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1.
Indian jujube (Ziziphus mauritiana Lamk.) has been recognised as an underutilised plant worthy of further research and development by the Indian National Genetic Resources Programme and the International Centre for Underutilised Crops, UK. It is an important fruit crop of the hot arid regions in India as it forms an integral part of the life of the locals as a source of nutrition, fodder (leaves), fuel (pruned wood) and it has several ethnobotanical uses. In this study, 8 of the 10 principal growth stages based on the existing Biologische Bundesantalt, Bundessortenamt und Chemische Industrie (BBCH) scale were used to describe Indian jujube. These growth stages were vegetative bud development (Stage 0), leaf development (Stage 1), shoot development (Stage 3), inflorescence development (Stage 5), flower development (Stage 6), fruit development (Stage 7), fruit maturity (Stage 8) and senescence or beginning of dormancy (Stage 9). The phenological BBCH scale for Indian jujube can be used to guide the growers as to when to carry out orchard management practices such as canopy training and pruning, nutrient and water application, pest and disease control and post‐harvest processing.  相似文献   

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An experiment was conducted to study the effect of NaCl (electric conductivity of 0, 4, 8, 12, and 16 dS m?1) on growth, gas exchange parameters, water status, membrane injury, chlorophyll stability index and oxidative defense mechanisms in two cultivars (Gola and Umran) of Indian jujube (Ziziphus mauritiana). Results showed that the dry mass and leaf area reduced linearly with increasing levels of salinity. Net photosynthetic rate (P N), transpiration (E), and stomatal conductance (g s) were comparatively lower in Umran which further declined with salinity. Leaf relative water content, chlorophyll (Chl) stability and membrane stability also decreased significantly under salt stress, with higher magnitude in Umran. Superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) activities were higher in Gola whereas hydrogen peroxide (H2O2) accumulation and lipid peroxidation (MDA content) were higher in control as well as salttreated plants of Umran. The Na+ content was higher in the roots of Gola and in the leaves of Umran, resulting in high K+/Na+ ratio in Gola leaves. Thus it is suggested that salt tolerance mechanism is more efficiently operative in cultivar Gola owing to better management of growth, physiological attributes, antioxidative defense mechanism, and restricted translocation of Na+ from root to leaves along with larger accumulation of K+ in its leaves.  相似文献   

4.
The tropical fruit tree, Ziziphus mauritiana (Rhamnaceae), a native of the Indian subcontinent, is a pasture and environmental weed in northern Australia and Fiji. In their native range, Ziziphus spp., including commercially cultivated Z. mauritiana and Z. jujuba, are subjected to a wide range of pests and diseases. The feasibility of classical biological control of this weed has not been explored to date. Effective biological control could reduce plant vigour and seed output, thereby limiting the spread of Z. mauritiana in Australia. Two Ziziphus species are native to Australia, hence, any prospective biological control agent should be specific to Z. mauritiana. Opportunistic field surveys and literature searches identified 133 species of phytophagous insects, 9 species of phytophagous mites and 12 plant pathogens on Ziziphus spp. Host records suggest the following are possibly specific to Z. mauritiana and hence are prospective biological control agents in Australia: the seed‐feeding weevil Aubeus himalayanus; the leaf‐feeding gracillariid moth Phyllonorycter iochrysis; the leaf‐mining chrysomelid beetle Platypria erinaceus; the leaf‐folding crambid moth Synclera univocalis; the leaf‐galling midge Phyllodiplosis jujubae; and the gall‐mites Aceria cernuus and Larvacarus transitans. Host range of the rust Phakopsora zizyphi‐vulgaris includes many Ziziphus species, including the native Z. oenoplia and hence would not be a suitable biological control agent in Australia. The powdery mildew Pseudoidium ziziphi, with a host range restricted to Ziziphus species, has not been reported on Z. oenoplia. All available information on the pests and diseases of Z. mauritiana are from cultivated varieties. Hence, future surveys should focus on wild Z. mauritiana in the Indian subcontinent in areas that are climatically similar to the regions of northern Australia, where it is currently most abundant.  相似文献   

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The phenological growth stages of jujube tree are first described here using the BBCH scale. Based on this general scale, jujube phenology showed 8 of the 10 principal stages (0–9): bud, leaf and shoot development, inflorescence emergence, flowering, fruit development, fruit maturity and senescence. A schematic representation of the chronological progression of principal growth stages of jujube is also shown. The codification of the different growth stages is important for correct timing of general orchard management, particularly for disease and pest management. Besides, it will help farmers to efficiently schedule and manage jujube cultivation, as well as to improve knowledge dissemination among scientists around the World.  相似文献   

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Winter jujube, a species that originated in China, is the most prominent elite variety of jujube (Zizyphus jujuba Mill.). Due to its economic value and its recalcitrance to improvements through traditional plant breeding approaches, genetic transformation techniques may have a great potential in providing the means to transfer one or more selected desirable traits into the plant genome. We reported here an improved protocol for the Agrobacterium-mediated transformation of shoot tips of winter jujube. We have identified a set of optimum transformation conditions that take into account Agrobacterium inoculum density, Agrobacterium incubation period, co-cultivation conditions, and vacuum (use of a vacuum pump to create a negative-pressure environment). The highest transformation frequency (5.2%) was obtained when the shoot-tip explants were infected for 10 min and co-cultured for 4 days with Agrobacterium at OD600 0.8 under a negative pressure of 0.5 × 105 Pa. PCR and southern blot analyses confirmed the presence of transgenic plants and the stable integration of the target gene into the genome of regenerated plants. A histochemical staining analysis for GUS activity in the transgenic shoot tips also validated the efficiency of the transformation system.  相似文献   

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红枣贮藏期果面微生物多样性   总被引:2,自引:0,他引:2  
沙月霞 《生态学报》2011,31(2):483-490
以2种成熟度不同的红枣(Zizyphus jujuba Mill.)为试验材料在入库前采用保鲜剂处理,未采用保鲜剂处理的红枣为试验对照,研究红枣不同贮藏时期果面微生物多样性。结果表明:红枣贮藏期果面微生物种群中,细菌是优势类群,占微生物总数80%以上,真菌较少;采摘期红枣果面上就携带微生物,真菌优势菌株属于链格孢(Alternaria),其次为镰刀菌(Fusarium)和木霉(Trichoderma),贮藏期优势菌株属于链格孢(Alternaria)、青霉(Penicillium)、木霉(Trichoderma)和镰刀菌(Fusarium),曲霉(Aspergillus)、毛霉(Mucor)和根霉(Rhizopus)次之。红枣贮藏期果面微生物种群动态失衡是导致贮藏病害发生的主要原因,成熟度较高的红枣果面微生物总数、真菌和细菌的数量明显高于成熟度较低的红枣,使用保鲜剂后有效地降低了红枣贮藏期果面微生物的多样性,贮藏时间越长红枣果面微生物的多样性越明显。  相似文献   

8.
梨枣花果期耗水规律及其与茎直径变化的相关分析   总被引:3,自引:0,他引:3  
设置4个水分处理,研究了4年生梨枣2010年及2011年花果期不同供水条件下土壤水分动态和耗水规律,分析了梨枣日耗水量与茎直径变化间的相关性,建立回归模型.结果表明:(1)2a内各处理梨枣耗水量随土壤供水量的增加而增大,其日耗水量最大值均出现在灌水后1周内;各处理果实膨大期日耗水强度大于开花坐果期.(2)2a内各处理茎直径日变化平均值(MTD)、茎直径日最大值(MXTD)均符合Logistic函数关系,MXTD与MTD在表征梨枣茎秆生长规律方面效果一致,各处理茎直径变化指标(MTD、MXTD)增长率因水分处理的不同而存在差异.(3)高水分(T1处理)条件下茎直径变化指标(MTD、MXTD、MDS(茎直径日最大收缩量)、DG(茎直径日生长量))在表征枣树耗水状况方面不敏感;在低水分(T4处理)条件下,日耗水量与茎直径日最大收缩量(MDS)相关系数较其他3个茎直径变化指标(MTD、MXTD、DG)高且达极显著水平,说明MDS能够更好的表征低水分处理的梨枣耗水规律.在此基础上建立耗水量与茎直径变化回归模型,为评价梨枣耗水状况提供依据.  相似文献   

9.
The main objective of this study was to investigate the potential of peanut husk (Arachis hypogaea L.) as a fiber–peanut mixture to produce fiberboards for general purposes. For panel production, the addition of peanut husk at various percentages to the wood fiber was the only variable. Panels produced utilizing peanut husk were compared to panels produced using 100% wood fiber. The chemical properties of peanut husk; holocellulose and lignin content, alcohol–benzene, hot and cold water, and dilute alkali (1% NaOH) solubility, were also determined. Results indicated that panels could be produced utilizing up to 30% peanut husk without affecting the usability of the panels. It was not possible to meet the minimum IB strength standards when peanut husk was added to the mixture. Higher additions resulted in panels having lower elastic and rupture moduli than the minimum requirements according to TS-EN standards.  相似文献   

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The glenohumeral joint is the most frequently dislocated major joint in the body, and instability due to permanent deformation of the glenohumeral capsule is a common pathology. The corresponding change in mechanical properties may have implications for the ideal location and extent of plication, which is a common clinical procedure used to repair the capsule. Therefore, the objective of this study was to quantify the mechanical properties of four regions of the glenohumeral capsule after anterior dislocation and compare the properties to the normal glenohumeral capsule. Six fresh-frozen cadaveric shoulders were dislocated in the anterior direction with the joint in the apprehension position using a robotic testing system. After dislocation, mechanical testing was performed on the injured glenohumeral capsule by loading the tissue samples in tension and shear. An inverse finite element optimization routine was used to simulate the experiments and obtain material coefficients for each tissue sample. Cauchy stress–stretch curves were then generated to represent the mechanical response of each tissue sample to theoretical loading conditions. Based on several comparisons (average of the material coefficients, average stress–stretch curve for each region, and coefficients representing the average curves) between the normal and injured tissue samples, the mechanical properties of the injured tissue samples from multiple regions were found to be lower than those of the normal tissue in tension but not in shear. This finding indicates that anterior dislocation primarily affects the tensile behavior of the glenohumeral capsule rather than the shear behavior, and this phenomenon could be caused by plastic deformation of the matrix, permanent collagen fiber rotation, and/or collagen fiber failure. These results suggest that plication and suturing may not be sufficient to return stability to the shoulder after dislocation in all individuals. Thus, surgeons may need to perform a procedure that reinforces or stiffens the tissue itself, such as reconstruction or augmentation, to improve repair procedures.  相似文献   

11.
S. Shimoda 《Photosynthetica》2012,50(3):387-394
Photosynthetic parameters and leaf carbon isotope composition (??13C) in contrasting rice genotypes in relation to supplemental nitrogen (N) application and water management during the grain-filling period were compared. The changes in stomatal conductance (g s) and ratio of intercellular to ambient CO2 mole fraction (C i/C a) depended on the leaf nitrogen concentration (leaf N) in both ??Hinohikari?? (temperate japonica genotype) and ??IR36?? (indica genotype). In ??Hinohikari??, ??13C reflects photosynthetic gas exchange during the grain-filling period, which is indicated by the significant response of ??13C to leaf N. In contrast, in ??IR36?? ??13C did not depend on leaf N. This varietal difference in ??13C to leaf N can be attributed to a difference in the timing of leaf senescence. In ??IR36??, leaf N and photosynthetic parameters decreased more rapidly, indicating earlier senescence and a shorter grain-filling period in comparison with ??Hinohikari??. The significant increase in shoot dry mass in ??Hinohikari?? resulting from supplemental N application, compared with nonsignificant effect observed in ??IR36??, suggests that the timing of senescence in relation to the grainfilling period has a preponderant influence on productivity.  相似文献   

12.
Flours and isolated starches from three different cultivars (1544-8, 1658-11 and 1760-8) of pea grown under identical environmental conditions were evaluated for their physicochemical properties and in vitro digestibility. The protein content, total starch content and apparent amylose content of pea flour ranged from 24.4 to 26.3%, 48.8 to 50.2%, and 13.9 to 16.7%, respectively. In pea starches, the 1760-8 showed higher apparent amylose content and total starch content than the other cultivars. Pea starch granules were irregularly shaped, ranging from oval to round with a smooth surface. All pea starches showed C-type X-ray diffraction pattern with relative crystallinity ranging between 23.7 and 24.7%. Pea starch had only a single endothermic transition (12.1-14.2 J/g) in the DSC thermogram, whereas pea flour showed two separate endothermic transitions corresponding to starch gelatinization (4.54-4.71 J/g) and disruption of the amylose-lipid complex (0.36-0.78 J/g). In pea cultivars, the 1760-8 had significantly higher setback and final viscosity than the other cultivars in both pea flour (672 and 1170 cP, respectively) and isolated starch (2901 and 4811 cP). The average branch chain length of pea starches ranged from 20.1 to 20.3. The 1760-8 displayed a larger proportion of short branch chains, DP (degree of polymerization) 6-12 (21.1%), and a smaller proportion of long branch chains, DP ≥ 37 (8.4%). The RDS, SDS and RS contents of pea flour ranged from 23.7 to 24.1%, 11.3 to 12.8%, and 13.2 to 14.8%, respectively. In pea starches, the 1760-8 showed a lower RDS content but higher SDS and RS contents. The expected glycemic index (eGI), based on the hydrolysis index, ranged from 36.9 to 37.7 and 69.8 to 70.7 for pea flour and isolated pea starch, respectively.  相似文献   

13.
Information on the structure and character of immunoglobulin of fishes is essential in health management. A study was carried out to characterize the serum immunoglobulin (IgM) of the Indian major carp, rohu Labeo rohita (Ham.). Rohu (500g) were immunised with bovine serum albumin (BSA) and the anti-BSA antibody was purified employing BSA-CL agarose affinity column chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified Ig in a 3% gel under non-reduced conditions revealed a single protein having a molecular weight of 850kDa. Analysis of the purified serum in 10% SDS-PAGE under reduced conditions revealed that the immunoglobulin contained heavy and light chains with molecular weights of 85 and 23kDa, respectively. A polyclonal mouse anti-rohu IgM was prepared and used in an immunodot test which showed a specific reaction of the crude rohu anti-BSA antiserum and the purified anti-BSA IgM with BSA. Results indicate that the immunoglobulin of L. rohita is tetrameric IgM, similar to that of other fishes.  相似文献   

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A growth ring of an adult Norway spruce (Picea abies [L] Karst.) was analyzed to a high resolution at the single cell level with respect to structural and mechanical changes during the growth period. For this purpose structural characterization was performed by means of light microscopy, scanning electron microscopy and wide angle X-ray diffraction for investigating the geometry of cells, their cell wall fractions and cellulose microfibril angles (MFA). The mechanical properties were determined in microtensile tests on individual tracheids which had been taken from sequentially cut tangential slices. The results revealed pronounced differences in tensile stiffness between earlywood and latewood cells but only minor differences in tensile stiffness between the cell walls of both tissue types. These comparatively small changes in cell wall stiffness across the growth ring were caused by slight changes in MFA. The findings suggest that trees mainly vary cell size to optimize water transport and mechanical stability during the growth period and that modification of the cell wall organisation plays a minor role.  相似文献   

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The heterogeneous Indian tea germplasm includes ‘China’, ‘Assam’, ‘Cambod’, and their hybrids which were evaluated using biochemical markers viz., total catechin and their fractions, for varietal identification and characterization. Principal component analysis (PCA) of biochemical characters showed that the total catechin and trihydroxylated catechin has higher eigenvalues. The first two principal components (PCs) could differentiate more than 90% of the clones studied. This grouping based on first two principal component matrices differentiated ‘China’, and their hybrids with ‘Assam’ and ‘Cambod’ variety. Morphologically indistinct large‐leaved ‘Cambod’ variety and ‘Assam’ varieties could not be differentiated using biochemical markers, since both varietal types taxonomically belong to a single species. Clones of ‘China’ type showed low total catechin content and catechin ratio which are distinctly grouped. The ‘China–Assam’ and ‘China–Cambod’ hybrids formed intermediate groups between ‘China’ PC group and ‘Cambod’/‘Assam’ PC groups, providing evidence for genetic control of catechin ratio variation. Tea clones which are differentially positioned in the PC group could be explained based on the genetic contribution by other varietal type as parents. This biochemical characterization will be a useful tool in the development of quality‐tea clones with different proportion of total catechin and their fractions.  相似文献   

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 从金针菇Flammulina velutipes(Curt.ex Fr.)Sing.子实体中提取水溶性多糖,经乙醇分级,DEAE-Sephadex A-25纯化,得PA_5DE。以聚丙烯酰胺凝胶电泳和凝胶柱Sepharose 4B层析证明是化学均一性多糖,分子量是47.1万。用GLC、I.R、~13C-N.M.R.分析表明含有D-葡萄糖、D-甘露糖、D-岩藻糖。PA_5DE分子可能具有分支结构,含β-型糖苷键,存在β(1→3)和β(1→6)型糖苷键连接,并有抑制肿瘤S-180的活性。  相似文献   

18.
Catla catla, Labeo rohita, and Cirrhinus mrigala represent important alimentary fish in India. Their reproduction/breeding depends on seasons. Fish perceive external factors-stimuli and chemical signals through the olfactory system that plays the key role in central regulation of reproduction. However, no electron microscopy data are available on organization of olfactory components of these fish. We studied organization of the olfactory organ in male L. rohita using scanning (SEM) and transmission electron microscopy (TEM). This organ consists of olfactory epithelium, a short nerve, and olfactory bulb. The olfactory organ is ovoid in shape and consists of about 47–52 lamellae in adults and about 14–20 lamellae in fingerlings. These lamellae originate from the midline raphe. By SEM, microvillar sensory and ciliated non-sensory cells were observed in the lamellae. TEM revealed microvillar receptor cell with rough endoplasmic reticulum and Golgi apparatus towards apical end. Basal cells were present at the base of receptor cell, supporting cells were located adjacent to the olfactory receptor neurons, while epithelial cells—in the nonsensory part of olfactory epithelium. Mast, blastema, and macrophage cells were also found at the basement membrane. This work is the first publication on ultrastructural organization of the olfactory system of the Indian major carp, which provides information about morphological and ultrastructural organization of the olfactory system and opens new avenues for further investigation of chemical neuroanatomy, sensory signal processing, and neural regulation of reproduction in the Indian major carp.  相似文献   

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Flooding evoked a differential response in the activities of enzymes of fermentation pathway in leaves and roots of flood sensitive (S-308) and flood-tolerant (SSG-59-3) cultivars of sorghum. Activities of alcohol dehydrogenase (ADH), lactate dehydrogenase (LDH) and alanine aminotransferase (AlaAT) enhanced in roots of SSG-59-3 during 72 h of flooding. In contrast, a transient increase in the activities was discerned in roots of S-308 up to 24 h flooding followed by a decline in activities of these enzymes. In leaves of SSG-59-3, the activities of ADH and LDH increased to about three fold during flooding stress as compared to that in the non-flooded control plants. Though elevation in activities of these enzymes was observed in leaves of S-308 up to 48 h of flooding, the magnitude of enhancement was much lower than that in SSG-59-3. Alanine aminotranferase activity depressed in leaves of both the cultivars but the level of decline was more pronounced in sensitive cultivar S-308 as compare to tolerant SSG-59-3. The amount of alcohol, lactic acid and alanine were higher in both roots and leaves of SSG-59-3 than that in S-308 during flooding stress. It is thus apparent that roots and leaves of flood tolerant variety tends to attain greater capacity to perform reactions of various fermentation pathways to sustain production of ATP under flooded conditions.  相似文献   

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