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1.
The seeds of two soybean cultivars viz., Pusa-16 and PK-1042 were treated with 15, 30, and 45 kR of gamma rays, three concentrations of ethyl methane sulphonate (EMS) (0.1%, 0.2%, and 0.3%), and their combinations. Various morphological mutants were recorded in M2 and M3 generations. These morphological mutants were named on the basis of the part of the plant body affected. Eight different morphological mutants, i.e., tall, dwarf, gigas, black pod, smooth pod, black spotted seed, bold seeded, and early maturing were isolated. Among them, early maturing and bold seeded mutants had the potential to be incorporated into breeding programs.  相似文献   
2.
Abstract

The economic threshold level of the mustard aphid, Lipaphis erysimi (Kaltenbach) was determined on the radish seed crop, var Punjab Sufed. Spraying oxydemeton methyl at 300 g a.i./ ha, was monitored at arbitrary set aphid levels from 25 to 150 aphids/plant. The maximum cost benefit ratio (1: 13.1) was achieved at an aphid level of 50 per plant, requiring three sprays. Spraying in the middle of February was the most crucial, as delay of 7 days from this stage resulted in significant decreases in yield in the fixed spray schedule and at the 75‐aphid level.  相似文献   
3.
Field experiments were conducted at the Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso, Nigeria in 2007 and 2008 to determine the effects of phosphorus fertilizer application on performance of intercropped maize and soybean. The experiments, arranged as a split plot in a randomized complete block design, replicated four times. A cropping system with sole maize, sole soybean and maize/soybean intercrop formed the main plot treatments while P rates with 0, 15 and 30 kg P2O5 ha?1 were the subplot treatments. For both years, neither P fertilizer application nor cropping systems had a significant effect on maize grain yield. However, soybean grain yield was significantly higher (92.3% in 2007 and 44.5% in 2008) under sole cropping than under maize/soybean intercropping. On average, N fixed by soybean increased with the increase in P rate (from 51.8% without P to 60.5% with 30 P), but there was no significant difference in N fixed by sole soybean and soybean/maize intercrop. However, the interaction effect on N fixed between cropping systems and P rates was significant (P ≤ 0.05). N, P and K contents in maize grain were significantly higher (>100%) in intercropped maize than in sole maize. The cropping systems had no significant effect on post-harvest soil chemical characteristics. The land equivalent ratio was 1.52 in 2007 and 1.78 in 2008. The result shows that in utilizing legumes for N enrichment, the alleviation of P deficiency can enhance N2-fixation by legumes. Furthermore, P replenishment in a maize/soybean intercrop may improve maize grain quality even though yield is not increased.  相似文献   
4.
The effects of cultivating and incorporating residues of previous tropical kudzu (Pueraria phaseoloides) and soybean (Glycine max) with application of NPK fertilizer on yam performance were evaluated at the teaching and research farm, LAUTECH, Nigeria. There were nine treatments: incorporation of legume residues (5 t DM ha?1), application of recommended fertilizer rate for yam (90–50–75 kg NPK ha?1) in the zone or 50% of recommended rate (45–25–37.5 kg NPK ha?1), alone and in combination with residues and a control without residues or fertilizer in a randomized complete block design. Cultivation of previous legumes reduced soil nematode population (>200%) compared with no legumes. For both years, application of Pueraria residues improved tuber yield by an average of 15.8% compared with control. Fertilizer application enhanced arbuscular mycorrhizal (AM) colonization of yam roots but AM colonization was lower (~50%) in plots where Pueraria residues were incorporated compared with other plots. Combined application of plant residues with fertilizer improved soil organic carbon, total N, exchangeable Ca and Mg compared with application of NPK fertilizer. From these results, it is concluded that half of the recommended NPK rate may be adequate and incorporation of residues with reduced NPK fertilizer application may be a sustainable soil fertility management option for continuous yam production.  相似文献   
5.
The effect of gamma rays, ethyl methane sulphonate, and their three combinations on various cytological parameters in M1 generation was studied in two soybean cultivars, Pusa-16 and PK-1042. Combined treatments exhibited high meiotic abnormalities in Pusa-16 as compared with the individual treatments of ethyl methane sulphonate and gamma rays. In PK-1042 the highest frequency of meiotic abnormalities was exhibited by gamma rays, while in Pusa-16 the frequencies of univalents were high as compared with other meiotic abnormalities. Fragments/bridges, laggards, ring and rod bivalents were other types of meiotic abnormalities that were noticed in both the cultivars. The frequencies of irregular cells in the two cultivars were high in combined treatments followed by ethyl methane sulphonate and gamma rays. The highest percentage of pollen sterility was exhibited by the combined treatments and the lowest was exhibited by gamma rays. In Pusa-16, the increase in doses of gamma rays and ethyl methane sulphonate increased the pollen sterility percentage, while in the combined treatments, the increase was noticed up to the intermediate dose and then gradually decreased at higher doses. On the other hand, in PK-1042 the increase in ethyl methane sulphonate dose increased sterility percentage, while no definite trend was noticed in gamma rays and combined treatments.  相似文献   
6.
The phenotypic response of two soybean cultivars to a chemical mutagen (ethyl methane sulphonate, EMS), physical mutagen (gamma rays) and their combinations were studied in M1 and M2 generations and the frequency and spectrum of chlorophyll mutations were worked out. Combined treatment was found to be more effective in inducing chlorophyll mutations compared to individual treatments of gamma rays and EMS in both the cultivars. As far as the spectrum of chlorophyll mutations is concerned, a wider spectrum in both the cultivars was observed in 45 kR + 0.2% EMS combined treatment.  相似文献   
7.
8.
Sugar-based molecules such as heparins or natural heparan sulfate polysaccharides have been developed and widely studied for controlling heparanase (HPSE) enzymatic activity, a key player in extracellular matrix remodelling during cancer pathogenesis. However, non-enzymatic functions of HPSE have also been described in tumour mechanisms. Given their versatile properties, we hypothesized that sugar-based inhibitors may interfere with enzymatic but also non-enzymatic HPSE activities. In this work, we assessed the effects of an original marine λ-carrageenan derived oligosaccharide (λ-CO) we previously described, along with those of its native counterpart and heparins, on cell viability, proliferation, migration, and invasion of MDA-MB-231 breast cancer cells but also of sh-MDA-MB-231 cells, in which the expression of HPSE was selectively downregulated. We observed no cytotoxic and no anti-proliferative effects of our compounds but surprisingly λ-CO was the most efficient to reduce cell migration and invasion compared with heparins, and in a HPSE-dependent manner. We provided evidence that λ-CO tightly controlled a HPSE/MMP-14/MMP-2 axis, leading to reduced MMP-2 activity. Altogether, this study highlights λ-CO as a potent HPSE “modulator” capable of reducing not only the enzymatic activity of HPSE but also the functions controlled by the HPSE levels.  相似文献   
9.
Seven strains of Leptospira interrogans belonging to seven different serogroups, and one strain of Leptospira biflexa were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with gradient gels and immunoblotting with hyperimmune rabbit sera raised against each strain. The molecular masses of the proteins were calculated with a polynomial regression model. The SDS-PAGE patterns of the L. interrogans strains were similar and characterized by 24 common bands. This profile was not found for L. biflexa. The immunoblots obtained either with the seven anti-L. interrogans sera or the anti-L. biflexa serum allowed a clear distinction between the two species. Taken as a whole, the L. interrogans strain patterns revealed by the seven anti-L. interrogans sera were similar, sharing eight common major bands. A serovar- or serogroup-specific antigenic zone, ranging from 21 to 26 kDa, was also identified.  相似文献   
10.
The ethylacetate and n-butanol fractions of ethanolic extract of Platanus orientalis leaves led to the isolation of new acylated flavonol glycoside as 3',5,7-trihydroxy-4'-methoxyflavonol 3-[O-2-O-(2,4-Dihydroxy)-E-cinnamoyl-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl (1→2)]-β-D-glucopyranoside, along with seven known compounds. All the compounds were characterized by NMR including 2D NMR techniques. The isolates were evaluated for NF-κB, nitric oxide (NO), aromatase and QR2 chemoprevention activities and some of them appeared to be modestly active.  相似文献   
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