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1.
A study was performed to assess the preference of fourteen mango cultivars for fruit flies and their management by bagging. So the choice of Tephritid flies to mango cultivars during fruiting phase is crucial. Fourteen different cultivars of mango viz., ‘Dusehri’, ‘Malda’, ‘Langra’ early cultivars, ‘Chaunsa’, ‘Fajri Klan’, ‘Sensation’ medium whereas ‘Sanglakhi’, ‘Retaul-12’, ‘Mehmood Khan’, ‘Tukhmi’, ‘Kala Chaunsa’, ‘Chitta Chaunsa’, ‘Dai Wala’ and ‘Sobey De Ting’ late cultivars were assessed for their suitability for fruit flies. The results indicate that the population density of fruit flies was higher on late cultivars like ‘Sanglakhi’ (20.61 percent), ‘Mehmood Khan’ (20.22 percent) and ‘Reutal-12’ (19.92 percent) were proved to be highly susceptible to fruit flies. Among these the cultivar ‘Reutal-12’ was selected being commercial and future cultivar for the management of fruit flies through bagging. The results reported that the attack of tephritid fruit flies and other insect pests were zero in bagged fruits as compared with control. It was further recorded that the bagged fruits has maximum average fruit weight i.e. 203.50 and 197.83 g per fruit was noted in those treatments where butter paper bag and brown paper bag was wrapped with better coloration as compared with un-bagged fruit with 159.5 g per fruit. Similarly, on an average fruit length were more i.e. 90.17, 91.33 mm in bagged fruit and 85.33 in un-bagged fruits. Furthermore, bagged fruits have zero incidence of disease with reduced fruit crack, fruit sunburn, mechanical damage, bird damage, fruit blemished and agrochemical residues on the fruit. So, it is concluded that the special attention should be given on ‘Reutal-12’ for the management of fruit flies when devising an IPM program for the control of fruit flies. Further, bagging has proved to be the good agricultural practices for the production of quality mango.  相似文献   
2.
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug.  相似文献   
3.
Genetic analysis of the raffinose oligosaccharide pathway in lentil seeds   总被引:2,自引:0,他引:2  
Two lentil (Lens culinaris) cultivars, Syrian Local Large (SLL) and PANT-L-406 (PL), have been used to study the genetics of the raffinose family of oligosaccharides (RFO) and a related compound, ciceritol, which is a galactosyl cyclitol. The RFO and ciceritol are the major soluble -galactosides in lentil seeds. Crosses were made between the two lentil lines and the patterns of inheritance for the total -galactoside content and for individual RFO compounds (raffinose, stachyose, verbascose) and ciceritol were determined in the embryos and seed coats from single seeds of the reciprocal F1s, the F2s and ten F3 families. The inheritance patterns for each of the -galactosides were complex and much of this complexity was attributed to an interaction between the embryo and its surrounding testa. A clear-cut segregation pattern was observed for verbascose. This was the result of PL embryos having very low, or no, verbascose. The F2 embryos had a segregation ratio of 3 high to 1 low level for this compound, suggesting that within this cross a low verbascose content was determined by a single recessive gene. There was good evidence from the F2 and F3 generations of a negative correlation between low levels of verbascose and high levels of ciceritol, which suggests a metabolic link between the RFO pathway and the pathway leading to ciceritol. The data are discussed in terms of defining strategies for genetically manipulating the-galactoside composition in lentil seeds, such that their negative effects on nutrition may be overcome without reducing significantly their positive role in abiotic stress resistance.  相似文献   
4.
The electronic circular dichroism (ECD) spectra of two sesquiterpenoids ( 1 and 2 ) related to oplopanone, obtained from a methanolic extract of the plant Serphidium stenocephalum (Artemisia stenocephala), were measured and reproduced by means of time‐dependent density functional theory (TDDFT) calculations, establishing their absolute configuration. The application of ketone octant rule for carbonyl n‐π* ECD band to compounds 1 and 2 , which include an acyclic carbonyl group, was critically assessed. The peculiar oplopanone skeleton makes a straightforward application of the octant rule impossible, because of the uncertainty related to the shape of the so‐called third nodal surface separating front and back octants. The various group contributions to the carbonyl n‐π* ECD band were estimated with TDDFT calculations on selected molecular models obtained by consecutive dissections from 1 . Chirality 26:39–43, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
5.
Occurrence and Genome Analysis of Cucurbit chlorotic yellows virus in Iran   总被引:1,自引:0,他引:1  
In 2011 and 2012, several cucurbit‐growing regions of Iran were surveyed and samples with symptoms similar to those induced by Cucurbit chlorotic yellows virus (CCYV) were collected. The pathogen was transmitted to cucumber and melon under greenhouse conditions by whiteflies (Bemisia tabaci). RT‐PCR using designed CCYV‐specific primer pair (CCYV‐F/CCYV‐R) resulted in amplification of the predicted size DNA fragment (870 bp) for the coat protein (CP) gene in samples collected from Boushehr, Eyvanakay and Varamin. Nucleotide sequences of the CP of the three Iranian CCYV isolates were compared with five CCYV isolates obtained from GenBank and analysed. Phylogenetically, all CCYV isolates clustered in two groups; Group I is composed of five non‐Iranian isolates from China, Lebanon, Japan, Sudan and Taiwan, and the three Iranian isolates formed Group 2. Among Iranian isolates, the Eyvanakay isolate clustered in a distinct clade with the Boushehr and Varamin isolates. A phylogenetic tree based on amino acid identity of CP showed that CCYV was closely related to Lettuce chlorosis virus (LCV), Bean yellow disorder virus (BnYDV) and Cucurbit yellow stunting disorder virus (CYSDV). This is the first report of CCYV in Iran.  相似文献   
6.
Most of the commercialized Bt crops express cry genes under 35S promoter that induces strong gene expression in all plant parts. However, targeted foreign gene expression in plants is esteemed more important as public may be likely to accept ‘less intrusive’ expression of transgene. We developed plant expression constructs harboring cry1Ac gene under control of wound-inducible promoter (AoPR1) to confine Bt gene expression in insect wounding parts of the plants in comparison with cry1Ac gene under the control of 35S promoter. The constructs were used to transform four Turkish cotton cultivars (GSN-12, STN-468, Ozbek-100 and Ayhan-107) through Agrobacterium tumefaciens strains GV2260 containing binary vectors p35SAcBAR.101 and AoPR1AcBAR.101 harboring cry1Ac gene under control of 35S and AoPR1, respectively. Phosphinothricin (PPT) was used at concentration of 5 mg L?1 for selection of primary transformants. The primary transformants were analyzed for transgene presence and expression standard molecular techniques. The transformants exhibited appreciable mortality rates against larvae of Spodoptera exigua and S. littoralis. It was found that mechanical wounding of T 1 transgenic plants was effective in inducing expression of cry1Ac protein as accumulated levels of cry1Ac protein increased during post-wounding period. We conclude that use of wound-inducible promoter to drive insecticidal gene(s) can be regarded as a valuable insect-resistant management strategy since the promoter activity is limited to insect biting sites of plant. There is no Bt toxin accumulation in unwounded plant organs, seed and crop residues, cotton products and by-products, thus minimizing food and environmental concerns.  相似文献   
7.
Comparative effects of potassium chloride and potassium sulfate at various levels of potassium on the performance of ARZ variety of wheat were studied at Agriculture Research Station Dera Ismail Khan, N.W.F.P., Pakistan. The experiment was laid out in three different rotationsviz, rice-wheat, maize-wheat and fallow-wheat. Potassic fertilizers were applied at the rate of 0, 37, 74, 111 and 148 kg k/ha alongwith the basal dose of 135 kgN plus 44 kg P/ha. Wheat yield data showed that the application of 37 kg K/ha of potassium chloride was found better in case of rice-wheat and fallow-wheat rotation and 37 kg K/ha of potassium sulfate for maize-wheat rotation. On the average of the three rotations, potassium sulfate at the rate of 74 kg K/ha (90 kg K2O/ha) was found better and economical. Both the sources were almost equally effective but potassium sulfate out-yielded potassium chloride. Protein content of grains was significantly increased due to K application irrespective of the source and potassium sulfate was found with significantly higher protein content than potassium chloride.  相似文献   
8.
Crispins A (1) and B (2), two new glycosphingolipids, were isolated from the whole plant Buddleja crispa, along with three known compounds: alpha-amyrin, linoleic acid, and stigmasterol. Their structures were elucidated by chemical and spectroscopic techniques. Both 1 and 2 showed significant inhibitory activity against alpha-chymotrypsin in a concentration-dependent manner.  相似文献   
9.
Four new pterocarpans, atricarpan A (=(-)-1,2-dihydroxy-4-(hydroxymethyl)-3,9-dimethoxypterocarpan; 1), atricarpan B (=(-)-2,3-ethylenedioxy)-1,4-dihydroxy-9-methoxypterocarpan; 2), atricarpan C (=(-)-1,9-dimethoxypterocarpan-3-carboxylic acid; 3), and atricarpan D (=(-)-2,9-dimethoxy-4-(5-oxohexyl)pterocarpan; 4) were isolated from the BuOH extract of the whole plant of Zygophyllum eurypterum. The structure elucidations of those compounds were based primarily on 1D- and 2D-NMR analysis, including COSY, HMBC, and HMQC correlations. Compounds 1-4 also inhibited butyrylcholinesterase (BChE; EC 3.1.1.8) enzyme in a concentration-dependent manner with IC(50) values between 12.5-65.0 microM. Similarly, compounds 1 and 4 inhibited lipoxygenase (LOX; EC 1.13.11.12) and acetylcholinesterase (AChE; EC 3.1.1.7) enzymes with IC50 values of 13.5 and 20.5 muM, respectively.  相似文献   
10.
Heat‐shock proteins (HSP) are molecular chaperones for protein molecules. These proteins play an important role in protein–protein interactions such as, folding and assisting in the establishment of proper protein conformation and prevention of unwanted protein aggregation. A small HSP gene GHSP26 present in Gossypium arboreum responds to dehydration. In the present study, an attempt was made to overcome the problem of drought stress in cotton. A cDNA of GHSP26 was isolated from G. arboreum, cloned in plant expression vector, pCAMBIA‐1301 driven by the cauliflower mosaic virus 35S promoter and introduced into Gossypium hirsutum. The integration and expression studies of putative transgenic plants were performed through GUS assay; PCR from genomic DNA, and quantitative real‐time PCR analysis. Transgenic cotton plants showed an enhanced drought tolerance, suggesting that GHSP26 may play a role in plant responsiveness to drought. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
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