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61.
《Journal of Crop Improvement》2013,27(2):165-195
Summary Micronutrient fertilizer sources are mostly sulfates for Zn, Cu, and Mn, but chelates are the usual Fe source, and borax and sodium molybdate are used for B and Mo, respectively. Soil pH is the soil property that most influences micronutrient availability, and for all but Mo, the higher the soil pH, the lower is the plant availability. For Mo, liming can actually prevent deficiencies. Other soil properties that are important in bioavailability are organic matter content, especially for Cu, oxidation/reduction conditions, especially for Fe and Mn, soil texture, Fe and Al oxide content and soil moisture conditions. 相似文献
62.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2153-2164
Abstract The chemical diagnosis of nutritional status of Bael (Aegle marmelos Correa) tree by leaf analysis was done to study the effect of leaf age and leaf position on foliar nutrient composition of Bael. The results showed that leaf age has significant influence on leaf mineral content, whereas the position of leaf on shoot did not have any significant effect. Interactions between leaf age and position were found to be significant for nitrogen, boron and iron content. In general, stability in level of nitrogen (N), phosphorus (P), and potassium (K) contents was observed in November–December (6‐ to 7‐month‐old leaves) and calcium (Ca) and magnesium (Mg) showed their stability in 2‐to 3‐month‐old leaves (July–August). The contents of boron (B), manganese (Mn), copper (Cu), and zinc (Zn) were found stabilized in September–October (3‐ to 4‐month‐old leaves), indicating their suitability for sampling in Bael. 相似文献
63.
《Communications in Soil Science and Plant Analysis》2012,43(14):1675-1691
Greenhouse experiments in a completely randomized block design were conducted to assess the effect of soil salinity on emergence, growth, water status, proline content, and mineral accumulation of seedlings of Tamarindus indica Linn. (Caesalpiniaceae). Sodium chloride (NaCl) was added to the soil, and the salinity was maintained at 0.2, 3.9, 6.2, 8.1, 10.0, 11.9, and 13.9 dS m?1. Salinity lowered water content and water potential of tissues, which resulted in an internal water deficit to plants. Consequently, seedling growth significantly decreased and proline content in tissues increased as salinity increased. There were no effective mechanisms to control net uptake of sodium (Na+) and its transport to shoot. Potassium (K) and calcium (Ca) contents in tissues significantly decreased, while nitrogen (N) content significantly increased as salinity increased. Changes in tissues and whole-plant accumulation patterns of other nutrients, as well as possible mechanisms for avoidance of Na+ toxicity in this species in response to salinity, are discussed. 相似文献
64.
《Communications in Soil Science and Plant Analysis》2012,43(9):1050-1070
In the present study, gyttja and its humic–fulvic concentrate were applied to soil either alone or in combination with a chemical fertilizer in a 2-year replicated field experiment with continuous bread wheat cropping during two seasons between 2005 and 2007 in Cukurova, Adana, Turkey. The changes in soil organic matter (SOM) characteristics and available micronutrient status were monitored by soil samplings performed immediately after the harvest in the 2005 and 2006 cropping seasons. The results showed that single and combined applications of humic substances with different types and doses showed different inclinations on selected soil characteristics in consecutive cropping seasons. The levels of SOM, available phosphorus, and grain yield significantly increased under different humic treatments in the first year of the experiment. However, humic substances added to the soil did not affect selected soil parameters and macro- and micronutrient status in the second year of the experiment. 相似文献
65.
《Communications in Soil Science and Plant Analysis》2012,43(1):94-108
Zinc (Zn) deficiency is very common in annual crops grown on Brazilian Oxisols. A greenhouse experiment was conducted to evaluate Zn-use efficiency of 20 upland rice genotypes. The Zn levels used were 0 mg kg?1 (natural level of the soil) and 20 mg kg?1 of soil applied with zinc sulfate (ZnSO4). Zinc × genotype interactions were significant for grain yield, panicle number, panicle length, root dry weight, and specific root length, indicating different responses of genotypes with the variation of Zn levels and that selection for Zn-use efficiency is necessary at low as well as at high Zn rates. Based on Zn-use efficiency index, 11 genotypes were classified as efficient and nine were classified as moderately efficient. The most Zn-efficient genotypes were BRA 01596, BRA 042156, BRA 052053, BRA Primavera, and BRA 01506. The most inefficient genotypes in Zn-use efficiency were BRA 042094, BRA 052045, BRA 052034, and BRA 052023. Grain yield and most of the yield attributing characteristics have significant Zn × genotype interactions, which indicate that genotypes respond differently under different Zn levels. Thus, genotype selection is an important strategy for upland rice production in Brazilian Oxisols. 相似文献
66.
《Communications in Soil Science and Plant Analysis》2012,43(14):1736-1750
Substrates have been increasingly used in recent years for carnation crops. Burnt rice husk (BRH) is widely available and used as a substrate in Colombia. The present work aims to compare the effects of two aqueous extraction methods on the chemical contents. Saturated and 1:1 (v/v) extractions were performed in three replications. Ionic forms of the macronutrients (NO3?, NH4+, PO4H2?, K+, Ca2+, Mg2+, and SO42?, in meq L?1), micronutrients (Fe, Mn, Zn, Cu, and B, in mg L?1), Cl?, CO3 H? in meq L?1, electrical conductivity in dS m?1, and pH were analyzed. Except for NH4+, Cl?, and B the determination coefficient R2 was greater than 95 percent. Average values and standard errors of data have been used to define suitable intervals for 1:1 extractions. Proposed intervals for 1:1 extracts are consistent with the saturated extract and therefore are a good tool to optimize the management of fertigation in those crops. 相似文献
67.
《Communications in Soil Science and Plant Analysis》2012,43(13):1576-1593
In many parts of the world, boron (B) levels are insufficient for potential production. Boron deficiency is also widespread in the Anatolia region of Turkey. Boron deficiency could impact production and quality of tomatoes (Lycopersicon esculentum L.), pepper (Capsicum annum L.), and cucumber (Cucumis sativus L.). A two-year greenhouse experiment was conducted to study yield and quality response of three vegetables to B addition (0, 1, 2, 3, and 4 kg B ha?1). The optimum economic B rates (OEBR) were 2.3, 2.6, 2.4 kg B ha?1, resulting in soil B concentrations of 0.33, 0.34 and 0.42 mg kg?1. Independent of plant species, B application decreased tissue nitrogen (N), calcium (Ca), and magnesium (Mg) but increased tissue phosphorus (P), potassium (K), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentrations. We conclude that a B addition of 2.5 kg ha?1 is sufficient to elevate soil B levels to nondeficient levels. Similar studies with different soils and initial soil-test B levels are needed to conclude if these critical soil test values and OEBR can be applied across the region. 相似文献
68.
Jagreeti Gupta R. K. Dubey Nirmaljit Kaur O. P. Choudhary 《Journal of plant nutrition》2018,41(13):1724-1733
The present investigation was conducted at Punjab Agricultural University, Ludhiana, Punjab, India to screen four ornamental tree species ideal for salt-affected environment. Screening was done on the basis of nutrient accumulation in leaves and roots. The 1-year-old tree seedlings growing in 10″ pots were subjected to five levels of sodium chloride salinity stress (control, 30, 40, 50, and 60 mM). Experimental design utilized was factorial completely randomized block with three replicates in each treatment. In addition, the sodium (Na+)/ potassium (K+) ratio in leaves and roots of all ornamental tree species was determined. Based upon nutrients content and Na+/K+, the order of salinity tolerance observed in the study was Casuarina equisetifolia > Acacia auriculiformis > Callistemon lanceolatus > Putranjiva roxburghii. 相似文献
69.
Rilner Alves Flores Talles Victor Silva Virgínia Damin Renata de Castro Marques Carvalho Débora Regina Marques Pereira Jonas Pereira de Souza Junior 《Communications in Soil Science and Plant Analysis》2018,49(6):725-734
Aspects related to micronutrients management are still poorly studied and need to be clarified to guarantee sustainable production. In this way, the study aimed to evaluate boron (B) fertilization effects on nutrition and production of common beans. The parameters measured were relative chlorophyll index, dry mass, boron transport, utilization and absorption efficiencies, B content, and B accumulation in plant tissues. The study showed that the dry mass production was negatively affected by B application, with linear dry mass decrease following the increase of B doses. Accordingly, it was found that the common bean cultivar Esplendor presented high absorption capacity of boron, and can reach 175 mg kg?1. However, the high absorption caused phytotoxicity and reduced dry matter production by up to 30%, reflecting the efficiency of boron use by the plant, which was reduced in up to 75%. 相似文献
70.
Mehrab Yadegari 《Communications in Soil Science and Plant Analysis》2017,48(3):307-315
To evaluate the effects of irrigation period and iron (Fe), zinc (Zn) foliar application on agronomic characters in Borago officinalis, Calendula officinalis, Thymus vulgaris and Alyssum desertorum, investigations were performed in a complete randomized block design with three replications in 2014 and 2015. The factors applied were (a) Fe foliar application (0, 200, 400, 600 ppm), (b) Zn foliar application (0, 200, 400, 600 ppm) and (c) irrigation periods (3, 6, 9 days). Results showed that Fe and Zn had a significant effect on many factors including shoot dry matter, height, flower production (marigold, borage and thyme) and seed (alyssum). Interaction of 400 ppm of Zn and Fe with irrigation period every 3 days was the best and produced the best amounts in most of the measured characters. The lowest of the measured characters was 600 ppm of Fe and Zn by irrigation period of 9 days. Results showed that Zn micronutrient was more effective than Fe. 相似文献