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31.
32.
Production of chitinolytic enzymes with Trichoderma longibrachiatum IMI 92027 in solid substrate fermentation
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Thirty Trichoderma strains representing 15 species within the genus have been screened for extracellular production of chitinolytic enzymes in solid substrate fermentation (SSF). T.longibrachiatum IMI 92027 (=ATCC 36838) gave the highest yield (5.0 IU/g dry matter of substrate) after 3 days of fermentation on wheat bran-crude chitin (9:1 mixture) medium. The optimum moisture content (66.7%), chitin content (20%), initial pH of the medium (2-5) and time course (5 d) of SSF were determ… 相似文献
33.
Production of chitinases with Trichoderma harzianun isolates using solid substrate fermentation
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Over forty Trichoderma harzianum isolates have been screened in solid substrate fermentation (SSF)for chitinase production. Strains were isolated from Asian soil and tree bark samples. Identification was performed in Canada and Austria by classical and molecular taxonomical methods.…… 相似文献
34.
Smita JainRafat S. Ahmed Vinod Kumar AroraBasu Dev Banerjee 《Pesticide biochemistry and physiology》2011,100(2):182-186
Triazophos, O,O-diethyl-1-H-1,2,4-triazol-3-yl phosphorothioate, (TZ) is an organophosphorus pesticide which is extensively used in agriculture for controlling insect pests. Except a FAO/WHO report no study has investigated its short-term toxicity with respect to its potential to cause biochemical and histopathological alterations. The present study was designed to identify the effect of TZ at different doses (1.64, 3.2 and 8.2 mg/kg) on the oxidative stress parameters in blood as well as organs involved in xenobiotic metabolism (liver and brain) following chronic exposure for 90 days. Moreover, the study also delineates the effect of TZ on the histo-architecture of these organs. The results indicated a dose dependent induction (p < 0.001) of oxidative stress, as evident by increased malondialdehyde (MDA) level and compromised antioxidant defense including glutathione S transferase (GST) activity, glutathione (GSH) content and ferric reducing ability of plasma (FRAP) in blood, and increased MDA level with concomitantly decreased GSH content in tissues, following chronic exposure to TZ. The ratio of MDA: FRAP in blood was found to be increased following chronic exposure to TZ and may serve as a suitable indicator of severity of oxidative damage. Onset of such biochemical alterations is one of the early adaptive responses to TZ exposure which leads to histopathological alterations in terms of diffuse fatty changes expanding from mid-zonal area to whole lobule in liver. However, increased oxidative stress did not bring any morphological alteration in brain. The present study concludes that induction of oxidative stress, leading to subsequent histopathological alterations in liver, is an important mechanism underlying the TZ induced chronic toxicity. 相似文献
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36.
Mangal Deep Tuti Ramesh Singh Pal Dibakar Mahanta Brij Mohan Pandey Jaideep Kumar Bisht 《Communications in Soil Science and Plant Analysis》2020,51(7):948-962
ABSTRACTLack of crop diversification with suitable vegetable-based cropping system is a major constraint in limiting the productivity and sustainability of north-western Indian sub-Himalayas. To find out a sustainable vegetable-based cropping system in this region, a three year colocasia-based vegetable intensive experiment was conducted at Hawalbagh, Almora, India in a sandy clay loam soil under sub-temperate climatic conditions. Seven colocasia-based vegetable cropping systems along with rice–wheat system were compared under recommended package and practices. The system productivity in terms of colocasia equivalent yield was highest under colocasia–onion–frenchbean (52.38 Mg ha?1) system. Sustainable yield index was highest with colocasia–gardenpea–frenchbean system (0.86). After 3 years, total soil organic carbon (0–5%), available N (2–22%), P (–7% to 14%) and K (3–15%) concentrations were increased in all cropping systems except rice–wheat system, where negative balance of available P (7%) was observed over that of initial soil. Significantly higher soil microbial activity, soil carbohydrate, dehydrogenase, protease, acid and alkaline phosphatases activity were observed under colocasia–onion system. The results suggest that colocasia–onion–frenchbean system with higher productivity improves soil fertility and enhances enzymatic activities. 相似文献
37.
Effluents from low temperature carbonization, high temperature carbonization and producer gas plants in India have been found to contain heavy metals. The level of metals differ from plant to plant and is attributed to operational conditions of carbonization units and quality of coal used. Phenols and organic bases present in the effluent can form organometallic complexes with metal ions present. Such complexes are of environmental significance being toxic, mutagenic and teratogenic in nature. The present investigation showed that LTC wastewater forms complexes with Fe, Cu, and Co, however it does not form any complex with Mn and Zn. 相似文献
38.
Renu Pandey Krishna Kant Dubey Altaf Ahmad Rakshanda Nilofar Rachana Verma Vanita Jain 《Journal of plant nutrition》2015,38(8):1196-1217
Cultivars of Triticum aestivum, T. durum, and Secale cereale were grown at low (2 μM) and sufficient (500 μM) phosphorus (P) under ambient carbon dioxide (380 μmol mol?1; aCO2) and elevated CO2 (700 μmol mol?1, eCO2) to study responses of cereal species in terms of growth and P utilization efficiency (PUE) under P x CO2 interaction. Dry matter accumulation increased under eCO2 with sufficient P. Nevertheless, dry matter accumulated at eCO2 with low-P was similar to that obtained at aCO2 with sufficient P. Leaf area was 43% higher under eCO2 with sufficient P. Significant increase in lateral root density, length and surface area were noted at low-P under eCO2. Phosphorus use efficience (PUE) increased by 59% in response to eCO2 in low-P plants. Thus, eCO2 can partly compensate effect of low-P supply because of improved utilization efficiency. Among cereals, durum wheat was more suitable in terms of PUE under high CO2 and limiting P supply. 相似文献
39.
The effect of a single anthelmintic treatment of cattle during the early dry season was studied. One hundred and sixty-six N'Dama cattle, 1–3 years old, were selected from five herds. There were 65 males and 101 females divided into two groups of 83 animals each. One group was treated with fenbendazole at 7.5 mg/kg body weight by mouth in November 1992; the other group remained as the untreated control. At monthly intervals from November 1992 to April 1993, each animal was weighed and the number of eggs/g of faeces (epg) was determined. The infective larvae (L3) were examined following culture of pooled samples from each group of animals. In April 1993, 6 animals (3 treated and 3 controls) from the herds under study were necropsied. The difference in the weight gains (4.6 kg) of the two groups was highly significant (p<0.0001). The difference in the weight gains and the epg between the treated and control groups was influenced by the age of the animals. Of the treated animals, one contained no nematodes, one contained only 25Oesophagostomum radiatum, and the third contained 25Cooperia L4. The three untreated animals were all infected. It was concluded that the treatment in early dry season, with an anthelmintic effective against both adults and larvae, led to a significant reduction in egg counts, to elimination of adults and hypobiotic larvae and, consequently, to an increase in the body weight gain by the treated animals. 相似文献
40.
At the constant temperature of 25 degrees C and relative humidity (RH) of 84%, the average pre-oviposition period of Hyalomma lusitanicum was 47 days, the oviposition lasted an average of 26 days and the total egg production was an average of 6320 per female. At 16 degrees C the females did not lay eggs at all, but those which survived for 1 year and were transferred thereafter to 25 degrees C and 84% RH laid viable eggs. At 35 degrees C, the oviposition was identical at all levels of RH tested (25, 62 and 93%). At 25 degrees C, the pre-oviposition period was shorter at 93% RH, and the number of eggs laid was fewer at 25% RH. The eggs hatched in 32-40 days, the hatching percentage being lower in batches of eggs laid at the beginning and at the end of the oviposition period. The larval and nymphal moultings were not influenced by the type of host. As the temperature increased, the pre-moult period became shorter. The engorged larvae were more sensitive to the low RH than the engorged nymphs, whose moulting percentage was always greater than 72 in all regimes. Low temperature and high humidity had a favourable effect on the survival of unfed nymphs. The female-to-male ratio was 1:2. Hyalomma lusitanicum always behaved as a 3-host tick. The adults did not engorge on rabbits. The female ticks engorged on calves weighed an average 543 mg. Ticks maintained at 25 degrees C and 84% RH and engorged on calves completed the life cycle in 138-196 days, which does not include the period of chitinization of about 30 days. More than half of this period was spent in egg laying and hatching. 相似文献