BIOASSAY OF SEX PHEROMONES IN THE ARMY CUTWORM, EUXOA AUXILIARIS; THE PALE WESTERN CUTWORM, AGROTIS ORTHOGONIA; AND THE EUXOA TRISTICULA (LEPIDOPTERA: NOCTUIDAE)

1977 ◽  
Vol 109 (3) ◽  
pp. 365-368 ◽  
Author(s):  
D. L. Struble

AbstractEuxoa auxiliaris (Grote) females yielded the largest amount of extractable pheromone after they were stored at least 44 days at 10 °C and then 7 days at room temperature. The males would not respond to the pheromone until they were 28 to 37 days of age and their clearest responses were between 2 and 4 h of the dark cycle. Agrotis orthogonia Morrison females produced pheromone within 1 day after emergence and 2-day-old males responded to it between 5 and 7.5 h of the dark cycle when the olfactometer background light intensity was 0.35 lux. Female Euxoa tristicula Morrison produced pheromone 3 days after emergence and the males responded between 3 to 5 h of the dark cycle.

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Yuying Yang ◽  
Zhiyan Chen ◽  
Xiangqian Lu ◽  
Xiaotao Hao ◽  
Wei Qin

AbstractThe organic magnetoelectric complexes are beneficial for the development on flexible magnetoelectric devices in the future. In this work, we fabricated all organic multiferroic ferromagnetic/ferroelectric complexes to study magnetoelectric coupling at room temperature. Under the stimulus of external magnetic field, the localization of charge inside organic ferromagnets will be enhanced to affect spin–dipole interaction at organic multiferroic interfaces, where overall ferroelectric polarization is tuned to present an organic magnetoelectric coupling. Moreover, the magnetoelectric coupling of the organic ferromagnetic/ferroelectric complex is tightly dependent on incident light intensity. Decreasing light intensity, the dominated interfacial interaction will switch from spin–dipole to dipole–dipole interaction, which leads to the magnetoelectric coefficient changing from positive to negative in organic multiferroic magnetoelectric complexes.


1955 ◽  
Vol 33 (5) ◽  
pp. 821-829 ◽  
Author(s):  
Moyra J. Smith ◽  
Patricia M. Beatty ◽  
J. A. Pinder ◽  
D. J. Le Roy

The mercury (3P1) photosensitized hydrogenation of ethylene has been studied at room temperature as a function of ethylene concentration, mercury concentration, and light intensity. In addition to combination and disproportionation, ethyl radicals have been shown to take part in the reaction[Formula: see text]The conditions favoring this reaction have been established and anomalous values previously found for the ratio of ethane to butane have been explained. The value obtained for the ratio of the rate constants for the disproportionation and combination of ethyl radicals, 0.15 ±.01, is in excellent agreement with the values obtained by other methods. Hexane formation is of some importance at low light intensities and high ethylene concentrations, and is adequately accounted for by the reactions[Formula: see text]


2016 ◽  
Vol 79 (1) ◽  
Author(s):  
Masna Maya SINTA ◽  
Imron RIYADI ◽  
. UMARYONO

AbstractMicroenvironment inside the culture vessel such astemperature, light intensity, relative humidity, and aerationaffect growth and development of plantlets. This experimentwas conducted to determine the effect of different culturevessel closures on microenvironmental conditions inside thevessel and on growth of plantlets of oil palm. Shoots of oilpalm derived from somatic embryos were cultured on DFmedium for eight weeks in transparent culture bottlescovered with five different vessel closures e.i. screw cap withplastic wrap, screw cap, plastic wrap, aluminum foil, andautoclavable plastic. The culture vessels were placed in theculture room with light intensity 20 µmol/m 2 /sec for 12 hoursphotoperiod, at room temperature 26°C. Parametersobserved on plantlet growth were shoot height, biomass freshweight, leaf number, and leaf color grade, while onmicroenvironment were temperature and light intensity. Atthe end of experiment, the volume and fresh weight of theremaining medium were measured to determine evaporationrate of each treatment. Results show that the use of differentculture vessel closures affected the microenvironment insidethe vessel, the volume of the remaining medium, and thegrowth of the plantlets. The closure increased thetemperature by 1.6 – 2.6°C and decreased the light intensityby 1.7 – 8.7 µmol/m 2 /sec inside the culture vessels dependson the culture vessel closures. Culture vessels with aluminumfoil closure had the lowest temperature (28.9°C) and thelowest light intensity (10.8 µmol/m 2 /sec) gave the best resultin the growth of the plantlets. Better plantlets growth wasalso observed in the culture vessel with autoclavable plasticclosure that less expensive, therefore it can be used as analternative vessel closure for the growth of oil palm plantlets.AbstrakLingkungan mikro di dalam botol kultur seperti suhu,intensitas cahaya, kelembaban nisbi dan aerasi mem-pengaruhi pertumbuhan dan perkembangan planlet.Penelitian ini dilakukan untuk mengetahui pengaruhpenggunaan penutup botol kultur yang berbeda terhadapkondisi lingkungan mikro di dalam botol kultur danpertumbuhan planlet kelapa sawit. Planlet kelapa sawit asalembrio somatik dikulturkan dalam botol kultur bening berisimedium DF selama delapan minggu dan ditutup mengguna-kan lima jenis penutup botol yang berbeda yaitu tutup ulirdengan plastik wrap, tutup ulir, plastik wrap, aluminium foildan plastik tahan diautoklaf. Kultur diletakkan dalam ruangkultur, di bawah lampu TL dengan intensitas cahaya20 µmol/m 2 /detik dan suhu ruang 26 o C. Parameterpertumbuhan planlet yang diamati adalah tinggi planlet,bobot basah, jumlah daun dan kelas warna daun, sedangkanlingkungan mikro adalah suhu dan intensitas cahaya. Padaakhir eksperimen, volume dan bobot basah medium yangtersisa diukur untuk mengetahui tingkat penguapan padasetiap perlakuan. Hasil penelitian menunjukkan bahwapenggunaan penutup botol yang berbeda berpengaruhterhadap lingkungan mikro, volume medium tersisa dalambotol kultur dan pertumbuhan planlet. Penutup botolmeningkatkan suhu 1,6 – 2,6 o C dan menurunkan intensitascahaya 1,7 – 8,7 µmol/m 2 /detik di dalam botol tergantungpada jenis penutup botol yang digunakan. Botol kulturdengan penutup berbahan aluminium foil mempunyaiintensitas cahaya terendah (10,8 µmol/m 2 /detik) dan suhuterendah (28,9 o C) memberikan hasil terbaik pada pembesaranplanlet kelapa sawit. Pertumbuhan planlet yang baik jugaterdapat pada botol kultur dengan penutup plastik tahandiautoklaf yang lebih murah, sehingga penutup ini dapatdigunakan sebagai pilihan untuk pembesaran planlet kelapasawit.


2016 ◽  
Vol 79 (1) ◽  
Author(s):  
Masna Maya SINTA ◽  
Imron RIYADI ◽  
. UMARYONO

AbstractMicroenvironment inside the culture vessel such astemperature, light intensity, relative humidity, and aerationaffect growth and development of plantlets. This experimentwas conducted to determine the effect of different culturevessel closures on microenvironmental conditions inside thevessel and on growth of plantlets of oil palm. Shoots of oilpalm derived from somatic embryos were cultured on DFmedium for eight weeks in transparent culture bottlescovered with five different vessel closures e.i. screw cap withplastic wrap, screw cap, plastic wrap, aluminum foil, andautoclavable plastic. The culture vessels were placed in theculture room with light intensity 20 µmol/m 2 /sec for 12 hoursphotoperiod, at room temperature 26°C. Parametersobserved on plantlet growth were shoot height, biomass freshweight, leaf number, and leaf color grade, while onmicroenvironment were temperature and light intensity. Atthe end of experiment, the volume and fresh weight of theremaining medium were measured to determine evaporationrate of each treatment. Results show that the use of differentculture vessel closures affected the microenvironment insidethe vessel, the volume of the remaining medium, and thegrowth of the plantlets. The closure increased thetemperature by 1.6 – 2.6°C and decreased the light intensityby 1.7 – 8.7 µmol/m 2 /sec inside the culture vessels dependson the culture vessel closures. Culture vessels with aluminumfoil closure had the lowest temperature (28.9°C) and thelowest light intensity (10.8 µmol/m 2 /sec) gave the best resultin the growth of the plantlets. Better plantlets growth wasalso observed in the culture vessel with autoclavable plasticclosure that less expensive, therefore it can be used as analternative vessel closure for the growth of oil palm plantlets.AbstrakLingkungan mikro di dalam botol kultur seperti suhu,intensitas cahaya, kelembaban nisbi dan aerasi mem-pengaruhi pertumbuhan dan perkembangan planlet.Penelitian ini dilakukan untuk mengetahui pengaruhpenggunaan penutup botol kultur yang berbeda terhadapkondisi lingkungan mikro di dalam botol kultur danpertumbuhan planlet kelapa sawit. Planlet kelapa sawit asalembrio somatik dikulturkan dalam botol kultur bening berisimedium DF selama delapan minggu dan ditutup mengguna-kan lima jenis penutup botol yang berbeda yaitu tutup ulirdengan plastik wrap, tutup ulir, plastik wrap, aluminium foildan plastik tahan diautoklaf. Kultur diletakkan dalam ruangkultur, di bawah lampu TL dengan intensitas cahaya20 µmol/m 2 /detik dan suhu ruang 26 o C. Parameterpertumbuhan planlet yang diamati adalah tinggi planlet,bobot basah, jumlah daun dan kelas warna daun, sedangkanlingkungan mikro adalah suhu dan intensitas cahaya. Padaakhir eksperimen, volume dan bobot basah medium yangtersisa diukur untuk mengetahui tingkat penguapan padasetiap perlakuan. Hasil penelitian menunjukkan bahwapenggunaan penutup botol yang berbeda berpengaruhterhadap lingkungan mikro, volume medium tersisa dalambotol kultur dan pertumbuhan planlet. Penutup botolmeningkatkan suhu 1,6 – 2,6 o C dan menurunkan intensitascahaya 1,7 – 8,7 µmol/m 2 /detik di dalam botol tergantungpada jenis penutup botol yang digunakan. Botol kulturdengan penutup berbahan aluminium foil mempunyaiintensitas cahaya terendah (10,8 µmol/m 2 /detik) dan suhuterendah (28,9 o C) memberikan hasil terbaik pada pembesaranplanlet kelapa sawit. Pertumbuhan planlet yang baik jugaterdapat pada botol kultur dengan penutup plastik tahandiautoklaf yang lebih murah, sehingga penutup ini dapatdigunakan sebagai pilihan untuk pembesaran planlet kelapasawit.


2021 ◽  
Vol 13 (1) ◽  
pp. 178-182
Author(s):  
Eknath Shendge ◽  
Bapurao Khaire ◽  
Ramrao Chavan

Among different fruit piercing moths, the genus Othreis are the most harmful, causing widespread damage to pomegranate, citrus and mango fruits causing fruit fall in tropical and subtropical countries. The present communication deals with the study on the biology of  Othreis materna (L) from egg to adult’s death which was carried out  at room temperature of the laboratory  to investigate the delicate and vulnerable stages of its life cycle. The life cycle of the moth was completed within 45-61 days, with an average 55.03 days in case of male and within 47-63 days with an average 57.07±4.92 in case of female. Eggs hatching started at night or early in the morning and duration of hatching was 2.72 days. The eggs measured were about 0.95 to 0.03 mm in diameter. The freshly emerged first instar larvae were light yellowish coloured and translucent. The first instar larvae were very active after hatching and they moved 4 to 6 feet for searching the food. The larvae were fed with the leaves of Tinospora cordifolia (Giloy or Guduchi). The total larval duration in days from first, second, third, fourth and fifth instar varied from 2.12±0.01, 1.81±0.05, 2.87±0.02, 3.90±0.11, 4.74±0.38 in days respectively and total larval period was 15.44±0.57. Pupae were dark brown in colour and total pupation period was of 13.81±0.12 days and total adult duration for male and female was 23.08±0.70 and 25.20±0.66 days respectively. The adult of O. materna was bright orange in colour and of medium size. The male was small than the female. This is first study of this type from Marathwada, which will help to trace the vulnerable and delicate stage of the life cycle of this O. materna.


2012 ◽  
Vol 36 (1) ◽  
pp. 97-107 ◽  
Author(s):  
Mehnaz Sharmin ◽  
Shamima Choudhury ◽  
Nasrin Akhtar ◽  
Tahmina Begum

Electrical properties such as electrical resistivity, Hall coefficient, Hall mobility, carrier concentration of p-type GaAs samples were studied at room temperature (300 K). Resistivity was  found to be of the order of 5.6 × 10-3?-cm. The Hall coefficient (RH) was calculated to be 7.69 × 10-1cm3/C and Hall mobility (?H) was found to be 131cm2/V-s at room temperature from Hall effect   measurements. Carrier concentration was estimated to be 8.12 × 1018/cm3 and the Fermi level was calculated directly from carrier density data which was 0.33 eV. Photoconductivity measurements  were carried on by varying sample current, light intensity and temperature at constant chopping     frequency 45.60 Hz in all the cases mentioned above. It was observed that within the range of sample current 0.1 - 0.25mA photoconductivity remains almost constant at room temperature 300K and it was found to be varying non-linearly with light intensity within the range 37 - 12780 lux. Photoconductivity was observed to be increasing linearly with temperature between 308 and 428 K. Absorption coefficient (?) of the samples has been studied with variation of wavelength (300 -  2500 nm). The value of optical band gap energy was calculated between 1.34 and 1.41eV for the material from the graph of (?h?)2 plotted against photon energy. The value of lattice parameter (a) was found to be 5.651 by implying X-ray diffraction method (XRD).DOI: http://dx.doi.org/10.3329/jbas.v36i1.10926Journal of Bangladesh Academy of Sciences, Vol. 36, No. 1, 97-107, 2012 


Sign in / Sign up

Export Citation Format

Share Document