The tomato Mi-1.2 gene confers resistance against both root-knot nematodes and the potato aphid. Plants are resistant to nematodes early in root development. However, plants as old as 4 weeks are susceptible to aphid infestation. We monitored Mi-1.2 expression at the transcriptional level in resistant (Mi/Mi) and susceptible (mi/mi) tomato cultivars by means of RT-PCR. Mi-1.2 transcripts accumu...

A full-length cDNA, MIC-3, has been identified from a lambda ZAPII cDNA library constructed from the mRNA of nematode-resistant cotton (Gossypium hirsutum L.) roots after infection with root-knot nematode (Meloidogyne incognita). The putative open reading frame of MIC-3 encoded a protein of 141 amino acids with a calculated molecular mass of 15.3 kDa. Seven alternative polyadenylation sites hav...

Twelve soil drenches over a period of 30 days with DBCP concentrations of 40 microg/ml did not completely prevent infection of tomato plants by root-knot nematode juveniles. Repeated DBCP drenches of 40 microg/ml halted gall development during the drenches, but 10 days after drenching was discontinued galls were apparent. DBCP drenches at 200 microg/ml prevented tomato root development, and 40 ...

Root-knot nematode is one of the major pest vegetable crops that produces root galls in infected roots, seriously reducing farmer’s produce. According to statistics, phyto-parasitic nematodes affect 12.3% world’s each year, resulting yield losses. Most common species root-knot have been reported be vulnerable cucumber and they can reduce productivity by up 60% protected commercial farming. Till...

Experiments were conducted in the greenhouse to assess root galling and egg production of three root-knot nematode species, Meloidogyne arenaria, M. incognita, and M. javanica, on several weeds common to Florida agricultural land. Weeds evaluated were Amaranthus retroflexus (redroot pigweed), Cyperus esculentus (yellow nutsedge), Eleusine indica (goosegrass), Portulaca oleracea (common purslane...

Host-parasite relationships of Meloidogyne incognita acrita and Pratylenchus penetrans were compared on three closely related cultivars of tomato: 'Nemared', resistant to root-knot nematodes; 'Hawaii 7153', moderately resistant; and 'B-5', susceptible. Root-knot nematode larvae induced typical galls on the roots of B-5; larvae that entered Nemared were walled-off by necrotic cells; both reactio...

Ten cultivars and 13 germplasms of white clover (Trifolium repens) were evaluated in the greenhouse for resistance to the southern root-knot nematode, Meloidogyne incognita race 4. One hundred plants of each cultivar or germplasm were rated for percentage of the root system galled (PRSG) at 60 days after inoculation with root-knot nematode eggs. Tillman (9%) and SRVR (19%) had the highest perce...