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31.
The opium latex of 1470 individual plant samples of 98 germplasm lines were screened for five major economic alkaloids. The alkaloids profile showed that morphine content ranged from 9.20–20.86% with an average of 15.00 ± 0.267. Codeine ranged from 1.69–6.48% with arithmetic mean of 3.35 ± 0.091, thebaine from 0.52–7.95% with an average of 2.27 ± 0.116. Narcotine ranged from 8.79–17.97% with an average 8.79 ± 0.266 and papaverine content ranged from 0.00–6.07% with an average 1.18 ± 0.167 in over all the germplasm lines. The content of different alkaloids categorized into class interval which exhibited that maximum number of plants and accessions for morphine content fall in group of 10–15% followed by 15–20%, for codeine content in group of 2–4% followed by 4–6%, for thebaine content in 1–2% followed by 2–4%, for narcotine in 5–10% followed by 10–15% and for papaverine content 0–2%. 24 germplasm lines had morphine content above 16.0%. Similarly, 37 germplasm lines for codeine and 13 for thebaine showed consistently high content, i.e., above 3%. 33 germplasm lines had narcotine content above 9% and 20 lines exhibited papaverine content above 2%. Line BR 316 was found unique having thebaine content 6.27–9.33%. The probable reasons of increase or decrease of different alkaloids based on their biosynthetic pathway has been discussed in detail.  相似文献   
32.
The effect of different levels of K application on the transformation of native as well as applied Zn fractions in a rice-growing soil was studied under two moisture regimes viz. waterlogged and alternate waterlogged and saturation. Application of K caused an increase in the water-soluble plus exchangeable, organically complexed and carbonates, and other acid-soluble mineral fractions of native soil Zn. Application of K also caused an increase in the transformation of applied Zn into all the above three fractions of the element in soil. The above effects of K were more pronounced in soil under waterlogged than under alternate waterlogged and non-waterlogged moisture regimes. The results of a greenhouse experiment showed that K application caused an increase in Zn uptake and per cent utilization of both native and added Zn by rice. This was attributed to the increase in the water-soluble plus exchangeable and organically complexed forms of Zn in soil due to K application.  相似文献   
33.
Mulberry, Morus spp. has a wide range of use, the chief among them is to feed the silk producing caterpillar Bombyx mori L. (Bombycidae; Bombycoidea). As a homeland of mulberry, India has a number of indigenous mulberry species, of which a few are widely cultivated. In the present investigation genetic distance among such eleven mulberry cultivars originated from six different states of India covering a wide geographic area extending from 15° N to 32° N latitude and 72°E to 89°E longitude was studied using inter-simple sequence repeat primers. Out of the 20primers tested, 13 primers, viz, nine di-nucleotide, three tri-nucleotide and one penta-nucleotide repeats, gave clear and reproducible band profiles. While the (AT)n rich primers could not amplify the DNA, the (GA)n, (AC)n and (AG)n rich primers gave excellent amplification profiles. The genetic distance among the cultivars varied from a minimum of 0.053, between Punjab local and Bombay local, to a maximum of 0.431, between Almora local andSujanpur-5. Clustering of the cultivars according to nearest neighbor method created three groups. The north-Indian cultivars made a separate and distinct group while the cultivars originated from eastern and southern India occupied a distinct position. Almora local was found quite different from others. The first two canonical functions identified through discriminant function analysis accounted for 91.2% of the total variability. Distribution of cultivars belonging to six different zones on canonical matrix realized from Discriminant Function Analysis (DFA) revealed wider variability for West Bengal, Karnataka and Punjab which reaches the group centroids of Uttar Pradesh and Himachal Pradesh. This attests to the past contribution of West Bengal in east and Karnataka in south towards development of mulberry cultivars indifferent parts of India. Step-wise linear regression analysis, further, identified two markers (825.1400 and835.750) associated with leaf yield, which also satisfied the Beta estimation, thereby testifying strong association of these two markers with leaf yield. This finding along with the classification of the eleven cultivars bear strong relevance to mulberry breeding for different agro climatic areas. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
34.
Sesamia inferens (Walker) causes 25.7–78.9% losses in maize production in South and South‐East Asia. The genetic basis of host plant resistance is the prerequisite for resistance breeding. Twenty‐four populations derived from S. inferens resistant × susceptible inbreds were used to study the genetic regulation of resistance to S. inferens in maize, to determine the importance of genetic effects through generation mean analysis (GMA) and to understand correlation between resistance and yield. Resistant and susceptible inbreds differed significantly in leaf and stem injury ratings (LSIR), a measure of host plant resistance. Mean LSIR range among resistant and susceptible parents was 2.15–2.55 and 7.83–8.22, respectively. The broad‐sense heritability ranged from 0.40 to 0.71, and the mean number of effective factors ranged from 1.9 to 2.6. The resistance against S. inferens was largely governed by additive × additive (i), followed by dominance (d) and additive (a) gene effects. Significant negative correlation (?0.27 to ?0.96) was observed between LSIR and yield. The findings suggest reciprocal recurrent selection for development of new inbreds with resistance followed by their involvement in hybrid development to exploit additive and non‐additive gene effects/variance.  相似文献   
35.
ABSTRACT This paper explores possible ways in which growth in Internet retailing (e‐retailing) may affect the spatial distribution of economic activities. After a brief overview of e‐retailing, a categorization of possible spatial impacts is introduced. These include impacts on the retail industry, such as substitution of e‐retail for brick‐and‐mortar retail, impacts on transportation, such as substitution of freight transportation for personal transportation in goods delivery, and pervasive impacts that affect the whole economy. The latter category includes uniform delivered pricing, spatial leveling of accessibility, and marketing strategies that target individuals rather than regions. The question of whether e‐retailing and brick‐and‐mortar retailing are truly substitutes is taken up in the next section, along with potential implications of multi‐channel retailing. The final section of the paper defines some critical research directions.  相似文献   
36.
1. Single strand conformation polymorphism analysis and DNA sequencing was performed in White Leghorn hens to explore the polymorphisms present in the promoter of the prolactin gene. The effects of different genotypes on egg production and quality traits were determined, and expression of the prolactin gene in different genotypes was quantified by real time-PCR.

2. Five genotypes and four alleles at each of two Fragments of the promoter were found, of which the FG genotype in Fragment 1 and the PQ genotype in Fragment 2 were the most predominant genotypes.

3. The genotypes of Fragment 1 had significant effects (P?

4. Prolactin expression in the genotypes of Fragment 1 differed significantly and GH genotyped birds had the highest level of expression. The genotypes of Fragment 2 did not show any significant differences of expression.

5. It was concluded that the prolactin gene promoter was highly polymorphic, and had significant effects on egg quality traits in White Leghorn hens.  相似文献   

37.
Filarial parasites, Litomosoides carinii and Setaria cervi, showed great susceptibility to the oxidants generated in vitro by the xanthine/xanthine-oxidase system. In order to counteract such injurious effects, both the filariids possessed an active antioxidant enzymes system. Superoxide dismutase, catalase and glutathione peroxidase were detected in appreciable amounts but glutathione reductase and glucose-6-phosphate dehydrogenase in very low quantities. The former three enzymes were also found to be released by the parasites into the ambient medium. The released enzymes may be responsible for scavenging the host-generated oxidants present in the immediate surroundings of the parasites and thereby enabling them to live comfortably in the host. This Institute-based antifilarial agent namely Compound 82/437 which is 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolylketone, markedly inhibited catalase and glutathione peroxidase of both L. carinii and S. cervi. The compound, therefore, appears to render the filariids prone to H2O2 toxicity leading to penultimate damage.  相似文献   
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Experiments were conducted to analyse the effect of 3-year-old grass plots, under a cut-and-carry system, on the yields of maize and groundnut crops, and at the same time to compare the relative importance of the water-stable aggregates and the nitrogen status of the soil. The N reserves, organic carbon and water-stable aggregate contents of soils were higher under grass plots than in the ploughed-up-fallow plots. Maize yields showed a close correlation with total soil N, mineralized N after incubation for 20 days, and water-stable aggregate contents; groundnut yields showed close correlation only with water-stable aggregates. The effects of the variations in soil N and in the water-stable aggregate content of the soil on the yields of maize and groundnuts were examined by multiple regression analysis of data from a large number of plots.  相似文献   
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