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1.
Rouhollah Karimi Abdolhossein Rezaei Nejad Shahrokh Khanizadeh 《The Journal of Horticultural Science and Biotechnology》2016,91(4):386-395
The effects of exogenous application of abscisic acid (ABA) on anti-oxidant enzyme activities and photosynthetic capacity in ‘Sultana’ grapevine (Vitis vinifera L.) were investigated under cold stress. When vines had an average of 15 leaves, 0 (control), 50, 100, or 200 µM ABA was sprayed to run-off on all leaves of each plant. Twenty-four hours after foliar spraying with ABA, half (n = 5) of the water-only control vines and half (n = 5) of each group of ABA-treated plants were subjected to 4°C for 12 h, followed by a recovery period of 3 d under greenhouse conditions (25°/18°C day/night). The remaining plants in each treatment group were kept at 24°C. Cold stress increased H2O2 and malondialdehyde (MDA) concentrations in vine leaves, whereas all foliar ABA treatments significantly reduced their levels. Chilled plants showed marked increases in their total soluble protein contents in response to each ABA treatment. ABA significantly increased the activities of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in cold-stressed grapevine leaves. In contrast, cold stress markedly decreased the rates of leaf photosynthesis (A) and evaporation (E), stomatal conductance (gs), and chlorophyll concentrations in leaves, but increased intercellular CO2 concentrations (Ci) in leaves. Treatment with all concentrations of ABA resulted in lower leaf A, E, and gs values, but higher Ci values at 24°C. However, following cold stress, ABA-treated vines showed higher leaf A, E, and gs values, but lower Ci values compared to control vines without ABA treatment. The application of 50–200 µM ABA allowed chilled vines to recover more quickly when re-exposed to normal temperatures, enabling the vines to resume their photosynthetic capacity more efficiently following cold stress. These results showed that, by stimulating anti-oxidant enzyme systems and alleviating cold-induced stomatal limitations, ABA reduced the inhibitory effect of cold stress on the rate of CO2 fixation in ‘Sultana’ grapevine plants. 相似文献
2.
We analyzed the structure of pollarded oak forest and biometric indices of pollarded oak species in relation to aspect in northern Zagros forests, western Iran. A number of 319 circular plots (0.1 ha) were established using a systematic random method over the study area. In each plot, for all trees (diameter at breast height ≥5 cm) diameter was measured and tree species was recorded. Total height, trunk height, and major and minor diameter axis of the crown of two trees in each plot (nearest tree to the center of the plot and the largest tree in term of diameter) were measured. As the dispersion of slope and altitude classes in the study area were identical, the effect of these factors was assumed to be constant. To evaluate the effect of aspect on biometric indices of oak trees a comparison was used for each oak species separately. The results indicated that the forest species composition differed statistically significant in main aspects except for easterly and westerly aspects (P < 0.01). The diameter of similar oak trees was significantly different except for Lebanon oak in northerly and southerly and Gall oak in easterly and westerly aspects (P < 0.01), but there was no significant difference between the total height and crown area of similar oak species in different aspects. Differences in diameter, height, and crown area distributions showed a significant difference in main aspects. The basal area and tree density in northerly and southerly aspects were significantly different (P < 0.05). 相似文献
3.
Fardin Hamedi Shahrokh Fatehi 《Communications in Soil Science and Plant Analysis》2017,48(19):2324-2337
This study investigated phosphorus (P) dynamics and kinetics in calcareous soil under inorganic, organic, and integrated (inorganic+organic) fertilizer systems during two growing seasons of maize in two soil depths (0–0.15 and 0.15–0.30 m). A field experiment was conducted with 150, 300, and 400 kg ha?1 triple superphosphate (TSP), 7.5 and 15.0 ton ha?1 (on dry matter basis) farmyard manure (FYM), and integrated systems. In order to analyze Olsen P, soil samples were collected in 30-day-intervals after planting. The results showed that at the end of the two growing seasons of maize, the lowest magnitudes of Olsen P0–0.15 m were 6.0, 6.8, 7.4, and 7.6 mg kg?1 for the control, 7.5 FYM, 15 FYM, and 150 TSP, respectively. The highest magnitudes of Olsen P0–0.15 m were 12.4, 11.5, 11.4, and 11.1 mg kg?1 for 300 TSP+15 FYM, 400 TSP+7.5 FYM, 400 TSP+15 FYM, and 300 TSP+7.5 FYM, respectively. The same trends were observed for Olsen P0.15–0.30 m. Heterogeneous diffusion model demonstrated that Elovich equation could best describe the experimental data (mean; R2 = 0.98, SE = 0.29). The highest P supply rates (PSR) were 4.73, 3.91, and 3.86 mg kg?1day?1 (days after application) for 400 TSP, 400 TSP+15 FYM, and 300 TSP, respectively. The models of P supply capacity of soil could estimate P supply of soil under different fertilizer systems (R2 = 0.84–0.95). The present study improved the understanding of the capacity and rate of P supply by considering P uptake by grain maize. Fertilizer recommendations depend on the accessibility of fertilizer types suggested to help choose the best fertilizer systems. 相似文献
4.
Journal of Plant Diseases and Protection - Remote detection of aerial parasitic plants in forests is imperative in precision forestry, as it can help to manage tree stands and to monitor forest... 相似文献
5.
Attempts to design species‐specific PCR primers from six European Armillaria species in the ribosomal RNA genes are reported. Primers were developed on the basis of the nucleotide sequence variability of the internal transcribed spacers (ITS) and the intergenic spacer (IGS1) of the ribosomal DNA. Four sets of primers gave specific PCR products for Armillaria tabescens, Armillaria mellea and Armillaria ostoyae. However, due to the high sequence similarities between Armillaria borealis and Armillaria ostoyae and between Armillaria cepistipes and Armillaria gallica no species specific amplification was obtained for these taxa. 相似文献
6.
[目的]通过克隆‘砀山酥梨’(Pyrus bretschneideri ‘Dangshansuli’)果实中咖啡酰-辅酶AO-甲基转移酶(CCoAOMT)基因的全长序列,并对其进行生物信息学及基因表达差异分析,阐释了其在梨果实木质素合成途径的作用,以期为今后利用基因调控技术来改变果实中石细胞含量从而改善梨果实品质提供一定的理论依据。[方法]以15年生‘砀山酥梨’果实为试材,根据从NCBI数据库中搜索得到关于植物木质化的CCoAOMT基因序列与梨基因组数据库调取的序列比对,利用RT-PCR技术克隆得到了木质素生物合成途径中的一种关键酶基因PbCCoAOMT,GenBank登录号为KJ577544。[结果]该基因全长1133bp,具有1个744bp的完整开放阅读框(ORF),编码247个氨基酸。序列比对及系统进化树分析表明:CCoAOMT酶是氧甲基转移酶类,与其他植物CCoAOMT编码的蛋白序列有较高的相似性,尤其与枇杷的相似度最高,达到98.79%,且亲缘关系最近。利用荧光定量PCR技术对其在果实不同发育时期表达模式的分析发现,基因表达量呈先上升后下降的趋势,与梨果实中石细胞含量的变化趋势相似。[结论]初步认为从‘砀山酥梨’中克隆得到的PbCCoAOMT基因可能参与了梨果实中木质素的代谢。 相似文献
7.
Inga Moročko-Bičevska Jamshid Fatehi 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(4):567-577
Gnomonia fragariae is a poorly studied ascomycete, which was recently demonstrated to be a cause of severe root rot and petiole blight of strawberry.
The pathogen was genetically transformed with the GFP as a vital marker and hygromycin resistance gene. Several stable transformants
were obtained, which did not differ in their phenotype from the wild type isolate. Using one of the GFP-tagged isolates the
infection process and colonization of roots and petioles of host plant by the pathogen were studied. Fluorescence microscopy
examinations of the inoculated plants at different time points showed that plant infection occurs 24 h after inoculation and
intensively continues during first 3 days. The specific penetration sites on epidermal cells and preferences in colonization
for certain root and petiole tissues were observed. The pathogen intensively colonized and destroyed cortex of roots and petioles
and spread rapidly longitudinally within intercellular spaces. The petioles were colonized by the hyphae, which grew mostly
in the intracellular spaces of the cortical cells while in the roots the intracellular growth of hyphae occurred only in the
later stages of infection. The fungus was also capable to infect the vascular tissues of petioles although these were not
the primary tissues colonized by the pathogen. The mature ascomata were formed on the infected petiole bases several weeks
after the inoculation. This study presents a genetic transformation method for Gnomonia fragariae and it demonstrates details on infection process and colonization of root, crown and petiole tissues of strawberry by the
pathogen. 相似文献
8.
树莓的货架期很短,因此选育货架期长的品种是扩大树莓鲜食市场经济而有效的方法。试验通过测定不同品系树莓果实产量,并对与货架期相关的果实品质进行分析,对不同树莓品系进行了综合评价。结果表明,树莓果实坚硬度是鲜食品种的最重要性状之一,供试品系的果实坚硬度、果实可溶物含量、果实渗漏性、汁液损失、果实抗腐性以及在果实适销性等方面都优于对照品种的相应指标。特别是在4℃条件下,SJR944—2,SJR942—7和SJR941—5有较长的货架期品质。 相似文献
9.
肉桂醇脱氢酶(CAD)是木质素生物合成过程中的一个关键酶。本研究分别提取了"砀山酥梨"及"幸水"梨果肉总RNA,并通过RT-PCR、克隆和测序,成功获得了2个CAD的大小为689bp的cDNA片段,并分别命名为PB-CAD(登录号:FJ478151)和PP-CAD(登录号:FJ478152)。在核苷酸水平上,这两个基因片段只有4个碱基的差异,编码相似性达99.6%的两个氨基酸序列,该序列由229个残基组成。通过蛋白质序列比较,发现梨果实CAD与许多植物中CAD氨基酸序列极为相似,与苹果Malus domestica(AAC06319)、梅Prunus mume(BAE48658)、枇杷Eriobotryajaponica(ABV44810)和葡萄Vitis vinifera(CAO21890)的相似性分别达到97.8%、95%、92.6%和83.4%。 相似文献
10.
Mehdi Azari Mojtaba Kafi Bita Ebrahimi Roya Fatehi Mahboobeh Jamalzadeh 《Veterinary research communications》2017,41(1):49-56