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71.
K. N. Rai  R. P. Thakur 《Euphytica》1995,83(3):225-231
Summary High ergot (Claviceps fusiformis Loveless) susceptibility of pearl millet (Pennisetum glaucum (L.) R. Br.) hybrids has often been associated with the A1 cytoplasm of male-sterile lines (A-lines). To understand the underlying basis of this association and to examine the prospects of breeding ergot-resistant hybrids, we evaluated 56 hybrids and their 15 parental lines for ergot reaction and selfed seedset for 2 years in disease nurseries at ICRISAT Asia Center. Hybrids were made by crossing seven pollen parents (2 susceptible and 5 resistant) onto two resistant and two susceptible A-lines, and their four corresponding maintainer lines (B-lines). A-lines had no selfed seedset while B-lines had 32–75% selfed seedset. Hybrids of A-lines had significantly less selfed seedset than the hybrids of the corresponding B-lines. The reduced seedset of A-lines and their hybrids, however, was not always accompanied by significantly higher ergot susceptibility. Highly resistant hybrids were obtained where both A-lines and pollen parents were highly resistant, regardless of male fertility levels of the hybrids. Thus, although the A1 cytoplasm, by its reduction of male fertility, had a large and significant effect in increasing ergot severity of hybrids, the contribution of nuclear genetic factors of female parents was about 1.8 times larger than that of the cytoplasm.Submitted as JA No. 1776 by the International Crops Research Institute for the Semi Arid Tropies.  相似文献   
72.
73.
The leaf nutrient status of 3 mango cultivars, determined in fruiting and non-fruiting terminals after fruit harvest (June 1976) from 20 orchards, were compared. N, P and Ca contents were significantly higher in ‘Dashehari’ than in ‘Chausa’ and ‘Lucknow Safeda’. The reverse was true for K, S and Zn contents. Mg and Mn contents were more or less at par in all the 3 cultivars. Leaves collected from non-fruiting terminals contained significantly higher amounts of N and P in all the 3 cultivars, but K, Ca, S and Zn only in 2 cultivars, as compared to those from fruiting terminals. Mn and Fe contents in both kinds of terminals were more or less at par in all the 3 cultivars.  相似文献   
74.
75.
The present study was conducted to evaluate the effect of commercial exogenous fibrolytic enzyme (EFE) mixture added at 1.5 and 3.0 g (cellulase 4,000 μM glucose/g/h + xylanase 7,990 μM xylose/g/min; 50:50 w/w) per kilogram of dry matter (DM) of feed on nutrient digestibility, milk production, milk composition, and some blood constituents in lactating Murrah buffaloes. Eighteen buffaloes were allotted to three dietary treatments, on the basis of milk yield (8.48, 8.52, and 8.53 kg/day) and days in lactation (68.5, 80.33, and 82.00) for 90 days. The buffaloes were fed a total mixed ration (TMR) comprising of 45% chaffed wheat straw, 15% chopped green maize, and 40% concentrate on DM basis (control group), the same TMR plus EFE at 1.5 g/kg DM (T-1 group) and the same TMR plus EFE at 3.0 g/kg DM (T-2 group) supplemented through the concentrate mixture. There was no effect of fortifying EFE mixture on DM intake and crude protein intake (grams per day) whereas total digestible nutrients intake (kilogram per day) was higher by (P < 0.05) 12.53% in T-1 group over that of control, and there was no significant difference between T-2 and control groups. The average daily milk yield and 4% fat-corrected milk (FCM) yield was higher (P < 0.05) by 12.99% and 15.17% in T-1 group as over that of control, and there was no difference between T-2 and control groups. There was no (P > 0.05) difference in blood glucose and blood urea nitrogen concentration in different experimental groups. It is concluded that supplementation of cellulase and xylanase mixture at 1.5 g/kg of DM of TMR containing wheat straw (45%), green maize (15%), and concentrate (40%) on DM basis significantly increased (P < 0.05) the average daily milk yield and FCM yield in Murrah buffaloes due to improved dietary fiber digestion.  相似文献   
76.
Paddy and Water Environment - System of rice intensification (SRI) together with appropriate nutrient management holds promise in increasing rice productivity with micronutrient enriched grains....  相似文献   
77.
R. Thakur  R. P. Roy 《Euphytica》1975,24(2):511-516
Summary It has been found that long palea, an easily identifiable trait, is attributable to two duplicate recessive genes designated lp 1 and lp 2. A new character, uneven kernel has been described, the espression of which is controlled by two dominant complementary genes, Un a and Un b. Two dominant complementary genes, Cl a and Cl b have been found controlling clustered habit.One of the complementary genes for clustered habit, Cl a was linked with one of the complementary genes for uneven kernel, Un a with a c.o. value of 22.1 per cent. This linkage has been assigned to I linkage group in indica rice.The long glume gene g showed 22.2 per cent linkage with oed rice gene, Rc. It was further found linked with one of the complementary genes for uneven kernel, Un b (17.8 per cent) and one of the duplicate recessive genes for long palea, lp 1 (30.2 per cent). The cross-over value between Ub b and lp 1 was 11.5 per cent. The gene order appeared to be lp 1-Un b-g-Rc. These linked genes have tentatively been assigned to IV linkage group in indica rice.  相似文献   
78.
This article reports on the effects of fabric constructional factors such as fabric sett, warp tension, back rest position, and pick insertion rate, on the warp-way and weft-way shrinkages of a three-up-one-down twill woven fabric using a Taguchi design of experiments. It was observed that the fabric shrinkage in the warp direction was mostly affected by the change in the number of picks per inch, followed by warp tension, number of ends per inch, number of picks per minute, and back rest position, respectively. The fabric shrinkage in the weft direction was found to be mostly affected by the change in number of ends per inch, followed by number of picks per inch, back rest position, number of picks per minute, respectively and least affected by warp tension. It was observed that the aforesaid five factors were able to explain 99.02 % and 82.81 % of the total variation of fabric shrinkage in the warp and weft directions, respectively.  相似文献   
79.
In field and greenhouse experiments Ethrel (2-chloroethyl phosphonic acid) was tested for its male garnetocidal effects on pearl millet (Pennisetum americanum) and its subsequent effects on ergot development. Application of Ethrel at 2000 ppm at late boot or early protogyny was the most effective for inducing male sterility in the hybrid, EJ 104. Female fertility in a male sterile line, however, was not affected by Ethrel treatment. Ethrel at 2030 ppm applied at ihe late boot stage resulted1 in partial paniele exsertion, and reduced plant height anc. panide length. In vitro Ethrel (2000 ppm) completely inhibned pollen germination but did not affect germination of conidia of Claviceps fusiformis, the causal agent of ergot of pearl millet. Ergot resistance or susceptibility in pearl millet lines was not affected., probably because Ethrel could not induce complete male sterility.  相似文献   
80.
Influence of phosphate on cadmium sorption by calcium carbonate   总被引:1,自引:0,他引:1  
S.K. Thakur  N.K. Tomar  S.B. Pandeya 《Geoderma》2006,130(3-4):240-249
Laboratory investigation was conducted to investigate the mechanism of cadmium sorption by pure calcium carbonate and to examine whether, reaction products of phosphate with calcium carbonate serve as a sink for sorption of toxic heavy metal cations like cadmium. The phosphatization of calcium carbonate (G.R) was carried out by treating it with orthophosphoric acid in Ca:P ratio of 5:3, 3:2, 4:3 and 1:1, representing the Ca–P ratios of carbonate apatite, tricalcium phosphate, octacalcium phosphate and dicalcium phosphate and then equilibrated for two months. The X-ray diffraction of the phosphate reaction products revealed that calcite along with monetite, brushite and carbonate apatite were present in each case. The cadmium was effectively retained on CaCO3 by the mechanism of chemisorption at lower Cd2+ concentrations as the pH of the equilibrium system remained constant (8.6) up to initial Cd2+ concentrations of 10−4 mol, coinciding to 100% sorption of Cd2+ from the solution. At higher concentrations, precipitation of CdCO3 on CaCO3 surface or as a separate phase predominated. Enrichment of CaCO3 with P reduced the Cd-sorption. The chemisorption of Cd probably involved the exchange of Ca2+ by Cd2+ from CaCO3 surface. The Cd2+ concentration in equilibrium solution followed the solubility diagram of CdCO3 at pH ≤ 8.6, whereas the concentration of Ca2+ started deviating from the solubility line at pH ≤ 8.2.  相似文献   
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