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121.
Samples of malformed and healthy panicles of mango (Mangifera indica L.) as well as leaves and shoots bearing them were collected at different stages of development (fully swollen buds, bud inception, fully grown panicles prior to full bloom and at full bloom) over two consecutive years and were analysed for their macro- and micronutrient status. In addition, malformed and healthy seedlings were collected and analysed. Malformed panicles were found to be significantly higher in N at all the developmental stages except at bud inception. Phosphorus and K also tended to accumulate in malformed panicles at later stages of their development. In general, malformed panicles exhibited lower levels of P, K and Ca than healthy panicles. The differences in levels of Mg and S in malformed and healthy panicles were not significant. All micronutrients were in much lower concentrations in malformed panicles except for Mn which appears to accumulate in malformed panicles particularly at the early stages of development. The leaves on the shoots bearing malformed panicles also showed a tendency to accumulate N, while P, Mg and S were always higher in leaves on shoots bearing healthy panicles. The leaves on shoots bearing healthy panicles had lower levels of Fe, Cu and Mn, whereas levels of Zn and B tended to be higher in leaves on shoots bearing malformed panicles. The nutrient concentration differences between the two kinds of shoots were generally nonsignificant (P=0.05), except for K and S which were significantly lower in shoots bearing malformed panicles. The shoots bearing malformed panicles showed significantly (P=0.05) higher levels of almost all nutrients compared with shoots bearing healthy panicles. Vegetative malformation was found to be associated significantly (p=0.05) with higher amounts of all nutrients except Ca which was significantly higher in healthy seedlings. The present study, therefore, seems to point to lower Ca as one of the pre-disposing factors causing malformation in mango.A part of Ph.D. thesis of the senior author.A part of Ph.D. thesis of the senior author. 相似文献
122.
The response of soil exchangeable sodium percentage levels to nitrate reductase activity, nitrite reductase activity, free proline, DNA, RNA, chlorophyll a and b contents and yield components in lentil (Lens esculenta Moench)cv. PL 406 was studied in a replicated pot experiment. All the biochemical observations were recorded at four growth stages i.e. 30, 60, 90 and 120 days after sowing (DAS). Germination occurred up to exhangeable sodium percentage of 30, but plants survived only up to 25. With increasing exchangeable sodium percentage, there was a continuous decrease in chlorophyll a and b content, nitrate and nitrite reductase enzyme activities and DNA and RNA content. Increasing level of sodicity enhanced the free proline content up to 60 DAS, after which values fell.Number of pods per plant, 1000 grain weight and grain yield were significantly reduced with increasing level of sodicity, but the number of grains per pod was not affected. 相似文献
123.
Flavonoid glycosides from Cassia alata. 总被引:1,自引:0,他引:1
Two new glycosides, chrysoeriol-7-O-(2"-O-beta-D-mannopyranosyl)-beta-D-allopyranos ide and rhamnetin-3-O-(2"-O-beta-D-mannopyranosyl)-beta-D-allopyranosid e, were isolated from the seeds of Cassia alata. The structures were established on the basis of chemical evidence and spectroscopic methods, especially NMR. 相似文献
124.
Characterization of Ribonuclease Activity of Three S-Allele-Associated Proteins of Petunia inflata 总被引:11,自引:1,他引:10
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Three S-allele-associated proteins (S-proteins) of Petunia inflata, a species with gametophytic self-incompatibility, were previously found to share sequence similarity with two fungal ribonucleases, RNase T2 and RNase Rh. In this study, the S-proteins from P. inflata plants of S1S2 and S2S3 genotypes were purified to homogeneity by gel filtration and cation-exchange chromatography, and their enzymatic properties were characterized. The three S-proteins (S1, S2, and S3), with pairwise sequence identity ranging from 73.1 to 80.5%, were similar in most of the enzymatic properties characterized. The ribonuclease activity had a pH optimum of 7.0 and a temperature optimum of 50°C. Diethylpyrocarbonate at 1 millimolar almost completely abolished the ribonuclease activity; cupric sulfate and zinc sulfate at 1 millimolar reduced the ribonuclease activity of the three S-proteins by 50 to 75%. EDTA and RNasin had no inhibitory effect. All three S-proteins hydrolyzed polycytidylic acid preferentially, but varied in their nucleolytic activity toward polyadenylic acid and polyuridylic acid. 相似文献
125.
Summary The cytochemical localization of ATPase activity has been investigated in maize root cells using both lead and cerium-based capture methods. With both methods, staining at the plasma membrane was observed in all cells of the root, although the precipitate obtained with cerium was more uniform and granular than that with lead. Controls using no substrate or no magnesium, -glycerophosphate to replace ATP, vanadate or boiled tissue generally showed little or no staining. However, biochemical studies on purified plasma membrane fractions showed that ATPase activity was markedly inhibited by fixation, particularly by glutaraldehyde, and also by lead and cerium ions. Non-enzymic hydrolysis of ATP by cerium was greater than that by lead. The value and limitations of these procedures for the localization of plasma membrane H+-ATPase activity are summarized in relation to previous criticisms of these methods.Abbreviations DTT
dithiothreitol
- EDTA
ethylene diaminetetraacetic acid
- GP
B-glycerophosphate
- PCMBS
p-chloromercuribenzene sulphonic acid
- PMSF
phenylmethylsulphonyl fluoride 相似文献
126.
B. Sinha R. M. Singh U. P. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,82(4):399-404
Summary Studies on the genetics of leaf blight caused byAlternaria triticina using generation mean analysis revealed that additive components played a major role, but that dominance components also contributed significantly in controlling the variability for leaf blight resistance in wheat crosses. Furthermore, the additive x additive type of epistasis was predominant in the first three crosses, whereas in the fourth cross additive x dominance (j) and dominance x dominance (1) components of epistasis were most significant. Because of this it may be desirable to follow a simple recurrent selection scheme for higher tolerance, to isolate resistant plants from the segregating populations derived from crosses of parents of diverse origin following the pedigree method of breeding. CPAN-1887 was very tolerant to leaf blight in the present study and should be utilized in hybridization programs to develop leaf-blight-resistant varieties. 相似文献
127.
A total of 436 embryos/unfertilized ova was collected from 30 foot-and-mouth disease (FMD) viremic cattle; 106 of these embryos/ova were from eight donors that had FMD virus in their reproductive tracts. The 436 embryos/ova were washed and then either assayed in cell culture or intradermally in steer tongues or transferred to recipients. Foot-and-mouth infectivity was not found to be associated with any of the embryos/ova assayed in cell culture or intradermally. The 149 embryos transferred produced two abortions, five sets of twins born prematurely, and 15 normal calves. All of the recipients and all of the calves remained FMD-seronegative. 相似文献
128.
Summary
Fusarium oxysporum 841 produces a mixture of ethanol and acetic acid from glucose, xylose or Avicel (microcrystalline cellulose) substrates. Some metabolic inhibitors viz. sodium azide, dinitrophenol and polyethylene glycol were used for shifting product formation from acetic acid to ethanol. Using these inhibitors 1.5- to 2- fold increase in ethanol production was achieved with significant repression (by 80 to 90%) of acetic acid. Almost theoretical yields of ethanol were obtained. 相似文献
129.
Methylammonium/ammonium ion, glutamine, glutamate, arginine and proline uptake, and their assimilation as nitrogen sources, was studied in Nostoc muscorum and its glutamine synthetase-deficient mutant. Glutamine served as nitrogen source independent of glutamine synthetase activity. Glutamate was not metabolised as a nitrogen source but still inhibited nitrogenase activity and diazotrophic growth. Glutamine synthetase activity was essential for the assimilation of N2, ammonia, arginine and proline as nitrogen sources but not for the control of their transport, heterocyst formation, and production of ammonia or aminoacid dependent repressor signal for N2-fixing heterocysts. These results also suggest that glutamine synthetase serves as the sole route of ammonia assimilation and glutamine synthesis, and ammonia per se as the repressor signal for N2-fixing heterocysts and methylammonium (ammonium) transport. 相似文献
130.
V. Johnson M. Singh V. S. Saini V. R. Sista N. K. Yadav 《World journal of microbiology & biotechnology》1992,8(4):382-384
Maximum lipid production (66% w/w dry wt) inRhodotorula glutinis IIP-30 utilizing glucose in a fed-batch fermentation under N-limiting conditions at 30°C, was at pH 4. At pH 3, 5 and 6, the lipid contents were 12%, 48% and 44%, respectively. There was only a small change in the fatty acid profile over the pH range examined, although the ergosterol content decreased by a third as the pH increased. 相似文献