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81.
One approach to improve cotton (Gossypium hirsutum L.) yield is to identify stable genotypes for low or no bollworms damage as it accounts low cost of cultivation to a considerable
extent. The objective of the study was to identify stable genotypes for low bollworms damage under protected and unprotected
experiments. Fifty cotton (Gossypium hirsutum L.) genotypes were evaluated for open bollworms damage percent (spotted, pink and Heliothis bollworms) for 3 years during 2003–2005 under protected and unprotected conditions. Variance due to genotypes, environments,
genotype × environment and genotype × environment (linear) components were highly significant for the trait in protected and
unprotected experiments. Under protected experiment, genotypes CSH 3020 and 3045 were found to be desirable and stable while
genotype CSH 3058 was suited for poor environments. Fourteen genotypes viz. CSH 3034, 3035, 3043, 3044, 3047, 3051, 3053,
3058, 3059, 3094, 3106, 3114, 3123 and CSH-3157 were fairly stable under unprotected environments. The study lead to the conclude
that in general for the two experiments the genotypes differed for stability for low bollworms damage. 相似文献
82.
A.K. Shasany R.K. Lal N.K. Patra M.P. Darokar A. Garg S. Kumar S.P.S. Khanuja 《Genetic Resources and Crop Evolution》2000,47(5):553-559
The species Cymbopogon winterianus Jowitt is believed to have originated from the well-known species Cymbopogon nardus, type Maha Pengiri, referred to as Ceylonese (Sri Lankan) commercial citronella. Cymbopogon winterianus Jowitt was named after Winter, who raised its population as a separate species in the 19th century. C. winterianus was introduced into Indonesia and became commercially known as the Javanese citronella. The Javanese type C. winterianus material was introduced into India for the commercial cultivation of this crop during 1959. Varieties of this species have been developed later by the use of breeding procedures from the same introduced material. A comparative analysis of yields of herb, oil percentage and oil constituents for eight prevalent C. winterianus cultivars comparing them between themselves as well as against an accession of C. nardus has been carried out. All these accessions were analyzed at the molecular level for the similarity and genetic distances through RAPD profiling, using 20 random primers. More than 50% divergence was observed for all the C. winterianus accessions in relation to C. nardus accession CN2. The clustering based on the similarity matrices showed a major cluster of six accessions, consisting of two sub-clusters. The accession C. nardus CN2 got carved out along with two C. winterianus accessions, CW2 and CW6. On the other hand, the accessions CW2 and CW6 demonstrated distinct identities compared to CN2 at the DNA level. 相似文献
83.
B. Lal D. S. Rajput M. B. Tamhankar I. Agarwal M. S. Sharma 《Journal of Agronomy and Crop Science》2003,189(2):57-62
An assessment of the energy requirements of different intensive forage production systems was carried out at the Indian Grassland Fodder, and Agroforestry Research Institute, Jhansi. This included assessment of energy use and output for five intensive crop production systems: (1) sorghum (single‐cut)–berseem, (2) cowpea–sorghum (single‐cut)–berseem + mustard–maize + cowpea, (3) sorghum (multi‐cut)–berseem + oats, (4) guar–oats–maize and (5) sorghum (single‐cut)–wheat–fallow. In all the systems, the Napier bajra hybrid (IGFRI‐3) was transplanted in regular plots of 50 m × 13 m. Results revealed that the total annual energy use was highest for sorghum (multi‐cut)–berseem + oats (36 606 MJ ha?1), followed by sorghum (single‐cut)–berseem + mustard, sorghum (single‐cut)–berseem–cowpea, guar–oats–maize and sorghum (single‐cut)–wheat–fallow (for which values were 31 086, 30 449, 29 867 and 25 956 MJ energy ha?1, respectively). The high value found for sorghum (multi‐cut)–berseem + oats might be attributable to the multi‐cuts in this system. Energy use by fertilizers represented the major part of the total energy use, amounting to 28–38 % in all treatments, followed by energy used in electricity, machinery, seeds, human labour and farmyard manure (FYM), in case of all with slight increase in input. In sorghum–wheat, energy use by seeds occupied the second position, followed by energy used in electricity, human labour, FYM and machinery/diesel. Pesticides contributed the least energy utilization in all the treatments. Herbicides were used for the control of weeds. Among the five forage production systems, sorghum (single‐cut)–berseem + mustard–maize + cowpea was found to be the most energy efficient, followed by sorghum (multi‐cut)–berseem + oats–sorghum (multi‐cut), sorghum (single‐cut)–berseem–cowpea, guar–oats–maize and sorghum (single‐cut)–wheat–fallow. Sorghum (single‐cut)–berseem + mustard–maize + cowpea increased the fertility of the soil, resulting in a higher percentage of organic carbon, higher availability of nitrogen and optimal balancing of the C:N ratio in the upper layers of the soil. These intensive crop production systems also maintain the optimum microbial population in the crop root zone. The benefit–cost ratio (B:C ratio) for the most energy‐efficient forage production system was 1.37 : 1. However, the highest B:C ratio was found in the sorghum–wheat rotation (1: 1.57). 相似文献
84.
R. Raina S. Prawez D.J. Dimitrova N.K. Pankaj P.K. Verma 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):241-245
We evaluated the pharmacokinetics of ciprofloxacin in serum (n = 6) and urine (n = 4) in goats following a single intravenous administration of 4 mg/kg body weight. The serum concentration-time curves of ciprofloxacin were best fitted by a two-compartment open model. The drug was detected in goat serum up to 12 h. The elimination rate constant (β) and elimination half-life (t1/2β) were 0.446 ± 0.04 h-1 and 1.630 ± 0.17 h, respectively. The apparent volume of distribution at steady state (Vdss) was 2.012 ± 0.37 l/kg and the total body clearance (ClB) was 16.27 ± 1.87 ml/min/kg. Urinary recovery of ciprofloxacin was 29.70% ± 10.34% of the administered dose within 36 h post administration. In vitro serum protein binding was 41% ± 13.10%. Thus, a single daily intravenous dose of 4 mg/kg is sufficient to maintain effective levels in serum and for 36 h in urine, allowing treatment of systemic, Gram-negative bacterial infections and urinary tract infections by most pathogens. 相似文献
85.
Parmeshwar Lal Saran Ravish Choudhary Ishwar Singh Solanki Sezai Ercisli 《Erwerbs-Obstbau》2016,58(3):199-202
The effect of temperature on germination and days taken for germination was evaluated in Carica papaya cvs., ‘Pune selection-3’ and ‘Pusa Dwarf’. The highest average seed germination per cent was observed in the month of July (96.8 and 93.0?%), followed by August (94 and 88.5?%), whereas the lowest average seed germination was observed in the month of January (44.2 and 36.8?%) in ‘Pune selection-3’ and ‘Pusa Dwarf’, respectively. Minimum number of days (5.17 and 6.33) was observed for germination in the month of July, whereas the maximum number of days (29.5 and 31) was taken in the month of January in both the cultivars, respectively. The average highest germination and seedling height was observed at temperature 29.8 °C and 29.5 °C during July and August, respectively, whereas the lowest was observed at temperature 14 °C and 15.9 °C during January and December, respectively. The optimum time for nursery sowing was July to August for autumn season crop under subtropical conditions of India. 相似文献
86.
Soil erosion is widespread in agricultural lands of the US Corn Belt. The objective of this study was to examine the impact of antecedent erosion on loss of soil under laboratory simulated rainfall. The soil was obtained from the surface layer of eroded (ER) and uneroded (UN) sites within a conservation agro‐ecosystem in central Ohio, USA. Air‐dried soil was subjected to a rainfall simulation for 60 min (dry run), and to another simulation (wet run) 24 h after the dry run. In the dry run, the cumulative water runoff, sediment yield, and soil organic carbon loss were higher in ER (12.3 L/m2, 169.3 g/m2, and 5.6 g/m2, respectively) than in the UN (7.3 L/m2, 22.6 g/m2, and 0.9 g/m2 respectively). An opposite trend was observed for the cumulative water infiltration (0.9 and 3.9 L/m2, respectively). In the wet run, despite a similar cumulative water runoff from the two erosional phases (20.1 and 19.6 L/m2 in ER and UN respectively), sediment yield and soil organic carbon loss were higher in ER (484.4 g/m2, and 16.3 g/m2 respectively) than in the UN (146.6 g/m2, and 5.3 g/m2 respectively). Also for the wet run, an opposite trend was observed for the cumulative infiltration (0.8 and 5.8 L/m2 respectively). This study suggests that past erosional processes increase the susceptibility of remaining soil to accelerated erosion. 相似文献
87.
Natural 13C abundance and soil carbon dynamics under long‐term residue retention in a no‐till maize system 下载免费PDF全文
Residue retention and reduced tillage are both conservation agricultural practices that may enhance soil organic carbon (SOC) stabilization in soil. We evaluated the long‐term effects of no‐till (NT) and stover retention from maize on SOC dynamics in a Rayne silt loam Typic Hapludults in Ohio. The six treatments consisted of retaining 0, 25, 50, 75, 100 and 200% of maize residues on each 3 × 3 m plot from the crop of previous year. Soil samples were obtained after 9 yrs of establishing the experiment. The whole soil (0–10 and 10–20 cm of soil depths) samples under different treatments were analysed for total C, total N, recalcitrant C (NaOCl treated sample) and 13C isotopic abundance (0–10 cm soil depth). Complete removal of stover for a period of 9 yrs significantly (P < 0.01) decreased soil C content (15.5 g/kg), whereas 200% of stover retention had the maximum soil C concentration (23.1 g/kg). Relative distribution of C for all the treatments in different fractions comprised of 55–58% as labile and 42–45% as recalcitrant. Retention of residue did not significantly affect total C and N concentration in 10–20 cm depth. 13C isotopic signature data indicated that C4‐C (maize‐derived C) was the dominant fraction of C in the top 0–10 cm of soil layer under NT with maize‐derived C accounting for as high as 80% of the total SOC concentration. Contribution of C4‐C or maize‐derived C was 71–84% in recalcitrant fraction in different residue retained plots. Residue management is imperative to increase SOC concentrations and long‐term agro‐ecosystem necessitates residue retention for stabilizing C in light‐textured soils. 相似文献
88.
In India, a single soil loss tolerance ( T ) value of 11.2 Mg/ha is by default used for formulating land restoration strategies for all soil types, climates and vegetation covers. However, this single 'T' value does not represent a true picture of soil loss tolerance under all land uses. The objective of our study was to develop adjusted ' T ' values for Central India using soil infiltration rate, bulk density, total organic carbon, erodibility and soil pH. Soil state was defined using a quantitative model involving different soil functions which were used to convert soil parameters to a 0 to 1 scale. The normalized values were then multiplied by appropriate weighing factors based on relative importance and sensitivity analysis of each indicator. Based on overall assessment, each soil mapping unit was categorized into soil groups I, II or III. A general guideline of USDA – Natural Resource Conservation Service (USDA-NRCS) was followed to calculate soil loss tolerance for each soil group using effective soil depth. Adjusted ' T ' values for Central India ranged from 2.5 to 12.5 Mg/ha compared with a default value of 11.2 Mg/ha. Use of these values for soil mapping units will improve conservation planning and assist with planning the development of sustainable agriculture. 相似文献
89.
The possible anti-inflammatory activity of the 90% ethanolic extract of Dalbergia sissoo leaves (DSELE) was studied in different models of inflammation in rats after oral administration at doses of 100, 300 and 1000 mg/kg. DSELE significantly inhibited carrageenin, kaolin and nystatin-induced paw oedema, as well as the weight of granuloma induced by a cotton pellet. It also inhibited dye leakage in acetic acid-induced vascular permeability test in mice. DSELE was devoid of ulcerogenic effect on the gastric mucosa of rats in acute and chronic tests. In acute toxicity studies, it was found to be safe up to 10.125 g/kg, p.o. in the rat. It was concluded that the D. sissoo leaf extract possessed significant anti-inflammatory activity (in acute, sub-acute and chronic models of inflammation) without any side effect on gastric mucosa. 相似文献
90.
O. P. Lal 《Journal of pest science》1977,50(2):28-29
Hibernation of the beetles, Altica caerulescens Baly and Macrima armata Baly in the Kula Valley, Himachal Pradesh
The flea beetle,Altica caerulescens Baly, is a pest of bringjal, tomato, spinach, strawberry and the weedsRumex sp. andImpatiens sp. in India. The beetle,Macrima armata Baly attacks the trees ofAlnus nitida and is also found as a minor pest of radish in Kulu Valley. Both of the beetles are found only in summer. Concerning the overwintering formerly it was supposed thatA. caerulescens hibernates in pupal stage. The autor describes for the first time about the overwintering of the two species in Kulu Valley based on a survey conducted in 1972 to 1975.
Altica caerulescens hibernates in adult stage under the bark of willow (Salix alba).Macrima armata adults were found in the winter in cracks of Kosh trees (Alnus nitida). 相似文献