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211.
Aluminum (Al) toxicity is an important factor in limiting crop production. The present study examined the Al alleviation effects on the growth of hybrid (breeding) and clonal (tissue culture) of D × P oil palm seedlings. The experiment was performed using calcium carbonate (CaCO3), and ground magnesium limestone (GML) and magnesium carbonate (MgCO3) as soil-amendments at different rates in Colombia and Malaysia, respectively. The effects of the treatments were evaluated monthly on vegetative variables and visual symptoms. Chlorophyll concentrations were recorded in Malaysia at the fifth month growing stage. The different amendments improved the soil fertility and it was reflected on better performance of shoot and root growth. The chlorophyll content in the frond number 3 for both materials enhanced significantly when Al saturation was low (0–30%). The results from the experiment revealed the importance of neutralization of Al in reducing its toxicity in oil palm.  相似文献   
212.
In India, insurance market especially in agricultural sector is usually underdeveloped. The idea of livestock insurance emerged in India before three decades, yet, it has not operated in a significant way till date. It is well noted that livestock insurance scheme is the relevant strategy in managing different risks related to livestock farming but very little attention has been paid to address the livestock insurance needs of the dairy farmers. This study, therefore, addresses the basic question that how many people and to what extent they are willing to pay for livestock insurance and determine the main factors which influence insurance participation of dairy farmers. The data was collected from Gorakhpur district of Uttar Pradesh in India with a sample survey of 120 cattle and buffalo farmers. For eliciting willingness to pay, a contingent valuation scenario was presented to dairy animal owners in the group of five to six. A logit discrete binary regression model was used to know the factors influencing adoption of livestock insurance. The results suggest that most of the farmers were willing to participate in cattle and buffalo insurance. The amount of premium varies across different breeds of dairy animals. The low level of education of many dairy farmers have negatively influenced the decision to purchase livestock insurance. Farmers having more experience in rearing dairy animals are more likely to be willing to pay for cattle and buffalo insurance.  相似文献   
213.
Examined was the effect of post mortem refrigerated storage on microbial spoilage, lipid‐protein oxidation and physicochemical traits of goat meat. Seven Boer bucks were slaughtered, eviscerated and aged for 24 h. The Longissimus lumborum (LL) and Semitendinosus (ST) muscles were excised and subjected to 13 days post mortem refrigerated storage. The pH, lipid and protein oxidation, tenderness, color and drip loss were determined in LL while microbiological analysis was performed on ST. Bacterial counts generally increased with increasing aging time and the limit for fresh meat was reached at day 14 post mortem. Significant differences were observed in malondialdehyde (MDA) content at day 7 of storage. The thiol concentration significantly reduced as aging time increased. The band intensities of myosin heavy chain (MHC) and troponin‐T significantly decreased as storage progressed, while actin remained relatively stable. After 14 days of aging, tenderness showed significant improvement while muscle pH and drip loss reduced with increase in storage time. Samples aged for 14 days had higher lightness (P < 0.05) and lower (P < 0.05) yellowness and redness. Post mortem refrigerated storage influenced oxidative and microbial stability and physico‐chemical properties of goat meat.  相似文献   
214.
This paper reports on a study of accretion rate and sedimentological variability in a estuarine mangrove swamp. One hundred and sixteen stations were monitored for 2 years. In addition, surface sediment samples were collected at 52 stations during the months of May, June and July (1994) to represent the nonmonsoon sediments and November, December (1994) and January (1995) to represent the monsoon sediments. Results show that the accretion rate for the first year was 1.46±0.13cm/yr and 0.66±0.04cm/yr for the second year thus making the average accretion for the 2 years period to be 1.06cm/yr. The average accretion rate for the monsoon season (0.26 ± 0.04cm/month) was found to be significantly higher than the nonmonsoon season (0.12 ± 0.03cm/month). Nevertheless, the same is not true for the surface sediment characteristics. The sedimentological characteristics between the monsoon and the nonmonsoon sediments were not significantly different.  相似文献   
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216.
Fragrance in rice is an appealing attribute to consumers. The increasing demand for fragrant rice highlights the need to develop fragrant rice variety that suit the preference of local consumers in addition to reduce fragrant rice imports. Marker-assisted backcrossing (MABC) was employed to develop advanced fragrant rice lines from the cross between MR269 and Basmati 370. MR269 is a Malaysian high-yielding rice variety but non-fragrant and was used as recurrent parent whereas Basmati 370 is a well-known fragrant traditional rice variety and was used as donor parent for the fragrance gene. Two generations of backcrosses and a generation of selfing were conducted to introgress the fragrance gene and restore the recurrent parent genome in the backcross progenies. As a result, 14 advanced fragrant rice lines were developed. These advanced fragrant rice lines carried homozygous alleles for the fragrance gene, similar to Basmati 370. The average recovery of recurrent parent genome was 88.4%. Besides being fragrant, the advanced fragrant rice lines also had most of the morphological and agronomical traits similar to MR269. Grain quality of the advanced fragrant rice lines in terms of gelatinization temperature, amylose content and gel consistency are also similar to both parents. Besides, the advanced fragrant rice lines had 2-acetyl-1-pyrroline content similar to Basmati 370. MABC approach applied in this study has successfully introgressed the fragrance gene and accelerated the recovery of recurrent parent genome in advanced fragrant rice lines, therefore these lines can be delivered to the farmers and consumers for use in due time.  相似文献   
217.
To conquer disease problem in shrimp industries, probiotic biocontrol is a well-known remedy now. The antagonistic ability of separated isolates from different parts of juvenile P. monodon was screened against shrimp Vibrio pathogens, V. parahaemolyticus and V. alginolyticus. The most antagonistic effect was observed for an isolate that primarily identified as Shewanella algae using conventional method followed by Biolog GN and GP microplates. Since adaptability to the host optimum cultural condition of the target organism is of the great importance, response surface methodology, with central composite design, was applied to assess log cell count response of S. algae in different incubation conditions. Therefore, four independent variables were assumed as: temperature (10–50°C), pH (6–10), NaCl concentration (0–50‰) and time (12–60 h). The coefficients of multiple determinations (R 2) for the responses log cell count of S. algae being 0.827. Temperature was the merely significant independent variable that affected the log cell count of the candidate probiotic. The candidate probiotic was revealed a reasonable growth response in quite wide range of temperature, pH and NaCl concentration in which the maximum levels were in same range of optimum shrimp culture.  相似文献   
218.
219.
Stocking of all‐male fingerling produced by direct administration of male hormone 17‐α‐methyltestosterone is the most preferred method for present‐day aquaculture of the Nile tilapia Oreochromis niloticus. However, due to the growing concern of negative impact of steroid hormone in food fish, production of ‘genetically male’ tilapia, which depends on the concrete and thorough understanding of sex determination, has long been a scientific curiosity. The objective of the present study was to identify reliable sex‐linked markers and to evaluate the applicability of those markers in terms of monosex production approach. ‘XY’ neofemales were produced by using synthetic oestrogen and identified through selective breeding and progeny testing. Three females with progeny not deviating from 3:1 sex ratio (male:female) were designated as ‘XY’ neofemales and were used subsequently to produce putative YY progeny. Among the fifteen microsatellite markers tested, marker ARO172 was most informative in differentiating male and female genotypes. Twenty‐seven F2 fish from three families were identified as putative YY males based on marker genotyping, and four of them were crossed to produce F3 to validate marker association by progeny testing. The YY males produced 86%–100% male progeny indicating ARO172 a unique sex‐linked marker applicable in marker‐assisted selection.  相似文献   
220.
Hybrid grouper juveniles (body weight, 6.1 ± 0.7 g) (brown‐marbled grouper, Epinephelus fuscoguttatus × giant grouper, E. lanceolatus) were fed with six isoproteic (50% crude protein) and isolipidic (12% crude lipid) feeds containing different levels of soy protein concentrate (SPC) in replacement of fish meal (SPC at 20%, 30%, 40%, 50% and 60% protein) and control feed (SPC0) for 6 weeks. Hybrid grouper juveniles were cultured in 100‐L fibreglass tank equipped with flow‐through water system and fed twice a day to apparent satiation level. The highest and lowest growth was recorded in fish fed SPC20 and SPC60 respectively. However, growth of SPC20 was not significantly higher than those fed SPC0, SPC30, SPC40 and SPC50 (p > .05). A decreasing growth trend was observed with the increasing level of SPC from feed SPC40 to SPC60. A noticeable better feed utilization was also observed in fish fed SPC0, SPC20, SPC30, SPC40 and SPC50 compared to fish fed SPC60 (p < .05). The fish condition factor, hepatosomatic index, viscerosomatic index and whole body proximate content of the fish were not affected by the graded levels of SPC. However, the body lipid content was significantly lower in fish fed SPC40 to SPC60 (p < .05). The apparent digestibility coefficient (ADC) of protein and lipid was significantly higher in fish fed SPC0 and SPC20 compared to other dietary treatments (p < .05). Based on the regression analysis on specific growth rate, the study suggests that the hybrid grouper grow best at 21.4% and can utilize up to 50% inclusion level of SPC in protein without significantly affect their growth and its body condition.  相似文献   
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