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61.
The application of the synthetic auxin 3,5,6-trichloro-2-piridyloxyacetic acid (3,5,6-TPA) isopropyl ester at the onset of
cell enlargement stage, significantly thinned fruitlets in ‘Clausellina’ Satsuma mandarin. The magnitude of the response was
related to the concentration applied, increasing the percentage of abscised fruit with higher concentrations, which was up
to 70% at 25 mg l−1. The magnitude of the response also depended on the organ subject to treatment, abscission being greater when applied to
the leaves rather than to fruit. Results suggest that a photosynthetic disorder was responsible for a reduction in fruit growth
rate, triggering abscission mechanisms producing ethylene and abscission. 相似文献
62.
The citrus fruit proteome: insights into citrus fruit metabolism 总被引:1,自引:0,他引:1
Fruit development and ripening are key processes in the production of the phytonutrients that are essential for a balanced diet and for disease prevention. The pathways involved in these processes are unique to plants and vary between species. Climacteric fruit ripening, especially in tomato, has been extensively studied; yet, ripening of non-climacteric fruit is poorly understood. Although the different species share common pathways; developmental programs, physiological, anatomical, biochemical composition and structural differences must contribute to the operation of unique pathways, genes and proteins. Citrus has a non-climacteric fruit ripening behavior and has a unique anatomical fruit structure. For the last few years a citrus genome-wide ESTs project has been initiated and consists of 222,911 clones corresponding to 19,854 contigs and 37,138 singletons. Taking advantage of the citrus database we analyzed the citrus proteome. Using LC-MS/MS we analyzed soluble and enriched membrane fractions of mature citrus fruit to identify the proteome of fruit juice cells. We have identified ca. 1,400 proteins from these fractions by searching NCBI-nr (green plants) and citrus ESTs databases, classified these proteins according to their putative function and assigned function according to known biosynthetic pathways. 相似文献
63.
Choi IY Kim SJ Jeong HJ Park SH Song YS Lee JH Kang TH Park JH Hwang GS Lee EJ Hong SH Kim HM Um JY 《Molecular and cellular biochemistry》2007,305(1-2):153-161
The citrus unshiu peel has been used traditionally as a medicine to improve bronchial and asthmatic conditions or cardiac
and blood circulation in Korea, China, and Japan. Here, we report the effects of citrus unshiu peel water extract (CPWE) on
the phorbol myristate acetate (PMA) + calcium ionophore A23187-induced hypoxia-inducible factor-1α (HIF-1α) activation and
inflammatory cytokine production from the human mast cell line, HMC-1 cells. We compared CPWE with hesperidin, a common constituent
of citrus unshiu. CPWE and hesperidin inhibited the PMA + A23187-induced HIF-1α expression and the subsequent production of
vascular endothelial growth factor (VEGF). In addition, CPWE suppressed PMA + A23187-induced phosphorylation of the extracellular
signal-regulated kinase (ERK). We also show that the increased cytokines interleukin (IL)-1β, IL-8, and tumor necrosis factor
(TNF)-α level was significantly inhibited by treatment of CPWE or hesperidin. In the present study, we report that CPWE and
hesperidin are inhibitors of HIF-1α and cytokines on the mast cell-mediated inflammatory responses. 相似文献
64.
The Basidiomycotine fungi Meira geulakonigii, Meira argovae and Acaromyces ingoldii were assayed in the laboratory against five species of herbivorous mites: Phyllocoptruta oleivora (Eriophyidae), Panonychus
citri, Eutetranychus
orientalis, Tetranychus
urticae and Tetranychus
cinnabarinus (all four Tetranychidae). All fungi caused significantly high mortality rates (as compared to controls) after 14 days, some
after 1 week. Phyllocoptruta oleivora was the most susceptible, showing >80% mortality even after 1 week. In a field trial, grapefruits sprayed either once a month
or once a season with M. geulakonigii had significantly fewer P. oleivora and less damage than unsprayed fruit. These results suggest that M. geulakonigii may protect grapefruits against the injurious P. oleivora. 相似文献
65.
Hirsutella thompsonii Fisher is a host-specific fungal pathogen of the diverse group of arthropods known as the Acari. It particularly affects
eriophyid mites, and the identification of its isolates is a difficult task due to its pleomorphic nature. Seven isolates
of H. thompsonii var. thompsonii and H. thompsonii var. synnematosa collected from various agro-climatic regions of India were subjected to PCR analysis using random decamer primers to differentiate
between them. Random amplified polymorphic DNA analysis revealed that all of the isolates from the citrus rust mite, Phyllocoptruta oleivora Ashmead (Acari: Eriophyidae), clustered together, with the exception of one, HtCRMB. The only isolate of H. thompsonii from Aceria guerreronis keifer (Acari: Eriophydae), HtPDBC, clustered separately. 相似文献
66.
67.
Neng-Guo Tao Juan Xu Yun-Jiang Cheng Xiu-Xin Deng 《植物学报(英文版)》2006,48(3):315-319
A cDNA library was constructed end characterized from the pulp of Cera Care navel orange (Citrus sinensis Osbeck) at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke (MT) gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng. 相似文献
68.
‘沙田’柚果生长期套袋对果实品质的影响 总被引:2,自引:0,他引:2
‘沙田’柚果生长期进行套袋,是提高果实品质的有效措施之一。在田间生长条件下,研究了套袋对‘沙田’柚果实品质的影响。结果表明,套袋促进了柚果生长发育,提高了商品率,降低了含酸量,较明显地提高其糖酸比,并增加了维生素C的含量,从而提高了柚果品质。 相似文献
69.
J. P. Bonani A. Fereres E. Garzo M. P. Miranda B. Appezzato-Da-Gloria & J. R. S. Lopes 《Entomologia Experimentalis et Applicata》2010,134(1):35-49
Detailed information on probing behavior of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is critical for understanding the transmission process of phloem‐limited bacteria (Candidatus Liberibacter spp.) associated with citrus ‘huanglongbing’ by this vector. In this study, we investigated stylet penetration activities of D. citri on seedlings of Citrus sinensis (L.) Osbeck cv. Pêra (Rutaceae) by using the electrical penetration graph (EPG‐DC system) technique. EPG waveforms were described based on amplitude, frequency, voltage level, and electrical origin of the observed traces during stylet penetration into plant tissues. The main waveforms were correlated with histological observations of salivary sheath termini in plant tissues, to determine the putative location of stylet tips. The behavioral activities were also inferred based on waveform similarities in relation to other Sternorrhyncha, particularly aphids and whiteflies. In addition, we correlated the occurrence of specific waveforms with the acquisition of the phloem‐limited bacterium Ca. Liberibacter asiaticus by D. citri. The occurrence of a G‐like xylem sap ingestion waveform in starved and unstarved psyllids was also compared. By analyzing 8‐h EPGs of adult females, five waveforms were described: (C) salivary sheath secretion and other stylet pathway activities; (D) first contact with phloem (distinct from other waveforms reported for Sternorrhyncha); (E1) putative salivation in phloem sieve tubes; (E2) phloem sap ingestion; and (G) probably xylem sap ingestion. Diaphorina citri initiates a probe with stylet pathway through epidermis and parenchyma (C). Interestingly, no potential drops were observed during the stylet pathway phase, as are usually recorded in aphids and other Sternorrhyncha. Once in C, D. citri shows a higher propensity to return to non‐probing than to start a phloem or xylem phase. Several probes are usually observed before the phloem phase; waveform D is observed upon phloem contact, always immediately followed by E1. After E1, D. citri either returns to pathway activity (C) or starts phloem sap ingestion, which was the longest activity observed. 相似文献
70.
Jerry Mozoruk Laura E. Hunnicutt Ronald D. Cave Wayne B. Hunter Michael G. Bausher 《Plant science》2006,170(6):1068-1080