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The system of rice intensification (SRI) has generated considerable debate globally, particularly with regard to its potential to raise rice yields. Proponents of SRI have reported that the average rice yield with SRI is double the current average yield and can be increased to the level of three to four times. Opponents say the reported high yields are due to measurement error and that usual information expected in support of these fantastic yields is missing. The number of SRI adopters has increased in India in recent years. We evaluate the impact of adoption of SRI practices on rice yields, the economics of paddy cultivation and labour inputs based on field research conducted in Purulia, West Bengal, India. Paddy yields with SRI were higher than those under conventional paddy cultivation by 32% and net returns were higher by 67%. Labour input was reduced by 8%. SRI adoption enabled farmers consistently to enhance paddy yields, increase returns and save labour; and enhance productivity with respect to the key inputs in terms of paddy output per unit of seed, fertilizer and labour-day. SRI promises to be a significant alternative for not only raising paddy yields, but also for managing paddy based farming in resource-starved regions.  相似文献   
2.
This study aims to evaluate the conjunctiva colour-based FAMACHA score (FS) coupled with a body condition score (BCS), haemogram and stressor hormone level estimation, in identifying post-mortem (PM)/coproscopically proven individuals wanting therapy for economically important gastrointestinal (GI) helminths, Haemonchus contortus, in the small ruminants. The incidence of haemonchosis was significantly (p < 0.05) higher (60.81%) in the ruminants with FS = 3. The H. contortus count in the animals with FS 2, 3 and 4 was 23.2 ± 0.37, 62 ± 2.5 and 74 ± 3.2 (p < 0.05) [positive correlation (r = 0.841 in goats; r = 0.828 in sheep, p < 0.05)], respectively, with corresponding 2.8 ± 0.15, 2 ± 0.3 and 2 ± 0.16 BCS (negative correlation, p > 0.05). The infected animals of FS 2, 3 and 4 measured 8.2 ± 0.0, 7.5 ± 0.23 and 6.7 ± 0.34 g/dl Hb (r = ?0.452, p = 0.01) in goats/9.3 ± 0.8, 8.6 ± 0.5 and 7.6 ± 0.3 g/dl Hb (r = ?0.511, p = 0.05) in sheep with 21.2, 19.8 ± 1.8 and 17.8 ± 0.2% PCV (r = ?0.369, p = 0.05) in goats/26.7 ± 1.2, 22.2 ± 0.2 and 20.9 ± 0.6% PCV (r = ?0.251, p = 0.03) in sheep, respectively. The FS 2, 3 and 4 infected goats/sheep measured 6.1 ± 0, 7.9 ± 1.0 and 9.5 ± 0.9 (p < 0.05)/5.8 ± 2.3, 6.9 ± 1.2 and 7.8 ± 0.2% (p < 0.05) mid-granulocyte [(r = 0.928 (goats)/0.834 (sheep), p < 0.05], while the cortisol level was 15.6, 23 ± 4.5 and 42 ± 2.3 (p = 0.23)/12.1 ± 0, 15.9 ± 1.2 and 24 ± 3.4 (p = 0.29) μg/dl, respectively. The infected ruminants recorded low (p < 0.05) level of Hb/PCV while high level of mid-granulocytes/cortisol. Specificity of FAMACHA test was maximized (100%) when FS = 4 was considered anaemic, but sensitivity was low (35.29% in goats; 25% in sheep). The false negatives was 5.9 (goat)/12.5 (sheep)% when FS ≥ 3 was considered anaemic. The small ruminants with FS ≥ 3, BCS ≤ 2.5, Hb ≤ 7.5 g/dl (goats)/8.6 g/dl (sheep), PCV ≤ 19.8% (goats)/22.2% (sheep) and mid-granulocyte ≥7.9% (goats)/6.9 ± 1.2% (sheep) can be subjected to target-selective treatment for haemonchosis in the field simultaneously maximizing the economic benefit to the farmers.  相似文献   
3.
Gujarat, a rapidly industrializing state in western India, is notorious for groundwater over-exploitation. A perverse link between energy subsidies and groundwater overdraft has left the state with a bankrupt electricity utility and depleted aquifers, especially since the late 1980s. Moreover, this perverse relationship has meant that groundwater irrigators have essentially held Gujarat's non-farm rural economy to ransom. Efforts to regulate groundwater overdraft since the early 1970s have been unsuccessful, as have attempts to charge a rational electricity tariff to groundwater irrigators. During 2003-2006, drawing upon a proposal outlined by researchers, the government launched the Jyotigram (lighted village) scheme, which invested US$ 290 million to separate agricultural electricity feeders from non-agricultural ones, and established a tight regimen for farm power rationing in the countryside. By 2006, Gujarat covered almost all of its 18,000 villages under the Jyotigram scheme of rationalized power supply. With this, two major changes have occurred: (a) villages receive 24 h three-phase power supply for domestic uses, in schools, hospitals, village industries, all subject to metered tariff; (b) tubewell owners receive 8 h/day of power of full voltage and on a pre-announced schedule. The Jyotigram scheme has radically improved the quality of village life, spurred non-farm economic enterprises, halved the power subsidy to agriculture, and reduced groundwater overdraft. It has also produced positive and negative impacts on medium and large farmers, while notably harming marginal farmers and the landless, who depend for their access to irrigation on water markets which have become much smaller, post-Jyotigram. In addition, the water prices charged by tubewell owners have increased by 30-50%. We propose that the Jyotigram scheme, with some refinements, can be implemented successfully in other regions of South Asia facing similar challenges of groundwater governance.  相似文献   
4.
Genetic Resources and Crop Evolution - Garcinia L. is a pantropically distributed genus with high species richness in South East Asia. It is a tropical evergreen plant with distinct morphological...  相似文献   
5.
Shrimp cell lines are yet to be reported and this restricts the prospects of investigating the associated viral pathogens, especially white spot syndrome virus (WSSV). In this context, development of primary cell cultures from lymphoid organs was standardized. Poly-l-lysine-coated culture vessels enhanced growth of lymphoid cells, while the application of vertebrate growth factors did not, except insulin-like growth factor-1 (IGF-1). Susceptibility of the lymphoid cells to WSSV was confirmed by immunofluoresence assay using monoclonal antibody against the 28 kDa envelope protein of WSSV. Expression of viral and immune-related genes in WSSV-infected lymphoid cultures could be demonstrated by RT-PCR. This emphasizes the utility of lymphoid primary cell culture as a platform for research in virus-cell interaction, virus morphogenesis, up and downregulation of shrimp immune-related genes, and also for the discovery of novel drugs to combat WSSV in shrimp culture.  相似文献   
6.
Tissues of higher plants contain novel natural substances that can be used to develop environmental safe methods for insect control. In this study, ethanol extract from flowers of Verbascum cheiranthifolium Boiss. (Scrophulariaceae) was examined for their effect on mortality and progeny production against adults of Rhyzopertha dominica (F.) on two commodities, wheat and barley. The botanical extract was applied at five dose rates, which 0.25, 0.5, 1.0, 2.0 and 3% (w/v). Adults of R. dominica were exposed to the treated wheat and peeled barley at 25 degrees C and 65% RH and mortality was assessed after 24 h, 48 h, 7 day, 14 day and 21 day of exposure. Then all adults were removed and the treated substrate remained at the same conditions for an additional 45 day after this interval, the commodities were checked for progeny production. In two commodities mortality increased with the increase of dose and exposure interval. Results indicated that on wheat, mortality was 100% after 14 days of exposure at the highest dose rate. Whereas, in the same conditions mortality of adults on barley was 63%. Thus plant extract was more effective against adults of R. dominica on wheat than application of barley. Interestingly in two diets, complete suppression (100%) of the progeny production was observed in the treated wheat and barley than in control even in the lowest dose rate.  相似文献   
7.
We have used the cyclopoid copepod Paracyclopina nana to understand responses to the temperature shift. To determine the changes of molecular mechanisms, which would lead to physiological changes in P. nana, we investigated mRNA expression involved in lipogenesis, the area of lipid droplets, the ratio of fatty acids, and life parameters (growth and fecundity) in response to temperature changes (15, 20, and 30 °C) with comparative control at 25 °C. Setting the temperature 25 °C as a standard point, there were increases in mRNA expression, the area of the lipid droplets, and fatty acid composition at temperatures below the standard (15 °C), while all the markers mentioned above significantly decreased at higher temperatures than the standard (25 °C). Through fecundity and growth rate experiments, daily nauplii production was reduced and growth retardation was observed at both 15 and 20 °C, but no noticeable differences in the two parameters were observed at 30 °C compared to the control (25 °C). This study provides a better understanding of the effects of temperature on lipogenesis in copepods.  相似文献   
8.
In California, USA, agricultural fumigant use regulations hinder the complete transition from methyl bromide (MB) to alternative fumigants. Alternative fumigants such as 1,3-dichloropropene (1,3-D) and chloropicrin (Pic) are being used on approximately half of California conventional strawberry production fields. Geographic use limits and buffer zones set by the California Department of Pesticide Regulation for 1,3-D + Pic restrict a more complete replacement of MB. Due to the regulatory constraints and public resistance to fumigant use, it is necessary to develop fumigant-free strawberry production systems. Trials were conducted during the 2007/2008 and 2008/2009 strawberry growing seasons at Salinas and Watsonville, California. Non-fumigant treatments including steam, mustard seed meal (MSM), Muscodor albus, and furfural, fertilizers including Mustard Products & Technologies fertilizer and stabilised urea, and fungicide treatments including AG3(NP), fludioxonil + mefenoxam (mfx), and mfx + thiophanate-methyl were evaluated for weed control and strawberry fruit yield, and compared to MB + Pic (MBPic) standard soil fumigation and an untreated control. Steam treatment applied pre-plant to achieve soil temperature of ≥70 °C for 20 min up to 25 cm soil depth consistently provided weed control similar to the MBPic standard soil fumigation. Use of oxyfluorfen herbicide prior to fungicide applications in 2008/2009 also controlled weeds similar to the MBPic standard soil fumigation. Strawberry yields in steam-treated plots with the exception of steam alone in 2007/2008 at Salinas, were comparable to MBPic. At Watsonville in 2008/2009, treatment effect on strawberry yields was insignificant. Yields in furfural and MSM treatments were comparable to MBPic only in some years or sites. With the exception of steam, none of the treatments can be considered viable replacement to MB.  相似文献   
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