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81.
Introgression of unadapted genes from the wild Cicer species could contribute to the widening of genetic base of important traits such as yield, yield attributes and resistance to major biotic and abiotic stresses. An attempt was made successfully to intercross two wild annual Cicer species with three cultivated chickpea cultivars. Four interspecific cross‐combinations were made, and their true hybridity was ascertained through morphological and molecular markers. These cross‐combinations were also studied for some important quantitative traits under real field conditions. The range, mean and coefficient of variation of agro‐morphological traits were assessed in the parental lines, their F1 and F2 generations to determine the extent of variability generated in cultivated chickpea varieties. A high level of heterosis was recorded for number of pods/plant and seed yield/plant in F1 generation. Three cross‐combinations of ‘Pusa 1103’ × ILWC 46, ‘Pusa 256’ × ILWC 46 and ‘Pusa 256’ × ILWC 239 exhibited substantially higher variability for important yield‐related traits. The present research findings indicate that these wild annual Cicer species can be easily exploited to broaden the genetic base of cultivated gene pool for improving seed yield as well as adaptation.  相似文献   
82.
Long-term effects of intensive cultivation and imbalanced fertilization were studied on nutrient concentration of soil and in wheat grown on loamy sand alluvial soils belonging to Lukhi soil series located in semiarid-subtropical region of North-Western India. The same 86 farmers' fields were sampled during 2009 and 2010 which had earlier been studied during 1983 and 1984. Electrical conductivity of soil decreased, pH did not change, and organic carbon improved. In soil, K extractable in 1N NH4OAc and boiling 1N HNO3 depleted to a deficient levels in 2009 from medium levels of 1983. Similarly, DTPA extractable Cu depleted to deficient level from earlier sufficient level in 2009 from medium K and sufficient Cu levels in 1983. Consequently, K and Cu in the top two leaves of wheat decreased to a deficient level in 2010 from a sufficient level in 1984. Sulfur in soils and leaves decreased significantly. Olsen P and DTPA-extractable Zn increased, increasing their contents in leaves. DTPA-extractable manganese (Mn) and iron (Fe) improved.  相似文献   
83.
Plants resistant to the fungal pathogen Leptosphaeria maculans were generated by an interspecific cross between the highly susceptible Brassica napus (canola) and the highly resistant Brassica carinata. Changes in the leaf protein profiles of these lines were investigated in order to understand the biochemical basis for the observed resistance. Two-dimensional electrophoresis followed by tandem mass spectrometry led to the identification of proteins unique to the susceptible (5 proteins) and resistant genotypes (7 proteins) as well those that were differentially expressed in the resistant genotype 48 h after challenge with the pathogen (28 proteins). Proteins identified as being unique in the resistant plant material included superoxide dismutase, nitrate reductase, and carbonic anhydrase. Photosynthetic enzymes (fructose bisphosphate aldolase, triose phosphate isomerase, sedoheptulose bisphosphatase), dehydroascorbate reductase, peroxiredoxin, malate dehydrogenase, glutamine synthetase, N-glyceraldehyde-2-phosphotransferase, and peptidyl-prolyl cis-trans isomerase were observed to be elevated in the resistant genotype upon pathogen challenge. Increased levels of the antioxidant enzyme superoxide dismutase were further validated and supported by spectrophotometric and in-gel activity assays. Other proteins identified in this study such as nitrate reductase and peptidylprolyl isomerase have not been previously described in this plant-pathogen system, and their potential involvement in an incompatible interaction is discussed.  相似文献   
84.
OBJECTIVE: This study assessed and compared heath-related behaviours and nutrient and food group intakes between US-born and Korea-born Korean American women. DESIGN AND SUBJECTS: Cross-sectional analyses were performed for ethnic Koreans who participated in the Multiethnic Cohort Study in Hawaii and Los Angeles in 1993-1996. The sample included 492 Korean American women aged 45-75 years who were born in the USA (n = 274) or Korea (n = 218). Participants were recruited using driver's license files as a primary sampling source and completed a self-administered questionnaire, including a quantitative food frequency section. RESULTS: The proportion overweight or obese was 31.4% in US-born and 9.4% in Korea-born women. US-born women had higher intakes of total fat and fat as a percentage of energy, and lower intakes of sodium, vitamin C, beta-carotene and carbohydrate as a percentage of energy, than Korea-born women. Comparing intakes of food group servings from the Food Guide Pyramid, US-born women reported more whole grains, red meat and nuts, and less soy products, than did Korea-born women. US-born women also consumed fewer vegetables and fruit than those born in Korea. Few women in either group reported intakes that met the recommendations for dairy foods. Intake of discretionary fat from the Pyramid tip was higher in US-born than in Korea-born women. CONCLUSIONS: These findings indicate that the acculturation of Korean immigrants affects dietary intakes in ways that may alter risks of several chronic diseases. Further studies will be necessary to examine the effects of dietary acculturation on disease patterns.  相似文献   
85.
Protein and oil content were analysed for the seeds of the wild horsegram (IC 212722) belonging to the new species Macrotyloma sar-garhwalensis Gaur and Dangwal. Seed contains 38.37 ± 1.03% crude protein. More than 95% of the total nitrogen belongs to protein nitrogen. Contribution of albumin-globulin, glutelin and residual protein fraction to the total seed protein accounts for 75.27%, 17.52% and 7.19% respectively. The combined albumin-globulin protein (Lowrys protein) fraction of the IC 212722 seed protein contains 16.82% nitrogen, in comparison to 18.19%, 15.82%, 16.81% and 16.42% nitrogen found in a similar part of three cultivated lines of SK-2001, VLG-1, Raipur Local and standard protein (Bovine Albumin Fraction V, Sigma Chemical Co.), respectively studied in the present experiment. The true seed protein (34.88%) content of IC-212722 line was about two times higher than the other three-horsegram lines.IC 212722 line also contains 10.85 ± 0.16% ether extracted materials, in comparison to 0.80–1.47% materials found in the other three-horsegram lines.  相似文献   
86.
The efficacy ofLeucaena leucocephala root litter as a natural biological fertiliser was assessed usingZea mays as a test plant. Up to 8% of the fine roots of the plants constituted root litter. This fine root litter was better than that ofTrigonella foenum-graecum at increasing the growth and productivity ofZea mays. The root litter increased the growth of maize shoots more than the growth of roots. This appears to be a general phenomenon when plant nutrients are insufficient, as in the present study.  相似文献   
87.
Optimal in vitro testing conditions for caprine alternative complement pathway assay were determined. Effects of the following variables were tested: heterologous erythrocytes; pH, ionic strength and Mg2+ ion concentration of the complement diluent; incubation time and temperature. Rabbit erythrocytes were the optimal target cells. The optimal buffer conditions were: pH 8.0, ionic strength 0.06 mmol NaCl and 5mmol Mg2+ ion. Optimal incubation time and temperature were 75 min and 30 degrees C, respectively.  相似文献   
88.
Contribution of the upper laminae designated as 7, 8 and 9 (flag), to the total reduced nitrogen was determined by two different methods; integration of nitrate reductase activity over the entire growing season of individual laminae, and laminae removal at ear emergence. The values obtained by these methods were: 20, 14, and 12 %, and 23, 15, 12 %, respectively. The in vivo nitrate reductase activity was relatively higher in the lamina 9, which contributed an extra 8 % towards total reduced nitrogen when the other laminae were removed from the shoot. No such compensatory response was observed when either lamina 7 or 8 was retained.  相似文献   
89.
OBJECTIVES: To characterise the diet of First Nations in north-western Ontario, highlight foods for a lifestyle intervention and develop a quantitative food-frequency questionnaire (QFFQ). DESIGN: Cross-sectional survey using single 24 h dietary recalls. SETTING: Eight remote and semi-remote First Nations reserves in north-western Ontario. SUBJECTS: 129 First Nations (Oji-Cree and Ojibway) men and women aged between 18 and 80 years. RESULTS: The greatest contributors to energy were breads, pasta dishes and chips (contributing over 20 % to total energy intake). 'Added fats' such as butter and margarine added to breads and vegetables made up the single largest source of total fat intake (8.4 %). The largest contributors to sugar were sugar itself, soda and other sweetened beverages (contributing over 45 % combined). The mean number of servings consumed of fruits, vegetables and dairy products were much lower than recommended. The mean daily meat intake was more than twice that recommended. A 119-item QFFQ was developed including seven bread items, five soups or stews, 24 meat- or fish-based dishes, eight rice or pasta dishes, nine fruits and 14 vegetables. Frequency of consumption was assessed by eight categories ranging from 'Never or less than one time in one month' to 'two or more times a day'. CONCLUSION:We were able to highlight foods for intervention to improve dietary intake based on the major sources of energy, fat and sugar and the low consumption of fruit and vegetable items. The QFFQ is being used to evaluate a diet and lifestyle intervention in First Nations in north-western Ontario.  相似文献   
90.
Significant genetic diversity was observed in 218 out of a total of 1309 accessions of amaranth (Amaranthus hypochondriacus L.) and its seven wild relatives, A. spinosus L., A. dubius Mart. ex Thell., A. hybridus L., A. tricolor L., A. cruentus L., A. caudatus L., A. retroflexus L. for 24 nutritional parameters including total oil content, fatty acid profile, total protein content and amino acid profile. Diversity for total oil content (6.42–12.53%), linoleic acid (25.68–54.34%), oleic acid (21.97–42.01%) of the total fatty acids, total protein content (7.84–18.01%), among important essential amino acids; lysine content (0.66–11.12 g/16 g N), methionine (0.35–4.80 g/16 g N) and half cystine and (0.12–8.32 g/16 g N) was reported. The un-weighted pair-group method using arithmetic average cluster analysis based on pair wise Euclidean genetic distance grouped the accessions into seven major clusters. Histidine, half cystine, tyrosine, essential amino acids, total oil content, linoleic acid and oleic acid content were the major parameters contributing significantly to genetic diversity. Present findings indicate that significant diversity exists for nutritional parameters in amaranth germplasm. The promising accessions with higher multiple nutritive traits; protein content (>16%), oil content (>11%), lysine content (>7.5 g/16 g N) and EAA higher than the FAO reported values, were identified. This is the first report on detailed nutritional analysis of diversity collected worldwide. These could be used as potential breeding material for nutritional enhancement through genetic improvement. This will help in overcoming the “triple burden” of malnourishment, hidden hunger, and obesity.  相似文献   
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