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In the past, most of the open lands of arid areas were used as rangelands because of the pivotal role of grazing in the life of the indigenous populace. Currently, because of the competition between grazing and other types of land management (crops’ breeding, urbanisation, etc.) and the seemingly destructive effect of the grazing on the ecosystem, only a reduced part of the open lands is used for grazing. Even in the lands that are allocated to pasture, many restricting’ legislations have been enforced by the authorities. Consequently, these policies have resulted in the dramatic reduction in the profits of the herd owners and a drastic decrease in the rate of grazing, which resulted by ecological catastrophes such as wide spread of fires and invasion of exotic species. In order to achieve a sustainable and profitable utilization of these open lands, we used an alternative approach, which based on the physical interactions of the animals with the ecosystem. This scheme takes into consideration the physical interactions of the bred animals with the ecosystem there, the statutory state of the lands, and the social patterns of the indigenous farmers, as parameters for a holistic solution for arid lands.

Trampling, vegetation harvesting, and excrement spreading are the means by which ruminants interact with the ecosystem. Several mechanisms were described for the influence of vegetation harvesting and excrement spreading on the ecosystem, whereas the influence of trampling is poorly understood. The goal of the present study was to determine the influence of trampling by small ruminants on the ecosystem. The study took place in 2018 and 2019 in the north-western Negev. Each plot included a fenced control-enclosure subplot that is protected from grazing; its remaining area was grazed by a controlled sheep flock. The findings indicate that the crumbling of the surface soil and its mixing with the vegetation, caused by trampling, increased litter production six- to nine-fold compared with the control. The plant litter was better composted by two- to seven times, and its lignin and protein contents were increased by 10%. We suggest that the findings indicate the positive influence of trampling by small ruminants in enhancing soil fertility, even under arid climatic conditions and loamy soil. Nevertheless, a further experimental study is needed, in additional experimental sites, in order to work out practical guidelines for the farmers.

The aim of this study was to investigate the function of tree belts in reducing the aeolian transport of dust particles carrying pesticides. The study examined the importance of the buffer zones created by commonly planted trees (Eucalyptus camaldulensis, Pinus halepensis (pine) and Ceratonia siliqua (carob)). The methods include analyzing the quantity and the chemical composition of pesticides carried by aeolian dust particles from the intensively cultivated fields and orchards, where pesticides were applied, towards the tree belts nearby. Eighteen different chemicals used as insecticides, fungicides and herbicides, were found both in the agricultural fields and in the adjacent tree belts, suggesting an important function of the trees. This ecological service has rarely been taken into consideration by management policies of tree plantings in farmland areas. To integrate this service into agriculture, especially in the case of agricultural fields and orchards, which are adjacent to populated areas, planting tree belts should be positively considered as a means for reducing aeolian dust and air pollution, mainly in order to reduce leakage of pesticides, which are a cause for significant health concerns.

BACKGROUND Restrictions on soil fumigants are prompting the development of new compounds for controlling nematodes, other soilborne pathogens and weeds. We evaluated the nematicidal activity of five bromine compounds against Meloidogyne javanica in vitro, and tested the two most effective ones against Pratylenchus penetrans and Xiphinema index in vitro and in soil. RESULTS Only allyl bromide and dibromo(nitro)methane showed nematicidal activity against M. javanica juveniles in vitro at

Ochradenus baccatus is a widely distributed shrub in desert regions of the Middle East and North Africa. This plant’s nematicidal activity against the root-knot nematode Meloidogyne javanica was evaluated because it has been found to contain exceptionally high levels of glucosinolates. In in vitro assays with aqueous extracts of the plant, 100% of second-stage juveniles were immobilized after exposure to 4% root-core extract for 48 h; 8% root-core extract suppressed their hatching by 87%, whereas stem, flower and root bark showed lower activity. Incorporation of root core or bark into the soil, as fresh or dry powder at 1 and 05% (w/w), respectively, reduced the number of nematodes recovered from the soil by 95–100%, whereas the flower and stem were much less effective. Results from further pot experiments indicated that only the root bark consistently contains nematicidal compounds which are effective in soil, whereas the nematicidal activity of the root core in soil was inconsistent. The presence of non-volatile lipophilic and lipophobic nematicidal compounds in the root bark was suggested by extraction with different polar solvents, but these compounds do not seem to be isothiocyanates – glucosinolate-hydrolysed compounds with nematicidal activity. Very poor host status of Ochradenus baccatus to M. javanica, M. incognita and M. hapla, but with root-penetration rates of juveniles similar to those in tomato roots, suggest that this plant may be used as a cover plant or trap plant to reduce nematode populations in the soil.

BACKGROUND Fluensulfone, a fluoroalkenyl group nematicide, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp. The authors evaluated some soil environmental factors that might affect its nematicidal activity. RESULTS Meloidogyne javanica juveniles exposed to fluensulfone lost their infectivity, even though they were rinsed in water when they were still active. Exposure of juveniles to fluensulfone at >1 mg L−1 for 48 h was very effective in reducing root galls. Peat as organic matter added to soil reduced nematicidal efficacy against M. javanica in pot experiments. Peat added to a soil column inhibited the downward movement of fluensulfone. The movement of fluensulfone was faster in sandy vs loess soil. Repeated soil application of fluensulfone did not reduce the nematicidal activity of fenamiphos or cadusafos, and repeated applications of these nematicides did not lower the nematicidal activity of a subsequent application of fluensulfone. CONCLUSION Fluensulfone nematicidal activity and movement were affected by organic matter and clay content, probably via adsorption. Enhanced biodegradation or cross-biodegradation of fluensulfone by other compounds was not observed. Soil environment should be considered to obtain effective nematode control efficacy with a given compound. © 2013 Society of Chemical Industry

BACKGROUND: Fluensulfone, a new nematicide of the fluoroalkenyl group, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp., by soil application. The systemic activity of this compound against M. incognita on peppers via soil drenching and foliar spray was evaluated. RESULTS: Root application of fluensulfone via soil drenching showed slight and no nematode control activity when applied 4 and 10 days, respectively, after inoculation. A single foliar spray of peppers with a fluensulfone solution at 3.0 g L−1 prior to inoculation reduced the galling index by 80% and the number of nematode eggs by 73–82% of controls. The reduction in these parameters by fluensulfone was much higher than that obtained with oxamyl or fenamiphos at the same concentration. This activity was also observed when the plants were sprayed 21 days before inoculation. A series of experiments suggested that foliar spray with fluensulfone prior to inoculation reduces nematode invasion. However, foliar spray after inoculation did not inhibit nematode development inside roots. CONCLUSION: Fluensulfone showed relatively high nematode control activity when sprayed on the foliage before inoculation. Fluensulfone may be used as a foliar application, in addition to soil application, for root-knot nematode control. Copyright © 2011 Society of Chemical Industry

BACKGROUND: The small number of available nematicides and restrictions on the use of non-fumigant nematicides owing to high toxicity to human and non-target organisms hinder effective nematode control. The nematicidal efficacy of MCW-2, a new nematicide of the fluoroalkenyl group, was evaluated against the root-knot nematode Meloidogyne javanica (Treub.) Chitwood. RESULTS: MCW-2 showed irreversible nematicidal activity against second-stage juveniles of M. javanica in vitro, following exposure for 48 h at concentrations as low as 0.5 mg L−1, in contrast to fenamiphos or cadusafos. When exposed to MCW-2 for shorter periods, motile juveniles became immobile with time after rinsing in water. MCW-2 at 8 mg L−1 inhibited nematode hatching, which, however, recovered after rinsing in water. In pot and plot experiments, 0.5 mg MCW-2 L−1 soil and 2 kg MCW-2 ha−1, respectively, controlled M. javanica similarly to or better than fenamiphos or cadusafos at the same concentrations or at their recommended doses. In the soil, the nematicidal activity of MCW-2 was less persistent than that of fenamiphos. CONCLUSION: MCW-2 has potential to be used as a new non-fumigant nematicide that probably has a novel mode of action. Copyright © 2009 Society of Chemical Industry

Nematicidal activities of ammonia-releasing organic and inorganic fertilisers, applied with alkaline amendments, were tested against Meloidogyne javanica and M. incognita under field conditions. In microplots infested with M. javanica, ammonium sulphate applied with alkaline-stabilised biosolid (ASB) significantly reduced the root-galling index of tomato plants compared with that of plants grown in soils treated with ammonium sulphate or ASB alone. Although ammonia concentrations in the soil treated with broiler litter plus cement kiln dust were high (ca 60-200 mg kg−1), this treatment was less effective. Ammonia volatilisation resulted in rather low concentrations of ammonium in the soils treated with alkaline amendments. The combination of ASB and ammonium sulphate reduced the tomato root-galling index and the number of M. javanica juveniles recovered from the soil in a field experiment. On an organic farm, application of slaked lime in combination with broiler litter significantly reduced the root-galling index of pepper plants infested with M. incognita. Calcification of excess hydroxyls in the ASB or lime lowered the soil pH to values normally found in these soils in the field experiments.

Nematicidal activities of ammonia-releasing organic and inorganic fertilisers, applied with alkaline amendments, were tested against Meloidogyne javanica and M. incognita under field conditions. In microplots infested with M. javanica, ammonium sulphate applied with alkaline-stabilised biosolid (ASB) significantly reduced the root-galling index of tomato plants compared with that of plants grown in soils treated with ammonium sulphate or ASB alone. Although ammonia concentrations in the soil treated with broiler litter plus cement kiln dust were high (ca 60-200 mg kg−1), this treatment was less effective. Ammonia volatilisation resulted in rather low concentrations of ammonium in the soils treated with alkaline amendments. The combination of ASB and ammonium sulphate reduced the tomato root-galling index and the number of M. javanica juveniles recovered from the soil in a field experiment. On an organic farm, application of slaked lime in combination with broiler litter significantly reduced the root-galling index of pepper plants infested with M. incognita. Calcification of excess hydroxyls in the ASB or lime lowered the soil pH to values normally found in these soils in the field experiments.

Restrictions on soil fumigants are prompting the development of new compounds for controlling nematodes, other soilborne pathogens and weeds. We evaluated the nematicidal activity of five bromine compounds against Meloidogyne javanica in vitro, and tested the two most effective ones against Pratylenchus penetrans and Xiphinema index in vitro and in soil.Only allyl bromide and dibromo(nitro)methane showed nematicidal activity against M. javanica juveniles in vitro at320 mg L(-1) . Allyl bromide killed M. javanica and P. penetrans at 20 mg L(-1), and X. index at 10 mg L(-1), whereas 320 mg dibromo(nitro)methane L(-1) was required to kill P. penetrans. Allyl bromide also showed higher nematicidal activity than dibromo(nitro)methane against M. javanica and P. penetrans in soil. Allyl bromide at 40 and 20 mg L(-1) soil eliminated root galls and nematode eggs on tomato roots grown in M. javanica-inoculated loess and sandy soils respectively, showing higher nematicidal activity than 1,3-dichloropropene. No P. penetrans were recovered from soil treated with 80 mg allyl bromide L(-1) soil or 320 mg dibromo(nitro)methane L(-1) soil.Allyl bromide showed high nematicidal activity against all three nematode species, and nematicidal activity of dibromo(nitro)methane was discovered. These compounds could serve as new fumigation nematicides, pending further experiments.

Fluensulfone, a fluoroalkenyl group nematicide, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp. The authors evaluated some soil environmental factors that might affect its nematicidal activity.Meloidogyne javanica juveniles exposed to fluensulfone lost their infectivity, even though they were rinsed in water when they were still active. Exposure of juveniles to fluensulfone at1 mg L(-1) for 48 h was very effective in reducing root galls. Peat as organic matter added to soil reduced nematicidal efficacy against M. javanica in pot experiments. Peat added to a soil column inhibited the downward movement of fluensulfone. The movement of fluensulfone was faster in sandy vs loess soil. Repeated soil application of fluensulfone did not reduce the nematicidal activity of fenamiphos or cadusafos, and repeated applications of these nematicides did not lower the nematicidal activity of a subsequent application of fluensulfone.Fluensulfone nematicidal activity and movement were affected by organic matter and clay content, probably via adsorption. Enhanced biodegradation or cross-biodegradation of fluensulfone by other compounds was not observed. Soil environment should be considered to obtain effective nematode control efficacy with a given compound.

Fluensulfone, a new nematicide of the fluoroalkenyl group, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp., by soil application. The systemic activity of this compound against M. incognita on peppers via soil drenching and foliar spray was evaluated.Root application of fluensulfone via soil drenching showed slight and no nematode control activity when applied 4 and 10 days, respectively, after inoculation. A single foliar spray of peppers with a fluensulfone solution at 3.0 g L(-1) prior to inoculation reduced the galling index by 80% and the number of nematode eggs by 73-82% of controls. The reduction in these parameters by fluensulfone was much higher than that obtained with oxamyl or fenamiphos at the same concentration. This activity was also observed when the plants were sprayed 21 days before inoculation. A series of experiments suggested that foliar spray with fluensulfone prior to inoculation reduces nematode invasion. However, foliar spray after inoculation did not inhibit nematode development inside roots.Fluensulfone showed relatively high nematode control activity when sprayed on the foliage before inoculation. Fluensulfone may be used as a foliar application, in addition to soil application, for root-knot nematode control.

The small number of available nematicides and restrictions on the use of non-fumigant nematicides owing to high toxicity to human and non-target organisms hinder effective nematode control. The nematicidal efficacy of MCW-2, a new nematicide of the fluoroalkenyl group, was evaluated against the root-knot nematode Meloidogyne javanica (Treub.) Chitwood.MCW-2 showed irreversible nematicidal activity against second-stage juveniles of M. javanica in vitro, following exposure for 48 h at concentrations as low as 0.5 mg L(-1), in contrast to fenamiphos or cadusafos. When exposed to MCW-2 for shorter periods, motile juveniles became immobile with time after rinsing in water. MCW-2 at 8 mg L(-1) inhibited nematode hatching, which, however, recovered after rinsing in water. In pot and plot experiments, 0.5 mg MCW-2 L(-1) soil and 2 kg MCW-2 ha(-1), respectively, controlled M. javanica similarly to or better than fenamiphos or cadusafos at the same concentrations or at their recommended doses. In the soil, the nematicidal activity of MCW-2 was less persistent than that of fenamiphos.MCW-2 has potential to be used as a new non-fumigant nematicide that probably has a novel mode of action.