Greenhouse and field experiments were conducted to investigate degradation rates and efficacy of EPTC (S-ethyl dipropyl carbamothioate), butylate [S-ethyl bis(2-methylpropyl)carbamothioate], vernolate (S-propyl dipropylcarbamothioate), and cycloate (S-ethyl cyclohexylethylcarbamothioate) in soils with and without prior history of thiocarbamate use. Herbicide persistence was measured by an oat (Avena sativa L.) bioassay, and giant foxtail (Setaria faberi Herrm. # SETFA) control was visually estimated in field studies. Both greenhouse and field studies indicated that enhanced thiocarbamate degradation occurred when the same herbicide (EPTC, butylate, or vernolate) was applied over successive years. Addition of dietholate (O,O-diethyl O-phenyl phosphorothioate) or fonofos (O-ethyl-S-phenylethylphosphonodithioate) increased thiocarbamate persistence and giant foxtail control in soils with prior thiocarbamate exposure. Use of dietholate or fonofos two or three consecutive years with EPTC or butylate again resulted in enhanced degradation. EPTC persistence and giant foxtail control were not affected by prior treatments or tank mixes with carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate). Rotation away from successive applications of the same thiocarbamate herbicide (EPTC, butylate, or vernolate) improved herbicide efficacy.

Field studies were conducted in 1992 and 1993 to evaluate AC 263,222 applied postemergence (POST) alone and as a mixture with atrazine or bentazon for weed control in imidazolinone-resistant corn. Nicosulfuron alone and nicosulfuron plus atrazine were also evaluated. Herbicide treatments were applied following surface-banded applications of two insecticides, carbofuran or terbufos at planting. Crop sensitivity to POST herbicides, corn yield, and weed control was not affected by insecticide treatments. AC 263,222 at 36 and 72 g ai/ha controlled rhizomatous johnsongrass 88 and 99%, respectively, which was equivalent to nicosulfuron applied alone or with atrazine. AC 263,222 at 72 g/ha controlled large crabgrass 99% and redroot pigweed 100%, and this level of control exceeded that obtained with nicosulfuron alone. AC 263,222 at 72 g/ha controlled sicklepod and morningglory species 99 and 98%, respectively. Nicosulfuron alone or with atrazine controlled these two species less than AC 263,222 at 72 g/ha. Addition of bentazon or atrazine to AC 263,222 did not improve control of any species compared with the higher rate of AC 263,222 at 72 g/ha applied alone. Corn yield increased over the untreated control when POST herbicide(s) were applied, but there were no differences in yield among herbicide treatments.

Field experiments were conducted at two locations in 1989 and 1990 to investigate possible interactions between POST applications of primisulfuron and selected soil-applied carbamate and organophosphate corn insecticides. Insecticides were applied in-furrow at planting, at recommended use rates. Primisulfuron was applied POST to corn in the three- or five-leaf stage at 0, 20, 40, or 80 g ai ha-1. Combinations of primisulfuron with disulfoton, fonofos, isozophos, or terbufos resulted in foliar and root injury, plant height reductions, and yield losses. No foliar or root injury, plant height reductions, or yield losses were observed from combinations of primisulfuron and carbaryl, carbofuran, chlorpyrifos, or diazinon. Differences among and within the experiments are attributed to edaphic and environmental conditions at the time of primisulfuron application.

The relationship between the use of pesticides and grey partridge poisoning, mainly due to irregular use of rodent baits, is reviewed in the current paper. The aim of this review is to emphasise the existing problem of partridge extinction and how it would impact the agriculture ecology. A drastic decline in the population of Grey Partridge Perdix perdix has been observed in the Republic of Serbia as well as in many other countries, due to intensive agriculture, predominantly caused by the abuse of pesticides. Pathological and toxicological findings indicate poisoning, and this can be confirmed with gas chromatography-mass spectrometry (GC-MS). Actions such as monitoring and reporting incidents in the future should provide questions of how to improve and implement the established regulations.

Farmlands can be good habitat for owls and owls can benefit farmers, but pesticide use can negatively affect owls and within many regions of Africa owls are loathed owing to beliefs that they bring misfortune or death. Since 1997, a small-scale owl tourism initiative that educates farmers about owls and benefits them financially has been operating in central Kenya. Pesticide use, farmers' beliefs and knowledge about owls, and the impacts that tourism can have on farmers' attitudes and behaviour towards owls in rural Kenya were surveyed. Agricultural pests were the most serious problem facing farmers, though only 28 % of farmers said they controlled vertebrate pests using pesticides. The insecticide carbofuran was often misused to kill vertebrate pests. Common control measures were either to ‘do nothing’ or to chase pests from farms. Farmers knew of Mackinder's eagle owls living adjacent to their farms, but 68 % said they didn't adhere to the culturally negative beliefs about owls. Knowledge of owl diet amongst farmers was high (75 %). Farmers who benefited from owl tourism were more likely to know more about owl diet and habits. Where farmers gained financial benefits from tourism or knew more about owls, they were more likely to categorize owls as ‘good’, but farmers who knew about owl diet were more likely to use pesticides or kill owl prey on their farms. Though knowledge of owls did not have a positive effect on farmers' behaviour toward owls, this was probably the result of a lack of ecological literacy rather than any deliberate antagonism toward owls. Financial rewards are very important to poor farmers, but may not result in actions that enhance species conservation unless farmers have a basic understanding of ecological processes.

This paper reviews the immunomodulatory effects (immunosuppression or immunoactivation) of various anthelmintics including levamisole, fenvalerate, dieldrin, carbofuran, aminocarb, thiabendazole, fenbendazole, oxfendazole and ivermectin. The induced modulation of immune function may occur via direct and/or indirect mechanisms. The immunomodulatory effects of these anti-parasitics have been studied in a variety of bacterial (e.g. brucellosis, salmonellosis, paratuberculosis, mastitis), viral (e.g. infectious bovine rhinotracheitis, Herpes, foot and mouth disease), parasitic (e.g. onchocerciasis, coccidiosis, ascariasis, schistosomiasis) and neoplastic diseases. Some antiparasitics have also been used to boost immunity in a number of human diseases including leprosy, Hodgkin's disease, rheumatoid arthritis, and in adjuvanted therapy of colorectal cancer. The ability to stimulate the immune response of animals offers a new means of disease intervention. Future research on immunomodulatory effects of anti-parasitics, for humans and domestic farm animals, will provide additional methods of treating immunosuppressed subjects. The immunopotentiating or immunosuppressing activity of anti-parasitics will dictate whether co-administration of vaccines and anthelmintics or administration of vaccines during the window of immunoactivation is justified or not.

The effect of infestation of lepidopteran borers on yield of maize was assessed at three locations in the forest and forest/savanna transition zones of Cameroon, during the first and second season of 1992. Maize was treated once or twice with the systemic carbofuran at different developmental stages. The species encountered were the stem-boring noctuids Busseola fusca and Sesamia calamistis, which oviposit on and attack pre-tasseling stages of maize; the stem-boring pyralid Eldana saccharina, which attacks plants at and after tasseling; and two ear borers, namely the pyralid Mussidia nigrivenella and the tortricid Cryptophlebia leucotreta. Generally, carbofuran reduced infestations by B. fusca and S. calamistis but had little or no effect on species attacking the plant's later stages. Thus early treatments with granules into the whorl were more efficient than late treatments as a side dressing, and a second late treatment had little effect. During the first season, late-attacking species were predominant and grain yield losses of 17–44 % were found in one location only. During the second season, species attacking young plants (mainly B. fusca) became predominant in all three locations and yield losses of 30 to 41 % were found in two of the three locations. The percentage of ears with damage was especially high during the second season. As green maize is an important source of cash income in the area and damaged ears cannot be sold, the economic loss was likely considerable.

Studies on critical time of insecticidal protection in relation to damage by aphid, Aphis gossipii Glover and leafhopper, Amrasca biguttula biguttula Ishida on plant growth and yield of okra revealed that 21–42 days after germination, was the most critical time prior to fruiting. Application of carbofuran at the time of sowing was redundant. Effective plant protection 21–42 days after germination resulted in lowest leafhopper and aphid infestation and subsequently the highest benefit to cost ratio.

The biology of the sorghum shootfly, Atherigona soccata Rondani, was studied at the Corn and Sorghum Research Centre, Thailand. The preoviposition period is 3–5 days long. The females deposited a mean of 238 eggs with an average incubation period of 3 days. The larval development required an average of 7.8 days, and the pupal stage was 7.1 days long. The adults were reared with ordinary sugar, yeast and water. The females lived an average of 30 days and the males 20 days.

Carbofuran granular formulation is still the leading product for the control of the shootfly at the Research Centre. The application rate in the seed furrow is 0.45–0.60 kg a.i./ha with a row spacing of 75 cm. Furadan® 30ST, an emulsifiable formation of carbofuran, can also be used as a seed dressing at a rate of 20 cm3/kg of seeds. Counter®, another soil systematic insecticide, has been found effective in controlling the sorghum shootfly.

A modification of the ICRISAT trap for the sorghum shootfly is described. The trap may be effective in reducing the fly population.

An integrated approach to the management of the sorghum shootfly (to keep its population below economic injury level) has been a major thrust of sorghum research workers during the last one and a half decades. The necessary foundation has been laid by detailed studies on the biology of the pest and a fairly thorough understanding of the effect of different ecological factors on the shootfly population. Based on seasonal incidence studies, sowing immediately after the onset of monsoon has proved to be effective for avoiding shootfly damage.

A large number of high yielding and shootfly-resistant derivatives have been developed by crossing agronomically desirable exotic lines with identified resistant sources. The new hybrids and varieties released recently possess low to moderate levels of resistance.

Parasites and predators affecting different stages of the shootfly have been identified but utilization of these natural enemies for the biological control of the pest is yet to be undertaken.

Carbofuran seed treatment has proved to be highly effective for protecting sorghum from shootfly damage. Some other insecticides have also been found to be promising.

Based on the control methods available at present, an integrated package has been recommended for implementation in traditional sorghum growing areas of the country.

The sorghum shootfly, Atherigona seccata Rondani, is the main species of Atherigona attacking cultivated and wild species of Sorghum in Africa and Asia. The past 55 years' research on the pest has produced means for its management. The bionomics of A. soccata are well known and are being applied for its cultural control by adjusting planting dates. Natural enemies of the shootfly are few and their biology little known. The systemic insecticide carbofuran as a seed and seed furrow treatment provides effective fly control where the cost-benefit is favorable. Sources of host plant resistance to shootfly have been recognized for about 35 years. Incorporation of this resistance in high yielding varieties through plant breeding should be more rapid now that the mechanisms of resistance and their inheritance, through additive gene action, are better understood. These resistance factors include non-preference for oviposition, antibiosis and recovery through tillering.

The introduction of high yielding sorghum hybrids in the mid-1960s indicated that the new cultivars were highly susceptible to insect pest attack. Use of chemicals for the control of the snootily, Atherigona soccata (Rondani), became necessary to realise a full yield potential.

This paper briefly reviews the earlier work on conventional foliar sprayings and dustings of the available insecticides which generally failed to give an effective control of the shootfly.

Work carried out in the early 1960s showed that the application of phorate, disulfoton, aldicarb and carbofuran granules in the soil at the time of sowing was very effective in controlling the pest. Recently two more insecticides, viz. isofenphos and fensulfothion have been found to be equally effective. However, the cost of applying these insecticides is rather high.

Seed treatment with carbofuran at 5 parts a.i. per 100 parts of seed proved to be highly effective and economical. It is now being widely used by farmers in the major sorghum growing area of the country. It has been found that dosage of carbofuran can be further reduced by using a 6:4 mixture of treated and untreated seed.

Trials have been conducted to determine the residues of effective insecticides in the soil and in plants at different intervals. Investigations have also been carried out to establish the correlation between the residues of different insecticides in plants and their efficacy in controlling the shootfly. A future strategy for the chemical control of the shootfly is outlined.