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51.
Soybean cyst nematode, Heterodera glycines Ichinohe, (SCN) populations have been developed which are capable of reproducing on soybean lines known to be resistant to one or more SCN races. Three of the populations developed on PI 88788, PI 90763 and Peking were selected for their differential response on the three hosts. The secondary selection was made on the parent which originally had a high level of resistance. With one exception, secondary selection resulted in increased reproductive ability of the populations on the soybean lines on which they were selected. There was also a corresponding decrease in the reproductive ability on the soybean line on which they were originally developed. The genes from PI 88788, PI 90763 and Peking could be used alternately to provide protection against SCN damage.  相似文献   
52.
53.
The three soybean cultivars, Custer, Pickett 71 and Forrest, which derived their resistance to race 3 of soybean cyst nematode (Heterodera glycines Ichinohe) from the variety Peking, were tested for their level of resistance. Similarly, Bedford, Nathan, D75-10710 and Bradley cultivars which are resistant to race 4 were compared against their donor parent PI 88788. Each soybean line was inoculated with eggs and larvae of known cyst-nematode cultures. Custer, Pickett 71, Forrest and Peking had equal levels of resistance to race 3 and all were equally susceptible to the culture developed on Forrest; however, Peking and Custer had fewer white females against PI 88788 culture than did those on Pickett 71 and Forrest. Among cultivars resistant to race 4, Nathan had a greater number of white females than PI 88788 against cultures developed on Essex, Bedford and Peking. In general, the derived cultivars had a greater number of white females per plant than their donor parents.  相似文献   
54.
The present study was undertaken to antigenically characterize the buffalopox virus (BPV). Six monoclonal antibodies (MAbs) against the BP4 strain of BPV have been produced and characterized. All six MAbs appeared to be specific to BPV, as none of them showed cross-reactivity with other poxviruses in antigen capture ELISA. Only two MAbs (20AB8 and 20CD11) bound significantly with different BPV isolates in antigen capture ELISA, whereas the remaining four MAbs bound weakly with the BPV. In Western blot analysis with purified BPV-BP4, the rabbit hyperimmune serum against purified BPV-BP4 reacted with 15 immunodominant polypeptides (100 kDa to 25 kDa), whereas two MAbs (21CB6, 21DB11) reacted with 42 kDa and 45 kDa polypeptides, respectively. However, three MAbs (20AB8, 20CD11, 21CB5) reacted with three degraded polypeptides (100 kDa, 40 kDa and 87 kDa) of BPV-BP4. In radioimmunoprecipitation assay (RIPA) with the rabbit hyperimmune serum to BPV-BP4, three virus specific polypeptides (69 kDa, 34 kDa, 32 kDa) were recognized in BPV-BP4, whereas two polypeptides (69 kDa, 34 kDa) were recognized in other BPV isolates (BPV-Bly, BPV-Vij96, BPV-Vij97). In virus neutralization test, none of the six MAbs tested showed any significant neutralizing ability to infection with different BPV isolates. However, the hyperimmune serum showed weak neutralizing ability to BPV infection.  相似文献   
55.
Iron deficiency chlorosis (IDC) causes a significant reduction in yield of groundnut grown in calcareous and alkaline soils in India. The main aim of the study was to assess genotypic differences for morpho-physiological parameters associated with IDC resistance across different stages and their effect on yield and its related traits. The factorial pot experiment was comprised of two major factors, i) soil-Fe status [normal-Fe, deficit-Fe], and ii) genotypes [five] with differential IDC response, constituting 10 treatments. They were assessed for five morpho-physiological parameters associated with IDC resistance across five crop growth stages and also yield and its related traits. Associations between these traits were also estimated. Under deficit-Fe conditions, IDC resistant genotypes recorded significantly lower visual chlorosis rating (VCR), higher SPAD values, active Fe, chlorophyll content, peroxidase activity, and high yield compared to susceptible ones. Between normal- to deficit-Fe soils, resistant compared to susceptible genotypes showed no change in VCR scores; a lower reduction in SPAD, chlorophyll, active Fe, peroxidase activity, and pod yield. Under deficit-Fe conditions, high yield among resistant genotypes could be attributed to higher seed weight, number of pods and haulm yield, while contrasting reduction in main stem height and number of primaries. The results indicate that for initial large-scale screening of groundnut genotypes for IDC resistance, SPAD values are most ideal while active Fe could be utilized for confirmation of identified lines.  相似文献   
56.
Poly(1,4-phenylene sulfide) (PPS) exhibits good dimensional stability and flame retardant characteristics but its commercial development as fibers is highly limited due to lesser dyeing and finishing characteristics. Hence in the present study, we focused on the anionic and cationic modifications of PPS to enhance its dyeing ability towards disperse, cationic, and anionic dyes. Novel sulfonation and chloromethylation-quaternization of PPS fiber were carried out to achieve an industrially viable dyeing process methodology. The chemically modified PPS fiber is dyed with disperse, cationic, and anionic dyes, and the dyeing adsorption efficiency is quantitatively studied using a dye-o-meter equipped with UV-visible absorption spectroscope. The ideal parameters for dye adsorption were determined as a function of dyeing time, material-toliquor ratio, dyeing temperature, carrier concentration, sulfonation, and chloromethylation. The fastness properties of the dyed fabrics were also studied. Overall, with a maximum dye uptake of 99 % and 90 % achieved for sulfonated PPS and quaternized PPS respectively, the optimized conditions can be readily scaled-up to the commercial dyeing of PPS fiber with disperse, anionic, and cationic dyes.  相似文献   
57.
OBJECTIVE: The present study was undertaken to assess the impact of drought on the nutritional status of pre-school children aged 0-5 years from a rural population in a desert area facing drought conditions very frequently. DESIGN: The sampling design for assessment was the three-stage sampling technique. SETTING: The study was carried out in 24 villages belonging to six tehsils (sub-units of district) of Jodhpur District, a drought-affected desert district of western Rajasthan, during a drought in 2003. SUBJECTS: A total of 914 children were examined at household level, with nutritional status assessed by anthropometry, dietary intake and clinical signs of nutritional deficiency. RESULTS: The results revealed growth retardation. Stunting (malnutrition of long duration) was observed in 53% of children and underweight in 60%. Wasting, an indicator of short-duration malnutrition, was present in 28% of children. The extent of malnutrition was significantly higher in girls than boys (P<0.05). Vitamin A and B complex deficiencies were found in 0.7 and 3.0% of children, respectively. Prevalence of marasmus (protein-energy malnutrition, PEM) was 1.7% (2.3% in boys and 1.1% in girls). Overall deficits in mean energy and protein intakes were very high (76 and 54%, respectively). Comparison of the present drought results with earlier studies in desert normal and desert drought conditions showed higher prevalence of PEM and higher dietary energy and protein deficiencies. CONCLUSIONS: The prevalence of wasting was high, greater than the cut-off point of 15% stated by the World Health Organization to indicate that the severity of malnutrition is critical. PEM, vitamin A and B complex deficiencies and anaemia, along with dietary deficits of energy and protein, were observed to be higher than in non-desert areas. This may be due to the harsh environmental conditions in desert areas where drought occurs quite frequently and adversely affects the economy, largely by eroding the coping capacity and economic potential of the people as a result of heavy livestock losses and reduced harvests, leading to increased poverty and poor food intake of the inhabitants. Due to inadequate consumption of daily food the children were suffering from wasting and PEM. Efforts should be made to incorporate measures, such as ensuring the supply of adequate energy and protein to all age groups and especially pre-school children, into ongoing nutrition programmes in order to improve the food security of local inhabitants in this area.  相似文献   
58.
Paddy and Water Environment - A two-stage rainwater conservation technique was intervened in the farmers field of rainfed shallow low land, in which, part of the rainwater is conserved in rice...  相似文献   
59.
AGTR2 mutations in X-linked mental retardation   总被引:1,自引:0,他引:1  
Two angiotensin II (Ang II)-specific receptors, AGTR1 and AGTR2, are expressed in the mammalian brain. Ang II actions on blood pressure regulation, water electrolyte balance, and hormone secretion are primarily mediated by AGTR1. The function of AGTR2 remains unclear. Here, we show that expression of the AGTR2 gene was absent in a female patient with mental retardation (MR) who had a balanced X;7 chromosomal translocation. Additionally, 8 of 590 unrelated male patients with MR were found to have sequence changes in the AGTR2 gene, including one frameshift and three missense mutations. These findings indicate a role for AGTR2 in brain development and cognitive function.  相似文献   
60.
A survey was conducted for the nutritional status of aonla orchards in the state of Uttar Pradesh lying in Central Indo-Gangetic plains. Preliminary diagnosis and recommendation integrated system (DRIS) norms were established for different nutrient ratios and used to compute the DRIS indices, which assessed the nutrient balance and order of limitations to yield. Maximum fruit yield of 40.2 kg plant?1 was recorded for the plants at the age group of 10–15 years and lowest yield was recorded 28.3 kg plant?1 in the age of above 20 years. Nutrient sufficiency ranges for aonla derived from DRIS norms were 1.30– 1.64, 0.054–0.092, 0.40–0.64%, and 32.4–45.9 ppm for nitrogen (N), phosphorus (P), potassium (K), and zinc (Zn), respectively. On the basis of these sufficiency ranges 33, 51, 47, and 46% of samples were found sufficient whereas 34, 22, 18 and 27% of samples were low and 26, 8, 1 and 17% deficient in N, P, K, and Zn, respectively. When compared age wise, a relative deficiency for N, P, and K corresponding to relative sufficiency for Zn was detected by DRIS technique for the plants above the age group of 15 onwards. For the younger orchards (5yrs old) a relative deficiency of N, Zn, and K corresponding to the relative sufficiency of P was detected. Nitrogen was found most limiting elements in all age group of plant. When the DRIS indices were compared on basis of soil pH, Zn and K was found to be relatively lesser in order of requirement than N and P.  相似文献   
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