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81.
Effects of irrigation, mulch and nitrogen on yield and composition of Japanese mini ( Mentha arvensis L. subsp. haplocalyx Briq. var piperascens) oil were studied using a replicated experiment. Two harvests were obtained 120 davs atter planting and 75 davs after the first harvest. Significantly higher drv matter and essential oil yields were obtained with frequent irrigations (50 mm Cumulative Pan Evaporation), application of mulch and Nitrogen. The economic optimum rate of N was 215 Kg ha-1. The essential oil from the first harvest was richer in menthol (78.8%) than the oil obtained from second harvest (75.2%). Soil moisture extraction was maximum between 15 and 30 cm soil depths. Consumptive use, water use efficiency and moisture use rate-were maximum under higher irrigation levels and mulch application which reflect that more availability of moisture in soil profile with frequent irrigations and application of mulch.  相似文献   
82.
The ultrastructure of interactions of pea downy mildew ( Peronospora viciae ) on the leaves and petioles of two cultivars of pea, Superb and Maro, was examined. Tissue fixed at the time of sporulation (10 days after inoculation) revealed that many of the intercellular hyphae in Maro were showing evidence of partial or complete autolysis. The penetration matrices were enclosed in a thicker layer of callose-like material than in Superb, and many of the haustoria had collapsed, distorted profiles. Analysis of organelles lying close to the extra haustorial membrane revealed fewer associations with endoplasmic reticulum in Superb.  相似文献   
83.
A pot culture experiment was conducted on a soil marginally deficient in diethylenetriaminepentaacetic acid (DTPA) extractable zinc under the glass house conditions of Lucknow University to observe the effect of zinc (Zn) alone and a combination of Zn with boron (B) on the growth and reproductive yield of maize. Studies conducted on plant height, dry matter and reproductive yield and tissue element concentration in leaves and grains at harvest showed significant increase over the control. Activities of enzymes, carbonic anhydrase and superoxide dismutase determined in comparable middle leaves increased with the application of both the nutrients. Pollen diameter, pollen-producing capacity of mature anthers, grain protein, starch and phytate content were also positively correlated with the addition of nutrients. The residual value of available Zn and B in soil left after the removal of crop was found good enough to sustain the next crop.  相似文献   
84.
An experiment was initiated in 2008 to evaluate the impact of irrigation regimes on germination and growth patterns of seedlings of Prosopis cineraria in the arid areas of Thar, India. Seeds collected from dried pods of P. cineraria were sown in polybags placed in nursery beds. Different irrigation regimes were provided to different beds and data regarding germination and growth were recorded to study natural regeneration. The study revealed that irrigation regimes significantly affected the germination and growth of P. cineraria under nursery conditions. The germination rate declined as the irrigation regime shifted from a daily to a fortnightly basis. Height of the seedlings also declined with a decrease in the intensity of irrigation. Thus, it can be concluded that germination and growth of seedlings of P. cineraria under nursery conditions can be enhanced by providing irrigation at regular intervals.  相似文献   
85.
The potential of potato flour as a humectant (anti-staling agent) was investigated. The experiment utilised eight variants of potato flour, prepared from processing cultivar K. Chipsona-1 and table cultivar K. Laukar, in muffins as a bakery product. On the basis of higher values of water retention and water absorption, and comparatively lower values of setback and flavour intensity, grilled (180 W for 25 min) potato flour from cultivar K. Laukar (GPF-T) was selected for muffin preparation. For optimization, muffins were prepared with GPF-T at 1, 3, 5 and 7% (w/w) level in the formulation. The storage study was conducted for 8 days at 25?±?2 °C and 55?±?5% RH. It was concluded from the product characterisation, sensory evaluation and storage study that 3% GPF-T can be used as a low-cost alternative to commercially available humectants for muffin preparation. Research findings may be adopted by small-scale industry entrepreneurs to delay the staling of muffins two-fold without adversely affecting the sensory scores.  相似文献   
86.
Translocation of 2,4-D, asulam and amitrole in water hyacinth   总被引:1,自引:0,他引:1  
In glasshouse experiments foliar application or 14C-labelled herbicides to water hyacinth plants at the 4-leaf stage indicated that amilroie transport from the treated leaf blade was faster and greater than 2.4-D. but a little less than asulam. From the treated leaf 14·2, 25·9. 39·7. 44·5 and 51·8% of the recovered 14CNamitrole was translocated at intervals of 6 h. and 1. 3. 6 and 12 day., respectively. Both xylem and phloem transport of asulam and amitrole was evident, whereas 2.4-D moved only from ‘source to sink’. Movement of the herbicides from the mother to the connected daughter plant or vice versa was dependent upon the size of the latter. Maximum transport of these herbicides in either direction took place at the 2-leaf stage of daughter plants. With any increase or decrease in the number of leaves on daughter plants, the transport of herbicides was reduced. As an exception, daughter plant to mother plant movement of amilroie was maximum at the 1-leaf stage. After extraction, fractionation and TLC separation of foliage applied 14C-2.4-D 76–4 and 72·1% of the radioactivity was detected in the chloroform phase of the leaf extract at 3 and 6 day intervals, respectively. In another pot culture experiment, it was observed that after spraying the mother plants with 2.4-D-amine at 0–75 kg/ha the connected daughter plants at 1 to 4-leaf stages werckilled if the culture solution was contaminated while spraying, or by dying leaves. When contamination was totally avoided, the connected but unsprayed daughter plants at 3 to 4-feaf stages survived.  相似文献   
87.
A new disease of Cymbopogon winterianus , characterized by symptoms of sheath rot and leaf blight, has been observed in the Tarai region of Uttar Pradesh (IN). The pathogen has been isolated and identified as Rhizoctonia solani.  相似文献   
88.
Wheat (cv. WH-147) and five biotypes of Phalaris minor Retz. (KR-1, H-4, K-2, H-2 and J-1) were treated with isoproturon in controlled environmental conditions to assess their level of resistance. Resistance of P. minor to isoproturon was found in the order of KR-1 > H-4 > K-2 > H-2 = J-1. Compared with the susceptible (S) biotype (H-2), the resistant (R) biotypes (KR-1. H-4 and K-2) of P. minor required 13.0, 4.5 and 2.7 times higher doses of isoproturon for a 50% reduction in growth (GR50) and 2.4 times that of the S biotype (H-2) by wheat. The corresponding figures for KR-1, H-4, K-2 biotypes and wheat were 18, 4.1, 2.4 and 4.6 times based on dry weight reduction. The effect of isoproturon on photosynthesis was studied in vitro using five biotypes of P. minor and in viro with wheat. KR-1 (R) and H-2 (S) biotypes of P. minor. Under in vitro treatment conditions isoproturon inhibited the photosynthesis of all five P. minor biotypes, whereas in vivo the recovery was greater in the R biotype than in the wheat and the S biotype. Effects on chlorophyll fluorescence were also measured in wheat and the KR-1 (R) and H-2 (S) biotypes of P. minor. A 4-h treatment of excised leaves incubaled in isoproluron solution (0.025 and 0.05 mm concentration) resulted in a decreased fluorescence coefficient (Fv Fm ratio in which Fv= variable fluorescence (Fm - Fo): Fm= the maximum fluorescence and Fo= initial fiuorescence) in wheat (Triticum aestivum L.) and both biotypes of P. Minor. The recovery was, however, greater in the R biotype than in wheat and it was completely recovered within 24 h. No recovery was recorded in the case of the S biotype of P. minor and a greater recovery time was required for wheat than the R biotype. The higher dose required for growth inhibition in the R biotype and rapid recovery of oxygen evolution and fluorescence coeflicient under in viro conditions together with the absence of selectivity in vitro suggests that the target site was unaffected. It can be conjectured that resistance to isoproturon is most probably because of enhanced metabolism or sequestration of isoproturon, resulting in decreased target site delivery.  相似文献   
89.
Celery yellow net w s described by Hollings (1964) s severe dise se of celery (Apium graveolens L. var. duke (Miller) DC.) that could be transmitted by grafting nd occasionally by mechanical inocul tion with leaf extracts. Pemberton & Frost (1986) observed similar symptoms in celery crops. but were unable to isolate the causal agent.
During recent attempts to isolate the causal gent of celery yellow-spot, another disease previously reported by Hollings (1964) and Pemberton & Frost (1986), we found that two of our samples from crop in Cheshire contained different virus. As well as yellow spots, these two plants also had yellow-net symptoms on the older leaves, and one of the plants was stunted with some distortion of the young leaflets. The two virus isolates appeared identical from extensive testing on range of herbaceous indicator plants, so one of them, CV506, w s selected for further study  相似文献   
90.
The reactions of parents and F1 and F2 generations of crosses of chickpea cultivars K-850 with C-104 and JG-62 and F3 progenies of K-850 × C-104 to race 1 of Fusarium oxysporum f.sp. ciceri were studied. The results indicate that K-850 carries a recessive allele for resistance at a locus different from and independent of that carried by C-104 and recessive alleles at both loci together confer complete resistance. The possible contribution of this recessive gene to late wilting in K-850 is discussed. These observations have important implications in breeding for resistance to wilt in chickpea.  相似文献   
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