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81.
The diets of the wolf Canis lupus, red fox Vulpes vulpes and raccoon dog Nyctereutes ussurienusis Matschie were studied in the grassland of eastern Inner Mongolia from August to October in 2007 and from March to July in 2008. Feces were collected from dens and latrines. The frequency of occurrence and the dry weight of the remains of each food item in the feces were calculated. Livestock (50.65% frequency of occurrence) constituted the bulk of the wolf diet, while small rodents (76.31% frequency of occurrence) were most frequently eaten by the foxes. Small rodents (22.69% frequency of occurrence) were important to the raccoon dogs but they also frequently consumed birds (39.81% frequency of occurrence) and insects (26.39% frequency of occurrence). The wolf was the most omnivorous and the red fox was the least omnivorous of these three kinds of canidae according to the diversity index. The food niches of the wolf and the red fox overlapped more than that of the raccoon dog and other species. These three kinds of canidae shared many resources and consequently competition occurred to them. However, their diets also differed to some extent which helped them to avoid competition. Furthermore, raccoon dogs were dormant in winter when food was scarce, which may be the reason why all these species could coexist in a rather unproductive grassland. 相似文献
82.
83.
Biodegradation of pyridine and α-picoline (2-methyl pyridine) by Pseudomonas
pseudoalcaligenes-KPN and Nocardia sp. isolated from garden soil were investigated in batch culture experiments. Pyridine and α-picoline (50–200 mg L−1) were used as sole source of carbon and energy in the investigation. The kinetic constants were evaluated for pyridine and
α-picoline degradation under optimized nutritional (C, N, P) and environmental (pH, temperature) conditions. The values of
bio-kinetic constant obtained in the present investigation indicate the usefulness of both the cultures for treatment of waste
containing pyridine and its derivatives. 相似文献
84.
85.
Pandey GK Pandey A Reddy VS Deswal R Bhattacharya A Upadhyaya KC Sopory SK 《Journal of biosciences》2007,32(2):251-260
Entamoeba histolytica contains a novel calcium-binding protein like calmodulin, which was discovered earlier, and we have reported the presence
of its homologue(s) and a dependent protein kinase in plants. To understand the functions of these in plants, a cDNA encoding
a calcium-binding protein isolated from Entamoeba histolytica (EhCaBP) was cloned into vector pBI121 in antisense orientation and transgenic tobacco plants were raised. These plants showed
variation in several phenotypic characters, of which two distinct features, more greenness and leaf thickness, were inherited
in subsequent generations. The increase in the level of total chlorophyll in different plants ranged from 60% to 70%. There
was no major change in chloroplast structure and in the protein level of D1, D2, LHCP and RuBP carboxylase. These morphological
changes were not seen in antisense calmodulin transgenic tobacco plants, nor was the calmodulin level altered in EhCaBP antisense
plants.
The results of this paper have been granted US Patent No. 6,791,009. 相似文献
86.
Stress-induced degradation of D1 protein and its photoprotection by DCPIP in isolated thylakoid membranes of barley leaf 总被引:1,自引:0,他引:1
Effects of various stress treatments such as NaCl, hydrogen peroxide, hydroxyl free radical, and high irradiance (HI, 1 000
μmol m−2 s−1) on the photosystem (PS) 2 mediated electron transport rate and the degradation of D1 protein in the thylakoid membranes
of barley were studied. The applied stresses caused significant reduction in the PS 2-mediated electron transport and a degradation
of D1 protein that was highest during the HI-treatment. Presence of 2,6-dichlorophenol indophenol (DCPIP), which is an artificial
electron acceptor from water, significantly minimizes the HI-induced deleterious effect on the PS 2-mediated electron transport
rate, disarrangement of PS machinery, and degradation of the D1 protein. HI in the absence of an acceptor resulted in production
of reactive oxygen species due to electron transfer to oxygen. 相似文献
87.
Ajay Kumar D.M. Pandey Thomson Abraham Jacob Mathew Padma Ramachandran 《Archives Of Phytopathology And Plant Protection》2013,46(6):710-720
Tapping panel dryness (TPD) syndrome affecting rubber tree (Hevea brasiliensis) is known to reduce natural latex production. Its aetiology remains ambiguous despite long years of research. A low molecular weight RNA similar to viroid RNA was isolated from TPD-affected samples of rubber trees. In the present study, a modified return-polyacrylamide gel electrophoresis procedure was standardised. The viroid-like low molecular weight (LMW) RNA was found associated with leaf, bark and root tissues and rubber seedlings. The technique was employed to detect LMW RNA in different clones of rubber planted in different locations and in bud-grafted plants. The LMW RNA isolated from TPD-affected trees was found infectious on seedlings of tomato cv Pusa Ruby. The LMW RNA was reisolated from symptomatic tomato leaves but not from control plants. This is for the first time that a biotic agent, a viroid RNA, is found consistently associated with the syndrome. The technology developed can be useful to demonstrate the onset of TPD in untapped trees in the absence of other methods such as nucleic acid hybridisation. 相似文献
88.
89.
Use of chemical activator for the management of root-knot disease in medicinal and aromatic plants can become an attractive alternative to traditionally used nematicides. Large numbers of chemical molecules are present in the plants and are involved in the induction of different types of proteins. The purpose of our research study is to explore the possibilities of resistance factors that are inherent in the plant by treating them with few chemical activators to activate against root-knot nematode infection. Efforts were made to achieve a satisfactory suppression of root-knot nematode, Meloidogyne incognita, a serious menace to successful cultivation of chamomile, Matricaria recutita L. Rauch (syn. Matricaria chamomilla L. Fain. Asteraceae) causing root-knot disease through use of different chemical activators. Here we examined selected groups of resistance activator viz. Isonicotinamide, 2-chloronicotinic acid, 5-nitrosalicylic acid, 4-chlorosalicylic acid, DL-2 aminobutyric acid, 2-aminobutyric acid, O-acetylsalicylic acid, 4-amino salicylic acid, salicylic acid and these were used as soil drench using 3 week old seedlings transplanted to root-knot nematode infested pots. Maximum reduction in root-knot severity and nematode population occurred with 4-chlorosalicylic acid, O-acetyl salicylic acid, 2-chloronicotinic acid and gave significant flower yield advantages. Present experiment suggests a strong possibility of these activators in integrated management for protection against plant parasitic nematodes. 相似文献
90.
Pradyot Bhattacharya Smriti Ghosh Sarfaraz Ahmad Ejazi Mehebubar Rahaman Krishna Pandey Vidya Nand Ravi Das Pradeep Das Rama Prosad Goswami Bibhuti Saha Nahid Ali 《PLoS neglected tropical diseases》2016,10(2)