A Nondestructive Technique for Screening Bean Germ Plasm for Resistance to Meloidogyne incognita

Omwega, C. O.; Thomason, I. J.; Roberts, Philip A.

doi:10.1094/pd-72-0970

Cited by 71 publications

(37 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To assess both egg production and egg hatching, the entire root system was submerged in a 0.1 g l -1 erioglaucine solution for 2 h to stain in blue the gelatinous matrix and facilitate counting of the egg masses (Omwega et al 1988). For assessing the begining of egg hatching, egg masses were handpicked and dispersed in 0.5 % NaOCl solution to estimate the number of days until egg production started and the first empty eggs were observed.…”

Section: Thermal Requirementsmentioning

confidence: 99%

Thermal time requirements of root-knot nematodes on zucchini-squash and population dynamics with associated yield losses on spring and autumn cropping cycles

Vela

Giné²,

López-Gómez³

et al. 2014

Eur J Plant Pathol

View full text Add to dashboard Cite

The present research was undertaken to evaluate the effects of soil temperature on the life cycle of root-knot nematodes (RKN) on zucchini-squash in growth chambers and to assess the relationship between Meloidogyne incognita soil population densities at planting (Pi), its multiplication rate, and crop losses of zucchini in field conditions. Thermal requirements for M. incognita and M. javanica were determined by cultivating zucchini plants in pots inoculated with 200 second stage juveniles (J2) of each Meloidogyne species at constant temperatures of 17, 21, 25, and 28 A degrees C. Number of days from nematode inoculation until appearance of egg laying females and until egg hatching were separately recorded. For life cycle completion, base temperatures (Tb) of 12 A(0)C and 10.8 A(0)C and accumulated degree-days above Tb (S) of 456 and 526, were estimated for M. incognita and M. javanica, respectively. The relationship between fruit weight and M. incognita Pi fits the Seinhorst damage function, but differed accordingly to the cropping season, spring or autumn. Tolerance limits for M. incognita on zucchini were 8.1 J2 per 250 cm(3) of soil in spring and 1.5 in autumn cropping cycles, and the minimum relative yields were 0.61 in spring and 0.69 in autumn. Zucchini-squash was a poorer host for M. incognita in spring than in autumn, since maximum multiplication rates (a) and equilibrium densities (E) were lower in spring (a = 16-96; E = 274-484) than in autumn (a = 270-2307; E = 787-1227).Postprint (published version

show abstract

Section: Thermal Requirementsmentioning

confidence: 99%

Thermal time requirements of root-knot nematodes on zucchini-squash and population dynamics with associated yield losses on spring and autumn cropping cycles

Vela

Giné²,

López-Gómez³

et al. 2014

Eur J Plant Pathol

View full text Add to dashboard Cite

show abstract

“…The plants were irrigated three times per week and given a complete nutritive solution once a week. Eight weeks after inoculation, the plant roots were individually washed with tap-water, and stained with 50 mg L -1 erioglaucine (Omwega et al, 1988) in order to specifically stain the egg masses green. The roots were rinsed and examined under a magnifying glass to calculate the galling index and the number of egg masses per plant.…”

Section: Pot Experiments In Controlled Conditionsmentioning

confidence: 99%

Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

Ibañez

Robertson

Martinez-Lluch

et al. 2014

Span. j. agric. res.

View full text Add to dashboard Cite

The root-knot nematode (RKN) Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks) has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL) were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively). A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker) behaved like ATL while two others (Terrano and DRO 8801) were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL) confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field.

show abstract

“…Plants were harvested at 60 dpi, when completion of the life cycle from J2 to J2 was expected . Tops were cut at ground level and their dry weight determined after desiccation in an oven at 60ºC for 72 h. Roots were washed free of soil, weighed and then stained in a 0.1 g/L erioglaucine solution (Aldrich Chemical Company, Milwaukee, WI, USA) for 2 h (Omwega et al, 1988) to facilitate the EM counting. To determine egg production, all EM/ root system were handpicked, placed into an Eppendorf tube and macerated in a 0.5% NaOCl solution for 10 min (Hussey & Barker, 1973), as described for the inoculum preparation.…”

Section: Post-infection Developmentmentioning

confidence: 99%

Penetration and post-infection development of root-knot nematodes in watermelon

López-Gómez

Verdejo-Lucas

2018

Span. j. agric. res.

View full text Add to dashboard Cite

Meloidogyne javanica has showed less reproductive success than M. incognita in watermelon genotypes. This study was conducted to elucidate the low reproduction of M. javanica in watermelon. The post-infection development of M. javanica in watermelon 'Sugar Baby' was determined at progressively higher initial population (Pi) levels at two time points during the life cycle. Plants were inoculated with 0, 25, 50, 100, 200, and 300 second-stage juveniles (J2)/plant. The increase in Pi was correlated with the penetration rates (R 2 = 0.603, p<0.001) and total numbers of nematodes in the root (R 2 = 0.963, p< 0.001) but there was no correlation between the Pi and the reproduction factor (eggs/plant/Pi). The population in the roots at 26 days post-inoculation (dpi) consisted primarily of thirdstage juveniles (J3) with a small presence of J2 and fourth stages, and egg-laying females. The dominance of the J3, when egg-laying females are expected, point to the malfunction of the feeding sites that failed to support nematode development beyond the J3 stage. The similarities in egg-laying females at 26 and 60 dpi imply the disruption of the life cycle. Watermelon compensated for M. javanica parasitism by increasing vine length (19% to 33%) and dry top weight (40%) in comparison with the non-inoculated plants. The area under the vine length progress curve was significantly larger as the Pi progressively increased (R² = 0.417, p<0.001). Physiological variation was detected between the M. incognita populations. M. arenaria had less ability to invade watermelon roots than did M. incognita and M. javanica.

show abstract

A Nondestructive Technique for Screening Bean Germ Plasm for Resistance to Meloidogyne incognita

Cited by 71 publications

References 0 publications

Thermal time requirements of root-knot nematodes on zucchini-squash and population dynamics with associated yield losses on spring and autumn cropping cycles

Thermal time requirements of root-knot nematodes on zucchini-squash and population dynamics with associated yield losses on spring and autumn cropping cycles

Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

Penetration and post-infection development of root-knot nematodes in watermelon

Contact Info

Product

Resources

About