⚙
AI-generated deep summary
by claude@2026-06, 2026-06-24
· read from full text
ⓘ
The paper studied 14 Meloidogyne root-knot nematode populations collected across California fields to test their ability to complete life cycles and reproduce on Mi-1 tomato cultivars, including the processing tomato ‘Celebrity’. Using greenhouse assessments, the authors found all populations could develop and reproduce on Mi-1, with no observed differences in gall index among populations but significant quantitative variation in reproduction factor values. They identified a negative correlation between the populations’ latitudes of origin and reproduction factors, suggesting higher aggressiveness in populations from lower latitudes, potentially related to warmer temperatures; a limitation is that aggressiveness was evaluated using greenhouse metrics focused on Mi-1-compatible nematodes. The paper does not explicitly discuss endometriosis or adenomyosis; it was included in the corpus via a keyword match in the upstream search index.
Abstract
Tomato is a food crop of global importance, with a large proportion of processing tomatoes produced in California. One of the main problems plaguing tomato production is infection by populations of root-knot nematodes (RKNs; Meloidogyne spp.) that can evade or suppress (‘break’) resistance mediated by the Mi-1 gene, which has been introgressed into most processing tomato cultivars. In this study, we evaluate fourteen Meloidogyne spp. populations collected from fields across the state of California that can complete their life cycle on Mi-1 tomato cultivars. One of these populations was identified as M. javanica and the others as M. incognita . All RKN populations developed and reproduced on Mi-1 tomato cultivar ‘Celebrity’. Although we did not observe differences in gall index among populations when studied together in greenhouse conditions, significant quantitative variation in reproduction factor values was apparent among them. Several pathogens and parasites display geographical gradients in aggressiveness and we identified a negative correlation between populations’ latitudes-of-origin and reproduction factors. This suggests that populations of these thermophilic RKN species from lower latitudes tended to have evolved higher levels of aggressiveness on Mi-1 tomato, which may be linked to warmer temperatures throughout the year. Finally, populations with relatively low reproduction factor values still showed significant differences in the phenotypes of the galls they induced. Our results showed that Meloidogyne populations evolved genetic variation in aggressiveness along a latitudinal gradient in Californian processing tomato agroecosystems, which may have implications for managing these important crop pests.
Full text
1,828 characters
· extracted from
oa-doi-fallback
· click to expand
Abstract
Tomato is a food crop of global importance, with a large proportion of processing tomatoes produced in California. One of the main problems plaguing tomato production is infection by populations of root-knot nematodes (RKNs; Meloidogyne spp.) that can evade or suppress (‘break’) resistance mediated by the Mi-1 gene, which has been introgressed into most processing tomato cultivars. In this study, we evaluate fourteen Meloidogyne spp. populations collected from fields across the state of California that can complete their life cycle on Mi-1 tomato cultivars. One of these populations was identified as M. javanica and the others as M. incognita. All RKN populations developed and reproduced on Mi-1 tomato cultivar ‘Celebrity’. Although we did not observe differences in gall index among populations when studied together in greenhouse conditions, significant quantitative variation in reproduction factor values was apparent among them. Several pathogens and parasites display geographical gradients in aggressiveness and we identified a negative correlation between populations’ latitudes-of-origin and reproduction factors. This suggests that populations of these thermophilic RKN species from lower latitudes tended to have evolved higher levels of aggressiveness on Mi-1 tomato, which may be linked to warmer temperatures throughout the year. Finally, populations with relatively low reproduction factor values still showed significant differences in the phenotypes of the galls they induced. Our results showed that Meloidogyne populations evolved genetic variation in aggressiveness along a latitudinal gradient in Californian processing tomato agroecosystems, which may have implications for managing these important crop pests.
Competing Interest Statement
The authors have declared no competing interest.
Text is read by the "Ask this paper" AI Q&A widget below.
Extraction quality varies by source — PMC NXML preserves structure
cleanly, OA-HTML may include some navigation residue, and OA-PDF can
have broken hyphenation. The publisher copy
(via DOI)
is the canonical version.