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51.
The sal forest is the only plainland forest in Bangladesh, and is of national economic and environmental importance. High population and ever increasing poverty has stimulated exploitation of the forest alarmingly and brought it near extinction. In facing this situation, the Bangladesh Forest Department implemented a participatory management approach, involving the householders living in and around the forests, for forest maintenance and protection. This study examines the effectiveness of practicing participatory forestry on the settlers’ livelihood in the encorached area of the sal forest. The settlers were given degraded and encroached forest land through the program. Two major social forestry models — namely agroforestry and woodlots — are included in the study. Participation in the resettlement increased household income, employment opportunities and financial and non-land assets. It was found that the participatory management regime could attain the sustainability of the forest and accelerate the standard of settlers’ livelihood, hence the program is an efficient management option towards sustainability of the forest resources. These findings suggest that there is a role for extending the approach to rehabilitate other degraded and encroached forest lands in Bangladesh.  相似文献   
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53.
Inter‐accession variation for salt tolerance of Panicum miliaceum (proso millet) was appraised using leaf proline content and activities of antioxidant enzymes as selection criteria. Eighteen accessions of proso millet were grown under control conditions and after 14 days subjected to saline (120 mm NaCl) stress for 4 weeks. Salt stress substantially decreased relative water content (RWC), while increased leaf free proline and malondialdehyde (MDA) and activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) of all accessions of proso millet. The difference among the accessions of P. miliaceum was significant in yield as well as in the activities of antioxidant enzymes analyses. On the basis of seed yield (expressed as per cent of control), of 18 accessions, three were categorised as salt‐tolerant (008211, 008214 and 008226), seven as moderately tolerant (008210, 008213, 008216, 008220, 008222, 008223 and 008242) and eight as salt‐sensitive (008208, 008215, 008217, 008218, 008221, 008225, 008230 and 008236). Of all P. miliaceum accessions, 008211, 008226, 008215 and 008218 were relatively higher in proline, 008214 and 008221 in MDA contents, 00812, 008225, 008236, 008222 and 008242 in SOD activity and 008218, 008220, 008211 and 008226 in POD and CAT enzyme activities. Thus, because of differential response of high or low seed yielded accessions in accumulation of proline and antioxidant enzyme activities, these variables were not found effective criteria for discriminating the P. miliaceum accessions for salt tolerance.  相似文献   
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Akram FATEMI 《土壤圈》2017,27(6):1105-1115
Knowledge on potassium ion(K~+) release from soils makes K fertilizer recommendation more efficient and profitable.Kinetics of K~+release under continuous fertilization of no fertilizer(CK), urea(N), triple superphosphate(P), and urea + triple superphosphate(NP) without K fertilizer was investigated in calcareous(chloritic and kaolinitic) soils on the Miandarband Plain in Kermanshah Province of Iran.The results showed that the kinetics of K~+release included an initial reaction and a slow reaction.The phosphateand NH_4~+-induced K~+release followed the same rate process during the rapid(2–192 h) and slow release periods(192–1 090 h).There were no significant differences in the cumulative K~+released from the chloritic and kaolinitic soils among all the treatments.The cumulative K~+released was positively correlated with P adsorption capacity for the chloritic(r = 0.461, P 0.05) and kaolinitic soils(r = 0.625, P 0.01), and negatively correlated with K fixation potential for the chloritic(r = 0.720, P 0.01) and kaolinitic soils(r =-0.513, P 0.01).There was a significant(P 0.001) interactive effect of K fixation potential × P adsorption capacity on the cumulative K~+released for both soil groups.The initial release rate(IRR) index(a·b, where a and b are the rate coefficients of the power function equation) for the chloritic soils was significantly(P 0.05) higher under applications of P and NP than N and CK.The IRR index values among different fertilization treatments were in the order of NP = P N = CK for the chloritic soils, and N =P NP CK for the kaolinitic soils.This study showed that K fixation potential and P adsorption capacities controlled K~+release from soils.This information will be helpful for precise fertilizer recommendations for the studied soils.  相似文献   
55.
In the present study, 48 crossbred does (Nubian × Baladi) were used to investigate physiological (mucus and hormonal) traits as affected by gestation pattern (pre‐, full‐ and post‐term parturitions). The incidence of full‐term (does with a gestation length of 146–152 days) was the highest (54.5%), followed by pre‐term (does with a gestation length of 140–145 days; 36.9%) and post‐term (does with a gestation length of 153 days; 8.9%), respectively. Prediction of gestation pattern by using some body measurements was also studied. Cervical mucus samples were collected during estrus to determine spinnbarkeit (i.e. strength, viscosity or stretchability) and pH values of the mucus. Mucus was also collected pre‐parturition daily from day 140 of gestation until delivery, to evaluate the ferning arborization. Blood samples were collected on the day before mating (0 time), 1 (at mating), 30, 60, 90 and 145 days after mating. The results showed that spinnbarkeit and pH in cervical mucus at estrus, serum estradiol‐17α (E2) at day 5 before delivery, and progesterone (P4) levels differed insignificantly according to gestation pattern. The fern degree between day 140 of gestation and day of delivery was the highest in pre‐term does, while it was the lowest in post‐ and full‐term does. The gestation length was the highest in post‐term does (157.5 days), and the lowest in pre‐term does (141.5 days). During winter, the incidence of pre‐term deliveries was the highest (54.5%), but in spring, full‐term deliveries were the most common (58.3%). Most of the traits studied were insignificantly affected by season of birth. Post‐term delivery can be estimated by doe weight and wither height, while full‐term delivery can be anticipated using by hip height and abdomen girth. Pre‐term does can be detected by cervical mucus fern between day 140 of gestation and day of delivery. Post‐term does can be defined by doe weight and wither height, while full‐term deliveries can be defined by hip height and abdomen girth, during pregnancy.  相似文献   
56.
Milk yield (MY), composition, and fatty acid profiles of purebred Holstein (HO) cows, Brown Swiss (BS), and their F1 crossbreds (HS) were compared under subtropical climate in Egypt. Pure HO had significantly greater 305-MY, total-MY, and daily-MY (p?<?0.05) than pure BS and crossbred HS. Furthermore, HO and HS had significantly higher peak-MY (44.2 and 43.3 kg, respectively) than BS (36.1 kg). In comparison with HO, BS had significantly higher milk fat, protein, total solids, and solid-not-fat % (p?<?0.05); however, no significant differences were observed between BS and HS for milk fat %. The milk fat of BS had higher concentrations of saturated (C17:0 and C18:0) fatty acids (FA) than that of the HO and HS (p?=?0.001 and 0.008, respectively). Content of C4:0, C6:0, C8:0, C12:0, and C15.0 FA did not differ between genotypes. Milk from HO and BS had significantly higher concentrations of unsaturated (C20:1 and C20:5) FA than that from HS (p?<?0.05). C14:1 (myristoleic), C16:1 (palmitoleic), and C18:2 (linoleic) FA contents were similar for all genotypes. In conclusion, BS surpassed HO for all milk composition traits and some FA components; however, HS had comparable milk fat percentage with BS. There appears to be an opportunity to modify the concentration of certain FA by breeding.  相似文献   
57.
Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak (Tectona grandis L.). Higher number of shoots (6.17) per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2–4 cm long softwood shoots were excised and treated with either indole-3-butyric acid (IBA) or α-naphthyl acetic acid (NAA) at 0, 1000, 2000 or 3000 μmol·L–1 each or with combinations (1000 + 1000, 2000 + 2000 or 3000 + 3000 μmol·L–1) and then placed in flat trays containing autoclaved sand at 25 ± 2ºC in 16 h photoperiod at 35 µmol·m–2·s–1. After 28 days, softwood cuttings treated with IBA + NAA (3000 + 3000 μmol·L–1) had highest rooting percentage (89.3%) with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% (w/v) ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone (PVP) for 24 h to remove phenolic compounds before surface disinfestation. Glutamine (Gl) and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol·L–1 6-benzylaminopurine (BAP) + 5 μmol·L–1 NAA. Using shoot apices, highest (42.80) number of multiple shoots with 54.33 mm shoot length were obtained on MS + BAP (8.8 μmol·L–1) + IBA (2 μmol·L–1) after 45 days. Shoots were successfully rooted and acclimatized to greenhouse  相似文献   
58.
Yellow mosaic disease (YMD) is the major constraint of mungbean for realizing high productivity worldwide. Moreover, management of disease using YMD‐resistant genotypes is the simplest approach. Therefore, based on a preliminary screening of 220 genotypes during the year 2010 and 2011 at 17 locations, a set of 25 genotypes was further selected to evaluate at six locations over 2 years for identification of more stable resistant genotypes. The genotype and genotype × environment (GGE) analysis indicated that the genotypes and environment effects were significant (P < 0.001) for YMD incidence. Interestingly, the GGE biplot analysis successfully accounted for 74.71 per cent of the total variation with three genotypes (ML 818, ML 1349 and IPM 02‐14) showing high degree of resistance and stability over the locations. Notably, a strong positive association was observed between disease reaction and temperature, relative humidity and rainfall. As crop is grown in diverse growing environments, aforementioned genotypes can be used as stable/durable sources for future breeding programme to develop YMD‐resistant cultivars.  相似文献   
59.
Bivalves are known for their high nutritional value and are considered a healthy food for human consumption. The effect of different cooking methods (steaming, boiling, grilling, and frying) on proximate and fatty acid composition of Arca noae (Bivalvia: Linnaeus 1758) were determined. The comparison of raw and cooked Ark shell showed that the cooking had considerable effects on the nutritional quality of this species. Significant changes in moisture (%), protein (mg/g of flesh), total lipid (mg/g of flesh), and fatty acid composition (mg/g dry weight) were observed after cooking as compared to fresh Ark shell (p < 0.05). However, the analysis of malondialdehyde (MDA) and peroxide value (PV) showed that all cooking treatments led to lipid oxidation. Steaming, boiling, and grilling were found to be a suitable and healthier cooking processes for A. noae, since they conserve the amount of n-3 PUFA better as compared to frying.  相似文献   
60.
Cultivar mixtures can stabilize yield and reduce pathogen spread in plant populations. A field experiment was performed to determine (a) whether a large difference between the cultivars in the mixture (e.g., plant height or earliness) would have an impact on mixture performance, and (b) whether such differences would modify the classical rules for mixture design. Mixtures were constituted from wheat cultivars with diversity for many traits, including plant height, flowering date, disease resistance, and yield potential. The field experiment was conducted over 3 years, testing each year 72–90 mixtures of two, four, or eight cultivars, and their corresponding pure stands. Disease severity and yield of cultivar mixtures were strongly related to the mean values of the component cultivars in pure stands. Despite the considerable diversity of the mixtures tested, the classic rules (e.g., proportion of susceptible cultivars) already tested in mixtures with similar height and earliness were effective for decreasing disease severity. Agronomic heterogeneity for traits such as plant height, yield potential, or earliness of the cultivars in mixtures did not have a negative impact on disease severity and yield relative to pure stands. Increasing the number of cultivars in the mixture from two to eight had no impact on the mean disease severity and yield of the mixtures, but reduced the variability of disease severity and yield in the mixture relative to pure stands. These results suggest that it may be possible to increase within-field wheat diversity by combining more contrasting cultivars in mixtures than was previously thought.  相似文献   
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