Spatial and temporal dynamics of Meloidogyne minor on creeping bentgrass in golf greens

Abstract

Meloidogyne minor, first reported on potatoes in the Netherlands in 2004, is an emerging nematode pest in Europe. It damages turfgrass, particularly creeping bentgrass (Agrostis stolonifera) grown on sandy soils such as those of golf greens. However, little is known of the nematode's life history and pathology. In this study, the spatial and temporal distribution of M. minor on a creeping bentgrass green in Ireland was determined over a 15 month period. Cores were taken on transects across yellowing patches of grass caused by nematode damage. Second-stage juveniles (J2) were absent from the soil from November to February, when soil temperatures were below 10°C. Both galls and egg masses were present throughout the year but were more abundant in late summer and early autumn. More J2, galls and egg masses were present in the top 10 cm of soil than at a depth of 11-20 cm. The nematode population tended to decrease as distance from the centre of the yellow patches increased. The diameter of visual symptoms (yellow patches) was also recorded over the 15 months. The mean diameter of five sampled patches increased from 23Á7 cm in June 2003 to 45Á2 cm in August 2004. There were 158-193 galls per 100 cm 3 soil at the margin of the visible infested area, indicating that this could be the threshold level for visible symptoms.

Leachates from plants recently infected by root-feeding nematodes cause increased biomass allocation to roots in neighbouring plants

“…Four ml of the inoculum of nematodes in tap water with a concentration of about 350 J2 individuals/ml was added into a hole at 0.5 cm distance from the stem and 2 cm deep below the soil surface of the treatment plants to standardize the inoculation procedure and maximize the infection rate. There were approximately 1400 juveniles per treatment plant, which is more than the maximum density (374 J2 per 100 cm 3 soil) of J2 found in roots of infected A. stolonifera in the field 35 . We used a higher density to compensate for anticipated losses of nematodes after inoculation because of establishment failure.…”

“…We used creeping bentgrass, Agrostis stolonifera , and the root-feeding nematode species Meloidogyne minor as our model system. M. minor is known to cause so-called yellow patch disease in creeping bentgrass 33 – 35 . Creeping bentgrass seeds were obtained from a commercial supplier (Cruydt-Hoeck, Netherlands).…”

A molecular beacon real-time polymerase chain reaction assay for the identification of M. chitwoodi, M. fallax, and M. minor

“…The potato tubers exhibited pimple-like galling similar to the symptoms caused by M. chitwoodi and M. fallax. Meloidogyne minor was subsequently found on golf courses in the Netherlands, Belgium, United Kingdom, and Ireland (Vandenbossche et al, 2011;Morris et al, 2013). Interestingly, M. minor infections did not significantly impact tuber yield or quality in two potato cultivars (cvs Asteŕix and Markies) in field plots in the Netherlands (Thoden et al, 2012).…”

“…Recently M. minor was reported on turf grass in the USA (McClure et al, 2012;Nischwitz et al, 2013). It is possible that this nematode could be accidentally transmitted from golf courses to arable land via contaminated sports shoes or equipment (Morris et al, 2011;Morris et al, 2013). With the potential for M. minor to spread and cause damage to potatoes, it is prudent to monitor for M. minor to help mitigate the risk it poses to USA agriculture.…”