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51.
Ten tetraploid interspecific potato somatic hybrids developed earlier through protoplast fusion between the dihaploid Solanum tuberosum L. ‘C-13’ and the diploid wild species Solanum pinnatisectum Dun. were used in this study. Somatic hybrids and standard control cultivars were evaluated for adaptability, tuber traits, late blight resistance and keeping quality attributes (dormancy, sprouting, weight loss and appearance after 75 days of storage) during two successive winter crop seasons (short-days) in the sub-tropical plains of India, where nearly 90% of India’s potatoes are grown. Somatic hybrids showed medium to good plant vigour and late to very late plant maturity. Though none of the somatic hybrids produced equal or higher tuber yield than the control cultivars, except clone P7, all other somatic hybrids produced significantly higher marketable and total tuber yield after a 90-day growth than the parent C-13. Most of the somatic hybrids possessed higher tuber dry matter concentration, resistance to late blight and better keeping quality attributes than the control cultivars. Notably, the tubers of somatic hybrids showed a tendency for colour change from white to purple on exposure to sunlight. Breeding potential of somatic hybrids was further assessed by crossing them with commonly grown local potato cultivars for the development of backcross (BC1) progenies. In the hybridization programme, berries were formed while somatic hybrids were used either as male or female parents with common cultivars. Our results revealed that the use of bulk pollen of somatic hybrids not only resulted in higher pollination success but also helped to achieve higher numbers of true potato seeds (TPS) per berry. Despite the formation of berries, TPS was absent in 22 crosses using somatic hybrids as a female or male parent which may be due to ovule or embryo abortions. Segregating BC1 generations were evaluated under the same sub-tropical conditions for further exploitation in potato breeding. Based on our study, the somatic hybrids P4, P8 and P10 can be utilized for the introgression of important characters such as high tuber dry matter concontration, resistance to late blight and excellent keeping quality attributes into the cultivated potato via conventional breeding methods for cultivar development in the sub-tropical plains of India.  相似文献   
52.
Genetic Resources and Crop Evolution - An atypical morphotype of pea (Pisum sativum L.) was identified during the germplasm characterization programme at the Indian Council of Agricultural...  相似文献   
53.
In this study an attempt has been made to find a solution to the problem of disposal of distillery effluents through anaerobic followed by aerobic treatment. Accordingly, experimental studies were planned and carried out in two phases. The first phase experimentation was conducted to study the performance of Semicontinuous Fixed Film Anaerobic Reactors (SCFFAR) which simulate Downflow Stationary Fixed Film anaerobic reactors (DSFF) for partial treatment of distillery waste. Second phase experimentation included studies on degradation of anaerobically treated effluent employing semicontinuous aerobic reactors with sludge recycle. The results indicated that the distillery waste should be diluted to bring down the COD to about 50 000 mg L?1 before the same is treated by stationery fixed film anaerobic reactors and this dilution can be achieved by circulating the treated effluent. Further the reduction of COD beyond 9000 to 10 000 mg L?1 by anaerobic treatment appears to be uneconomical. Results of second phase of the study show that the aerobic degradation of anaerobically treated effluent can achieve significant COD reduction (approx. 67%). However, reduction of COD of final effluent below 500 mg L?1 appears to be very difficult. The settling characteristics of the sludge produced in aerobic study depended on the BSRT value and improved with increase in BSRT.  相似文献   
54.
The variability present in 20 plants of Capparis decidua (Forssk.) Edgew. (ker, family Capparaceae) from Fatehpur region of Rajasthan was investigated using different nutritional, biochemical and molecular parameters. Moisture content, crude protein, proline, total carbohydrate, starch, vitamin C, soluble sugar, crude fat, crude fiber, NDF, hemi cellulose, cellulose, lignin, ash, phosphorous, magnesium, iron, zinc, copper, sodium, potassium, cobalt, manganese, and calcium were estimated. Seventeen primers were used for random amplified polymorphic DNA (RAPD) analysis. A total 72 band positions were obtained using RAPD, of which 64 being polymorphic generated 87.6% polymorphism. Jaccard’s similarity coefficients ranged from 26 to 78.4%. The analysis of various biochemical and mineral constituents revealed that fruits are rich in carbohydrates (63.06 ± 4.20%) and protein (23.34 ± 4.38%) with high amount of potassium (3.23 ± 0.13%). The Manhattan dissimilarity coefficient obtained on the basis of biochemical and chemical analysis, ranged from 61 to 98%. The biochemical and RAPD based phylogenetic clustering were not correlated. Nevertheless, RAPD was found to be more efficient in estimating the diversity as compared to biochemical and chemical parameters.  相似文献   
55.
    
Globally, ravine landscapes are considered among the world's most degraded ecosystems. Restoring ravines is considered a high priority item in the conservation programmes, and tree establishment augmented with appropriate soil and water conservation measures is the most sought‐after restoration strategy. This study examined the impact of terracing and trenching on runoff, soil loss, and soil properties along with Sapota (Achras zapota) growth, fruit yield, biomass and carbon stock during 6 years (2010–2015) in a degraded ravine land of Western India. The four soil and water conservation strategies tested were (1) bench terracing + Sapota (Bt), (2) bench terracing + Sapota with crop cultivation (BtCr), (3) continuous slope + Sapota (Sl), and (4) continuous slope + Sapota with trenches (SlTr). All conservation techniques increased Sapota height (Bt: 54%; BtCr: 27%; SlTr: 35%) and basal diameter (Bt: 36%; BtCr: 18%; StCr: 22%) compared to Sl. Biomass and carbon stock of Sapota were in the order of Bt > SlTr > BtCr > Sl. During the droughtperiod, fruit yield was highest in Bt followed by BtCr, SlTr, and least in Sl. The treatment SlTr and Bt reduced runoff by 16–34% and soil loss by 15–25%, compared to Sl. The growth and biomass were strongly correlated with soil loss. The findings suggested that bench terracing is the best soil and water conservation measure for restoring highly degraded ravines of Western India. Under circumstances where terracing is not feasible, trenching could be a significant step along with Sapota plantation to restore these ravines.  相似文献   
56.
    
Estimation of the plant-available water capacity(PAWC) of soils at a regional scale helps in adopting better land use planning, developing suitable irrigation schedules for crops, and optimizing the use of scarce water resources. In the current study, 72 soil profiles were sampled from the Barossa region of South Australia to estimate pedo-transfer functions deduced from easily estimated soil properties. These functions were then used to estimate the fixed(10 and33 kPa) and dynamic pressure head(hfc) water contents at field capacity(FC) for minimum drainage flux(0.01 and 0.001 cm d-1), which serves as the upper boundary for plant-available water in soils. The estimated residual water content was corrected for subsoil constraints, especially the exchangeable sodium percentage(ESP). The results showed that the mean values of hfcin sand-dominated light and medium textured soils(i.e., sand, loamy sand, sandy loam, and loam) varied in a narrow range(15.8–18.2 kPa), whereas those in the clay-dominated heavy textured soils(i.e., clay loam) showed a wide range(11.3–49.3 kPa). There were large differences in PAWC for dynamic FC(PAWCf c) and fixed FC at 10 kPa(PAWC10), 33 kPa(PAWC33), and a mix of 10and 33 kPa(PAWC10,33) pressure heads depending on soil texture. Normally, the difference between PAWC at 10 kPa and hfc(?PAWC10) was positive,whereas that between 33 kPa and hfc(?PAWC33) was negative across all sites. Nevertheless, the estimation of PAWC assuming a fixed FC at 10 and 33 kPa pressures(i.e., PAWC10,33) for sandy, clay, and silty soils reduced the difference between fixed and dynamic pressure PAWCs to < 10% across the region.The estimation of PAWC was improved by incorporating the impact of subsoil constraints, such as high ESP, which was more pronounced for clay and silty soils. These findings demonstrate the inherent inconsistencies between static pressure and flux-based dynamic FC estimations in soils. Soil heterogeneity,intra-texture variability, subsoil constraints, and swell-shrink clays can have great impacts on the water retention capacity in response to dynamic and fixed pressure FC values.  相似文献   
57.
Drought resistance is becoming an indispensable character for rice improvement due to the dwindling global water resources. Genetic improvement for drought resistance is achieved through physiological dissection and genetic analysis of independent component traits associated with crop productivity under stress. A subset mapping population of 93 near flowering recombinant inbred lines with uniform phenology was constituted for genetic analysis of reproductive stage drought resistance. The population was phenotyped for 22 physio-morphological traits under two contrasting water regimes imposed at reproductive stage. Broad sense heritabilities of morphological traits were lower under stress than irrigated. Predominant association of plant height, panicle exsertion and harvest index with grain yield were observed under stress. The sustenance of panicle exsertion through maintaining growth during moisture stress was found as a significant trait associated with the grain yield through minimizing spikelet sterility. Selective genotyping was carried out with 23 polymorphic microsatellite markers of the established target genomic regions for drought resistance. The study validated the association of a QTL region on the long arm of chromosome 1 with plant height, panicle length, panicle exsertion, biological yield and stomatal conductance under stress. This region, flanked by markers RM246 and RM315, was known to possess the semi-dwarf gene, sd-1. Role of another major interval lying between RM256 and RM149 on chromosome 8 in defining the drought resistance could be established through identification of QTLs associated with leaf rolling, panicle exsertion, plant height, panicle length, senescence and biological yield under moisture stress condition. Few other QTLs were also identified.  相似文献   
58.
对喜马拉雅长叶松种子进行24小时GA3和H2O2浸泡预处理和15d的2-3℃低温预处理后,研究了在20℃,25℃和30℃萌发条件下,21个不同种源的喜马拉雅长叶松种子的萌发情况。结果表明,H2O2(1%v/v)和GA3(10mg/L)浸泡预处理,种子萌发率分别是82.39%和78.19%,而未经预处理的种子平均萌发率为70.79%。GA3和H2O2浸泡预处理分别使种子萌发时间缩短了8d和10d。在超过21天的20℃萌发条件下,湿冷处理提高了种子萌发率和缩短了萌发时间 而在25℃和30℃萌发条件下,总的萌发率未受到影响。喜马拉雅长叶松种子因缺少休眠而表现出很好的萌发,但是因为越来越多的造林项目需要大量的种子,播种预处理有利于提高种子萌发率和萌发速率,有助于满足种子需求。  相似文献   
59.
Helicoverpa armigera (Hübner) (Noctuidae: Lepidopetra) is a polyphagous pest of major crops grown in India. To prevent the damage caused by H. armigera farmers rely heavily on insecticides of diverse groups on a regular basis which is not a benign practice, environmentally and economically. To provide more efficient and accurate information on timely application of insecticides, this research was aimed to develop a forecast model to predict population dynamics of pod borer using Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Networks (ANN). The data used in this study were collected from the randomly installed sex pheromone traps at International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Hyderabad. Several ARIMA (p, d, q) (P, D, Q) and ANN models were developed using the historical trap catch data. ARIMA model (1,0,1), (1,0,2) with minimal BIC, RMSE, MAPE, MAE, and MASE values and higher R2 value (0.53) was selected as the best ARIMA fit model, and neural network (7-30-1) was found to be the best fit to predict the catches of male moths of pod borer from September 2021 to August 2023. A comparative analysis performed between the ARIMA and ANN, shows that the ANN based on feed forward neural networks is best suited for effective pest prediction. With the developed ARIMA model, it would be easier to predict H. armigera adult population dynamics round the year and timely intervention of control measures can be followed by appropriate decision-making schedule for insecticide application.  相似文献   
60.
Lincomycin 10 mg kg?1, IV in buffalo calves followed two-compartment open model with high distribution rate constant α (11.2?±?0.42 h?1) and K 12/K 21 ratio (4.40?±?0.10). Distribution half-life was 0.06?±?0.01 h and AUC was 41.6?±?1.73 μg mL?1 h. Large Vdarea (1.15?±?0.03 L kg?1) indicated good distribution of lincomycin in various body fluids and tissues. Peak plasma level of lincomycin (71.8?±?1.83 μg mL?1) was observed at 1 min as expected by IV route. The elimination half-life and MRT of lincomycin were short (3.30?±?0.08 and 4.32?±?0.11 h, respectively). Lincomycin 10 mg kg?1 IV at 12-h interval would be sufficient to maintain T?>?MIC above 60 % for bacteria with minimum inhibitory concentrations (MIC) values ≤1.6 μg mL?1. Favourable pharmacokinetic profile in buffalo calves and a convenient dosing interval suggest that lincomycin may be an appropriate antibacterial in buffalo species for gram-positive and anaerobic bacterial pathogens susceptible to lincomycin.  相似文献   
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