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61.
Qualitative and quantitative analysis of polar lipids in sun flower (Helianthus annuus L.) seed is reported in the present study. Ten classes of polar lipids i.e. phosphatidic acid, phosphatidyl inositol, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, diphosphatidyl glycerol, digalactosyl diglyceride, monogalactosyl diglyceride, esterified sterol glycoside and free fatty acids have been identified. Phosphatidyl choline and phosphatidyl inositol formed the major phosphatide fractions. Only four fatty acids i.e. palmitic, stearic, oleic and linoleic acids were present in measurable amounts in the total polar lipids. There was a great variation in the fatty acid composition in different classes of polar lipids. Arachidic acid was present in all the individual phosphatide fractions. Phosphatidyl glycerol was highly unsaturated followed by esterified sterolglycoside, phosphatidic acid, phosphatidyl ethanolamine + phosphatidyl glycerol, diphosphatidyl glycerol and monogalactosyl diglyceride.  相似文献   
62.
Selection For Flag Leaf Stomatal Frequency In Bread Wheat   总被引:1,自引:0,他引:1  
Two Cultivars Of Bread Wheat (Triticum Aestivum L.) Showing Significant Differences In Stomatal Frequency On The Adaxial Surface Of The Flag Leaf Blade, Were Hybridized. Transgressive Segregation For Stomatal Frequency Was Observed In The F2 Generation and Selections Were Made For High and Low Stomatal Frequency. In The F9 Generation Two Selections Had Significantly Higher Frequencies Than The Higher Parent. Heritability For Stomatal Frequency Based On Parent-Progeny Regression Were 42 % (F3—F4) and 81 % (F4—F5). Stomatal Frequency Was Negatively Correlated With The Flag Leaf Blade Area, Mesophyll Cell Size and Grain Size, However, Exceptions Were Observed.  相似文献   
63.
R. Mitra  C. R. Bhatia 《Euphytica》1982,31(2):429-437
Summary The bioenergetic cost (glucose requirement to provide carbon skeletons and energy production) for the synthesis of 35 chemicals implicated as phytoalexins in combating fungal and bacterial infections as well as the allelochemicals responsible for non-preference or antibiosis in insect-plant interactions were calculated. Heat of combustion values which represent the intrinsic energy content of the molecule for these chemicals, were also computed. The results indicate that the energetic cost of the chemicals responsible for genetic resistance is not exceptionally higher. In fact, they are comparable to those of many fatty acids found in plants. Though the concentration of the chemicals responsible for resistance is low in plant tissues, the total amount per hectare is quite high and consequently the plant resources that go to produce these are high.  相似文献   
64.
Summary In a field experiment, plant (excluding roots) and grain nitrogen at harvest were estimated in 15 durum wheat cultivars varying in their grain protein concentration. They showed significant variation in grain yield, grain protein concentration, biological yield, total plant nitrogen at harvest and residual nitrogen in straw. Harvest index and nitrogen harvest index were calculated from this primary data. Nitrogen harvest index varied from 57 to 83%. Plant nitrogen showed significant positive correlation with biological yield, grain yield and grain protein yield, but the correlations with grain protein concentration, harvest index and nitrogen harvest index were not significant. Nitrogen harvest index was positively correlated with harvest index indicating that the distribution of N between straw and grain to a large extent, but not entirely, depends upon the partitioning of dry matter between the two. Grain protein concentration was neither correlated significantly to plant nitrogen nor to nitrogen harvest index.  相似文献   
65.
Adult Spirometra sp. were found in an experimental cat. This is the first report from northern India. It is suggested that this infection may have resulted from the feeding of raw fish offal.  相似文献   
66.
The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), acid phosphatase (ACP), lactate dehydrogenase (LDH) and isocitric dehydrogenase (ICD) in the serum of 60 healthy dromedary camels of either sex and different ages (one to 25 years) were determined. The results were analysed with respect to time of year (December-January and May-June), sex and age groups (below four years; four to 10 years; and over 10 years). The overall mean activities of AST, ALT, ALP, ACP, LDH and ICD were 36.1 +/- 0.35, 4.65 +/- 0.35, 27.21 +/- 0.43, 7.18 +/- 0.21, 479.0 +/- 7.33 and 7.74 +/- 0.17 iu litre-1, respectively. Activities of AST, ALT, ALP and ACP were significantly higher during extremely hot conditions (May-June) than in extreme cold (December-January) while the activity of LDH was higher in extremely cold conditions. Analysis of data based on sex revealed that AST, ALT and ALP activities in the serum of male animals were significantly higher than in female animals. The activities of all the enzymes were highest in animals under four years and then gradually decreased with age being lowest in the animals over 10 years.  相似文献   
67.
68.
An internal physiological ripening disorder, “spongy tissue”, affects about 30% of ‘Alphonso’ mangoes, the most popular Indian cultivar. Fruits show no external symptoms at harvest or on ripening but cutting reveals internal damage to the mesocarp which adversely affects fruit quality. Both fully grown green, unripe mangoes and ripe fruits show spongy tissue. A non-destructive x-ray inspection method has been developed to detect affected mangoes. X-ray photographs and x-ray images of fruits having spongy tissue show dark grey patches corresponding to internal cavities in contrast to light grey areas of healthy flesh. The method could be used for quality control for on-line detection and separation of mangoes having spongy tissue prior to packaging, by monitoring x-ray screen images.  相似文献   
69.

Soybean is a temperate photosensitive crop but has adapted to sub-tropical and tropical countries of lower latitudes also. Photoperiodic and maturity genes confer latitudinal adaptation in this crop. Genotyping of accessions of higher latitudes have shown the role of photoinsensitivity, conferred by recessive photoperiodic alleles (e1/e2/e3/e4), in adaptation of the crop to high latitudes but information is not available for lower latitudinal countries like India. We genotyped and calculated the photosensitivity of 101 cultivated Indian soybean varieties and found that majority of the varieties (86) were photosensitive and had the dominant alleles at these loci. Four genotypic classes (e1-as/E2/E3/E4, E1/e2/e3/E4, E1/e2/E3/E4 and E1/E2/e3/E4) were observed for varieties with recessive alleles. Photoinsensitive alleles at E1 and E2 loci significantly reduced the days to flower, maturity and photosensitivity percentage. Adaptive role of photoperiodic alleles was inferred from breeder seed requirement of these varieties for 35 years. Although the photosensitive class contributed 81% to the total seed requirement the weighted mean contribution of this class (380 Q/year) was far less than that of photoinsensitive class (648 Q/year). Photoinsensitivity is essential for perpetuation of crop in higher latitudes. Present report highlights the novel role of photoinsensitive alleles in adaptation of soybean to rainfed, short growing and sub-tropical conditions of lower latitudes by conferring earliness.

  相似文献   
70.
Muscle samples from 890 slaughtered pigs were examined for the presence of sarcocysts. A high prevalence rate of 67.98% was observed. Two types of microsarcocysts were recorded. The sarcocyst wall of one type had redial striations and the other possessed hair-like villar protrusions. The species were identified as Sarcocystis miescheriana and Sarcocystis suihominis; there was a slightly higher incidence of the latter species (47.11%) than of the former (43.14%). S. suihominis has been identified for the first time from pigs in India.  相似文献   
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