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41.
Species composition, biomass, and productivity patterns of three types of traditional agroforestry systems, namely, agrisilvicultural,
agrihorticultural, and agrihortisilvicultural, commonly practiced in the western Himalaya, were studied. Species composition
in the systems varied depending upon the size of the land holdings, and the basic requirements of the farmer. Among three
systems agrihortisilvicultural was highly diverse in vegetation, with as many as 13 tree and 5 agricultural crops mixed together.
This system showed the highest productivity up to 25.8 t ha−1 yr−1, out of which 68 percent was contributed by the trees and the remainder by the annuals. Agrisilvicultural system having predominantly
annuals had the lowest productivity of 20.4 t ha−1 yr−1 with only 27 percent contribution by the trees. Total aboveground biomass in agrihortisilvicultural or agrihorticultural
system was around 48 t ha−1 and it was about 2-fold higher than agrisilvicultural system. In fodder trees, a significant percentage of annual production,
up to 48 percent, was allocated in current twigs, while in horticultural trees a major portion, up to 63 percent was partioned
towards fruits. Implications of the results have been discussed in context with the growing problems of fuel, fodder, and
packaging material in the western Himalaya. 相似文献
42.
H. Ji A. D. Om T. Yoshimatsu T. Umino H. Nakagawa S. Sakamoto 《Fish physiology and biochemistry》2010,36(3):749-755
To assess the effect of dietary ascorbate on lipid metabolism, 1-year black sea bream (Acanthopagrus schlegelii) were reared on a casein-based purified diet and an ascorbate fortified diet (1,100 mg of l-ascorbyl-2- monophosphate-Mg/kg diet). The fortified ascorbate was effectively incorporated into the fish body and elevated
muscle carnitine content. Fortifications of dietary ascorbate depressed activities of glucose-6-phosphate dehydrogenase and
NADP-isocitrate dehydrogenase as lipogenic enzymes in the hepatopancreas and intraperitoneal fat body. Starvation after feeding
experiment activated carnitine palmitoyltransferase as a lipolysis enzyme in the hepatopancreas in both control and vitamin
C(VC) groups, while the lipolysis activity was significantly higher in VC group. These results confirmed that dietary ascorbate
depressed lipogenesis and activated lipolysis, i.e., influenced the lipid metabolism of black sea bream. 相似文献
43.
Anjali Soni Anil Kumar Dubey Ankit Gupta Radha Mohan Sharma Om Prakash Awasthi Chellapilla Bharadwaj Nimisha Sharma 《Plant Breeding》2019,138(3):368-376
In citrus, development of new hybrids is difficult due to failure of the germination of zygotic embryos. Hence, this study was conducted to standardize embryo age and media for maximizing the germination and subsequent seedling growth in sour orange × Sacaton citrumelo crosses followed by the identification of simple sequence repeats (SSR) markers for distinguishing the hybrids. A factorial experiment in complete randomized design was conducted with two each embryo age (110–120 and 130–140 days after pollination) and culture media (G‐B5 supplemented with 1.5 mg/L GA3 plus malt extract and G‐B5 plus malt extract) for in vitro embryo culture of sour orange × Sacaton citrumelo progenies. Older embryos germinated well in both media, though highest on M1 medium (100%). In fact, M1 medium gave higher plantlet survival in both age groups. The seedling growth of older embryos had highest root length (37.80 mm) and shoot length (24.20 mm) in M1 medium at 60 days after inoculation (DAI). Three SSR markers (TAA45, CAC15 and CAC39) showed polymorphism between female and male parents and were able to identify their hybrids. 相似文献
44.
Effects of shade on arbuscular mycorrhizal colonization and growth of crops and tree seedlings in Central India 总被引:1,自引:0,他引:1
Ashok Shukla Anil Kumar Anuradha Jha Om Prakash Chaturvedi Rajendra Prasad Ajit Gupta 《Agroforestry Systems》2009,76(1):95-109
The study was conducted to investigate the effects of different light intensities (25, 50, 67, and 100% of full sun [open])
on arbuscular mycorrhizal (AM) colonization and growth of two intercrops (a rainy season crop, Phaseolus mungo Roxb. var. PU-35 and a winter crop, Triticum aestivum L. var. WH-147) and seedlings of two multipurpose tree species (Eucalyptus tereticornis Sm. [Clone C-7, ITC, Bhadrachalam] and Albizia procera Benth.) of Central India. The results showed that various plant growth parameters viz., shoot length, dry weight and phosphorus
(P) uptake were adversely affected by low light intensity. Inoculations with AM fungi (Acaulospora scrobiculata Trappe, Glomus intraradix Schenck & Smith and an unidentified Glomus species) increased the plant growth on account of all measured parameters under tested light conditions. Mycorrhizal efficiency
of different AM fungi varied in narrow range. AM inoculants were more efficient at higher light intensity in above mentioned
plant species, except wheat. Data on colonization of P. mungo, T. aestivum, E. tereticornis and A. procera showed that formation of arbuscules, vesicles and sporocarp was delayed by lower light intensity. Colonization index of host
roots and spore counts increased with increase in light intensity during successive months after inoculation. Data on effect
of light regimes on microclimate of net house showed that lux meter reading decreased as per grades of shading nets used during
both rainy and winter seasons. With increase in light intensity, ambient temperature, soil surface temperature and sub surface
temperature at 15 cm depth increased, except that the ambient and soil surface temperature in control (open) were slightly
lower than net house observations during January and February. Value of ambient temperature varied in narrow range, with in
treatments as compared to soil surface and sub soil surface temperature at 15 cm depth. Soil surface temperature at 25% of
full sunlight was less than respective control values by 2–11°C and sub soil temperature at 15 cm depth was less by 4–12°C.
The values of different microclimate parameters varied in narrower range during winter season as compared to rainy season.
While ranking the importance of two factors studied—light and AM fungi—for their effect on the growth and P uptake by different
plant species, inoculations with AM fungi came in the first place (explained 50–82% variation) and light substantially increased
the values of R
2 in stepwise regression analysis (forward selection). The results suggest that AM inoculation may enhance the growth and P
uptake of intercrops under tree shade and the tree canopy management is likely to increase the efficiency of AM inoculants
in agroforestry systems. Use of excessive shading (25% of full sun or more) in nurseries may be avoided and PAR (photosynthetically
active radiation) lamps may be used to increase growth and colonization index of tree seedlings. 相似文献
45.
Serum electrolytes, minerals, blood biochemical and plasma enzymes were studied in heat exposed buffalo heifers supplemented with yeast powder in feed to alleviate the adverse effects of heat stress. Eighteen healthy Murrah buffalo heifers (270-280) kg were divided into three groups. Animals of group I were kept in shed and served as control, while group II and group III were exposed in a psychrometric chamber at 40°C for 4?hrs daily for 16?days continuously. The animals in group III were also supplemented with yeast powder at 10?g per animal per day. The serum sodium, potassium and chloride levels decreased significantly (P?0.05) in group II and their levels tended to be maintained in group III. Serum calcium, magnesium, phosphorus, glucose and total cholesterol concentration decreased (P?0.05) significantly whereas total protein increased in group II due to heat stress. The levels of these minerals tended to be normal in group III. The plasma concentration of SGOT and SGPT increased significantly (P?0.05), whereas the concentration of plasma alkaline phosphatase and acid phosphatase decreased due to thermal exposure. The levels of these enzymes tended to be normal in group III. The results indicated significant deviations in blood biochemical due to thermal stress and their levels tended to be normal in yeast supplemented group of buffalo heifers. 相似文献
46.
Subramaniam Gopalakrishnan R. Mahender Kumar Pagidi Humayun V. Srinivas B. Ratna Kumari R. Vijayabharathi Amit Singh K. Surekha Ch. Padmavathi N. Somashekar P. Raghuveer Rao P. C. Latha L. V. Subba Rao V. R. Babu B. C. Viraktamath V. Vinod Goud N. Loganandhan Biksham Gujja Om Rupela 《Paddy and Water Environment》2014,12(1):79-87
Field experiments were conducted at DRR farm located at ICRISAT, Patancheru, in sandy clay loam soils during four seasons, Kharif 2008, Rabi 2008–2009, Kharif 2009 and Rabi 2009–2010, to investigate growth parameters, water-saving potential, root characteristics, chemical, biological, and microbial properties of rhizosphere soil, and grain yield of rice (Oryza sativa L.) by comparing the plants grown with system of rice intensification (SRI) methods, with organic or organic + inorganic fertilization, against current recommended best management practices (BMP). All the growth parameters including plant height, effective tillers (10–45 %), panicle length, dry matter, root dry weight (24–57 %), and root volume (10–66 %) were found to be significantly higher with in SRI-organic + inorganic over BMP. With SRI-organic fertilization, growth parameters showed inconsistent results; however, root dry weight (3–77 %) and root volume (31–162 %) were found significantly superior compared to BMP. Grain yield was found significantly higher in SRI-organic + inorganic (12–23 and 4–35 % in the Kharif and Rabi seasons, respectively), while with SRI-organic management, yield was found higher (4–34 %) only in the Rabi seasons compared to BMP. An average of 31 and 37 % of irrigation water were saved during Kharif and Rabi seasons, respectively, with both SRI methods of rice cultivation compared to BMP. Further, total nitrogen, organic carbon%, soil dehydrogenase, microbial biomass carbon, total bacteria, fungi, and actinomycetes were found higher in the two SRI plots in comparison to BMP. It is concluded that SRI practices create favorable conditions for beneficial soil microbes to prosper, save irrigation water, and increase grain yield. 相似文献
47.
Singh Mahendra Babanna Sridhar K. Kumar Dhiraj Dwivedi Ragunandhan P. Dev Inder Kumar Anil Tewari Rama Kant Chaturvedi Om Prakash Dagar Jagdish Chandra 《Agroforestry Systems》2021,95(5):977-993
Agroforestry Systems - This article presents a methodology for the valuation of agroforestry with respect to fuelwood supply for cooking and its opportunity cost. The share of fuelwood consumption... 相似文献
48.
A fluorescence polarization assay for the detection of antibodies to Mycobacterium bovis in cattle sera 总被引:4,自引:0,他引:4
Surujballi OP Romanowska A Sugden EA Turcotte C Jolley ME 《Veterinary microbiology》2002,87(2):149-157
A fluorescence polarization assay (FPA) utilizing fluorescein-labelled MPB70 protein as the antigen was developed and evaluated for its ability to detect antibodies to Mycobacterium bovis in cattle sera. Three panels of sera were examined in this study. These included: (A) sera (n=28) obtained from cattle from which M. bovis was cultured; (B) sera (n=5666) from Canadian field cattle which were presumed to be free from M. bovis; (C) sera (n=10) from cattle infected with Mycobacterium paratuberculosis and known to contain antibodies to this organism. Receiver operating characteristic (ROC) curve analysis of the results of panels A and B yielded an area under the curve value of 0.975 (95% confidence interval=0.971-0.979), which indicated that this FPA is an accurate indicator of M. bovis infection. At the cut-off point recommended by the ROC curve analysis, the FPA sensitivity and specificity estimates were 92.9% (95% confidence interval=76.5-98.9%) and 98.3% (95% confidence interval=97.9-98.6%) respectively. The FPA results were compared to the results of the single intradermal (SID) test for the 28 infected cattle. Fifteen of these animals were scored positive with the SID test (sensitivity=53.6%). The FPA detected 15/15 (100%) of the SID test-positive animals and 11/13 (84.6%) of the SID test-negative animals. Two of the culture-positive cattle were not detected by either test. None of the sera that were obtained from the M. paratuberculosis-infected animals cross-reacted in this assay. 相似文献
49.
Jolley ME Nasir MS Surujballi OP Romanowska A Renteria TB De la Mora A Lim A Bolin SR Michel AL Kostovic M Corrigan EC 《Veterinary microbiology》2007,120(1-2):113-121
The performance of a fluorescence polarization assay (FPA) that detects antibodies to Mycobacterium bovis in bovine sera is described. The FPA reported here is a direct binding primary screening assay using a small polypeptide derived from the M. bovis MPB70 protein. A secondary inhibition assay confirms suspect or presumed positive samples. Specificity studies involved five different veterinary laboratories testing 4461 presumed negative bovine samples. FPA specificity was 99.9%. The FPA was used to identify herd status as either M. bovis infected or non-infected. Herd surveillance studies (nine herds) were performed in Mexico and South Africa. The FPA had a specificity of 100% (two negative herds), and correctly identified six of seven infected herds. Finally, sera from 105 slaughter animals that had gross lesions in lymph nodes similar to those seen with bovine tuberculosis were tested by the FPA. Thin sections from the associated formalin-fixed paraffin-embedded samples of lymph nodes were stained using hematoxylin and eosin (H&E) for morphologic examination and using the Ziehl-Neelsen (ZN) method for detection of acid-fast bacilli. Of the 105 animals, 78 were classified as TB suspect based on lesion morphology, 21 were positive by ZN, 9 were positive by FPA and 13 were positive by PCR for the tuberculosis group of Mycobacterium. Among the 21 ZN positives, 11 (52.4%) were PCR positive. Among the 9 FPA positives, 8 (88.9%) were PCR positive. For the 13 PCR positives, 8 (61.5%) were FPA positive and 11 (84.6%) were ZN positives. These results show that use of the FPA for detection of M. bovis infection of cattle has value for bovine disease surveillance programs. 相似文献
50.
Sunil Kumar Dinesh Kumar K. S. Sekhon Om Parkash Choudhary 《Communications in Soil Science and Plant Analysis》2018,49(4):499-514
A field experiment was conducted to study the influence of boron (B) application on yield and B uptake of cotton (Gossypium hirsutum L.) in B-deficient calcareous soil of south-west Punjab. The treatments comprise six levels of soil-applied B (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 mg B kg?1soil) and two levels of foliar-applied B (0.1% and 0.2% borax and granubor solution) along with the common control (no B application). The experiment was laid out in RBD factorial design with three replications. The seed cotton yield and its attributing characters (plant height, number of sympodial and monopodial branches, boll weight, and number of boll per plant) and root biomass increased significantly with increasing levels of boron up to 1.0 mg B kg?1 level over the control and then remained nonsignificant with further higher levels of soil-applied boron. Among foliar-applied boron levels, 0.1% borax solution was better than 0.2% borax solution. Soil-applied boron was at par with foliar-applied boron. The efficiency of borax and granubor was found to be equal in both sources of boron. The mean B content and its uptake by seed cotton and roots increased significantly up to 1.0 mg B kg?1 soil-applied B level and then recorded nonsignificant with further higher levels of boron. For the foliar method of B application, the mean B content and its uptake by seed cotton increased significantly over the control. The mean available B content in soils (0–15 cm) at 45, 75, 105, and 145 days after sowing increased significantly over the control for all soil-applied B levels, while it remained nonsignificant over the control for all growth stages of cotton in foliar method of B application. Further, it was positively correlated with root biomass (r = 0.91), boron uptake by root (r = 0.98), and sympodial branch per plant (r = 0.81). The interaction of B application levels and sources was not significant for all studied traits. Regardless of B sources, B application had a significant effect on yield, yield attributes, and B uptake up to 1.0 mg B kg?1 level for soil-applied B and 0.1% borax or granubor solution for foliar-applied B. 相似文献