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131.
Wheat planting in rice-harvested fields without land preparation is more economical, but the physical characteristics of the plant root sphere are not well documented. Comparative changes in the soil compaction in parallel fields used for no-till and conventional tillage were measured in replicated field trials for two soil types and in three randomly selected farmers’ fields. Weakly to moderately developed soils on recent to old Pleistocene calcareous alluvium were studied. They differed in their clay content. No-till wheat sowing resulted in a greater soil bulk density and a lower total porosity in the heavy-textured soils compared to the light-textured soil. In the light-textured Jhakkar soil, the no-till regime resulted in a greater infiltration at the saturated state and under most suction levels and a greater macroporosity compared to the conventional tillage. The silty clay Kotly soil had greater macroporosity in the conventional tillage than in the no-till regime. The wheat root growth and penetration seemed to be favored by the relatively low bulk density resulting from the conventional tillage, particularly in the silty clay loam soil. The dense layer restricted root penetration in the silty clay loam soil, while there was less resistance in the sandy loam soil. The study demonstrated the suitability of the no-till regime for specific soil types. Published in Russian in Pochvovedenie, 2008, No. 11, pp. 1362–1370. The text was submitted by the authors in English.  相似文献   
132.
Antagonistic fungi (Aspergillus niger CA and Penicillium chrysogenum CA1), plant growth-promoting rhizobacteria (PGPR) (Burkholderia cepacia 4684 and Bacillus subtilis 7612) and AM fungi (Glomus intraradices KA and Gigaspora margarita AA) were assessed alone and in combination for their effects on the growth of tomato and on the reproduction of Meloidogyne incognita in glasshouse experiments. Application of antagonistic fungus, PGPR, or AM fungus alone or in combination significantly increased the length and shoot dry mass of plants both with and without nematodes. The increase in shoot dry mass caused by Gl. intraradices KA in plants without nematodes was greater than that caused by PGPR or antagonistic fungi. Similarly, the increase in shoot dry mass caused by Bu. cepacia 4684 in plants with nematodes was greater than that caused by P. chrysogenum CA1. Application of Bu. cepacia 4684 caused a 36.1% increase in shoot dry mass of nematode-inoculated plants followed by Ba. subtilis 7612 (32.4%), A. niger CA (31.7%), Gl. intraradices KA (30.9%), Gi. margarita AA (29.9%) and P. chrysogenum CA1 (28.8%). Use of Bu. cepacia 4684 with A. niger CA caused a highest (65.7%) increase in shoot dry mass in nematode-inoculated plants followed by Ba. subtilis 7612 plus A. niger CA (60.9%). Burkholderia cepacia 4684 greatly reduced (39%) galling and nematode multiplication, and the reduction was even greater (73%) when applied with A. niger CA. Antagonistic fungi had no significant effect on root colonization caused by AM fungi. Applying Bu. cepacia 4684 with A. niger CA may be useful in the biocontrol of M. incognita on tomato.  相似文献   
133.
Experimental trials were conducted at Integrated Pest Management Programme, National Agriculture Research Centre Islamabad, to evaluate the resistance of host plants (cereals) against Rhopalosiphum padi (L.). For evaluation of susceptibility, twenty varieties/-advanced lines of National Uniform Wheat Yield Trails (NUWYT) Normal (N) of year 2004-2005 were used. In seedling bulk tests varieties/advanced lines were grouped into three categories resistant, moderately resistant and susceptible. Data from seedling bulk tests showed that DN-47 and PR 87 lines of wheat were resistant to aphid as compared to the other varieties/-advanced lines. In antixenosis tests varieties/-advanced lines were grouped into three categories, least preferred, moderately preferred, highly preferred. Lines V-01180, DN-47 and PR-84 were least preferred, sixteen varieties/-advanced lines were moderately preferred and only one variety V-9021 was found to be highly preferred.  相似文献   
134.
In this paper, we report the development, characterization and bioefficacy evaluation of fipronil nanoformulations against brown plant hopper (BPH); Nilaparvata lugens in rice. Nanoformulations were characterized for nanosizing and stability under variable conditions. Bioefficacy of nanoformulations were evaluated under field condition at farms of Indian Agricultural Research Institute, New Delhi during Kharif 2015. At milking stage BPH populations were above economic threshold level; followed by foliar application of fipronil nanoformulations at four doses (viz., 30, 45, 60 and 90 g a.i./ha) along with commercial formulation of fipronil. The mean mortality clearly indicated that all the insecticidal treatments were significantly superior over untreated control where, highest mortalities were observed in nanodispersions followed by monolithic dispersion and commercial formulation of fipronil. Treated plots 7 days after application @ 60 g a.i./ha has shown 93.47%, 86.89% and 80.47% reduction BPH population in nanodispersion, encapsulated monolithic dispersion and commercial formulation treated plots respectively. In comparison to commercial formulation @ 60 g a.i./ha yield has increased by 0.56 t ha?1 (28.76%) and 0.26 t ha?1 (14.04%) in nanodispersion and monolithic dispersion.  相似文献   
135.
Biochar amendments offer promising potential to improve soil fertility, soil organic carbon (SOC) and crop yields; however, a limited research has explored these benefits of biochar in the arid and semi‐arid regions. This two‐year field study investigated the effects of Acacia tree biomass‐derived biochar, applied at 0 and 10 t ha?1 rates with farmyard manure (FYM) or poultry manure (PM) and mineral phosphorus (P) fertilizer combinations (100 kg P ha‐1), on maize (Zea mays L.) productivity, P use efficiency (PUE) and farm profitability. The application of biochar with organic–inorganic P fertilizers significantly increased soil P and SOC contents than the sole organic or inorganic P fertilizers. Addition of biochar and PM as 100% P source resulted in the highest soil P (104% increase over control) and SOC contents (203% higher than control). However, maize productivity and PUE were significantly higher under balanced P fertilizer (50% organic + 50% mineral fertilizer) with biochar and the increase was 110%, 94% and 170% than 100%‐FYM, 100%‐PM and 100% mineral fertilizer, respectively. Maize productivity and yield correlated significantly positively with soil P and SOC contents These positive effects were possibly due to the ability of biochar to improve soil properties, P availability from organic–inorganic fertilizers and SOC which resulted in higher PUE and maize productivity. Despite the significant positive relationship of PUE with net economic returns, biochar incorporation with PM and mineral fertilizer combination was economically profitable, whereas FYM along biochar was not profitable due to short duration of the field experiments.  相似文献   
136.
A sixty-day feeding trial was carried out to elucidate the effect of dietary pyridoxine (PN) on hemato-immunological parameters in Labeo rohita fingerlings exposed to an elevated temperature (ET) of 33 °C. Two hundred and seventy fingerlings (6.71 ± 0.32 g) were randomly distributed into six treatments in triplicates (15 fish/tank). Five iso-nitrogenous (356.3 ± 2.7 g/kg crude protein) purified diets were prepared with graded levels (0, 10, 50, 100 and 200 mg/kg diet) of PN. Six treatment groups were P10T26 (10 mg PN + ambient temperature (26 °C), P0T33 (0 mg PN + ET), P10T33 (10 mg PN + ET), P50T33 (50 mg PN + ET), P100T33 (100 mg PN + ET) and P200T33 (200 mg PN + ET). The responses of L. rohita fingerlings to dietary PN were assessed in terms of growth and by analysing some hemato-immunological parameters. When PN supplementation increased from 10 to 200 mg/kg diet, a significant improvement in weight gain percentage was observed. Erythrocyte (RBC) count, leucocyte (WBC) count, haemoglobin content and respiratory burst activity were significantly (p < 0.05) higher in 100 mg PN/kg diet-fed group than their non-PN-fed counterpart. Also, serum albumin, globulin and lysozyme activity were found significantly (p < 0.05) higher in PN-fed groups. The overall results indicated that dietary PN supplementation at 100 mg/kg diet may reverse the negative effects caused by ET and may protect the haemato-immunological status of L. rohita fingerlings reared at higher water temperature.  相似文献   
137.
Introduction The uniform distribution of collagen fibrils and proteoglycans maintain the transparency of normal cornea. We describe the ultrastructural features of camel cornea including collagen fibrils and proteoglycans (PGs). Methods Camel corneas (of 6‐, 8‐, and 10‐month‐old animals) were fixed in 2.5% glutaraldehyde containing cuprolinic blue in sodium acetate buffer and processed for electron microscopy. The ‘AnalySIS LS Professional’ program was used to analyze the collagen fibril diameter. Results The camel cornea consists of four layers: the epithelium (227 μm), stroma (388 μm), Descemet’s membrane (DM), and endothelium. The epithelium constituted 36% of the camel cornea, whereas corneal stroma constituted 62% of the corneal thickness (629 μm). The PGs in the posterior stroma were significantly larger in number and size compared with the anterior and middle stroma. The collagen fibril diameter was 25 nm and interfibrillar spacing 40 nm. Fibrillar structures are present throughout the DM. Conclusion The structure of the camel cornea is very different from human and other animals. The unique structure of the cornea might be an adaptation to help the camel to survive in a hot and dry climate. The camel cornea may also be a good model to study the effect of hot and dry climates on the cornea.  相似文献   
138.
This paper reports the immunostimulatory and protective effects of Aloe vera extracts (aqueous and ethanolic) against coccidiosis in industrial broiler chickens. The study was divided into two experiments. Experiment-I was conducted for the evaluation of immunostimulatory activity of A. vera and experiment-II demonstrated the protective efficacy of A. vera extracts against coccidiosis in chickens. Results of the experiment-I revealed significantly higher (p<0.05) lymphoproliferative responses in chickens administered with ethanolic extract of A. vera as compared to those administered with aqueous extract and control group. Microplate haemagglutination assay for humoral response on day 7th and 14th post primary and secondary injections of sheep red blood cells (SRBCs) revealed significantly higher (p<0.05) anti SRBC antibody (total Igs, IgG and IgM) titers in chickens of experimental groups as compared to the control group. None of the extracts, however, demonstrated significant effects on the development of lymphoid organs. Results of experiment-II revealed maximum protection (60%) in chickens administered with aqueous Aloe extract as compared to the ethanolic extract administered chickens (45%). Mean oocysts per gram of droppings in the control group was significantly higher (p<0.05) as compared to the chickens in both the experimental groups. Chickens administered with aqueous Aloe extract showed a minimal mean lesion score (2.3) followed by those administered with ethanolic Aloe extract (2.6) and control chickens (3.05) for caeca, and a similar pattern was observed for intestinal lesion scoring. Further, significantly higher weight gains and antibody titers (p<0.05) were observed in chickens administered with A. vera extracts as compared to those in the control group. It was concluded that A. vera may be a potential and valuable candidate to stimulate the immune responses and can be used successfully as an immunotherapeutic agent against coccidiosis in industrial broiler chickens.  相似文献   
139.
A study was made in the net house of Plant Physiology, Department of Botany, Aligarh Muslim University, Aligarh to study the comparative effect of wastewater and groundwater along with three different rates of nitrogen (N) of 0, 30, and 60 kg ha?1 on growth, physiology and yield of two varieties of chilli cv. ‘G4’ and ‘Pusa Jawala’. Wastewater irrigation resulted significant increase in shoot and root length, fresh weight, dry weight, leaf number and area, net photosynthetic rate (PN), stomatal conductance (gs), water use efficiency (WUE), chlorophyll content, and yield. The physio-chemical parameters of wastewater met the irrigational characteristics, being well within the permissible limit as outlined by the Food and Agriculture Organization. Among the nitrogen doses 30 kg ha?1 N along with wastewater proved best for the growth and yield. Thus it may be concluded that wastewater reduced the demand of fertilizers and it may be used for the cultivation of chilli.  相似文献   
140.
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