Nematodes, cultivation

There are known to be about 30,000 disease-causing agents (fungi, viruses, nematodes, bacteria) in 3,000 types of cultivated plants. More than 10,000 species of arthropods (insects, ticks, arachnids) affect agricultural plants and animals. Along with agriculture, pesticides are also widely used in forestry and fisheries, in energy and railroads (to clear plants), in construction (to protect wood structures), etc. 

Tarakanov VI. Methods of continous axenic cultivation of the insect nematode. Neoaplectana glaseri, Turdy Vsesoyuznogo Instituta Gel mintologii. 1980 25 106-110. 

Wilson MJ, Glen DM, George SK, Butler RC. Mass cultivation and storage of the rhabditid nematode Phasmarhabditis hermaphrodita, a biocontrol agent for slugs. Biocont Sci Tech. 1993b 3 513-521. 

Cultivation of cestodes presents a number of problems, many of which are shared with other parasitic helminths, such as trematodes and nematodes (796,800,810). Some problems, however, are unique to cestodes, particularly those related to the tapeworm s lack of an alimentary canal. Since cestodes normally inhabit the intestine of vertebrates, a major stumbling block to culture attempts in the past has been the initial establishment of sterility. Availability of antibiotics such as gentamycin, penicillin and streptomycin has largely eliminated this difficulty, and there now seems no reason why any species from any host habitat cannot be obtained in a sterile condition. 

Results from field experiments suggest that Jerusalem artichoke tubers can be left in nematode-infested soils, without yield being adversely affected. The tubers appear to be resistant to the nematodes that inflict damage on other root vegetables. Cultivation of nematode-neutral Jerusalem artichoke caused a 45% reduction in the potato-eating nematode population in infested fields in one study (Goffart, 1955). Therefore, Jerusalem artichoke is useful as a rotational substitute for sugar beet or potato in nematode-infested fields (Conti, 1953 Kosaric et al., 1984). 

Cultivation of perennial plants does not inhibit nematodes but instead increases them at a depth of 60 cm. 

Control Usually controlled by natural enemies (blister beetle larvae, ground beetles, predatory flies, birds, parasitic nematodes, fungal dieases) cultivate fields in fall to kill overwintering eggs aerial sprays of commercial protozoan disease Nosema locmtae) may be effective over large areas but is not useful on a home-garden scale. 

Control Cultivate thoroughly every week for 4-6 weeks in fall to expose and destroy larvae delay planting tubers and corms until soil is very warm, keeping soil bare until planting allow chickens to run on infested ground to eat larvae bury raw potato pieces 4"-6" deep to attract larvae, check every 1-2 days and destroy wireworms apply parasitic nematodes to soil. 

Hobson, A. D. (1948) The physiology and cultivation in artificial media of nematodes parasitic in the alimentary tract of animals. Parasitology 38 183-227. 

There are two basic problems with using soils for casing—the increased contamination risk from fungi and nematodes, and the loss of structure after repeated waterings. Cultivators can reduce the risk of contamination by pasteurization, a process whereby the moistened casing soil is thoroughly and evenly steamed for twohours aT 160° F. An alternative method is to bake the moist soil in an oven for Two hours aT 1 60 ° F. ... 

One of the best ways to emphasize the importance of the soil animals is to show their numbers as in Table 4.1, taken from Kevan (1965) - see also Fig.4.1. As Kevan states, the upper limits indicated in Table 4.1 are not maximal. In woodland soils, enchytraeids may number up to 270,000 or more per square meter, mites up to 400,000 and Collembola up to 200,000. In cultivated heathland, 800,000 arthropods per square meter have been observed. Kevan states that, exclusive of nematodes and Protozoa, the estimated number of animals may total over 1.5 million per square meter. Fluctuations of numbers of different kinds of animals with environmental conditions and with seasons are very great. More important than numbers, however, are figures for biomass and respiration (see Kevan, 1965 Burges and Raw, 1967). 

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