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To improve the breeding of chickpea varieties with resistance to Fusarium wilt, an attempt was made to analyse the biochemical basis of disease resistance by measuring levels of chitinase, β-1,3-glucanase, protease and proteinase inhibitor activities in dry and soaked seeds and in root and shoot tissues of wilt-resistant and wilt-susceptible cultivars. Marginal variation was observed in the levels of the candidate proteins in dry or soaked seeds. Chitinase activity was higher in roots than in shoots or cotyledons. No proteinase inhibitor activity was detected in root and shoot tissue of any of the cultivars. When the levels of these proteins were analysed in resistant (Vijay) and susceptible (JG-62) cultivars during development of wilt by growing plants in soil infested with F. oxysporum f.sp. ciceri , race 1, both cultivars showed induction of chitinase activity in the roots. However, the induced activity in JG-62 (3.82 U g−1 ) was equivalent to the constitutive level in Vijay (3.90 U g−1 ) and much lower than that induced in Vijay (5.18 U g−1 ). Induction of protease activity was observed only in root extracts of Vijay when challenged by the pathogen. The root extract of Vijay showed in vitro antifungal activity in a plate assay. Simultaneous induction of proteolytic and chitinolytic activities specifically in the resistant cultivar was correlated with antifungal properties of root extracts effective in conferring resistance. 相似文献
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The kinetics of the production of interferon gamma (IFN-) in whole blood culture and its comparison with anti-listeriolysin O (ALLO) detection by ELISA were studied during oral infection of calves with Listeria monocytogenes. Culture filtrate antigen (CFA), listeriolysin O (LLO), and sonicated antigen (SA) were used to prime the peripheral blood mononuclear cells (PBMCs) and the plasma from orally infected calves. IFN- and ALLO appeared as early as day 7 of an oral infection. IFN- was detected earlier with LLO than with SA. The Max50 interleukin (IL-2) activity and IFN- estimated in the culture supernatant from PBMCs primed in vitro with different antigens of L. monocytogenes revealed high induction of IL-2 and IFN- by CFA, LLO and live antigen. IFN- assay and ALLO detection were used for testing cases of repeat breeding in dairy cattle. It appeared that detection of IFN- employing LLO can be used to diagnose listerial infections. 相似文献
25.
S.K. Jalota K.B. Singh R.K. Gupta Anil Sood S. Panigrahy 《Agricultural Water Management》2009,96(7):1096-1104
Individual effect of different field scale management interventions for water saving in rice viz. changing date of transplanting, cultivar and irrigation schedule on yield, water saving and water productivity is well documented in the literature. However, little is known about their integrated effect. To study that, field experimentation and modeling approach was used. Field experiments were conducted for 2 years (2006 and 2007) at Punjab Agricultural University Farm, Ludhiana on a deep alluvial loamy sand Typic Ustipsamment soils developed under hyper-thermic regime. Treatments included three dates of transplanting (25 May, 10 June and 25 June), two cultivars (PR 118 inbred and RH 257 hybrid) and two irrigation schedules (2-days drainage period and at soil water suction of 16 kPa). The model used was CropSyst, which has already been calibrated for growth (periodic biomass and LAI) of rice and soil water content in two independent experiments. The main findings of the field and simulation studies conducted are compared to any individual, integrated management of transplanting date, cultivar and irrigation, sustained yield (6.3-7.5 t ha−1) and saved substantial amount of water in rice. For example, with two management interventions, i.e. shifting of transplanting date to lower evaporative demand (from 5 May to 25 June) concomitant with growing of short duration hybrid variety (90 days from transplanting to harvest), the total real water saving (wet saving) through reduction in evapotranspiration (ET) was 140 mm, which was almost double than managing the single, i.e. 66 mm by shifting transplanting or 71 mm by growing short duration hybrid variety. Shifting the transplanting date saved water through reduction in soil water evaporation component while growing of short duration variety through reduction in both evaporation and transpiration components of water balance. Managing irrigation water schedule based on soil water suction of 16 kPa at 15-20 cm soil depth, compared to 2-day drainage, did not save water in real (wet saving), however, it resulted into apparent water saving (dry saving). The real crop water productivity (marketable yield/ET) was more by 17% in 25th June transplanted rice than 25th May, 23% in short duration variety than long and 2% in irrigation treatment of 16 kPa soil water suction than 2-days drainage. The corresponding values for the apparent crop water productivity (marketable yield/irrigation water applied) were 16, 20 and 50%, respectively. Pooled experimental data of 2 years showed that with managing irrigation scheduling based on soil water suction of 16 kPa at 15-20 cm soil depth, though 700 mm irrigation water was saved but the associated yield was reduced by 277 kg ha−1. 相似文献
26.
High frequency and direct (without callus) plant regeneration was achieved from whole leaf explants of thornless blackberry (Rubus hybrid) cv. Black Satin (EC No. 381258; PI No. 553272) in vitro. Leaf blade explants from 1-, 3- and 5-month-old mother cultures were cultured on Murashige and Skoog (MS) medium with thidiazuron (TDZ), N6-benzylaminopurine (BAP), indol-3-butyric acid (IBA) and α-naphthalene acetic acid (NAA), alone or in combination. Three-month explants cultured on 0.02 mg l−1 TDZ produced a high regeneration frequency (91.7%) and the most shoots/leaf explant (17.3). The shoot primordia developed within 3 weeks from the point of detachment of the petiole from the leaf blade. The age of the explant source significantly affected the shoot regeneration potential of the leaf explants. Leaves excised from 3-month-old in vitro-cultured shoots performed better than those from 1- and 5-month-old shoots. Shoots rooted best on half-strength MS basal medium with 0.5 mg l−1 IBA and 90% of the plantlets survived acclimatization. The regenerated plantlets were morphologically similar to the mother plants. 相似文献
27.
The status of cell-mediated immunity (CMI) after pesticide exposure was assessed in mice with the help of skin sensitivity and graft versus host reaction tests. It was observed that at 24 hours post-challenge CMI values did not differ significantly from the control, indicating no effect of quinalphos treatment in mice. Goats receiving monocrotophos at a dose rate of 1.0 mg kg-1 body mass for 40 days gave a similar result when CMI was tested with the help of the chemical sensitizer dinitrofluorobenzene (DNFB). Thus the results clearly indicate that the tested organophosphates do not interfere with cellular immunity in the intoxicated animals. 相似文献
28.
The isolation of 7,4'-dihydroxy-8-methylflavan (1) from the dichloromethane extract of Pancratium littorale stem was guided by an assay for free radical scavenging activity towards the 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH). The structure of 1 was established by spectrometric methods including UV, EI mass spectrometry, 1H and 13C-NMR. The free radical scavenging properties of 1 were quantified in solution using spectrophotometry. 相似文献
29.
The methanol extract of the dried fruit powder of Terminalia pallida was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity. 相似文献
30.
OBJECTIVE: Malnutrition is responsible globally for 60% of deaths among children under 5 years and is often attributed to suboptimal feeding practices. In response, the World Health Organization recommends exclusive breast-feeding for the first 6 months of life. The objective of this study was to determine if an association exists between the early introduction of water and complementary foods (CFs) and the nutritional status of children in northern Senegal. DESIGN/SETTING/SUBJECTS: A cross-sectional study of 374 children in the Podor Health District between the ages of 6 and 23 months was conducted. Knowledge and behaviours of mothers regarding introduction of water and CFs were assessed via individual interviews. RESULTS: Water was introduced to about 85% of the children in the first 3 months of life and 62% were fed CFs before 6 months. Overall, 16% had clinically significant wasting (weight-for-length Z-score (WHZ) less than - 2) and 20% had stunting (height-for-age Z-score (HAZ) less than - 2). There was no significant association between wasting or stunting and introduction of water before 3 months (WHZ: odds ratio = 0.99, 95% confidence interval 0.46-2.14, P = 0.97; HAZ: 0.68, 0.34-1.36, P = 0.3) or introduction of CFs before 6 months (WHZ: 0.81, 0.46-1.42, P = 0.5; HAZ: 0.79, 0.46-1.35, P = 0.4). A significant association was found between wasting and male sex, age, living in Guede community, drinking river/pond water and large family size, while stunting was associated with age and drinking tap water. CONCLUSION: The results of the present study suggest that early introduction of water and CFs is frequent and is not associated with increased risk for malnutrition among children from this region of northern Senegal, but the possibility of reverse causality cannot be excluded. 相似文献