Biocontrol agents including fungi; Trichoderma harzianum and Penicillium sp., and bacteria;- Pseudomonas fluorescens, Bacillus sp. and Streptomyces sp. applied to cotton seeds (Takfa 1) were evaluated for the control of damping-off caused by Rhizoctonia solani. The results indicated that biocontrol agents applied to the seeds both in the sole and combination treatments decreased the infection percentage by 15.0 to 57.5 % Bacillus sp. alone showed the most effective against R. solani, and was also more effective than a fungicide; carboxin (vitavax 75 WP.). The combination treatments were usually more effective than the sole treatments. Culture filtrate of Streptomyces sp. decreased the disease incidence whether using alone or combining with other agents. Populations of fungi and bacteria recovered from the surface of coated seeds were greater than 10 (exp.6) colony forming units per seed.

The extent of pesticide use and the prevalence of pest populations on field crops vary according to the type of pest, crop, region, and survey year. This report estimates the importance of individual pests on selected field crops on a regional and national basis. Surveyed farmers report the most severe and intense pests were weeds in corn and soybean production, weeds and insects in cotton, and diseases and insects in tobacco.

The percentage of Verticillium wilt infestation (foliar symptoms) on cotton plants grown in a highly infested field at Sindos during 1976-79 was 10%-26% in July and 28%-59% in August. The degree (severity) of infestation was less differentiated and not always proportional to the percentage of infested plants which means that the product of these two coefficients is a more reliable disease criterion. The aggravation of infected plants symptoms was also independent of wilt percentage and greater for the mild degrees of infection. The varieties responded differently to the wilt infestation. Early varieties were generally more susceptible to the early and late varieties to the late infestation. Similar reaction was also displayed between early and late sowing. Varietal yield was affected, but not entirely, by disease resistance. The increased plant population in double rows and the sowing on beds restricted infestation, but the yield was increased only by the first factor. Early sowing, in spite of greater infestation and disease losses, yielded more than the late one. Yield loss was proved proportional to the: percentage, degree and duration of infestation. Cotton plants with infestation degrees in July 1, 2, 3, 4 yielded respectively 51.3%, 40.6%, 20.9% and 4.0% of healthy plants while those infected in August yielded respectively 88.7%, 68.6%, 45.9% and 26.6%. The yield loss per area, due to the infestation of July and August was 10% and 12% respectively. Mean boll weight was decreased by 0.39 g. The reduction was proportional to the infestation degree and generally greater due to late infestation. Among the technological characters only Micronaire index was lowered by 0.20 units.

Results of the studies on diseases and parasites of marine shrimp, Penaeus monodon and P. merguiensis which are considered as the most economically important species for the shrimp farming in Thailand were presented. The most serious case that cause great lose after hatching to nursing period due to ecto-commensals protozoa; Zoothamnium and Epistylis. Vibrio bacteria aud fungus, Lagenidium were considered as the pathogenic microorganisms caused second degree of losess. The other protozoa that cause minor damage are Acineta, Lagenophrys and Licmophora. Diseses and parasites occurred during rearing period included cotton or milkly shrimp diseases caused by Microsporidian protozoa (Thelohania sp.), black gill disease caused by fungus Fusarium. Common parasitic founa in the digestive tract were Thynnascaris sp., Spirocamallanus larvae, tapeworm, Prochristianella penaei and parasitic protozoa Cephalolobus sp., Parasitic copepod, Caligus epidemicus found in our studies was the first known record on an invertebrate host. Prevention and control measures were given accordingly.

There are very few reports on the diseases, parasites, commensals and fouling in penaeid prawns. During the regular collection of marine and estuarine prawns in the east coast of India, a number were found to be infested with various organisms. The prawn Penaeus (Fenneropenaeus) indicus, was infested with a microsporidian which causes a condition known as milk or cotton prawn. The infestation was spread throughout the abdominal musculature of the prawn. The marine prawn Parapenaeopsis stylifera had epibiotic growth of athecate hydrozoans, probably of the genus Tubularia, on the dorsal side of the carapace and abdominal segments. This is the first report of athecate hydrozoans infesting the prawn. The prawn Metapenaeopsis stridulans was observed to be parasitized by a bopyrid isopod, Orbione thielemanni and the prawn Sicyonia lancifera, parasitized by another bopyrid isopod, O. kemi. The bopyrid isopod O. kemi infesting the prawn S. lancifera is also recorded for the first time. Both bopyrid isopods were found in the branchial cavity of the prawns. The Pontoniinid prawn Chernocaris placunae is a commensal living in the mantle cavity of the bivalve, Placenta placenta. Barnacles were found attached to the carapace and first abdominal segment of the prawn, Parapenaeopsis uncta, whereas they were found in the telson region also in the prawn P. stylifera. Most of the barnacles were very small with a basal diameter of less than 1.5 mm.

There are very few reports on the diseases, parasites, commensals and fouling in penaeid prawns. During the regular collection of marine and estuarine prawns in the east coast of India, a number were found to be infested with various organisms.The prawn Penaeus (Fenneropenaeus) indicus, was infested with a microsporidian which causes a condition known as milk or cotton prawn. The infestation was spread throughout the abdominal musculature of the prawn. The marine prawn Parapenaeopsis stylifera had epibiotic growth of athecate hydrozoans, probably of the genus Tubularia, on the dorsal side of the carapace and abdominal segments. This is the first report of athecate hydrozoans infesting the prawn. The prawn Metapenaeopsis stridulans was observed to be parasitized by a bopyrid isopod, Orbione thielemanni and the prawn Sicyonia lancifera, parasitized by another bopyrid isopod, O. kemi. The bopyrid isopod O. kemi infesting the prawn S. lancifera is also recorded for the first time. Both bopyrid isopods were found in the branchial cavity of the prawns. The Pontoniinid prawn Chernocaris placunae is a commensal living in the mantle cavity of the bivalve, Placenta placenta. Barnacles were found attached to the carapace and first abdominal segment of the prawn, Parapenaeopsis uncta, whereas they were found in the telson region also in the prawn P. stylifera. Most of the barnacles were very small with a basal diameter of less than 1.5 mm. | Abstract only.