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891.
Zulfiqar Ahmad Shermeen Tahir Abdul Rehman Nabeel Khan Niazi Muhammad Abid Muhammad Amanullah 《Journal of plant nutrition》2015,38(12):1913-1928
The potential of encapsulated calcium carbide (ECC) in improving growth, yield and physiology of cotton under salinity was evaluated in pot experiment. Salinity was induced by sodium chloride (NaCl) at 0, 1250 and 2000 ppm. The ECC was applied at the rate of 0, 15, and 30 mg kg?1 soil. The results revealed that ECC improved number of branches, yield, shoot dry biomass, root dry biomass, by 57, 67, 40, 22, and 18% respectively, over control. Similarly, net photosynthesis, stomatal conductance nitrogen, phosphorus and potassium (N, P and K) concentration of shoot were enhanced by 38, 34, 7, 25 and 11% over control, respectively. The induction of new set of proteins ranging from 11 to 26 kDa was also observed at various levels of ECC and salinity stress. These results proved the efficacy of very lower concentrations of ethylene produced by ECC and showed the behavior of different parameters of cotton to it under saline stress. 相似文献
892.
Flamini G Bader A Cioni PL Katbeh-Bader A Morelli I 《Journal of agricultural and food chemistry》2004,52(3):572-576
Pistacia palaestina Boiss. (Pistacia terebinthus L. var. palaestina (Boiss.) Engl.) is a medicinal and foodstuff plant. The ripe fruits are used largely in the Middle East as a component of the so-called Zaatar, a mix of aromatic and food plants. Results of GC and GC-MS analyses of the essential oils of leaves, galls produced by Baizongia pistaciae (L.), and ripe and unripe fruits of Pistacia palaestinaBoiss. collected in Jordan are reported. Both qualitative and quantitative differences between different parts of the plant were observed. The oil was rich in monoterpenes, and the main constituents were alpha-pinene (63.1%) and myrcene (13.3%) in the leaves and alpha-pinene (49.4%), sabinene (22.8%), and limonene (8.1%) in the galls. (E)-Ocimene (33.8-41.3%), sabinene (20.3-24.1%), and (Z)-ocimene (3.8-13.0%) were the main ones in both unripe and ripe fruits. Sesquiterpenes have been detected in small quantities in leaves and fruits and in trace amounts in galls. 相似文献
893.
We examined the competitiveness of five effective Rhizobium leguminosarum biovar phaseoli strains in the nodulation of kidney beans (Phaseolus vulgaris L.), either alone or in pairwise combination, against the indigenous strains. The results showed that the introduced Rhizobium sp. strains (B2, B17, B36, T2, or CIAT 652) occupying 64–79% of the total nodules (as single inocula) were more competitive in nodulation than the native rhizobia. However, the competitiveness of the individual Rhizobium sp. strain either increased or decreased when used in a pairwise combination of double-strain inocula. For example, strain B17, although quite competitive against the indigenous population (68% nodule occupancy), became poorly competitive in the presence of strain B2 (reduced from 68 to 2.5%). A similar reduction in nodule occupancy by strain B17 was observed in the presence of B36 or CIAT 652, indicating that two competitive strains may not always be compatible. These results suggest that it is important to co-select competitive as well as compatible rhizobia for multistrain inoculant formulation. 相似文献
894.
Nitrogenase activity (by acetylene reduction assay) has been found on the roots and in the rhizosphere-soil of various plant species collected from dune soils (Table 1.) located on the west coast of Denmark. Out of twelve plant species, five plant species (Deschampsia flexuosa, Ammophila arenaria, Calluna vulgaris, Empetrum nigrum and Corynephorus canescens) revealed a positive nitrogenase activity. Among these five, three were temperate grasses. Except Ammophila arenaria, all four plant species were collected from old sand dune and showed nitrogenase activity on roots as well as in their rhizosphere soil, Ammophila arenaria was collected from fresh sand dune and exhibited nitrogenase activity only on roots (Table 2). 相似文献
895.
In vivo interspecific pollinations were performed and immature seed development investigated by histological methods in order to study crossability barrier(s) in Cicer L. species wide hybridization. Seven of the eight wild annual Cicer species, belonging to the secondary and tertiary gene pools, were used in reciprocal crosses with the cultivated chickpea. It was confirmed that the zygote was formed in all interspecific crosses. The embryos showed continued and retarded growth at different rate in various crosses, but eventually aborted at an early pro-embryo stage in all crosses except C. arietinum L. ×C. echinospermum Dav. Reciprocal cross differences were observed in early embryo growth rate and could have implications in obtaining hybrids. This study further emphasizes the necessity for developing appropriate and efficient in vitro procedures for rescuing immature globular hybrid pro-embryos, which will make the wild Cicer gene resources amenable to chickpea improvement. 相似文献
896.
Summary The uptake of labelled and unlabelled N by wheat was measured in a field experiment using 15N-labelled ammonium nitrate fertilizer. The dry matter yield and N yields were significantly increased with fertilizer N application compared to those from unfertilized soil. The uptake of applied N by wheat ranged between 25 and 34%. Fertilizer N application increased the uptake of unlabelled soil N which was attributed to a positive priming effect or added N interaction. The added N interaction observed by applying 20, 60, and 120 kg fertilizer N was 11.4, 19.1, and 27.9 kg, corresponding to 26, 44 and 64%, respectively of the N taken up from unfertilized soil. The A values did not alter with the increase in fertilizer N application. The observed added N interaction may have been the result of pool substitution whereby added labelled fertilizer N stood proxy for unlabelled soil N. A significant correlation coefficient (r=0.996**) between the uptake of soil N and the dry matter yield showed that soil N was more important than fertilizer N in wheat production. 相似文献
897.
The objectives of this work were to analyze the physical and mechanical properties of parallel strand lumber (PSL) made from
Calcutta bamboo. Based on the surface characteristics (Ahmad and Kamke 2003) and physical and mechanical properties (Ahmad and Kamke 2005) observed in previous work, a prototype PSL from Calcutta bamboo was manufactured and tested in the laboratory. Physical
properties determined were dimensional stability and water absorption. The mechanical tests carried out were in compression
and bending. Ultimate stress, stress at proportional limit, and modulus of elasticity were determined and compared to structural
composite lumber (SCL) from several timber species produced by other researchers and manufacturers in the United States. The
PSL produced was also exposed to accelerated aging process in order to assess its durability under extreme condition. PSL
produced in the laboratory was stable in dimension. The mechanical characteristics compare favorably to SCL produced in other
studies and SCL products available in the United States. The accelerated aging process was found to reduce the bending strength
but no significant difference was detected in bending stiffness, and compression strength and stiffness. This is a promising
indication of the suitability of Calcutta bamboo as raw material for structural composite products. 相似文献
898.
Schneider P. und Ahmad Schah Djalai 《Journal of pest science》1971,44(12):190
Ohne Zusammenfassung 相似文献
899.
R. Ahmad 《Journal of pest science》1977,50(10):150-151
On the knowledge of Hyperodes bonariensis Kuschel (Col., Curculionidae) and its antagonists in Argentina
Studies were made on damage ofHyperodes bonariensis as a pest of pasture plants and on incidence of its parasites and predators. Among its natural enemies,Patasson atomarius (Breth.) (Mymaridae, parasitic on eggs) appeared to be polyphagous, having a good potential rate of increase and substantical ecological tolerance and seemed to be a promising parasite.Sericophanes obscuricornis Popp. (Miridae),Nabis punctipennis Blanch. (Nabidae),Philonthus sp. (Staphylinidae) (predaceous on eggs),Pterostichus aereus (Dej.),Pt. unistriatus (Dej.),Barypus clivinoides Curt.,Cnemalobus gavi Putz.,Metius blandus (Dej.) andM. malachiticus (Dej.) (Carabidae, predaceous on adult weevils) destroyed the host to some extent, but they are not of much importance in regulating the population of this pest. 相似文献
900.
Nef protein of HIV-1 is a transcriptional repressor of HIV-1 LTR 总被引:73,自引:0,他引:73