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1.
Effect of soil solarization on nodulation,infection by mycorrhizal fungi and yield of cowpea 总被引:1,自引:1,他引:0
S. K. Nair C. K. Peethambaran D. Geetha Kamala Nayar K. I. Wilson 《Plant and Soil》1990,125(1):153-154
Solarization of soil was found beneficial for plant growth in cowpea under field conditions. Root nodulation, infection by
mycorrhizal fungi and yield were higher in plants grown in solarized soil. These increases were to the extent of 104.7, 20.0
and 23.7 per cent respectively when compared to control treatment without solarization. 相似文献
2.
The responses of the field mouse Mus booduga to shifts in schedules of LD cycles were monitored and the results were interpreted with the help of a PRC constructed for the same species. The results reveal that, M. booduga reentrained faster with a lesser number of transients after delay shifts than advance shifts, thus exhibiting “asymmetry effect.” A positive correlation was observed between the number of transients and the number of hours of shift. In most of the shifts, the sign of the transients (negative for delaying transients and positive for advancing transients) coincided with the direction of the shift. Interestingly, 11 and 12 h of advance shifting resulted in delaying transients. An 11-h advance shift can also be interpreted as a 13-h delay. Reentrainment through delaying transients is faster as compared to reentrainment through advancing transients. Thus, this animal might have taken a “shorter route,” as proved by the fact that an 11-h advance shift has evoked delaying transients. But a 13-h advance shift evoked only advancing transients. This prompts us to speculate that there may be a “phase jump” in M. booduga. Further, irrespective of whether L or D has been doubled in a 12-h shift, both evoked only delaying transients. 相似文献
3.
4.
The species of flies breeding in bovine manure, their parasites and predators as well as other associated arthropods in 3
localities in and near Bangalore are recoreded. The flies areMusca domestica L.,Musca pattoni
Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R.-D.,Sepsis nitens
Wiedemann,Sphaerocera scabricula
Hal, andLeptocera (Coproica) hirtula
Rondani. Four species of hymenopterous pupal parasites of these flies have been obtained:Spalangia cameroni
Perkins from pupae ofM. domestica, M. pattoni, S. calcitrans, P. aenea andP. demandata; Spalangia endius
Walker from pupae ofM. domestica, M. pattoni andS. calcitrans; Spalangia nigroaenea
Curtis from pupae ofM. domestica andS. calcitrans; andDirhinus trichiophthalmus
Masi from pupae ofSargus metallinus F. Percentage parasitism of fly puparia in field samples was noted. Four species ofHister andAleochara puberula
Klug feeding on various immature stages ofM. domestica, 2 species of scarabaeid beetles, 2 species of ants and a pseudoscorpion were also found in the manure. The importance of
biotic regulatory factors in the control of flies is discussed.
Paper presented at the seminar on utilization of farm wastes for rural industrial growth, National Dairy Research Institute, Bangalore, 31 st December, 1975.
This paper is published with the permission of the Director-General, Indian Council of Medical Research, New Delhi 相似文献
Résumé Dans 3 localités de Bangalore ou proches de cette ville, on a inventorié les espèces de mouches vivant dans le fumier de vache, leurs parasites et prédateurs ainsi que d'autres arthropodes associés. Les mouches récoltées sont:Musca domestica L.,Musca pattoni Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R-D.,Sepsis nitens Wiedemann,Sphaerocera scabricula Hal. etLeptocera (Coproica) hirtula Rondani. Quatre espèces d'hyménoptères parasites des pupes ont été obtenues de ces mouches:Spalangia cameroni Perkins deM. domestica, M. pattoni, S. calcitrans, P. aenea etP. demandata: Spalangia endius Walker deM. domestica, M. pattoni etS. calcitrans, P. aenea etP. demandata; Spalangia endius Walker trans; etDirhinus trichiophthalmus Masi deSargus metallinus F. On a noté le taux de parasitisme des nymphes dans les conditions naturelles. Quatre espèces deHister etAleochara puberula Klug s'attaquant aux divers stades non imaginaux deM. domestica, 2 espèces de scarabeides, 2 espèces de fourmis et un pseudoscorpion ont été également trouvés dans le fumier. L'importance de ces facteurs biotiques dans la régulation des populations de mouches est discutée.
Paper presented at the seminar on utilization of farm wastes for rural industrial growth, National Dairy Research Institute, Bangalore, 31 st December, 1975.
This paper is published with the permission of the Director-General, Indian Council of Medical Research, New Delhi 相似文献
5.
Inhibition of hepatitis delta virus RNA editing by short inhibitory RNA-mediated knockdown of ADAR1 but not ADAR2 expression
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Hepatitis delta virus (HDV) requires host RNA editing at the viral RNA amber/W site. Of the two host genes responsible for RNA editing via deamination of adenosines in double-stranded RNAs, short inhibitory RNA-mediated knockdown of host ADAR1 expression but not that of ADAR2 led to decreased HDV amber/W editing and virus production. Despite substantial sequence and structural variation among the amber/W sites of the three HDV genotypes, ADAR1a was primarily responsible for editing all three. We conclude that ADAR1 is primarily responsible for editing HDV RNA at the amber/W site during HDV infection. 相似文献
6.
Duncan J. Berger Elsa Lger Geetha Sankaranarayanan Mariama Sne Nicolas D. Diouf Muriel Rabone Aidan Emery Fiona Allan James A. Cotton Matthew Berriman Joanne P. Webster 《PLoS pathogens》2022,18(8)
Hybridization between different species of parasites is increasingly being recognised as a major public and veterinary health concern at the interface of infectious diseases biology, evolution, epidemiology and ultimately control. Recent research has revealed that viable hybrids and introgressed lineages between Schistosoma spp. are prevalent across Africa and beyond, including those with zoonotic potential. However, it remains unclear whether these hybrid lineages represent recent hybridization events, suggesting hybridization is ongoing, and/or whether they represent introgressed lineages derived from ancient hybridization events. In human schistosomiasis, investigation is hampered by the inaccessibility of adult-stage worms due to their intravascular location, an issue which can be circumvented by post-mortem of livestock at abattoirs for Schistosoma spp. of known zoonotic potential. To characterise the composition of naturally-occurring schistosome hybrids, we performed whole-genome sequencing of 21 natural livestock infective schistosome isolates. To facilitate this, we also assembled a de novo chromosomal-scale draft assembly of Schistosoma curassoni. Genomic analyses identified isolates of S. bovis, S. curassoni and hybrids between the two species, all of which were early generation hybrids with multiple generations found within the same host. These results show that hybridization is an ongoing process within natural populations with the potential to further challenge elimination efforts against schistosomiasis. 相似文献
7.
Effect of doxorubicin on heart mitochondrial enzymes was studied in rats with or without the administration of alpha-tocopherol. Rats were treated with doxorubicin 2.5 mg/kg, ip body wt once a week for 8 weeks. Alpha-tocopherol was co-administered orally for 2 months (400 mg/kg body wt daily). TCA cycle enzyme, NADH-dehydrogenase, cytochrome-C-oxidase and Na+,K(+)-ATPase activities were found to be decreased in doxorubicin treatment. A significant decrease in protease activity was observed with a concomitant increase in mitochondrial protein level. Mitochondrial lipid peroxide level was found to be increased with a decrease in thiol content. Alpha-tocopherol co-administration was found to maintain the mitochondrial enzyme activities as well as the thiol content. The results are discussed with reference to the antioxidant nature of alpha-tocopherol. 相似文献
8.
Anju Das K. M. Geetha Iswar Hazarika 《International journal of peptide research and therapeutics》2020,26(3):1211-1221
Pathogenesis of diabetes mellitus involves scores of different factors, out of which Glucagon like factor-1 (GLP-1) plays a foremost role. GLP-1 is a pepti 相似文献
9.
Native species’ response to the presence of invasive species is context specific. This response cannot be studied in isolation from the prevailing environmental stresses in invaded habitats such as seasonal drought. We investigated the combined effects of an invasive shrub Lantana camara L. (lantana), seasonal rainfall and species’ microsite preferences on the growth and survival of 1,105 naturally established seedlings of native trees and shrubs in a seasonally dry tropical forest. Individuals were followed from April 2008 to February 2010, and growth and survival measured in relation to lantana density, seasonality of rainfall and species characteristics in a 50-ha permanent forest plot located in Mudumalai, southern India. We used a mixed effects modelling approach to examine seedling growth and generalized linear models to examine seedling survival. The overall relative height growth rate of established seedlings was found to be very low irrespective of the presence or absence of dense lantana. 22-month growth rate of dry forest species was lower under dense lantana while moist forest species were not affected by the presence of lantana thickets. 4-month growth rates of all species increased with increasing inter-census rainfall. Community results may be influenced by responses of the most abundant species, Catunaregam spinosa, whose growth rates were always lower under dense lantana. Overall seedling survival was high, increased with increasing rainfall and was higher for species with dry forest preference than for species with moist forest preference. The high survival rates of naturally established seedlings combined with their basal sprouting ability in this forest could enable the persistence of woody species in the face of invasive species. 相似文献
10.
Gerta Fleissner Kirsten Schuchardt Dietrich Neumann Geetha Bali Gerald Falkenberg Guenther Fleissner 《Chronobiology international》2013,30(1):17-30
Living in the tidal zones of the sea requires synchronization with the dominant environmental influences of tidal, solar, and lunar periodicity. Endogenous clocks anticipate those geoclimatic changes and control the respective rhythms of vital functions. But the underlying mechanisms are only partly understood. While the circadian clocks in animals are investigated employing neurobiological, molecular, and genetic approaches, clocks with a lunar periodicity have been studied with reference to development and behavior only. Sites of their pacemakers, zeitgeber receptors, and coupled endocrine components are unknown. Here, a lunar‐rhythmic change of shielding pigment transparency in the larval ocelli of the intertidal midge Clunio marinus is demonstrated for the first time as a possible access to the neurobiology of lunar timing mechanisms. We studied third instar larvae (Vigo strain) throughout the lunar cycle by light‐ and electron-microscopy as well as by x‐ray fluorescence analysis for the identification of the pigment. Moonlight detection is a prerequisite for photic synchronization of the lunar clock. The larval ocelli of Clunio putatively may function as moonlight receptors and are also controlled by the circalunar clock itself, hence being primary candidates for tracing input and output pathways of the lunar pacemaker. Additionally, the demonstration of a reversible optical change of shielding pigment transparency in Clunio is a novel finding, not reported so far in any other animal species, and reveals a mechanism to enhance photosensitivity under the condition of very dim light. It represents a remarkable change of a sense organ from an imaging device to a radiometer. Its restriction to the developmental stage susceptible to lunar timing elucidates a unique sensory strategy evolved at the level of sensory input. It also raises basic questions about the biochemistry of optically active pigments, like melanin, and their intracellular control. 相似文献