Effects of Soil Textures on Infectivity of Root-Knot Nematodes on Carrot

Abstract

This study was conducted to examine infectivity (penetration and gall and egg-mass formations) of the root-knot nematodes, Meloidogyne incognita and M. hapla, on carrots grown in soil conditions of 5 different soil textures consisting of bed-soil (b) and sand (s) mixtures (b-s mixtures) at the ratios of 10:0, 7:3, 5:5, 3:7, and 0:10. For M. incognita, the nematode penetration rates in b-s of 0:10 (100% sand) were significantly higher than in the other b-s mixtures, more greatly at 2 and 5 days after inoculation than at 10 DAI, while no significant differences in the penetration rates were mostly shown for M. hapla at the above DAI. However, for both nematodes, gall and egg-mass formations were remarkably increased in the b-s mixture of 0:10, compared to the other b-s mixtures, which is coincided with the general aspects of severe nematode infestations in sandy soils. This suggests the increased gall and egg-mass formations of M. incognita should be derived from the increased penetration rates in the sandy soil conditions, which provide a sufficient aeration due to coarse soil nature for the nematodes, leading to their mobility increased for the enhanced root penetration. For M. hapla, it is suggested that the sandy soil conditions affect positively on the healthy plant growth with little accumulation of the inhibitory materials and sufficient aeration, enhancing the nematode growth and feeding activities. All of these aspects provide information reliable for the development screening techniques efficient for the evaluation of the nematode resistance in the breeding programs.

Short Communication: The prevalence and species of root-knot nematode which infect on potato seed in Central Java, Indonesia

“…It was also in line with Archidona-Yuste et al 2018, M. incognita has a high positive correlation with sandy loam soils, whereas it has a negative correlation with silt and clay (Asif et al 2015). Sandy soil texture can facilitate J2 to penetrate the roots, thus the gall and egg mass were significantly increase in this soil type (Kim et al 2017). Furthermore, potato infection caused by Meloidogyne spp.…”

Differential Morphological, Structural and Biological Characteristics of Cysts in Heterodera Species in Korea

“…Lee 74 (for Hg and Hs) and Chinese cabbage cv. Koryeo (for Ht) for 40 days, and the cysts produced in the plants were collected on a 100-mesh screen and crushed with a tweezers to release eggs, from which second-stage juveniles (J2) were hatched by the modified Baermann funnel method (Kim et al, 2017). The J2 were suspended in sterilized distilled water (SDW) to make nematode solution containing 100 J2/ml.…”

“…The fixed specimens were dehydrated in a series of ethanol (30%, 50%, 70%, 80%, 95% and 3× of 100%) for 10 min each, and further dehydrated in propylene oxide twice for 15 min each. These dehydrated cyst specimens were embedded in Spurr's resin and then polymerized at 70°C for 8 h in a dry oven to make resin blocks containing the cyst specimens (Kim et al, 2017). Resin blocks were trimmed to expose cyst specimens and sectioned 1.0 μm thick with a diamond knife (MF1758, Diatome, Nidau, Switzerland) on an MT-X ultramicrotome (RMC, Tucson, AZ, USA).…”

“…For examining cyst wall thickness and structures by SEM, cyst specimens (cut or intact) were dehydrated using the same ethanol series as LM mentioned above, and dried in a critical point dryer (EM CPD 300, Leica, Wetzlar, Germany) after transition of the specimens through 100% isoamyl acetate two times for 10 min each at room temperature (Kim et al, 2017). These dried cyst specimens were mounted on metal stubs and coated with gold using a sputter coater (EM ACE 200, Leica, Vienna, Austria).…”

Studies on the Soil Nematode Diversity in Relation to the Soil Parameters from Sugarcane Fields of Aurangabad District Maharashtra State, India

“…For example, Meloidogyne spp. is abundantly found in sandy soils than the clay soils [2,3]. Soil nematodes are very small near about 0.3-5.0mm long as adults.…”