Ketahanan Dan Pengaruh Fitotoksik Campuran Ekstrak Piper Retrofractum Dan Annona Squamosa Pada Pengujian Semi Lapangan

Persistence and Phytotoxic Effect of Extract Mixtures of Piper retrofractum (Piperaceae) and Annona squamosa (Annonaceae) in Semi Field Test. Novel strategy in vegetable pest control program is necessary to be conducted to reduce high rate of synthetic insecticide use. Botanical insecticides offer one of alternatives. Prior to be applied in the field, it has to be evaluated the extract persistence and phytotoxic effect to crops. So, the objective of this research was to study the persistence and phytotoxic effect of extract mixtures of Piper retrofractum (Piperaceae) and Annona squamosa (Annonaceae) in semi field test. Extract mixtures were sprayed on broccoli plants, then at 0,1,2,3,5,7, and 10 days after exposure under sunlight, leaves of broccoli were served to Crocidolomia pavonana (Lepidoptera: Pyralidae) to evaluate the insecticidal activity. The mortality activity of extract mixtures at 0.1% were still high until 10 days exposure. Moreover, no phytotoxic effect was occurred on broccoli plants treated with extract mixtures as high as at 0.1% of extract mixture concentration

Aktivitas Minyak dan Serbuk Enam Spesies Tumbuhan terhadap Peneluran dan Mortalitas Callosobruchus sp. (Coleoptera: Bruchidae)

Storage pests remain one of the main problems in storage. The pest attacks occur not only in the field, but also in storage. Control should be done to maintain the quality of storedproducts. The environmentally friendly measures should be implemented to avoid negative impacts to the environment and human being. The objective of this research was to study the mortality and oviposition deterrence caused by powder and oil of six plant species against Callosobruchus sp. (Coleoptera: Bruchidae). Flowers of Eugenia aromatica, roots of Vetiveria zizanioides, leaves of Pogostemon cablin, seeds of Ricinus communis, seeds of Foeniculum vulgare, and stems of Cymbopogon citratus were air-dried and milled to yield powder. Oil of six plant species were purchased from local market. Oviposition deterrent bioassay was conducted by no-choice method for both powder and oil, while mortality bioassay was conducted by topical application and residual methods for plant oil only. Several plant species showed high biological activity to Callosobruchus sp. Powder of E. aromatica and oil of V. zizanioides caused high oviposition deterrence, while oil of V. zizanioides and E. aromatica caused high mortality.KEY WORDS: Callosobruchus sp., mortality, oviposition deterrence, plant oil, plant powde

Aktivitas Minyak Dan Serbuk Enam Spesies Tumbuhan Terhadap Peneluran Dan Mortalitas Callosobruchus SP. (Coleoptera: Bruchidae)

Storage pests remain one of the main problems in storage. The pest attacks occur not only in the field, but also in storage. Control should be done to maintain the quality of storedproducts. The environmentally friendly measures should be implemented to avoid negative impacts to the environment and human being. The objective of this research was to study the mortality and oviposition deterrence caused by powder and oil of six plant species against Callosobruchus sp. (Coleoptera: Bruchidae). Flowers of Eugenia aromatica, roots of Vetiveria zizanioides, leaves of Pogostemon cablin, seeds of Ricinus communis, seeds of Foeniculum vulgare, and stems of Cymbopogon citratus were air-dried and milled to yield powder. Oil of six plant species were purchased from local market. Oviposition deterrent bioassay was conducted by no-choice method for both powder and oil, while mortality bioassay was conducted by topical application and residual methods for plant oil only. Several plant species showed high biological activity to Callosobruchus sp. Powder of E. aromatica and oil of V. zizanioides caused high oviposition deterrence, while oil of V. zizanioides and E. aromatica caused high mortality

Nitrogen oxide cycle regulates nitric oxide levels and bacterial cell signaling

Nitric oxide (NO) signaling controls various metabolic pathways in bacteria and higher eukaryotes. Cellular enzymes synthesize and detoxify NO; however, a mechanism that controls its cellular homeostasis has not been identified. Here, we found a nitrogen oxide cycle involving nitrate reductase (Nar) and the NO dioxygenase flavohemoglobin (Fhb), that facilitate inter-conversion of nitrate, nitrite, and NO in the actinobacterium Streptomyces coelicolor. This cycle regulates cellular NO levels, bacterial antibiotic production, and morphological differentiation. NO down-regulates Nar and up-regulates Fhb gene expression via the NO-dependent transcriptional factors DevSR and NsrR, respectively, which are involved in the auto-regulation mechanism of intracellular NO levels. Nitrite generated by the NO cycles induces gene expression in neighboring cells, indicating an additional role of the cycle as a producer of a transmittable inter-cellular communication molecule

Aktivitas minyak dan serbuk enam spesies tumbuhan terhadap peneluran dan Mortalitas Callosobruchus sp. (Coleoptera: Bruchidae)

Storage pests remain one of the main problems in storage. The pest attacks occur not only in the field, but also in storage. Control should be done to maintain the quality of storedproducts. The environmentally friendly measures should be implemented to avoid negative impacts to the environment and human being. The objective of this research was to study the mortality and oviposition deterrence caused by powder and oil of six plant species against Callosobruchus sp. (Coleoptera: Bruchidae). Flowers of Eugenia aromatica, roots of Vetiveria zizanioides, leaves of Pogostemon cablin, seeds of Ricinus communis, seeds of Foeniculum vulgare, and stems of Cymbopogon citratus were air-dried and milled to yield powder. Oil of six plant species were purchased from local market. Oviposition deterrent bioassay was conducted by no-choice method for both powder and oil, while mortality bioassay was conducted by topical application and residual methods for plant oil only. Several plant species showed high biological activity to Callosobruchus sp. Powder of E. aromatica and oil of V. zizanioides caused high oviposition deterrence, while oil of V. zizanioides and E. aromatica caused high mortality