scholarly journals Infestation of Rice Root-Knot Nematode in Rice Nurseries in Chitwan

1970 ◽  
Vol 10 ◽  
pp. 45-49 ◽  
Author(s):  
N. K. Dangal ◽  
S. M. Shrestha ◽  
D. Sharma Poudyal ◽  
C. Adhikari

A survey was conducted during June-July 2006 in Chitwan to find out the natural infestation of rice root-knot nematode (Meloidogyne graminicola Golden & Brichfield) in rice nurseries. Thirty nurseries were surveyed and 100 seedlings from each nursery were evaluated. Field survey revealed that M. graminicola was widely distributed in most rice growing areas of Chitwan District. Rice root-knot disease was more prevalent in dry bed condition than wet bed. Most of the farmers grew seedlings in upland (dry) soil and there was more rice root-knot disease and second stage juvenile (J2) population in both nursery soil and seedling root. The galled (diseased) seedlings had significantly shorter roots and shoots. Most of the farmers did not know about the nematode problem and did not follow any management practices to control it in nurseries and/or in the main field. This indicated high risk of multiplication of the nematodes and huge loss in rice production. Thus, it is essential to manage M. graminicola in rice nurseries in order to produce healthy seedlings.Key words: Dry bed; Lowland; Meloidogyne graminicola; Upland; Wet bedDOI: 10.3126/njst.v10i0.2822Nepal Journal of Science and Technology Volume 10, 2009 December Page: 45-49  

Nematology ◽  
2012 ◽  
Vol 14 (4) ◽  
pp. 405-415 ◽  
Author(s):  
Ma. Teodora Nadong Cabasan ◽  
Arvind Kumar ◽  
Dirk De Waele

Migration, penetration, development and reproduction of the rice root-knot nematode, Meloidogyne graminicola, in the resistant African rice genotypes TOG5674, TOG5675, CG14 and RAM131, and in the susceptible Asian rice genotypes IR64 and UPLRi-5 were studied and compared. The number of second-stage juveniles (J2) that had migrated horizontally and vertically towards the rhizosphere at 48 h after inoculation was comparable in both resistant and susceptible rice genotypes. Penetration of J2 was significantly lower in the resistant rice genotypes compared with the susceptible rice genotypes at 3 and 7 days after inoculation (DAI). Nematode development in the resistant rice genotypes was slower than in the susceptible rice genotypes. Nematode reproduction was significantly lower in the resistant rice genotypes, which supported fewer eggs per g of roots and eggs per female. A significantly higher percentage of egg-laying females was found in the susceptible rice genotypes. Mature females that had developed in the resistant rice genotypes were significantly smaller than the ones in the susceptible rice genotypes. The resistant rice genotypes had significantly fewer galls than the susceptible rice genotypes.


Plant Disease ◽  
2002 ◽  
Vol 86 (12) ◽  
pp. 1339-1344 ◽  
Author(s):  
E. B. Gergon ◽  
S. A. Miller ◽  
J. M. Halbrendt ◽  
R. G. Davide

Rice root-knot nematode, Meloidogyne graminicola, infects all commercially grown onion cultivars in rice-onion cropping systems in the Philippines, but its economic importance has not been established. The effects of different preplant population levels (Pi) of M. graminicolaon Yellow Granex onion in pots and of different percentages of galled roots in a naturally infested field were evaluated. Leaf weight and root length of ‘Yellow Granex 429’ seedlings decreased with increasing Pi, while low Pi mildly stimulated plant height at the vegetative growth stage. Age of transplant and Pi influenced growth and yield of onion at maturity. Onion yield and root and leaf weights decreased as the age of the transplants increased. Growth and yield decreased with increased Pi. Bulb weight was reduced by 7 to 82% and diameter by 10 to 62% when plants were inoculated with 50 to 10,000 second-stage juveniles. Onion bulbs from the field were reduced by 16, 32, and 35% in weight and by 6, 17, and 18% in diameter when the percentage of roots galled was 10, 50, and 100%, respectively. Management of M. graminicolapopulations at the start of the growing season must be part of onion culture in rice-onion systems to reduce onion yield losses and to prevent economic loss.


1970 ◽  
Vol 9 ◽  
pp. 21-27 ◽  
Author(s):  
Nabin Kumar Dangal ◽  
D. Sharma Poudyal ◽  
S. M. Shrestha ◽  
C. Adhikari ◽  
J. M. Duxbury ◽  
...  

Pot experiment was conducted during July-September 2006 to evaluate some organic amendments such as sesame (Sesamum indicum) biomass, buckwheat (Fagopyrum esculentum) biomass, neem (Azadirachta indica) leaves, chinaberry (Melia azedarch) leaves and chicken manure @ 1, 2 and 3 t ha-1 each against the rice root-knot nematode (Meloidogyne graminicola Golden & Birchfield) in direct seeded rice. The treatments were replicated five times in a randomized complete block design. The number of second stage juveniles (J2) of M. graminicola was significantly low in chicken manure @ 3 t ha-1. The root knot severity index was significantly low in sesame @ 3 t ha-1, chinaberry @ 3, 2 or 1 t ha-1, neem @ 3 t ha-1 and chicken manure @ 2 or 3 t ha-1 amended soil but root lesion severity index was lower only in chicken manure @ 2 t ha-1 treated plots. The fresh shoot weight and length were significantly high in chicken manure amendment @ 2 or 3 t ha-1 at 45th day after seeding. However, the fresh root weight, length, number of leaves and number of J2 recovered from the roots were non-significant. Key words: biomass; juveniles; Meloidogyne graminicola; root-knot severity index; root lesion severity index DOI: 10.3126/njst.v9i0.3160 Nepal Journal of Science and Technology 9 (2008) 21-27


Nematology ◽  
2008 ◽  
Vol 10 (4) ◽  
pp. 525-538 ◽  
Author(s):  
Maria Jose Charchar ◽  
Jonathan Eisenback ◽  
Maria Esther Boiteux ◽  
João Charchar

AbstractMeloidogyne phaseoli n. sp. is described and illustrated from specimens parasitising bean cv. Carioca in Brasilia, Brazil. The perineal pattern of the female is rounded to oval-shaped with a dorsal arch that is flattened to moderately high and squarish, sometimes with rounded shoulders. The striae are moderately spaced and often distinctly forked in the lateral field. The female stylet is 14-19 μm long and has broad, distinctly set-off knobs and several small, rounded projections on the shaft. The excretory pore opens 34-82 μm from the head near the level of metacorpus. Males are 999-2105 μm in length and have a high, wide head cap that slopes posteriorly. The labial disc and medial lips are partially fused to form an elongated lip structure. The robust stylet is 20-26 μm long and has wide knobs that are distinctly set-off from the shaft which is marked by several small, round projections. Mean second-stage juvenile length is 464 μm. The head region is not annulated and the large labial disc and crescent-shaped medial lips are fused to form a dumbbell-shaped head cap. The stylet is 10.5-12 μm long and has rounded, posteriorly sloping knobs. The slender tail, 46-64 μm long, has large irregular-sized annules in the posterior region and a slightly rounded tip. The hyaline tail terminus is long, 10.5-19.3 μm. The esterase isozyme is a unique E3 phenotype having one weak and two strong bands. Tomato, tobacco, bean and pea are good hosts, corn is a very poor host, whilst pepper, watermelon, peanut, cotton and soybean are non-hosts.


2020 ◽  
Vol 3 (2) ◽  
pp. 21-31
Author(s):  
Sudeep Subedi ◽  
Bihani Thapa ◽  
Jiban Shrestha

Root-knot nematode (RKN) Meloidogyne incognita stands out among the most harmful polyphagous endoparasite causing serious harm to plants, and distributed all over the globe. RKN causes reduced growth, quality and yield along with reduced resistance of the host against biotic and abiotic stresses. Infective second stage juvenile enters host roots with the help of the stylet and becomes sedentary getting into the vascular cylinder. Dramatic changes occur in host cells, making a specialized feeding site, induced by the secretion of effector protein by RKN. M. incognita can be controlled by nematicides, biocontrol agents, botanicals essential oils and growing resistant cultivars. Nematicides are no longer allowed to use in many parts of the world because of environmental hazards and toxicity to humans and other organisms. Researchers are concentrating on searching suitable alternatives to nematicides for effective management of M. incognita. This review mainly tries to explain the biology of M. incognita and different management options recommended in recent years. However, an effective and economical management of M. incognita remains an immense challenge.


2015 ◽  
Vol 9 (16) ◽  
pp. 1128-1131 ◽  
Author(s):  
Ravindra H ◽  
Sehgal Mukesh ◽  
B Narasimhamurthy H ◽  
S Imran Khan H ◽  
A Shruthi S

Nematology ◽  
2000 ◽  
Vol 2 (2) ◽  
pp. 191-199 ◽  
Author(s):  
Hari Gaur ◽  
Jack Beane ◽  
Roland Perry

Abstract The root-knot nematode, Meloidogyne triticoryzae, produces three kinds of unhatched second stage juveniles (J2): i) those that hatch freely in water, ii) those that require stimulus from rice root diffusate (RRD), and iii) those that do not hatch even in the presence of RRD. The proportion of these three types varies with generation, with the final generation produced on senescing plants having a large proportion of unhatched J2 of the third type, which is likely to equate with diapause. Dilution of RRD reduced its hatching activity and there is no evidence of the presence of inhibitors in the diffusate. The hatching response of M. triticoryzae may be modified additionally by the growing conditions: submergence of infected plants may have delayed hatch, possibly by causing anoxybiosis in unhatched J2, and thereby delayed the appearance of the second and third generations of the nematodes. Le nématode Meloidogyne triticoryzae produit trois types de juvéniles de 2ème stade (J2) non encore éclos: i) ceux qui éclosent d’eux-même dans l’eau; ii) ceux qui requièrent le stimulus produit par le diffusat radiculaire de riz (RRD); enfin iii) ceux qui n’éclosent pas même en présence de RRD. La proportion de ces trois types varie avec la génération du nématode, la dernière génération, produite sur un hôte sénescent, contenant une grande proportion de J2 non éclos de type 3, ce fait représentant l’équivalent d’une diapause. La dilution du RRD diminue l’éclosion et aucune évidence d’inhibiteurs n’a été relevée dans le diffusat. Chez M. triticoryzae l’éclosion peut de plus être modifiée par les conditions de croissance de l’hôte; ainsi la submersion des plants infestés peut retarder l’éclosion, l’anoxybiose ainsi induite affectant vraisemblablement les J2 non éclos et retardant de ce fait l’apparition des deuxième et troisième générations du nématode.


Nematology ◽  
2011 ◽  
Vol 13 (5) ◽  
pp. 509-520 ◽  
Author(s):  
Tushar K. Dutta ◽  
Stephen J. Powers ◽  
Brian R. Kerry ◽  
Hari S. Gaur ◽  
Rosane H.C. Curtis

AbstractThe rice root-knot nematode Meloidogyne graminicola normally infects rice, wheat and several other graminaceous plants. Meloidogyne incognita is a serious pest of dicotyledonous crops, although it can infect and reproduce on some cereals. This paper demonstrates and compares host recognition, development and reproduction of these two species of root-knot nematodes on rice and tomato plants. Attraction bioassays in pluronic gel clearly showed that M. incognita preferred tomato roots to rice or mustard roots, whilst M. graminicola was more attracted towards rice compared with tomato or mustard roots. Based on the attraction data from this study, it can be hypothesised that either: i) the blend of attractants and repellents are different in good and poor hosts; or ii) relatively long-range attractants, together with shorter-range repellents, might affect nematode movement patterns. Some host specific attractants might also be involved. Meloidogyne incognita was able to invade and develop to adult female but did not produce eggs in rice roots. By contrast, M. graminicola developed and reproduced faster on both rice and tomato plants compared with M. incognita. Nevertheless, second-stage juveniles of both these root-knot nematodes showed a similar pattern of distribution inside the roots, preferring to accumulate at the root tips of rice or in the vascular cylinder and cortical region of tomato.


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