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81.
The efficacy of two-way combinations of Trichoderma endochitinase (CHIT42), synthetic peptide ESF12 and resveratrol upon the control of growth of Botrytis cinerea and Penicillium digitatum were evaluated in vitro. CHIT42 had effective concentration for 50% growth inhibition (EC50) values of 1.5 and 0.5 µM against B. cinerea and P. digitatum, respectively. CHIT42 also caused swelling, hyperbranching and bursting of P. digitatum at concentrations as low as 0.003 µM. The EC50 values of ESF12 were 30.9 and 29.2 µM against B. cinerea and P. digitatum, respectively. Resveratrol had EC50 values of 178.6 and 343.2 µM against B. cinerea and P. digitatum, respectively. Combinations of CHIT42 + ESF12, CHIT42 + resveratrol and ESF12 + resveratrol showed additive activity (interaction ratios between 0.5 and 1.5) against B. cinerea and P. digitatum.  相似文献   
82.
Two new coumarins, 7-methoxy-5-prenylcoumarin (isocedrelopsin) (1) and 3',4'-dihydrobraylin (2), were isolated from the trunk bark of Cedrelopsis grevei, along with five known coumarins, microfolicoumarin (6,7-dimethoxy-5-prenylcoumarin, (3), obliquin (4), 8-methoxyobliquin (5), aesculetin (6), cedrelopsin (7) and scoparone (8).  相似文献   
83.
We sought to explain the declining distribution in the Balearic Islands of the endemic shrub Rhamnus ludovici-salvatoris R. Chodat, by comparing its photosynthetic response to drought with that of several widely distributed, competing Mediterranean species (R. alaternus L., Quercus ilex L., Pistacia lentiscus L., Q. humilis Mill. and P. terebinthus L.). All of the study species, except for the two Rhamnus species, avoided desiccation by rapidly adjusting their stomatal conductance at the onset of drought, and maintaining constant leaf relative water content. The two Rhamnus species showed desiccation-tolerant behavior; i.e., as drought progressed, their predawn leaf relative water content decreased simultaneously with stomatal closure. All four desiccation-avoiding species showed a significant positive correlation between leaf thermal dissipation (estimated by the fluorescence parameter NPQ (non-photochemical quenching)) and the de-epoxidation state of the xanthophyll cycle (DPS). The two Rhamnus species exhibited maximum DPS regardless of treatment, but only R. alaternus increased NPQ in response to drought. Rhamnus ludovici-salvatoris had a high ratio of photorespiration to photosynthesis and a low intrinsic water-use efficiency; traits that are likely to be unfavorable for plant productivity under arid conditions. It also had the lowest DPS and thermal dissipation among the six species. We conclude that the photosynthetic traits of R. ludovici-salvatoris account for its limited ability to compete with other species in the Mediterranean region.  相似文献   
84.
We evaluated the effects of supplementing betaine on growth performance, fat deposition and lipid metabolism status in broilers kept under chronic heat stress. Five hundred and forty chicks were randomly divided into six groups and the two normal temperature groups were held at normal ambient temperature and fed the basal diet (CONT) and basal diet plus 0.1% betaine, respectively. Heat stressed (HS) broilers were held at 32 ± 1°C from days 22 to 42 and fed the basal diet containing variable levels of betaine. Broilers were examined at days 28, 35 and 42 for body weight, feed consumption, fat deposition and serum lipids. The CONT and betaine‐supplemented groups showed higher (P < 0.01 or P < 0.05) feed consumption, body weight gain, and lower feed : gain ratio compared with the HS‐CONT group. Meanwhile, heat stress increased abdominal, intermuscular and subcutaneous fat deposition, whereas the supplemental betaine significantly decreased those compared with the HS‐CONT group. Additionally, betaine supplementation significantly decreased triglyceride, free fatty acids, low‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol compared with HS‐CONT. Chronic HS reduces broiler production performance. However, betaine can reverse these negative effects partially and thus improve carcass composition by changing lipid metabolism.  相似文献   
85.
86.
During 2005 to 2007, eggplant fields in 19 provinces from three different regions (western, southern and southeastern Anatolia regions) of Turkey were surveyed for Verticillium wilt. Sixty-seven isolates of Verticillium dahliae from wilted eggplants were collected and used for vegetative compatibility analysis using nitrate non-utilizing mutants and reference tester strains of vegetative compatibility groups (VCGs) 1A, 2A, 2B, 3, 4A and 4B. Among all isolates, 33 (12 from western, 15 from southern and six from southeastern Anatolia) were assigned to VCG2B, 23 (four from western, eight from southern and 11 from southeastern Anatolia) to VCG2A, six (four from southern, one from western, and one from southeastern Anatolia) to VCG4B and five (one from western, one from southern and three from southeastern Anatolia) to VCG1A, whereas VCG3 and VCG4A were not defined among isolates. In order to test if there is a correlation between VCG and pathogenicity in V. dahliae, pathogenicity of 30 isolates, representing the four multimember VCGs, were tested on Solanum melongena cvs. ‘Kemer’ and ‘Aydın Siyahı’ in an unheated greenhouse. All isolates were found to be pathogenic on both cultivars and there was no difference in susceptibility between the two cultivars. VCG4B isolates collectively led to higher vascular discoloration index (VDI) on both cultivars and higher disease severity index (DSI) on ‘Kemer’ compared with other VCGs. Similarly, VCG1A caused lower VDI on both cultivars and lower DSI on ‘Kemer’. Isolates within each of VCGs 1A, 2A and 4B caused similar VDI on both cultivars. Isolates of VCG2B were found to vary in their VDI values on both cultivars. To the best of our knowledge, the present study is the first report of natural infections of eggplant by VCG1A.  相似文献   
87.
Rice production in Pakistan is constraint by many factors pertaining to prevalent planting techniques. A research on the feasibility of new planting techniques (direct seeding on flat, transplanting on flat, direct seeding on ridges, transplanting on ridges and parachute planting) in transplanted and direct wet-seeded rice was undertaken at Dera Ismail Khan region of Pakistan’s North West Frontier Province during 2002 and 2003. Among the planting techniques, the best performance for the yield formation and economic evaluation was noted for transplanting on flat during both years. Chinese parachute planting technology also showed very promising results in most of the parameters. Direct seeding on ridges could not excel transplanting on flat and parachute planting during both cropping seasons. The findings concluded the feasibility of parachute planting technology along with traditional rice transplanting on flat over all other planting techniques being practiced in the area.  相似文献   
88.
In rice, the traditional system of transplanting gives the crop a 14 to 21-day growth advantage over the weeds [1]. The transplanting also enables rice to capture space earlier. This is because the young rice plants have leverage over germinating weeds due to shading and earlier establishment of root system. The immediate flooding after transplanting limits the establishment of many weeds [2]. Similarly, in direct seeded method, the use of high seed rates could reduce weed infestation to a lar…  相似文献   
89.
Two-year-grafting experiments within and between Gossypium barbadense and Gossypium hirsutum accessions were conducted to study the source, transfer, and alteration of gossypol and methylation of (+)-δ-cadinene synthase (CDN) genes along with whole chromosomes of A01, A04, A11, D01, D05, and D11, harbouring the cotton CDNs, using the whole genome bisulfite sequencing (WGBS) method. The results revealed that although a glandless line used in this study had a low level of gossypol in the seeds, it did not contain any pigment glands, indicating that expression pathways of gland and gossypol were under genetic control of different loci in cotton. Grafts with glandless rootstocks produced significant amounts of total gossypol in the seeds, clearly demonstrating that the source of gossypol biosynthesis was not specific to the root. Heterografts consisting of scion GN, a glandless line, and scion TM-1 grafted on Pima 3-79 rootstocks caused increased total seed gossypol levels whereas homograft TT had decreased total seed gossypol levels. Alteration of total gossypol levels was also associated with gland density, and DNA demethylation levels of (+)-δ-cadinene synthase genes.  相似文献   
90.
As the haemolymph supplier of the tachypleus amebocyte lysate industry in China, Chinese horseshoe crab (Tachypleus tridentatus) inevitably undergoes air‐exposure stress during transportation and haemolymph collection. In this study, the effects of air‐exposure stress and subsequent recovery process on the activities of phosphatases, antioxidant enzymes and haemocyanin concentration in Chinese horseshoe crab were investigated to understand its ability to resist air‐exposure stress. Results showed no significant effects on the total antioxidant capacity (T‐AOC), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and alkaline phosphatase (AKP) between the control and experimental groups during the air‐exposure stress period (0–4 hr), except acid phosphatase (ACP). During the subsequent recovery period in water, significant differences in plasma T‐AOC levels and SOD, CAT, AKP and ACP activities were observed between both groups. No significant effects of CAT activity, SOD activity, MDA content and T‐AOC level were noted between the two groups after 12 hr of recovery. However, the AKP and ACP activities of the experimental group were significantly lower than those of the control group. Results revealed that air exposure may affect the activities of most non‐specific immune enzymes in the plasma of Chinese horseshoe crab, showing a ‘delayed” interference effect. Nevertheless, tested antioxidant enzymes have a strong recovery ability and can generally recover to the control group level after 12 hr. Haemocyanin concentration was not affected by air‐exposure stress during the whole experiment. Hereby, Chinese horseshoe crab can strongly resist air‐exposure stress.  相似文献   
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