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Abstract

In the present study we evaluate the feasibility of using untreated industrial sewage sludge by liming before use as a fertilizer, produced in Pakistan. In a pots experiment, limed industrial sewage sludge (LSW) and non-limed sewage sludge (NLSW), were amended with soil separately and grown sorghum. After maturity, the sorghum grains were analysed for total contents of potentially toxic metals (TPTM), As, Cd, Cr, Cu, Ni, Pb and Zn. The proportion of different mobility fractions of each element in LWS and NLSW, a modified BCR sequential extraction procedure (Community Bureau of Reference) and single extractions with mild extractants (deionized water and CaCl2) were used. In LSW, the availability of most of the elements under study was reduced, probably due to the increased pH of soil, while this was the reverse in the cases of Cd and Cu, their mobility was slightly increased by lime-treated sludge. The sorghum grains grown in LSW have low level As, Cr, Ni, Pb and Zn as compared to grains grown in NLSW, except Cu and Cd, which, however, never exceeded legal limits. Thus the research showed that liming, by augmenting soil alkalinity, allows a safe agricultural use even of industrial sludge, which is environmentally hazardous for its great content of heavy metals.  相似文献   
33.
Şahin  Çiğdem  Gözel  Uğur 《Phytoparasitica》2021,49(4):613-621
Phytoparasitica - Entomopathogenic nematodes (EPN) have an important potential in the biological control of agricultural soil pests. Efficacy and persistence of native EPN species from Turkey were...  相似文献   
34.
DNA markers in chickpea, targetting resistance genes for different races of Fusarium oxysporum f.sp. ciceris (Foc), have been identified in chickpea, but validation of these markers is essential for effective use in resistance breeding. In view of this, different simple sequence repeats (SSR) markers were analysed in Pakistani germplasm including induced mutants and some local lines. Most of the SSR markers showed good correlation with phenotypic evaluation of genotypes to different races of Foc and may be used effectively in resistance breeding, except those markers for race 3. Markers for race 3 showed deviations from phenotypic data and the reason might be that race 3 is actually Fusarium proliferatum as reported recently and resistance to this race might involve some other major resistance genes. Poor correlation of markers with foc-3 on LG2 in our study and a recent report of independent segregation of foc-2 and foc-3 in near isogenic lines suggested that linkage distances among different resistance genes need further investigation. Moreover three Pakistani mutant lines (97477, CM444/92 and CM368/93) depicted high levels of resistance to Foc races and can be deployed as a valuable source in resistance breeding programmes.  相似文献   
35.
The objective of this experiment was to test the effect of supplementation of analogues of methionine 2-hydroxy-4-methylthio butanoic acid isopropyl ester (HMBi) on growth, digestibility, antioxidant index, abundance and composition of rumen bacterial community in Xiangdong Black Goats. Thirty-six growing Xiangdong Black Goats were divided into four groups in such a way that each group had three replicate and each replicate had three animals. Experimental groups were assigned four levels of HMBi in basal diet: 0% HMBi (on dietary DM basis); 0.05% HMBi; 0.10% HMBi and 0.20% HMBi. Goats fed 0.10% HMBi in basal diet had higher average daily weight gain (p < .05). Goats fed 0.05% HMBi had higher apparent digestibility of gross energy (p < .01). The group 0% HMBi supplementation had a higher level of superoxide dismutase and malondialdehyde (p < .01). The goats fed 0.20% HMBi in basal diet had a higher level of insulin and leptin (p < .01) than 0% HMBi supplementation goats. 16S rRNA high-throughput sequencing analysis revealed similarities in the community composition, species diversity and relative abundance of dominant bacteria at the phylum and genus levels among the four groups. In conclusion, HMBi supplementation has no negative effect on apparent digestibility, antioxidant index and the ruminal bacteria composition. Therefore, 0.10% supplementation of HMBi is recommended in the diet of goats to improve the growth performance.  相似文献   
36.
The number of intensive livestock and poultry farms is expected to increase substantially in future because of consumer demand. Unfortunately, such demand also results in a great deal of manure being generated, which threatens the environment if it is not properly managed. Concurrent developments in biotransformation of these wastes with the black soldier fly(BSF), Hermetia illucens(L.)(Diptera: Stratiomydiae), demonstrates such concerns can be abated, while also producing products(e.g., protein, chitin, biodiesel, and fertilizer) of value. In this review, we analyzed the factors influencing black soldier fly larvae(BSFL) conversion processes, the role of microorganisms, and the mechanisms used by BSFL when converting livestock and poultry manure into these valuable products. The effects of BSFL conversion technology on reducing the hazards of such materials and their associated pathogens are reviewed, and the economics of livestock and poultry manure conversion by BSF larvae is discussed.  相似文献   
37.
Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage (CT) is more productive than zero tillage (ZT)/reduced tillage (RT). Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC (108 g a.i. ha?1), lactofen 24 EC (168 g a.i. ha?1), haloxyfop 10.8 EC + lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I. Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop + lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides × CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides × CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I. Khan.  相似文献   
38.
Pre-breeding and elite breeding are two steps in creating high yielding sunflower hybrids that differ in well established procedures and selection methods. However, a methodology that bridge efficient use of introgression lines as product of pre-breeding procedures and their crossing to elite inbreed lines, is not yet very well established. Therefore, the development of cost- and time-efficient methods for the determination of best parent heterosis and the use of best inbred lines in crosses with introgression lines for obtaining high-yielding and stable hybrids is highly desirable. In this regard, sixteen Cytoplasmic Male Sterile (CMS) inbred lines (A) derived from four heterogeneous interspecific lines originating from three annual: H. debilis silvestris (DEB-SIL), H. praecox runyoni (PRA-RUN), H. deserticola (DES) and one perennial H. resinosus (RES) wild species were evaluated. Seven agronomic traits were measured over a period of 2 years and 38 DNA loci were analysed, in order to compare four different methods for the estimation of best parent heterosis (BPH). New inbred lines were characterized by Principal Component Analysis (PCA) of morphological traits and Principal Coordinate Analysis (PCoA) of molecular marker data. Line?×?tester mating design was used to evaluate General Combining Ability (GCA), while Genetic Distance (GC) estimated by markers was evaluated as a predictor of BPH by Locally Weighted Sequential Smoothing (LOESS). Analysis of combining ability is one of the most important tools breeders use to identify superior inbred lines on the basis of their performance in hybrid combinations. Results obtained in this research show that PCA of morphological and PCoA of molecular marker data on parental lines are generally in agreement with GCA effects for examined traits. GD versus BPH relationships indicate that intermediate to high GD between parental lines was optimal for best heterotic effects of most traits. In this study, we show that the combination of the PCA of morphological data, PCoA of molecular marker data and GD between parental lines is fast and affordable, giving the most important information for parental choice of introgression and elite lines in sunflower breeding programs.  相似文献   
39.
Water, Air, & Soil Pollution - Sustainable groundwater quality has become a major concern for the agro-based country like Bangladesh. Integrated approaches of various irrigation water quality...  相似文献   
40.
This study evaluated the effects of rice straw and water regimes on CH4 and N2O emissions from paddy fields for two rice growing seasons (summer 2014 and spring 2015). Water regimes included alternating wet–dry irrigation (AWD) maintained at three levels (–5 cm, – 10 cm and –15 cm) in comparison to continuous flooding irrigation (CF). Rice straw (5 t ha–1) was incorporated into the top soil (0 – 15 cm), distributed and burned in situ. Results showed that using burned in situ rice straw was found to reduce seasonal cumulative CH4 emission (24–34% in summer; 18–28% in spring), N2O emission (21–32% in summer; 22–29% in spring) and lower rice yield (8–9%) than rice straw incorporation into top soil. AWD methods reduced the amount of CH4 production (22.6–41.5%) and increased N2O emission (25–26%) without any decrease in rice yield. Rice straw incorporation into the top soil with AWD had higher water productivity (23–37%) than rice straw when burned in situ with CF. The results conclude that AWD and rice straw management can be employed as mitigation strategy for CH4 and N2O emissions from paddy fields in Central Vietnam.  相似文献   
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