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1.
Rengel, Z. and Kordan, H. A. 1987. Effects of growth regulators on light-dependent anthocyanin production in Zea mays seedlings.
The effects of ethylene, indolyl- and naphthylacetic acids, zeatin, benzyladenine, gib-berellic acid and triiodobenzoic acid on anthocyanin production in seedlings of Zea mays L. cv. Golden Bantam were investigated. Endogenously produced and exogen-ously supplied ethylene, as well as the other growth regulators tested markedly suppressed anthocyanin formation. Except for triiodobenzoic acid, the other growth regulators stimulated ethylene production, the amounts produced in the light being larger than those in the dark. Absorption of ethylene by permanganate as well as inhibition of ethylene production or action by Co2+ or Ag+ increased anthocyanin formation in maize seedlings above the level found in the control plants. The inhibiting effect of auxins and cytokinins on anthocyanin production was reversed by Co2+ or Ag+ . In contrast, decreased anthocyanin formation caused by gibberellic acid or triiodobenzoic acid seemed unrelated to ethylene and could not be alleviated by Co2+ or Ag+. 相似文献
The effects of ethylene, indolyl- and naphthylacetic acids, zeatin, benzyladenine, gib-berellic acid and triiodobenzoic acid on anthocyanin production in seedlings of Zea mays L. cv. Golden Bantam were investigated. Endogenously produced and exogen-ously supplied ethylene, as well as the other growth regulators tested markedly suppressed anthocyanin formation. Except for triiodobenzoic acid, the other growth regulators stimulated ethylene production, the amounts produced in the light being larger than those in the dark. Absorption of ethylene by permanganate as well as inhibition of ethylene production or action by Co
2.
A crown rot disease in wheat caused by the fungusFusarium graminearum Schw. Group 1 is a widespread problem in chronically Zn-deficient Australian soils. A link between crown rot and Zn deficiency
was established by Sparrow and Graham (1988). This paper reports a test of a further hypothesis, that wheat genotypes more
efficient at extracting zinc from low-zinc soils are more resistant to infection by this pathogen. Three wheat cultivars (Excalibur,
Songlen and Durati) of differential Zn efficiency were tested at three zinc levels (0.05, 0.5 and 2.0 mg Zn kg−1 of soil) and three levels ofF. graminearum S. Group 1 inoculum (0.1 g and 0.3 g kg−1 live chaff-inoculum and control having 0.1 g kg−1 dead chaff inoculum). Six weeks after sowing dry matter production of shoots and roots was decreased byFusarium inoculation at 0.05 mg and 0.5 mg kg−1 applied Zn.Fusarium inoculum at 0.1 g was as effective as 0.3 g kg−1 for infection and decreasing dry matter. The infection at the basal part of culm decreased significantly by increasing the
rate of Zn application. Excalibur, a Zn-efficient cultivar (tolerant to Zn deficiency) produced significantly more shoot and
root dry matter, and showed less disease infection compared with Zn-inefficient cultivars (Durati and Songlen) at low (0.05
mg Zn kg−1 soil) and medium (0.5 mg Zn kg−1 soil) Zn fertilization rates. Higher rate of Zn fertilization (2.0 mg Zn kg−1 soil) reduced the disease level in Durati to the level of Excalibur but the disease level of Songlen was still high, indicating
its high Zn requirement and or sensitivity to crown rot. The data on Zn uptake show that Excalibur, being Zn-efficient, was
able to scavenge enough Zn from Zn-deficient soil, we suggest that besides sustaining growth Excalibur was able to build and
maintain resistance to the pathogen; inefficient cultivars needed extra Zn fertilization to achieve performance comparable
to that of Excalibur. The present study indicates that growing Zn-efficient cultivars of wheat along with judicious use of
Zn fertilizer in Zn-deficient areas where crown rot is a problem may sustain wheat production by reducing the severity of
the disease as well as by increasing the plant vigour through improved Zn nutrition. ei]Section editor: R Rodriques-Kalana 相似文献
3.
Inhibition of lignin biosynthesis in Triticum aestivum L. rootsby Mn deficiency has been suggested as the mechanism of reducedresistance of Mn-deficient wheat roots to infection by the take-allfungus (Gaeumannomyces graminis var. tritici). This study evaluatedphenolics and lignin accumulation in roots of wheat genotypesdiffering in Mn efficiency (measured as growth and yield inMn-deficient soils) and take-all resistance. Seedlings of theMn-inefficient, take-all sensitive genotype Bayonet and theMn-efficient, more take-all resistant genotype C8MM were grownin nutrient solution without added Mn for 18 d and then transferredto a Mn-deficient sandy soil fertilized with Mn at 0 or 30 mgkg-1. Both genotypes had Mn-deficient roots and shoots at thetime of transfer to the soil. Roots of both genotypes were inoculatedwith the take-all fungus 0, 1, 3 and 7 d after transfer. Twenty-fourhours after inoculation, take-all fungus penetrated the rootstele of take-all sensitive Bayonet but not of more resistantC8MM wheat. Rates of phenolics and lignin accumulation in rootsdeclined steadily during growth in soil for up to 8 d, werehigher in mature, fully differentiated parts of the root systemcompared to distal, younger root tissue, and were higher inBayonet than in C8MM. Manganese fertilization did not significantlyinfluence rates of phenolics and lignin accumulation but reduceddepth of radial penetration by hyphae in both genotypes. Therate of phenolics accumulation was positively (r = 0·91to 0·96) correlated with the rate of lignin accumulation.Mn-efficient C8MM had a higher rate of lignin accumulation perunit of phenolics than Mn-inefficient Bayonet over a wide rangeof phenolics synthesis rates. From this we suggest that C8MMhas a more efficient mechanism for conversion of phenolics tolignin, the trait which appears related to higher take-all resistanceof this genotype.Copyright 1994, 1999 Academic Press Gaeumannomyces graminis var. tritici, lignin, manganese, phenolics, resistance, roots, Triticum aestivum 相似文献
4.
Eggplants (Solanum melongena L. cv. Bonica) were grown in a glasshouse during summer under natural light with one unbranched shoot or one shoot with 3
to 4 branches and with or without fruit in quartz sand buffered and not buffered with 0.5% CaCO3 (w : v), respectively. Nutrient solutions supplied contained nitrate or ammonium as the sole nitrogen source.
Compared with nutrient solutions containing nitrate (10 mM), solutions containing ammonium (10 mM) caused a decrease in net photosynthesis of eggplants during early stages of vegetative growth when grown in quartz sand
not buffered with CaCO3. The decrease was not observed before leaves showed interveinal chlorosis. In contrast, net photosynthesis after bloom at
first increased more rapidly in eggplants supplied with ammonium than with nitrate nitrogen. However, even in this case, net
photosynthesis decreased four weeks later when ammonium nutrition was continued. The decrease was accompanied by epinasty
and interveinal chlorosis on the lower leaves and later by severe wilting, leaf drop, stem lesions, and hampered growth of
stems, roots, and fruits. These symptoms appeared later on plants not bearing fruits than on plants bearing fruits. If nutrient
solutions containing increasing concentrations of ammonium (0.5–30 mM) were supplied after the time of first fruit ripening, shoot growth and set of later flowers and fruits were promoted. In
contrast, vegetative growth and reproduction was only slightly affected by increasing the concentration of nitrate in the
nutrient solutions.
In quartz sand buffered with CaCO3 ammonium nutrition caused deleterious effects only under low light conditions (shade) and on young plants during rapid fruit
growth. If eggplants were supplied with ammonium nitrogen before bloom, vegetative growth was promoted, and set of flowers
and fruit occurred earlier than on plants supplied with nitrate. Furthermore, the number of flowers and fruit yield increased.
These effects of ammonium nutrition were more pronounced when plants were grown with branched shoots than with unbranched
shoots.
The results indicate that vegetative and reproductive growth of eggplants may be manipulated without causing injury to the
plants by supplying ammonium nitrogen as long as the age of the plants, carbohydrate reserves of the roots, quantity of ammonium
nitrogen supplied, and pH of the growth medium are favourable. T W Rufty Section editor 相似文献
5.
Chickpea facilitates phosphorus uptake by intercropped wheat from an organic phosphorus source 总被引:7,自引:1,他引:7
Pot experiments were conducted to investigate interspecific complementation in utilization of phytate and FePO4 by plants in the wheat (Triticum aestivum L.)/chickpea (Cicer arietinum L.) intercropping under sterile and non-sterile conditions. The pots were separated into two compartments by either a solid root barrier to eliminate root contact and solute movement, by a nylon mesh (30 M) to prevent root contact but permit solute exchange, or not separated between the compartments. Wheat plants were grown in one compartment and chickpea in the other. Two P sources were tested at 60 mg P kg–1 soil (sodium phytate or FePO4). Under non-sterile conditions, the biomass of wheat was significantly greater when the roots were intermingled with chickpea than when the roots were separated from chickpea roots by a solid root barrier or nylon mesh. When phytate–P was applied, P concentrations in wheat (2.9 g kg–1 in shoots and 1.4 g kg–1 in roots) without root barrier between the two species were higher than those in the treatments with nylon mesh or with the solid root barrier separation (1.9 g kg–1 in shoots and 1.0 g kg–1 in roots). In contrast, P concentrations in wheat supplied with FePO4 were similar between the root separation treatments. There was no significant difference in P uptake by chickpea between the P sources or between the root separation treatments, except that P uptake was greater in the phytate treatment with the root barrier. Total P uptake from phytate was increased by 25% without root separation compared to the root separation treatments. Under sterile conditions and supply of phytate–P, the biomass of wheat was doubled when the roots were intermingled with chickpea and increased by a third with the nylon mesh separation compared to that with the solid root barrier. Biomass production in wheat at various treatments correlated with P concentration in shoot. Biomass production and P concentration in chickpea were unaffected by root separation. Total P uptake by plants was 68% greater with root intermingling and 37% greater with nylon mesh separation than that with the solid root barrier. The results suggest that chickpea roots facilitate P utilization from the organic P by wheat. 相似文献
6.
7.
Arunagiri Kuha Deva Magendhra Rao Vittal Rangan Arvinden Deepa Ramasamy Krishna Patel Balaiah Meenakumari Priya Ramanathan Shirley Sundersingh Velusami Sridevi Thangarajan Rajkumar Zdenko Herceg Harsha Gowda Samson Mani 《Journal of cellular and molecular medicine》2021,25(8):3912-3921
Breast cancer is a major cause of cancer-related death in women worldwide. Non-coding RNAs are a potential resource to be used as an early diagnostic biomarker for breast cancer. Circular RNAs are a recently identified group of non-coding RNA with a significant role in disease development with potential utility in diagnosis/prognosis in cancer. In this study, we identified 26 differentially expressed circular RNAs associated with early-stage breast cancer. RNA sequencing and two circRNA detection tools (find_circ and DCC) were used to understand the circRNA expression signature in breast cancer. We identified hsa_circ_0006743 (circJMJD1C) and hsa_circ_0002496 (circAPPBP1) to be significantly up-regulated in early-stage breast cancer tissues. Co-expression analysis identified four pairs of circRNA-miRNA (hsa_circ_0023990 : hsa-miR-548b-3p, hsa_circ_0016601 : hsa_miR-1246, hsa_circ_0001946 : hsa-miR-1299 and hsa_circ_0000117:hsa-miR-502-5p) having potential interaction. The miRNA target prediction and network analysis revealed mRNA possibly regulated by circRNAs. We have thus identified circRNAs of diagnostic implications in breast cancer and also observed circRNA-miRNA interaction which could be involved in breast cancer development. 相似文献
8.
To counteract the adverse effects of various DNA lesions, cells have evolved an array of diverse repair pathways to restore DNA structure and to coordinate repair with cell cycle regulation. Chromatin changes are an integral part of the DNA damage response, particularly with regard to the types of repair that involve assembly of large multiprotein complexes such as those involved in double strand break (DSB) repair and nucleotide excision repair (NER). A number of phosphorylation, acetylation, methylation, ubiquitylation and chromatin remodeling events modulate chromatin structure at the lesion site. These changes demarcate chromatin neighboring the lesion, afford accessibility and binding surfaces to repair factors and provide on-the-spot means to coordinate repair and damage signaling. Thus, the hierarchical assembly of repair factors at a double strand break is mostly due to their regulated interactions with posttranslational modifications of histones. A large number of chromatin remodelers are required at different stages of DSB repair and NER. Remodelers physically interact with proteins involved in repair processes, suggesting that chromatin remodeling is a requisite for repair factors to access the damaged site. Together, recent findings define the roles of histone post-translational modifications and chromatin remodeling in the DNA damage response and underscore possible differences in the requirements for these events in relation to the chromatin context. 相似文献
9.
Lucia Vernerova Frantisek Spoutil Miroslav Vlcek Katarina Krskova Adela Penesova Milada Meskova Andrea Marko Katarina Raslova Branislav Vohnout Jozef Rovensky Zdenko Killinger Ivana Jochmanova Ivica Lazurova Guenter Steiner Josef Smolen Richard Imrich 《PloS one》2016,11(4)
IntroductionThe aim of the study was to analyse genetic architecture of RA by utilizing multiparametric statistical methods such as linear discriminant analysis (LDA) and redundancy analysis (RDA).MethodsA total of 1393 volunteers, 499 patients with RA and 894 healthy controls were included in the study. The presence of shared epitope (SE) in HLA-DRB1 and 11 SNPs (PTPN22 C/T (rs2476601), STAT4 G/T (rs7574865), CTLA4 A/G (rs3087243), TRAF1/C5 A/G (rs3761847), IRF5 T/C (rs10488631), TNFAIP3 C/T (rs5029937), AFF3 A/T (rs11676922), PADI4 C/T (rs2240340), CD28 T/C (rs1980422), CSK G/A (rs34933034) and FCGR3A A/C (rs396991), rheumatoid factor (RF), anti–citrullinated protein antibodies (ACPA) and clinical status was analysed using the LDA and RDA.ResultsHLA-DRB1, PTPN22, STAT4, IRF5 and PADI4 significantly discriminated between RA patients and healthy controls in LDA. The correlation between RA diagnosis and the explanatory variables in the model was 0.328 (Trace = 0.107; F = 13.715; P = 0.0002). The risk variants of IRF5 and CD28 genes were found to be common determinants for seropositivity in RDA, while positivity of RF alone was associated with the CTLA4 risk variant in heterozygous form. The correlation between serologic status and genetic determinants on the 1st ordinal axis was 0.468, and 0.145 on the 2nd one (Trace = 0.179; F = 6.135; P = 0.001). The risk alleles in AFF3 gene together with the presence of ACPA were associated with higher clinical severity of RA.ConclusionsThe association among multiple risk variants related to T cell receptor signalling with seropositivity may play an important role in distinct clinical phenotypes of RA. Our study demonstrates that multiparametric analyses represent a powerful tool for investigation of mutual relationships of potential risk factors in complex diseases such as RA. 相似文献
10.