Local isolates of Bacillus thuringiensis were isolated from infected rice stemborers, soils, rice bran and rice mill dust. Of 83 isolates serotyped by B. thuringiensis H-antisera, 13 serotypes were identified. Those serotypes were assigned to B. thuringiensis of subspecies canadensis, galleriae, kenyae, kurstaki, neoleonensis, aizawai, alesti, entomocidus, tochigiensis and tolworthi. Three serotypes, 3a:3c:3d, 5a:5b/21 and 17/27, were unnamed and portend to be new subspecies. Morphological studies of delta-endotoxin or crystal protein of each subspecies showed significant differences in size and shape. Bipyramidal crystals, spherical and cuboidal crystals and the combinations of these structures were observed. Toxicity of sporulated cultures and isolated crystal proteins of B. thuringiensis strains to five species of economically important insects were determined using diet incorporation bioassays. Extracted crystal proteins from certain B. thuringiensis subspecies were highly toxic to some insect species. These have the potential of providing alternative strategies for utilizing B. thuringiensis for controlling insects.

Longevity and fecundity of the bird cherry‐oat aphid, Rhopalosiphum padi (L.), and the English grain aphid, Sitobion avenae (F.), reared at various densities on caged wheat plants were observed under laboratory conditions. On heading plants, R. padi responded to intraspecific competition by having a significantly shorter life and lower fecundity. When infested with 4 R. padi + 4 S. avenae on the same plant, S. avenae had either no effect or a positive effect on longevity and fecundity of R. padi. The presence of R. padi on wheat sedlings, however, appeared to increase longevity and fecundity of S. avenae. Both species had reduced longevity and fecundity when 16 R. padi + 16 S. avenae were placed on the same plant. The bird cherry‐oat aphid preferred lower parts of the heading plant, while the English grain aphid preferred the plant head. The presence of the two species did not affect the spatial distribution of each aphid species on the plant. Only when crowded by its own species, S. avenae spread downward to avoid intraspecific competition on the wheat head. Zusammenfassung Zur Wechselwirkung zwischen Rhopalosiphum padi (L.) und Sitobion avenae (F.) (Horn., Aphididae) hei gemeinsamem Befall an Weizen Lebensdauer und Fekundität von Rhopalosiphum padi und Sitobion avenae an Weizen wurden im Labor unter unterschiedlichen Befallsdichten untersucht. Im oberen Bereich der Pflanzen reagierte R. padi auf intraspezifische Konkurrenz mit einer signifikant kürzeren Lebensdauer und geringerer Fekundität. Bei einer Dichte von 4 R. padi und 4 S. avenae pro Pflanze, hatte S. avenae keinen oder einen positiven Effekt auf Lebensdauer und Fekundität von R. padi. Das Auftreten von R. padi an Weizensämlingen schien jedoch Lebensdauer und Fekundität von S. avenae zu fördern. Beide Arten hatten eine kürzere Lebensdauer und geringere Fekundität, wenn jeweils 16 Individuen beider Arten pro Pflanze vorhanden waren. R. padi besiedelte bevorzugt die unteren Pflanzenteile, S. avenae die oberen. Durch das gleichzeitige Auftreten beider Arten wurde das Verteilungsmuster nicht beeinflußt. Nur bei gehäuftem Auftreten von Artgenossen befiel S. avenae auch die unteren Pflanzenteile, um eine intraspezifische Konkurrenz zu vermeiden.

This paper will present the interactive research of expert team on Jatropha curcas plantation management to obtain high productivity in terms of dry seed weight per cultivation area. Set of experiments were designed and performed on randomize central block design and triplicate data were collected. The spacing was the important factor along with the cutting management program for long time cultivation. Therefore, the 3 different spacing (2x2, 2x3 and 3x3) were tested. The results show that 2x3 and 3x3 m spacing gave high yield of 129.2 and 127.1 kg/rai for the first cultivation year. In addition, types of insect and pest were surveyed in the Jatropha plantations and the ranking of the most found insect and pest was proposed. Mealy bug, Aphids and coccus were the most found insects in the Jatropha plantation. In the mean time, leaf spot, fungus infection, was the most sever in many areas in Thailand. Then the harmless chemical and biological treatments were tested to control those insects. The harmless chemical such as sodium lauryl sulphate and consumable products (tooth paste, shampoo etc) were used. In case of biological control, the natural predator, green lace wing, of the first top three insects was introduced and tested in the field. On the other hand, the number of insect pollinator was recorded at the Jatropha plantation responding to the Sun direction and time of the day. Interestingly, pollen germination also depends on the Sun direction. On the other hand, Box-Behnken design was used to optimize the transesterification of Jatropha oil to obtain the high fatty acid methyl ester (FAME) percentage. The results show that at the mole ratio of methanol and oil of 9:1, catalyze of 1.5%, reaction time of 72 min and temperature of 60 o C was the optimum condition and 99.0% of FAME was obtained. For the seed cake utilization, different rates of the seed cake (1,600, 800, 400 kg/rai) were applied to the cultivation of Chinese kale, tomato and potato. It was understandable that the mix of chemical fertilizer and Jatropha seed cake (1,600 kg/rai) gave the highest plant performance and no phorbol ester residue left in the cultivation soil and harvested vegetable.