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31.
In this experiment, weed management was studied in zero tillage (ZT) and conventional tillage (CT) wheat with and without crop residue and nitrogen (N). The treatment ZT with crop residue retention (R) and 75% of required N plus GreenSeeker? (GS)-aided N management (ZTRNGS) resulted in a reduction of density and dry weight of weeds compared to CT and ZT without residue. Sequential application of pendimethalin and sulfosulfuron (PMT-SSF) reduced the weed density and dry weight compared to the weedy check (WC). Importantly, the richness and diversity indices were high in ZTRNGS and in WC treatments. Greater wheat grain (5.11 t/ha) and biomass yield (13.31 t/ha) were observed in ZTRNGS than CT without residue and blanket split application of N (CTN). The treatment ZTRNGS recorded 14.1% and 16.9% higher gross and net returns, respectively, over CTN. This study demonstrates that surface retention of crop residue in ZT is more useful than residue incorporation under CT for effective weed control, improving crop yield and profitability.  相似文献   
32.
The Western Himalayan region of India possesses rich genetic diversity of rice (Oryza sativa L.). Rice landraces having withstood the rigors of biotic and abiotic stresses, suit to the local conditions of farms and reflect socio-cultural preferences can still be found in crop fields located distantly in rural and tribal areas. This region is known for growing World fame basmati in the foot hills and many varieties of red rices grown at higher elevations, known for cold tolerance and medicinal properties. Genetic resources of rice were collected for about 8 years (1999–2006) and 1069 germplasm accessions including 154 named landraces were collected. Prominent landraces such as Begumi, Ramjwain, Thapachini, Naurang, Hansraj, Tilakchandan, Lalsati, Jhini, Mushakbudji, Jattoo, Barpasso, Qadirbeigh, Safedbrez, Shahie known for their special quality attributes were collected. The change in land use, cropping patterns and aggressive introduction of modern varieties in the region has resulted in the loss of a large number of landraces especially from irrigated lands. The present paper looks at the status of rice genetic resources, genetic variability, genetic erosion and future strategies to conserve rice germplasm on farm and to maximize its use in rice breeding.  相似文献   
33.
This research was conducted to explore genetic material that can yield better under salt stress conditions. The experiment was laid out using 27 upland cotton genotypes in a RCBD 2 factorial arrangement with two replications. Saline water (NaCl at 20 dS/m) was applied after satisfactory emergence was achieved. The crop was raised to maturity and data relating to yield, fiber quality and ionic traits were recorded. Analysis of variance showed significant variations in the germplasm. Plant height, bolls per plant, boll weight, GOT%, staple length, staple strength, K+ and K+/Na+ ratio under salinity stress showed a highly significant correlation with seed-cotton yield. The highest direct effect on seedcotton yield per plant was exhibited by bolls per plant and boll weight. The results from the correlation and path coefficient analyses revealed that although the K+/Na+ ratio had a strong positively significant association with seedcotton yield, its direct effect on the seed-cotton yield was negative and thus selection on the basis of K+/Na+ may not be fruitful. Hence, only indirect selection through bolls per plant and boll weight may be effective in increasing the seedcotton yield per plant under salinity stress.  相似文献   
34.
The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods.  相似文献   
35.
Potato processing in India has shown a tremendous growth in the recent past, creating a proportionate increase in demand for processing quality potatoes. Reliable annual demand estimates of processing quality potato tubers in India were not available; hence, the current study was undertaken to provide such estimates. The study was based on a survey of 442 households in the state Maharashtra in India, which was regarded to be representative for India in the consumption of processed potato products. The annual expenditure on potato products during 2006–2007 in Maharashtra was estimated to be INR 5,254 million (€ 93.82 million), which was equivalent to 28,148 Mg of physical processed potato products and 83,333 Mg of processing quality potato tubers (0.38% of national potato production during 2006–2007, i.e. 22.09 million Mg). When the estimates were generalised to a national level, the requirement of processing-quality potato tubers in 2006–2007 was equal to 4.04% of national potato production. The forecasted annual demand of potato products in Maharashtra during 2011–2012 was 75,375 Mg and the corresponding demand of processing quality potato tubers was 230,760 Mg (0.75% of the estimated national potato production during 2011–2012, i.e. 30.89 million Mg). When generalised at national level, the demand of processing quality potato tubers during 2011–2012 was found to be 8% of the estimated national potato production.  相似文献   
36.
An exploratory survey was carried out to assess economics and employment generation of the trade of bamboo and bamboo-based secondary products in the eastern Bangladesh, to obtain reliable information about their status, socio-economic significance, production and marketing. The study was undertaken over 30 bamboo-based enterprises in a suburban market of eastern Bangladesh, to investigate regional product details, economic profitability and employment opportunities. The sample entrepreneurs, corresponding to about 25% of the bamboo enterprise population were interviewed using a semi-structured questionnaire. About 202 full and part-time workers were employed in the factories, under categories of artisan (who manufactured secondary products). The average number of worker’s in the large, medium and small factories were 9 (artisan 40%), 6.45 (artisan 35%) and 5 (artisan 25%) respectively. The study revealed that there was always a satisfied demand of skilled artisans. Most of the workers were relatively newly employed (not more than 5 years). The daily wage rate varied between 70 and 130 Tk. ($US 1 equals approximately 70 Bangladeshi Taka (Tk.), as at December 2008). Bambusa balcooa was the most utilized species (39.96%) in terms of monetary value. The price of a single B. balcooa culm in the local market was Tk. 160–210. Nine sizes of articles under seven bamboo categories were identified, these being bera (36″ × 120″ and 72″ × 96″), bookshelf (36″ × 24″), chaluni (12″ × 12″), chatai (48″ × 60″ and 36″ × 48″), jhuri, rickshaw hood and tukri. Net average profit per article was the highest for rickshaw hoods (Tk. 400 at the retailer stage). The total expected annual income for an enterprises from all articles types sold was estimated to be Tk. 85,800. Three distinct marketing channels were identified for selling bamboo and value-added secondary products. The study also generated policy implications for effective management of bamboo-based enterprises.  相似文献   
37.
This study was carried out to investigate the prevalence of bovine brucellosis and infectious bovine rhinotracheitis (IBR) in organized dairy farms with history of abortion in India. ELISA and Rose Bengal Plate Test (RBPT) were used to detect the seropositive animals and the test results indicated that 22.18% and 13.78% animals were declared as sero-positive by ELISA and RBPT, respectively. Milk Ring Test (MRT) was carried out only in one farm and 12.82% of the tested animals were turned positive. Culture examination analysis of milk samples, two animals revealed the presence of organisms indistinguishable from Brucella spp. The organism was confirmed as brucella by morphological characteristics and biochemical tests. An overall sero-prevalence of antibodies against IBR was found to be 60.84%. None of the genital and nasal swab samples was found to be positive for presence of bovine herpesvirus -1 (BHV-1) on repeated passage in Madin-Darby Bovine Kidney (MDBK) cell lines. Brucella and IBR considered as the causal agent for abortions in these farms. The present study indicates the urgent need and the necessity for control of these infectious diseases which cause heavy economic losses to the organized farms.  相似文献   
38.
39.
The chemical composition of essential oils isolated from aerial parts of native populations of Origanum vulgare L. from northwestern Himalaya was investigated by enantioselective gas chromatography (enantio-GC), capillary-gas chromatography (capillary-GC) and GC–MS. Seventy compounds, which accounted for 84.9–97% of the oil composition, have been identified. The oils were allotted to two main groups; the first group had a high percentage of components belonging to the thymol/carvacrol biosynthetic pathway and the second was characterized by a different sesquiterpene composition and a high linalool and bornyl acetate percentage. Essential oils of O. vulgare populations from Rilkot and Dhanachuli areas in northwestern Himalaya were characterized by high monoterpenoids proportions as compared to Nainital and Bhowali populations, which were dominated by sesquiterpenoids. High proportions of thymol (29.2–82%) were found only in two populations. Composition of the samples collected from Dhanachuli area differed from Nainital and Bhowali collections by a unique presence of carvacrol. Notably, there were significant differences in the concentration of rest of the terpenes in all the collections. On enantio-GC, enantiomeric excess for (3R) (−)- and (3S) (+)-linalool, (S) (+)- and (R) (−)-terpinen-4-ol, (S) (−)- and (R) (+)-α-terpineol, (1S) (−)-bornyl acetate and (1S) (−)-borneol were established in populations from Bhowali and Dhanachuli area. Moreover, linalool type oregano may be useful in promoting wider commercial utilization of the biodiversity of this species.  相似文献   
40.
Soybean plants were subjected, during their growing seasons, to well-watered and water-stressed conditions, and three levels of ozone concentration (zero, low and high) in open top chambers (OTCs). At the end of the soybean growing season accumulated AOT40 values were zero, 3400 and 9000 ppb h for the filtered (control), low and high levels of ozone concentration, respectively.

In well-watered conditions, an increase in ozone concentration led to a reduction in leaf area, dry matter and reproductive organs. Whereas, an increase in ozone had no effect on plants in water-stressed conditions. At a high level of ozone concentration, there was a 47% reduction in yield and a 25% reduction in WUE in comparison with the control treatment. The reduction in yield was due to a lower number of pods per plant and 1000-grain weight. Despite changes in the grain yield, the yield quality was not altered by ozone.

During the 3-year study, AOT40 was significantly correlated with the leaf area and the final above-ground dry matter. The latter was less sensitive to ozone than leaf area. These results were reliable and would be useful in soybean yield-prediction models.

Finally, the conclusion highlights the reliability of the approach adopted, which was to make observations on various time scales (hourly, daily and entire crop cycle).  相似文献   

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