Prevalence, incidence and molecular identification of root-knot nematodes of tomato in Pakistan

Tomato is a widely grown vegetable in Pakistan. However, its production is severely constrained by root knot nematodes (RKNs). Accurate identification of RKNs is essential for an appropriate control program. The current study evaluated the prevalence, incidence and diversity of RKNs of tomato crops grown in the Khyber Pakhtunkhwa Province and their identification using molecular tools. A field survey, including 30 commercial tomato fields, was conducted in ten major tomato growing areas of Swat and Malakand divisions during spring 2010. The overall prevalence and incidence in the study area was 83.3 and 52.0%, respectively. Three species of RKNs, Meloidogyne arenaria, M. incognita and M. javanica were found alone or in mixed populations. Disease incidence ranged from 10% in Malakandher to 100% and 90 to 100% in Jabban and Malakand, respectively. The greatest galling index (GI) (5.0) and egg mass index (EMI) (5.0) was recorded in samples from Jabban, whereas the lowest GI and EMI were recorded in samples from Malakandher and Peshawar. The population density of RKNs was highest in roots (633.0 eggs and second-stage juveniles) and soil (533.0 eggs and second-stage juveniles) samples of Jabban. DNA amplification with rDNA (D2A-D3B) and (194 to 195) primers amplified 750 and 720 bp products for M. arenaria, M. incognita and M. javanica, respectively. Amplification with sequence characterized amplified regions (SCAR) primers produced characteristic products of 420 bp for M. arenaria (Far/Rar), 1200 bp for M. incognita (Finc/Rinc), and 670 bp for M. javanica (Fjav/Rjav). DNA amplification of mtDNA with C2F3/1108 primers yielded a 1700 bp size product for all three species of RKNs in comparison with 520 and 750 bp for M. chitwoodi and enterolobii, respectively, which were utilized as control. Sequencing the 28S rDNA product generated with the D2A-D3B primers did not differentiate among the three Meloidogyne spp. from the study area.Key words: Meloidogyne, species identification, perineal pattern, sequence characterized amplified regions (SCAR) primers

Control of Southern root knot nematode Meloidogyne incognita (Kofoid and White) Chitwood on tomato using green manure of Fumaria parviflora Lam (Fumariaceae)

Extracts of the plant Fumaria parviflora have demonstrated nematicidal properties and it is a potential novel control agent against plant parasitic nematodes. In this research, we examined the use of F. parviflora, in green house and field experiments, as a green manure against Meloidogyne incognita on tomato. M incognita did not parasitize F. parviflora as shown using a host pathogenicity test with a range of different inoculation rates of the nematode. Applications of F. parviflora 15 days before transplanting at the highest dose of 30 g fresh chopped whole plant material per kg of soil showed the most promising results. The root portion of F. parviflora showed higher nematicidal activity than the tops of the plant. All plant growth parameters studied were significantly promoted by the application of green manure in addition to the toxic effect on M. incognita. These data suggest that F. parviflora could be used alone or as part of an Integrated Pest Management strategy as a novel management tool for M. incognita.This research, part of PhD study by Ishrat Naz, was supported by the Higher Education Commission (HEC5000 Fellowship Program Phase–VI) of Pakistan under the Indigenous scholarship program.Peer reviewe

Cis- and trans-protopinium, a novel nematicide, for the eco-friendly management of root-knot nematodes

Plant-derived nematicides are being increasingly used while select synthetic nematicides are phased out for environmental concerns. This is the first report on the in vitro nematicidal activity of cis- and trans-protopinium isolated from roots of Fumaria parviflora and its in vivo effect on the southern root-knot nematode Meloidogyne incognita. Cis- and trans-protopinium was isolated from the methanolic fraction FM2.1, and its structure elucidated using 13C and 1H nuclear magnetic resonance (NMR). The NMR spectra were characterized using deuterated dimethyl sulfoxide (DMSO) at temperatures of 25 and 80 °C. In an in vitro study, over 120 h of incubation, the area under cumulative percent hatch inhibition and mortality of cis- and trans-protopinium reached 100% at a concentration of 200 μg mL−1. In the greenhouse and field settings, cis- and trans-protopinium was evaluated against M. incognita on tomato at a concentration of 100, 200, and 300 μg mL−1 for two consecutive seasons, that is, spring and autumn, in 2010. At a concentration of 300 μg mL−1 in the greenhouse and field trials during spring and autumn, cis- and trans-protopinium significantly reduced the nematode galling index, the number of females per gram of root, and the reproduction factor, as well as increased plant height, fresh and dry shoot weights, and root length. Therefore, cis- and trans-protopinium can be used as an effective and safe nematicide against M. incognita on tomato in an organic and sustainable agricultural production system. Phytochemicals have various agricultural applications, especially to control economically important nematode pests.The funds provided by the Higher Education Commission of Pakistan (HEC) through indigenous scholarships (Batch-VI) are highly appreciated.Peer reviewe

Sustainable management of the Southern root-knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, by means of amendments of Fumaria parviflora

Greenhouse and field studies were conducted in the spring and autumn of 2010 to test the efficacy of dry amendments of Fumaria parviflora as a form of eco-friendly management of Meloidogyne incognita in tomato. Various preparations of F. parviflora (in the form of dry root, stem, leaf and whole plant powder) at different dose rates (10, 20 and 30 g per kg of soil) significantly reduced levels of M. incognita in the roots of tomato cv . Rio Grande, and promoted plant growth. The root amendments of F. parviflora at the highest application dose (30 g per kg of soil) were the most effective, significantly reducing the number of galls, the galling index, the egg masses per g of the root, and the adult femal es per g of the root. Shoot and root lengths, the fresh and the dry shoot weight, and the number of branches and flowers per plant were improved in greenhouse trials that were conducted in the spring and autumn. Under naturally infested field conditi ons, the root ́s amendment of F. parviflora at the highest application dose was the most effect ive, and reduced the number of galls, the GI, the number of egg masses per g of root, the adult femal es per gof root, and the reproduction factor (Rf). It also promoted plant, health and increased the number of fruits per plant and the fruit weight per plant in the spring and autumn experiment. Dry amendments of F. parviflora have remarkable nematicidal potential and could be used as an effective and environment-friendly management tool against M. incognita as an alternative to chemical control. © 2015 Friends Science Publishers.This research, which forms part of the PhD study by Ishrat Naz, was supported by the Higher Education Commission (HEC) of Pakistan, under the indigenous scholarship programme.Peer reviewe