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61.
Deficiency of molybdenum (Mo) in acid soils causes poor growth of pulses. An experiment was, therefore, conducted in greenhouse to study the effect of Mo, phosphorus (P), and lime application on the dry matter yield and plant Mo concentration of lentil (Lens esculenta L.) in two Mo‐deficient acid alluvial soils. The experiment was conducted using a factorial design with three levels of lime (no lime, half, and full lime requirement), three levels of P (0, 25, and 50 mg kg‐1), and two levels of Mo (0 and 1.0 mg kg‐1). Plants were grown for 60 days and at harvest their dry matter yield and Mo concentration were recorded. The three treatments significantly increased dry matter yield, Mo concentration and Mo uptake, the increase being most pronounced with Mo application followed by lime and P. Increases due to applied Mo were greater in presence than in absence of added P; while the reverse was true with the liming treatments. Liming and P application at their lower levels also interacted positively for better Mo nutrition of plants. Results thus indicated that the severity of Mo deficiency in the lentil plants may be reduced by lime and P application in Mo‐deficient acid alluvial soils.  相似文献   
62.
Soil degradation in the semi-arid tropics (SAT) is mainly responsible for low crop and water productivity. In Madhya Pradesh and Rajasthan states in India, the soil analyses of farmers’ fields revealed widespread deficiencies of S (9–96%), B (17–100%) and Zn (22–97%) along with that of P (25–92%). Soil organic C was deficient in 7–84% fields indicating specifically N deficiencies and poor soil health in general. During on-farm evaluations in rainy seasons 2010 and 2011, the soil test based addition of deficient nutrient fertilizers as balanced nutrition (BN) increased crop yields by 6–40% (benefit to cost ratios of 0.81–4.28) through enhanced rainwater use efficiency. The integrated nutrient management (INM), however, decreased the use of chemical fertilizers in BN by up to 50% through on-farm produced vermicompost and recorded yields at par or more than BN with far better benefit to cost ratios (2.26–10.2). Soybean grain S and Zn contents improved with INM. Applied S, B, Zn and vermicompost showed residual benefits as increased crop yields for succeeding three seasons. Hence, results showed INM/BN was economically beneficial for producing more food, while leading to resilience building of SAT production systems.  相似文献   
63.
Journal of Plant Diseases and Protection - Spodoptera frugiperda (J E Smith) (fall armyworm) (Lepidoptera: Noctuidae), is a key pest of maize that has recently entered in India causing damage and...  相似文献   
64.
Commercial grade zinc (Zn) sulfate hepta hydrate (ZnSHH) is the most widely used source of Zn in India and several other countries for amelioration of Zn deficiency in crops. However, it releases water of hydration at temperature above 30°C and forms lumps on storage, which make it difficult to handle it and apply in fields. Therefore, conditioning of ZnSHH with ZnO and neem oil reduces the release of water of hydration and prevents lumps formation and can be well stored. Field experiments were conducted at the research farm of the Indian Agricultural Research Institute, New Delhi, India during rice growing seasons (July-November) of 2009 and 2010 to study the effect of conditioning ZnSHH with ZnO and neem oil on growth, productivity and Zn fortification of rice (Oryza sativa) grain and uptake by Basmati rice ‘Pusa 1121’. The experiment was conducted in a randomized block design with 3 replications comprised of 9 treatments of Zn fertilization. The present study shows that when conditioned with 2% ZnO and 4% neem oil ZnSHH improved yield attributes, grain and straw yields, Zn uptake and partial factor productivity (PFP), agronomic efficiency (AE), recovery efficiency (RE), and physiological efficiency (PE) of Zn in Basmati rice ‘Pusa 1121’. In general, ZnO was inferior to ZnSHH. Application of ZnSHH conditioned with 2% ZnO and 4% neem oil can be a better source of Zn for transplanted puddled Basmati rice on Zn deficient soils.  相似文献   
65.
As one of the most important and essential macronutrients next to nitrogen,phosphorus(P)is important for plant development,but it is the least mobile nutrient element in plant and soil.Globally,P is mined from geological sediments and added to agricultural soils so as to meet the critical requirements of crop plants for agronomic productivity.Phosphorus exists in soil in both organic and inorganic forms.The various inorganic forms of the element in soil are salts with calcium,iron,and aluminum,whereas the organic forms come from decaying vegetation and microbial residue.There is a huge diversity of plant microbiomes(epiphytic,endophytic,and rhizospheric)and soil microbiomes that have the capability to solubilize the insoluble P and make it available to plant.The main mechanism for the solubilization of inorganic P is by the production of organic acids,which lowers soil pH,or by the production of acid and alkaline phosphatases,which causes the mineralization of organic P.The P-solubilizing and-mobilizing microorganisms belong to all three domains,comprising archaea,bacteria,and eukarya.The strains belonging to the genera Arthrobacter,Bacillus,Burkholderia,Natrinema,Pseudomonas,Rhizobium,and Serratia have been reported as efficient and potential P solubilizers.The use of P solubilizers,alone or in combination with other plant growth-promoting microbes as an eco-friendly microbial consortium,could increase the P uptake of crops,increasing their yields for agricultural and environmental sustainability.  相似文献   
66.
The growing stock assessment of three different teak forest stands (Tuirial: 500 m asl, Sairang: 200 m asl and Phunchawng: 550 m asl) was done in 2006 in Mizoram, India. Five diameter classes were arbitrarily established for knowing the volume attribute data and population structure, viz. a (10-20 cm), b (20-30 cm), c (30-40 cm), d (40-50 cm), and e (50-60 cm). Results revealed that the density of the individuals among the studied stands varied from 280 stems/ha to 620 stems/ha. The average diameter of all the individuals ranged between 27.48 cm and 35.43 cm. Similarly, the average height was oscillated between 17.87 m and 22.24 m. The total basal area was recorded between 24.28 m2.ha-1 and 45.80 m2.ha"l. The maximum and minimum values of total growing stock under all the diameter classes were 669.01 m3.ha-1 and 284.7 m3.ha-1, respectively. The representation of population structure of different stands explained that the perpetuation of this species was ensured for a quite long time.  相似文献   
67.
With continuous outbreaks of stripe rust (Puccinia striiformis f. sp. tritici) epidemics and rapid breakdown of deployed resistance in bread wheat (Triticum aestivum L.) cultivars in North West Plains Zone (NWPZ) in India warrant knowledge and deployment of new and durable sources of resistance to stripe rust. Bread wheat cultivar PBW 343, until recently the most widely cultivated wheat variety in India, is now highly susceptible to stripe rust (score 9 on a 1–9 scale), whereas PBW 621 (score 5.05–5.65) and HD 2967 (score 5.40–6.20) show low levels of resistance. We conducted an experiment, spanning three crop seasons (2013–2014 to 2015–2016), in which parental lines, F1 and F2 populations, F3 and F4 families from two bread wheat crosses, PBW 621/PBW 343 and HD 2967/PBW 343 were generated and evaluated for stripe rust resistance against a virulent pathotype. While the F1 revealed partial dominance, the segregation pattern for stripe rust resistance in F2 and F3 showed transgressive segregation for resistance in both crosses. Chi-square analysis indicated that resistant segregants possessed two genes, one contributed by PBW 621 or HD 2967 (depending on the cross) and the other, unexpectedly but obviously, came from the most susceptible cultivar, PBW 343. Possible genetic mechanisms for this residual resistance and implications for breeding programs are discussed.  相似文献   
68.
In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits.  相似文献   
69.
ABSTRACT

Thermo-chemical conversion of crop residues to produce biochar is an emerging strategy in the context of sustainable phosphorous (P) use and residue management. An incubation study for 90 d was conducted to investigate the effects of rice-residue biochar (0, 10, 20 and 40 g kg?1) in combination with inorganic-P (KH2PO4) (0, 25 and 50 mg kg?1) on phosphorous availability in medium- and high-P status soils. Increasing biochar addition rates alone or in combination with inorganic-P resulted in a significant increase in P pools, i.e. plant available P or Olsen-P (from 8 to 132 mg kg?1 in medium-P and 15 to 160 mg kg?1 in high-P soils), microbial biomass P and various mineral-bound inorganic-P fractions in the order (Ca-P > organic-P > Al-P > loosely held/soluble-P > Fe-P > reductant soluble-P). Further, lower phosphatase activity (19–50%) with increasing rates of biochar addition in both soils elucidates the ability of biochar to act as a long-term source of available P in the experimental soils. The results demonstrate that rice-residue biochar can directly or indirectly enhance the status of available P in soils and hence can be used as a beneficial amendment to meet the crop P demand.  相似文献   
70.
A field experiment was conducted at the Livestock Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar, India during the wet season (June—October) of 1980 with the objectives of characterizing the seasonal changes in in vivo nitrate reductase activity (NRA) and N contents of upland rice cultivars grown under rainfed condition at low (0 kg N/ha) and optimum (80 kg N/ha) N fertility.
In vivo NRA increased initially up to panicle initiation stage (50 days after sowing) and declined, thereafter, until 90 days. Leaf NO3-N content paralleled with in vivo NRA throughout crop season. Total N content of leaves and stem declined with advance in crop age, whereas panicle N content increased with the crop development. Optimum N fertility (80 kg N/ha) always resulted in higher NRA, NO3 and total N contents of rice plants.  相似文献   
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