial genera such as Nocardioides, Gemmatimonas, and Bradyrhizobium increased. In addition, our results also showed that rotation of marigold could effectively reduce the incidence of root-knot nematodes in the next crop of tobacco. These results indicate that marigold rotation had a positive effect on the soil microecological environment of continuously cropped tobacco fields, reducing the obstacles to continuous cropping of tobacco.

Use of RGB images from unmanned aerial vehicle to estimate lettuce growth in root-knot nematode infested soil

Lettuce (Lactuca sativa) is an important horticultural commodity all over the world, and its growth can be affected by root-knot nematodes (Meloidogyne spp.). To keep track of plant behaviors, growers are using new technologies. In this paper, aerial images were obtained using a low-cost unmanned aerial vehicle (UAV) to gather crop information in a short time giving acceptable accuracy for decision-making in the field. Evaluations were done to check the flight height interference in the image's quality for lettuce mapping, and select the best one to estimate the effect of root-knot nematode incidence on lettuce growth. In a field infested with M. incognita, lettuce seedlings were planted in plots treated with bionematicide and control plots. Aerial images were obtained using low-cost UAV in four flight heights performed for five weeks, along with field measurements. Images were processed and used to calculate vegetation indices (VI) and vegetation cover (VC). After lettuce harvesting, nematode eggs were extracted from plants' roots and quantified. Plots treated with bionematicide showed no difference from the control plots in eggs number and lettuce growth. Differences in VI values between the flight heights were not consistent, suggesting that VI values could be affected by the lack of luminosity calibration in each flight condition. VC values calculated from field data presented strong positive correlations with VI and VC values from UAV image data, indicating that RGB images obtained by UAV can be used in the detection of diseases that affect plant growth, as well as following up harvesting time.

Antimicrobial peptides producing native Bacillus spp. for the management of root-knot nematode Meloidogyne incognita infecting okra (Abelmoschus esculentus L. Moench)

In the present study, native strains of Bacillus species were isolated, characterized and evaluated for their biocontrol efficacy in laboratory, pot and field conditions to combat Meloidogyne incognita incidence in okra (Abelmoschus esculentus L. Moench). Based on the laboratory results, two Bacillus spp., Bacillus marisflavi CRB2 and Bacillus subtilis CRB7 were found most effective against M. incognita. We also profiled antimicrobial peptide (AMP) genes associated with this two Bacillus spp. Bacillus marisflavi CRB2 was found to harbour 10 AMP genes whereas, B. subtilis CRB7 had 8 AMP genes with the expression of 3 and 4 genes, respectively at the RNA level. Talc based formulation of B. marisflavi CRB2 and B. subtilis CRB7 were evaluated under pot and field conditions for the management of M. incognita in okra. Bacillus marisflavi CRB2 and B. subtilis CRB7 at dose of 5 g plant−1 were found most effective against M. incognita by reducing the nematode incidence in okra under pot conditions. Further, field application of either Bacillus marisflavi CRB2 and B. subtilis CRB7 as a combination of seed treatment 20 g kg−1 seed + soil application (5 kg ha−1) of enriched vermicompost (2 t ha−1) + soil drenching @ 1% at 30 days interval showed a significant reduction of M. incognita incidence in okra and also increased yield as compared to untreated control. Their bioefficacy was comparable with carbofuran 3G (1 kg a.i. ha−1) treatments. Thus, the native strains B. marisflavi CRB2 and B. subtilis CRB7 having diverse antimicrobial peptide genes can be used as one of the components in the integrated nematode management strategy to combat M. incognita incidence in okra.

Cover Plants-Mediated Suppression of Fusarium Wilt and Root-Knot Incidence of Cucumber is Associated With the Changes of Rhizosphere Fungal Microbiome Structure-Under Plastic Shed System of North China.

Cover crops are known to alleviate the adverse effects of continuous cropping by influencing plant health and changing host fungal-microbiome structures. However, insight into the shift of rhizomicrobiota composition and their effects on plant growth performance and resistance mechanism is still limited under plastic shed cultivation (PSC). Four leafy vegetable rotations namely spinach rotation (SR), non-heading Chinese cabbage rotation (NCCR), coriander rotation (CR), and leafy lettuce rotation (LLR) were used as cover crops in 7-years of continuous cucumber planted soil (CC). Their ecological impacts were studied for plant growth performance, replant diseases incidence rate, and rhizosphere fungal microbiome. Compared to CC, SR showed a highly suppressive effect on fusarium wilt, i.e., by 13.2% in the spring season, while NCCR decreased the root-knot nematode incidence rate by 8.9% in the autumn season. Such protective effects caused a significant increase of shoot and fruit biomass and thus sustained the fruit quality of cucumber. High-throughput sequencing revealed that the CR, SR, and NCCR treatments altered the fungal community composition by increasing the abundance of the beneficial fungal genera, decreasing pathogenic taxa, and fostering the saprotrophic and symbiotic functions. However, the relative abundance of most of the potentially pathogenic fungal genera increased in CC and LLR cropping. There were 8 potential pathogens and 10 beneficial or biocontrol fungi characterized. It was found that Paecilomyces, Chaetomium, Cladorrhinum, Zopfiella, Purpureocillium, and Metarhizium were the putative biocontrol microbes that positively affected plant growth and replanted diseases inhibition. The characterized Fusarium, Dactylonectria, Alternaria, Gibberella, and Aspergillus were the key pathogenic fungal agents found to be negatively associated with plant growth characters, suggesting that rhizomicrobiome may play an important role in the occurrence of disease incidence of cucumber plants. Considering the ecological potential of some cover plants, this study suggested that rotation with spinach, non-heading Chinese cabbage, or coriander can enhance rhizosphere immunity by triggering the development of plant-protective fungal microbiomes under plastic shed cucumber cultivation.

Nitrogen and potassium synergism influences the yield and quality of Dioscorea cayennensis

This study aimed to evaluate yield, quality, nematode incidence, chlorophyll content, and primary foliar macronutrients of yam in response to nitrogen and potassium fertilization. A complete randomized block design was used in a factorial scheme (5 x 5), with five nitrogen (0; 60; 120; 180 and 240 kg ha-1 of N) and five potassium doses (0; 60; 120; 180 and 240 kg ha-1 of K2O), with four replicates. The mass, total and commercial productivity of tubers, starch content, ash, leaf N, P, and K content, chlorophyll, and nematode incidence were evaluated. The average mass of tubers obtained was 1.935 kg with doses of 133 kg ha-1 of N and 105 kg ha-1 of K2O. The dose of 178 kg ha-1 of N promoted maximum total tuber productivity (22.56 t ha-1). The doses of 132 kg ha-1 of N and 118 kg ha-1 of K2O resulted in maximum productivity of commercial tubers with 20.35 t ha-1. Leaf N and K, starch, and ash contents were within the standards for yam. The incidence of Meloidogyne, Scutellonema, and Pratylenchus reduced with the increasing simple effect doses of N and K2O. The maximum chlorophyll content was obtained at the dose of 240 kg ha-1 of N. The nitrogen and potassium interaction, despite the antagonistic effects on the accumulation of foliar P and starch, increased the productivity and average mass of commercial tubers, consequently ensuring the profitability of yam cultivation.

Diversity of nematodes on banana (Musa spp.) in Kenya linked to altitude and with a focus on the pathogenicity of Pratylenchus goodeyi

Summary Bananas (Musa spp.) are considered the most important fruit crop in Kenya, grown mostly by smallholder farmers. However, in the past two decades production has declined and has largely been attributed to plant pathogens, including plant-parasitic nematodes. To assess the understanding and awareness that banana farmers have of nematodes, a survey was conducted. The incidence, abundance and distribution of nematodes in relation to altitude were determined for different banana types on 180 farms and the pathogenicity of Pratylenchus goodeyi, originating from three different altitudinal locations, was compared on two banana cultivars. Just 2.3% of farmers were aware of nematode damage and symptoms, none of whom applied any management measures. The highest abundance of nematodes was recorded at an altitude range of 1601-2000 m a.s.l., with Pratylenchus, Meloidogyne and Helicotylenchus being the predominant genera. Across all altitudinal locations, cooking banana had higher densities of nematodes than dessert bananas. In pots, P. goodeyi populations from Embu (1300 m a.s.l.) appeared more aggressive and with higher levels of multiplication than the population from Oyugis (1100 m a.s.l.). Cooking banana (‘Ng’ombe’) was more susceptible than dessert banana (‘Sukari Ndizi’). Nematode damage is more prominent in areas at higher altitude and on cooking banana cultivars. The findings provide key information in guiding informed and suitable management decision thresholds in relation to potential climate change.

Nematode pests of some major cereals in Nigeria: Need for integration of morphological/morphometrical, biochemical, and molecular diagnostic approaches for accurate identification

AbstractPlant‐parasitic nematodes pose a major threat to crop production in Nigeria. Comprehensive data on yield losses for most cereal crops are not readily available. Research on maize (Zea mays), rice (Oryza sativa), and sorghum (Sorghum bicolor) has shown an 18%–67% reduction in yield linked to the destructiveness of parasitic nematodes, particularly root‐knot and root‐lesion nematodes. Continuous monoculture and a conservative approach to agriculture increase the incidence and population density of nematodes, leading to higher levels of damage and losses in most cultivated cereal crops. These losses affect the food security of the growing population of Nigeria and many African countries that are heavily dependent on cereals. The accurate identification of nematodes is fundamental for effective management strategies. Nematode taxonomy based on morphology has been difficult due to intraspecific character variations coupled with the limited expertise of indigenous nematologists. Biochemical and molecular marker‐based tools and approaches have allowed efficient diagnosis of most nematode species affecting cereal production globally. These approaches have proved useful due to their practicality, rapidness, accuracy, and cost‐effectiveness. This review describes the important economic effects of these parasitic nematodes on cereal production and highlights the need for integrative approaches to taxonomy for accurate species identification that will improve nematode diagnosis, thereby contributing to the increase of food production in Nigeria.

Incidence of plant-parasitic nematodes in perilla in Korea

Incidence of plant-parasitic nematodes in perilla in Korea

Incidence of Plant-Destructive Nematodes and Associated Damages on Yams Grown in Nasarawa State, North-Central Nigeria

Plant-parasitic nematodes (PPNs) are a major risk to yam (<i>Dioscorea</i> spp.) production in Nigeria. With the aim of establishing plant-parasitic nematode genera associated with yam tubers in Nasarawa State in order to engender sustainable management options and mitigation policies for their control, surveys were conducted in the main yam-producing local government areas (LGAs) of Nasarawa. A total of 54 yam farms were surveyed for PPNs and their associated damage on yam using multi-stage sampling technique. Three communities each, in Lafia, Keana, Kokona, Awe, Obi and Doma LGAs were assessed for the incidence of PPNs and their associated damages on yam. A total of 54 farmers’ fields and 60 yam tubers were assessed in the study. The survey revealed that the eleven PPNs genera were recovered from the soil and tubers of infected yam included Pratylenchus, Hoplolaimus, Helicotylenchus, Criconema, Meloidogyne, Rotylenchus, Scutellonema, Xiphenema, Tylenchulus, Trichodorus and Rotylenchus. Meloidogyne (75.29%, Scutellonema (57.20) and Pratylenchus (44.55%), in order of descending ranking, had the highest incidences across the six LGAs. The destructive activities of these nematodes lead to in unattractive, verrucose or knobby appearances on infected yam tubers, thereby resulting in low to extremely low tuber quality of marketable yams in Nasarawa State.

Bio-management of root knot nematode (Meloidogyne incognita) in tuberose (Polianthes tuberose L.)

The present study on assessment of nematode management in tuberose was conducted by ICAR- Krishi Vigyan Kendra, Madurai during 2014 - 15 and 2015 - 16 at five identified farmers fields in Alanganallur block of Madurai district for an area of 2 ha. The present bio-management was conducted with variety Prajwal. There were four technological options were included in the present assessment such as bulbs were treated with Trichoderma viride + Pseudomonas fluorescens @ 20 g/kg and carbofuran @ 2.5 kg/ha were applied in the field (TO1), bulbs were treated Purpureocillium lilacinum @ 20 g/kg of bulb (TO2) and soil application @ 5 kg/ha and basamid @ 100 g per bed were applied in the each bed and covered with polythene mulch (TO3) and the farmer practices (TO4), application of neem cake @ 250 kg/ha as basal application at the time of last ploughing and indiscriminate application of fertilizers and pesticides spraying were imposed for the present experiment. The present study results revealed that bulbs were treated Purpureocillium lilacinum @ 20 g/kg of bulb (TO2) recorded the minimum days taken for flowering (134.15 days) and farmers practices observed the longest days taken for flowering (147.47 days). TO2 recorded the highest values in vegetative and flowering traits such as plant height (116.24 cm), number of leaves per plant (241.05), spike length (93.50 cm), number of florets per spike (41.80) and floret weight (1.52 g) whereas the farmers practices registered the lowest values in all the vegetative and flowers traits (101.26 cm; 228.14; 88.25 cm; 35.50; 1.09 g). Regards yield characters, TO2 recorded the highest yield per ha (11.18 t/ha) and the lowest yield was noticed in farmer practices (7.75 t/ha). In the case of nematode incidence, the lowest incidence was recorded in TO2 (demonstrated plot) of 10.0 per cent whereas the highest incidence was registered in farmers practices (21.0%). In the case of economic traits, TO2 registered the highest net profit of Rs. 5,10,120 with the B:C ratio of 2.55 and the lowest net profit (Rs. 2,79,250) and B:C ratio (1.64) was noticed in farmers practices.

Phytophagous nematodes in cereal fields in Niğde Province, Turkey

This study evaluated the occurrence and incidence of phytophagous nematodes and identified the cereal cyst nematode species by morphological and molecular tools in the main cereal-growing areas in Nigde in 2018-2019. Phytophagous nematodes within twelve genera were detected in 95% of soil samples. The most common phytophagous nematodes in cereal soil were in the genera Heterodera, Ditylenchus , Merlinius , Pratylenchus , Aphelenchus , Aphelenchoides , Tylenchus , Helicotylenchus , Trophurus , Pratylenchoides , Filenchus and Xiphinema (in decreasing order of incidence). In particular, 75% of the soil samples from surveyed fields were infested with the cereal cyst nematodes (Heterodera spp.). Morphological characteristics of cysts and second-stage juveniles were calculated within the expected ranges for Heterodera filipjevi (Madzhidov, 1981) Stelter, 1984, however, two populations from Camardi was determined as Heterodera latipons Franklin, 1969 (Tylenchida: Heteroderidae). Intraspecific variation was not observed within the populations of H. filipjevi which could be in the same genotypic group. In addition to the high incidence of these Heterodera spp., intensive cereal cropping systems with/without non-cereal rotations in wheat production areas of Nigde also resulted in high incidence of root lesion nematode, Pratylenchus species.

Occurrence of plant-parasitic nematodes on enset (Ensete ventricosum) in Ethiopia with focus on Pratylenchus goodeyi as a key species of the crop

Summary Enset (Ensete ventricosum) is an important starch staple crop, cultivated primarily in south and southwestern Ethiopia. Enset is the main crop of a sustainable indigenous African system that ensures food security in a country that is food deficient. Related to the banana family, enset is similarly affected by plant-parasitic nematodes. Plant-parasitic nematodes impose a huge constraint on agriculture. The distribution, population density and incidence of plant-parasitic nematodes of enset was determined during August 2018. A total of 308 fields were sampled from major enset-growing zones of Ethiopia. Eleven plant-parasitic nematode taxa were identified, with Pratylenchus (lesion nematode) being the most prominent genus present with a prominence value of 1460. It was present in each sample, with a highest mean population density per growing zone of 16 050 (10 g root)−1, although densities as high as 25 000 were observed in fields at higher altitudes in Guraghe (2200-3000 m a.s.l.). This lesion nematode is found in abundance in the cooler mountainous regions. Visible damage on the roots and corms was manifested as dark purple lesions. Using a combination of morphometric and molecular data, all populations were identified as P. goodeyi and similar to populations from Kenya, Uganda and Spain (Tenerife). Differences in population densities amongst cultivars indicate possible resistance of enset to P. goodeyi.