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1.
A field experiment was carried out for 2 crop years (July‐October) at the Indian Agricultural Research Institute, New Delhi to study the effect of land configuration and phosphorus levels on the growth and yield of rainy season greengram under limited irrigation facility. The crop sown on 2 meter wide broad bed and furrow (BBF) showed higher growth attributes, nodulation, yield attributes and yield compared to flat bed (FB) sowing. Application of 30 and 60 kg P2O5ha‐1 showed significant increase in growth attributes, nodulation, yield attributes and yield as compared to no phosphorus application. The moisture status in the soil determined the optimum dose of phosphorus needed for greengram. The combination of BBF sowing and application of 60 kg P2O5 ha?1 recorded the highest grain yield among all the combinations of land configuration and phosphorus levels.  相似文献   
2.
(1) Two hundred and twenty-seven adult turkeys of both sexes, of two varieties (104 Black and 123 White) were used to evaluate their immunocompetence status and body weights. (2) Response to sheep red blood cells (SRBC) (humoral immunity) was measured by Haemagglutination (HA) test 5 days post immunisation (dpi) and expressed as log2 values. Mercaptoethanol resistant (MER) antibodies representing IgG were determined by Mercaptoethanol HA test and Mercaptoethanol sensitive (MES) antibodies, representing IgM as the difference in total HA titre and IgG. Serum lysozyme concentrations were estimated by 'Lysoplate assay' and expressed in log2 values. (3) Least squares analysis of variance revealed that the White variety had higher adult body weight (4.788 +/- 0.040 kg) than the Black (3.774 +/- 0.044 kg). Sexual dimorphism was apparent and meals were heavier than females in both varieties. The interaction effect of variety and sex on body weight was also significant. (4) Least squares means for immunological traits, namely, total anti-SRBC antibodies, MER, MES titres and serum lysozyme were 7.161 +/- 0.189, 0.801 +/- 0.071, 6.362 +/- 0.160 and 1.766 +/- 0.043 microg/ml, respectively. The Black variety had a higher MES antibody titre than the White. (5) Sex had an effect on all the immunological traits except on MER titres. Females generally had higher anti-SRBC, MER and MES titres and serum lysozyme. The variety x sex interaction effect was significant for MES titres and serum lysozyme. White males had the lowest MES titres.  相似文献   
3.
Three hundred and three chicks of both sexes, from a synthetic dam line (SDL) of broiler chickens, were studied for economic traits (body weights at 4, 5 and 6 weeks of age) and immunological traits (humoral and cell mediated immune responses, and serum lysozyme concentration). The objective was to evaluate these traits and to estimate their genetic and non-genetic parameters. The humoral immune response was assessed by estimating the antibody response to sheep red blood cells using the haemagglutination (HA) test and serum IgG concentration using single radial immunodiffusion (SRID). The cell mediated immune (CMI) response was estimated as in vivo response to a mitogen (PHA-P). Serum lysozyme was measured by lysoplate assay. Least squares means for body weight at 4, 5 and 6 weeks were 684 +/- 20, 920 +/- 19 and 1205 +/- 28 g, HA titre was 6.289 +/- 0.246, CMI was 0.438 +/- 0.015 mm, lysozyme was 1.860 +/- 0.047 microg/ml and IgG was 6.287 +/- 0.194 mg/ml. There was an effect of sire on HA titre and on body weight at 4, 5 and 6 weeks of age; males were heavier than females. Heritability estimates were high for body weights but low for immunological traits. Phenotypic correlations (rp) among body weights were high and positive but were very low between body weights and most immunological traits. Among the immunological traits all rp were very low. Genetic correlations (rg) of body weights were positive and medium to high with CMI and HA and negative with serum IgG.  相似文献   
4.

Background

Rice (Oryza sativa L.) is the staple food for more than 3.5 billion people, mainly in Asia. Brown planthopper (BPH) is one of the most destructive insect pests of rice that limits rice production. Host-plant resistance is one of the most efficient ways to overcome BPH damage to the rice crop.

Results

BPH bioassay studies from 2009 to 2015 conducted in India and at the International Rice Research Institute (IRRI), Philippines, revealed that the cultivar CR2711–76 developed at the National Rice Research Institute (NRRI), Cuttack, India, showed stable and broad-spectrum resistance to several BPH populations of the Philippines and BPH biotype 4 of India. Genetic analysis and fine mapping confirmed the presence of a single dominant gene, BPH31, in CR2711–76 conferring BPH resistance. The BPH31 gene was located on the long arm of chromosome 3 within an interval of 475 kb between the markers PA26 and RM2334. Bioassay analysis of the BPH31 gene in CR2711–76 was carried out against BPH populations of the Philippines. The results from bioassay revealed that CR2711–76 possesses three different mechanisms of resistance: antibiosis, antixenosis, and tolerance. The effectiveness of flanking markers was tested in a segregating population and the InDel type markers PA26 and RM2334 showed high co-segregation with the resistance phenotype. Foreground and background analysis by tightly linked markers as well as using the Infinium 6 K SNP chip respectively were applied for transferring the BPH31 gene into an indica variety, Jaya. The improved BPH31-derived Jaya lines showed strong resistance to BPH biotypes of India and the Philippines.

Conclusion

The new BPH31 gene can be used in BPH resistance breeding programs on the Indian subcontinent. The tightly linked DNA markers identified in the study have proved their effectiveness and can be utilized in BPH resistance breeding in rice.
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5.
We assessed soil fungal diversity in the dry deciduous forest of a Bhadra Wildlife Sanctuary of the Western Ghats(210.31 m a.s.l.;N 13°44’ and E75°37’).Soil samples were collected by random mixed sampling during winter(November,2008),summer(March,2009) and monsoon(August,2009) seasons,and physico-chemical parameters were recorded.During winter,summer,and monsoon seasons,49,45 and 49 of fungal species belongs to 20,18 and 19 of genera were isolated,respectively.Isolated soil fungi were mainly of the Mitosporic fungi,followed by Zygomycotina,Ascomycotina,Oomycotina and Coelomycetes.Indices of diversity,dominance and fisher alpha during winter,summer and monsoon seasons were 3.756,3.638 and 3.738(H’),0.9737,0.9694 and 0.9726(1-D) and 18.84,29.83 and 19.46(α),respectively.Spearman’s(r) correlation coefficient of fungal population with physico-chemical parameters of soils showed significantly positive and negative correlations(p<0.01) during winter,summer and monsoon seasons.Physico-chemical soil parameters played an important role in the occurrence,diversity,distribution,and relative abundance of fungal species in the tropical dry deciduous forest soil.  相似文献   
6.

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.

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7.
Tissue homogenates of pearl millet seedlings (cultivars HB 3, 843 B, ICMP 451 and IP 18292), with varying degree of resistance to downy mildew disease were tested for ribonuclease (RNase) enzyme activity and the profile of major RNase isozymes by substrate based gel assay. Polyacrylamide gel electrophoresis (PAGE) of the four pearl millet homogenates revealed 15–20 isozymes, varying in size from 6.5 to 121.0kDa. Most of the RNases were highly active between pH 6 and 8 with maximum activity at pH 7. Tissue specific expression of RNase was observed with more activity in the root, i.e., 38.84, 59.61, 39.90 and 49.23 units in HB 3, 843 B, ICMP 451 and IP 18292, respectively than in shoot 11.54, 9.95, 9.46 and 9.49 units in HB 3, 843 B, ICMP 451 and IP 18292, respectively. Effect of metal ions on the RNase profile indicates Zn++ at 2, 20 and 200M concentrations to be inhibitory. Ca++ and Mg++ at 1mM concentration enhanced the enzyme activity while at 10mM inhibition of enzyme activity was observed. Inoculation with the downy mildew pathogen Sclerospora graminicola reduced RNase activity by 4–13% in compatible interactions while in incompatible combinations, the enzyme activity increased by 10–27%. The significance of RNase in pearl millet-downy mildew interaction and its involvement of in systemic acquired resistance of pearl millet against the downy mildew pathogen are discussed.  相似文献   
8.
Hybrid rice based on wild‐abortive cytoplasmic male sterility (WA‐CMS) is important in boosting rice production, which requires diverse parents to harness heterosis. For this, exploiting the diversity of japonica through tropical japonica (TRJ) lines is an excellent route. In this study, 310 TRJ‐based new plant type (NPT) lines were developed and evaluated for Rf3 and Rf4 genes. Gene‐based (DRRM‐Rf3‐5 and DRRM‐Rf3‐10) and functional marker (RMS‐SF21‐5) targeted Rf3 locus, while gene‐linked (RM6100) and functional marker (RMS‐PPR9‐1) targeted the Rf4 locus. The frequency of the restorer allele of Rf3 gene was lower when compared to that of Rf4. Combined phenotypic and molecular screening using gene‐based and functional markers identified 42 lines that carried Rf3 and/or Rf4 genes. All the selected lines produced fertile F1s when crossed to a WA‐CMS line, “Pusa 6A”, but with varying levels of spikelet fertility. This is the first report of a marker‐cum‐phenotype‐based restorer selection using TRJ‐derived lines. Multilocation evaluation of these lines at three locations indicated better adaptation for grain yield in some of the lines.  相似文献   
9.
Thirty-one tropical japonica derived Rf gene carrying rice hybrids were classified into three classes as Rf3, Rf4 and Rf3 + Rf4 hybrids. These hybrids were tested under three different mega-environments. Between Rf3 class and both the classes of hybrids possessing Rf4 genes, significant variation for spikelet and pollen fertility and grain yield was found. The pollen fertility was five times higher among Rf4 hybrids than that of hybrids carrying Rf3 alone. Likewise, spikelet fertility among Rf4 hybrids was two times higher than that of Rf3 hybrids. Parallel grain yield increase in Rf4 hybrids was 2.4 times than in Rf3 hybrids. However, Rf3 gene was found complementing Rf4 to truncate the range of pollen and spikelet fertility. Hybrids possessing Rf3 alone exhibited partial pollen and spikelet sterility, and significant negative standard heterosis for grain yield. The high yielding hybrid, “HYB36” carrying both the Rf genes was found to be widely adapted. The present study established that Rf4 gene is essential either alone or in combination with Rf3 for fertility restoration to achieve enhanced grain yield in WA-CMS based hybrids.  相似文献   
10.
Veterinary Research Communications - Livestock plays a significant role in the socio-economic development of developing countries by providing livelihood and nutritional security, transport,...  相似文献   
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