scholarly journals Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar): A Mesocosm Experiment

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Cécile Villenave ◽  
Bodo Rabary ◽  
Emilie Kichenin ◽  
Djibril Djigal ◽  
Eric Blanchart
Keyword(s):  
Community Structure ◽  
Soil Surface ◽  
Nematode Community ◽  
Mesocosm Experiment ◽  
Plant Residues ◽  
Biological Processes ◽  
Organic Residues ◽  
Free Living ◽  
Specific Stimulation ◽  
Stimulation Of

Free-living nematodes present several characteristics that have led to their use as bioindicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm,Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean) were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders) was higher in presence ofP. corethrurusthan in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

scholarly journals (125) Effect of Organic Residues on Shoot and Root Growth of Apple Tree

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1061D-1061
Author(s):  
Davide Neri ◽  
Gianpaolo Mascanzoni ◽  
Paolo Sabbatini ◽  
Franco Zucconi ◽  
James Flore
Keyword(s):  
Shoot Growth ◽  
Apple Tree ◽  
Sandy Loam ◽  
Soil Surface ◽  
Dry Weight ◽  
Plant Residues ◽  
Organic Residues ◽  
Mature Compost ◽  
Loam Soil ◽  
Old Trees

To simulate soil sickness, 1-year-old trees of `Golden Delicious' (grafted on M9 and M106) were grown in rhizotrons (1 × 1-m and 0.5-m depth) with different plant residues content, at Ravenna, Italy. Sandy loam soil was used as a substrate. Fine-grounded wood from apple and peach residues (6 kg per rhizotron) was mixed to the substrate and considered as main treatment. Mature compost (1% and 2.5% in volume) was added or not to the substrate with the organic residues and considered as subtreatment. The application of residues was localized either near the soil surface (0–25 cm) or deeper in the soil profile (25–50 cm). In each rhizotron, four trees on the same rootstock were planted and each soil treatment was replicated twice. After 2 years, the roots were accurately excavated (washing off the soil with water), and growth was measured. The presence of apple residues near the soil surface induced a 5% to 20% reduction of shoot growth. The reduction per plant dry weight was higher when trees were grafted on M106. At root level, the presence of residues increased the root migration in the search for fresh niches, enhancing root crossing and anastomosis. Both these shoot and root conditions are typical of replant diseases symptoms. The localization of apple residues in the lower part of the profile reduced the symptoms and so did the addition of compost. The peach residues did not affect shoot growth when compared to the control, but the shoot-to-root ratio was reduced, indicating a tendency to increase root migration.

DECOMPOSITION OF ORGANIC RESIDUES AS AFFECTED BY VARIOUS DRYLAND SPRING WHEAT-FALLOW ROTATIONS

1980 ◽  
Vol 60 (1) ◽  
pp. 97-106 ◽  
Author(s):  
J. F. DORMAAR ◽  
U. J. PITTMAN
Keyword(s):  
Soil Surface ◽  
Soil Samples ◽  
Plant Residues ◽  
Caloric Content ◽  
Organic Residues ◽  
Total N ◽  
Percentage Points ◽  
Native Grassland ◽  
Below Ground ◽  
Annual Application

Three non-replicated, non-fertilized, dryland grain rotations — continuous wheat, wheat-fallow, and wheat-wheat-fallow — were established in 1912 on a Dark Brown Chernozemic soil. In 1967, the rotations were altered to include an annual application of 45 kg N/ha to a portion of each field. Above- and below-ground organic residue and soil were sampled in September 1975, April and August 1976, and April 1977 from both the fertilized and non-fertilized treatments of each rotation to measure the effects of the rotations on a number of chemical characteristics. The soil samples were analyzed for pH and contents of C, N, ethanol/benzene- and resin-extractable C, polysaccharides, and waterstable aggregates. The organic residues were analyzed for contents of C, N, ethanol/benzene-extractable C, lignin, and methoxyl groups, and for caloric content. The soils of the continuous wheat rotation contained the most C, total N, and polysaccharides, whereas the soils of the wheat-fallow rotation were about 12 percentage points higher in resin-extractable C than those of the continuous wheat or wheat-wheat-fallow rotations. The cultivated soils contained 47% less C, 46% less N, 53% less polysaccharides, 100% more solvent-extractable C, 49% more resin extractable C, and a slightly higher pH than the soils from the proximate native grassland. Individual rotations had little effect on the chemical composition of organic residues on the soil surface but did affect the decomposition and nature of subsurface plant residues.

Responses of nematode community structure to pesticide treatments in an arid ecosystem of the Negev Desert

Nematology ◽  
2005 ◽  
Vol 7 (2) ◽  
pp. 179-191 ◽  
Author(s):  
◽  
Yosef Steinberger
Keyword(s):  
Community Structure ◽  
Trophic Group ◽  
Shannon Index ◽  
Nematode Community ◽  
Untreated Plot ◽  
Free Living ◽  
Spatial And Temporal Distributions ◽  
Treated Sample ◽  
Significant Difference ◽  
Temporal Basis

AbstractThe aim of this study was to determine the effect of pesticides on free-living soil nematodes in a desert system. Spatial and temporal distributions as well as changes in nematode community structure were investigated. Soil samples were collected monthly between November 2000 and November 2001 from four plots: one treated with Nemacur, one with Edigan, one with water and one untreated plot as control. The nematode population as well as spatial distribution was found to be affected by treatments on a temporal basis. The different treatments applied led to a significant difference in the abundance of nematode trophic groups, where the fungivores and bacterivores were found to decrease in the pesticide-treated samples. A total of 31 genera were found in the samples, with 21 in the Nemacur-treated sample and 16 in the Edigan-treated sample. Ecological indices such as trophic diversity, maturity index and Shannon index elucidated the effect of pesticides on density, diversity and trophic group composition.

Modelling the mineralisation of plant residues on the soil surface

Agronomie ◽  
2002 ◽  
Vol 22 (7-8) ◽  
pp. 711-722 ◽  
Author(s):  
Axel Berkenkamp ◽  
Eckart Priesack ◽  
Jean Charles Munch
Keyword(s):  
Soil Surface ◽  
Plant Residues

REHABILITATION OF THE SOIL STRUCTURE WITH THE DIRECT SOWING IN THE STAVROPOL REGION DRY ZONE

1970 ◽  
pp. 27-31
Author(s):  
V. P. Belobrov ◽  
S. А. Yudin ◽  
V. А. Kholodov ◽  
N. V. Yaroslavtseva ◽  
N. R. Ermolaev ◽  
...  
Keyword(s):  
Cover Crops ◽  
Soil Surface ◽  
Plant Residues ◽  
Agricultural Technologies ◽  
Row Crops ◽  
Dry Zone ◽  
Erosion Effect ◽  
Stavropol Region ◽  
Dry Conditions ◽  
Direct Sowing

The influence of different systems of soil cultivation is considered - traditional (recommended) technology and direct sowing, which is increasingly used under dry conditions of the region. The rehabilitation of the degraded southern chernozems and dark chestnut soils structure during 13 and 7 years of direct sowing, respectively, has not been established. It takes much longer to rehabilitation the aggregate state of soils, which is currently in a critical condition of the content of aggregates> 10 mm in size and the sum of agronomically valuable aggregates. The soils under 60-year treeline, as a control, showed a satisfactory range of aggregates, which indicates a high degree of soil degradation in the past and a long period of their recovery time. The effectiveness of direct sowing usage in the cultivation of a wider range of grain and row crops (winter wheat, sunflower, peas, chickpeas, rapeseed, buckwheat, corn) is due to the peculiarities of agricultural technologies. Abandoning of naked fallows and soil treatments with the simultaneous use of plant residues and cover crops on the soil surface between the harvest and sowing of winter crops provides an anti-erosion effect and, as a consequence, a decrease in physical evaporation, an increase in moisture and biota reserves, an increase in microbiological processes, which are noted in the form trends in improving the agrochemical and agrophysical properties of soils.

Sign in / Sign up

Export Citation Format

Share Document