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1.
苹果试管苗不定根起源及其发育状况的研究 总被引:4,自引:0,他引:4
利用光学和扫描电子显微镜观察结果表明,经琼脂生根培养基诱导产生的长富—2苹果 (Malus pumila Mill.) 试管苗的不定根起源于维管形成层。这种不定根发育不良,根表面缺乏根毛,内部解剖构造为典型的初生结构。为避免因不定根吸收、运输能力差而影响试管苗移栽成活,宜采用通透性良好的基质进行瓶内或瓶外生根,可诱导出优质不定根。 相似文献
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番茄不同部位中糖含量和相关酶活性的研究 总被引:25,自引:2,他引:25
试验将番茄光合产物运转途径上叶片(源) 、运输系统以及果实(库) 区分开, 分别测定其糖的组成和含量以及糖代谢相关酶的活性。结果表明: 番茄光合产物运转途径上从“源”到“库”各部位糖的组成和含量不同。叶肉中果糖的含量最高, 蔗糖的含量最低; 中筋中以果糖和葡萄糖为主; 叶柄维管束中葡萄糖含量最高, 蔗糖含量次之, 果糖含量最低。节间和果柄维管束中主要含有蔗糖。果实维管束以及果实内各部位中则主要含有葡萄糖和果糖, 且两者含量无显著差异, 蔗糖含量很低。萼片中葡萄糖含量最高, 蔗糖含量最低; 果蒂中3种糖含量均较高且无显著差异。番茄叶肉及光合产物运转组织中转化酶活性很低, 而在库器官的非维管组织中转化酶活性较高。果蒂中的蔗糖合成酶( SS) 活性最高, 其次是叶肉和运转组织, 果实内各部位中SS活性较低。在合成蔗糖的器官—叶肉中, 有较高的蔗糖磷酸合成酶( SPS) 活性, 运转组织中的SPS活性较叶肉中降低, 但果柄维管束和果实维管束中则表现出较高SPS活性, 果肉、果胶质胎座及心室隔壁中的SPS活性最低。 相似文献
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呼伦贝尔草原区是我国北方重要的生态屏障,近年来不合理的利用方式导致该地区退化草地面积不断扩大,为了探究牧草补播时间及补播比例对呼伦贝尔退化草甸草原植物群落特征的影响,为该地区退化草地修复提供依据。本研究以羊草(Leymus chinensis(Trin.) Tzvel.)和黄花苜蓿(Medicago falcata L.)为试验材料,采用双因素随机区组试验设计,通过测定幼苗数、高度、生物量等群落指标,并综合评价补播效果,结果表明:夏播羊草和黄花苜蓿幼苗数量显著高于春播和秋播(P<0.05),夏播和秋播植物群落总生物量呈增加趋势,春播则呈减少趋势;补播措施提高了退化草地植物群落Shannon-Weiner指数、Simpson指数和Pielou指数,豆科和禾本科植物重要值呈增加趋势,其他科植物呈下降趋势。呼伦贝尔地区夏季补播羊草和黄花苜蓿以1∶3补播效果较好,而春播由于恢复时间短,需进一步观察。 相似文献
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以胶东半岛老的果园中土壤为试材,采用逐步稀释法,涂平板于孟加拉红培养基中,根据形态和分子方法鉴定分离木霉菌。分离出的木霉菌与苹果主要病害对峙培养在不同pH的培养基上,观察不同pH条件下,对真菌病害的抑制效果。土壤有机质和pH是目前胶东果园的主要问题,采用正交法设计,研究了不同的土壤条件对木霉菌生长的影响。结果表明:在不同pH条件下,木霉菌抑制苹果病原真菌的效果不同,木霉菌在不同的pH条件下对腐烂病(Valsa mali)和炭疽病(Colletotrichum gloeosporioides)均可以抑制,但对轮纹病(Physalospora piricola Nose)只有在pH 6.0时没有效果外,其它pH时都对轮纹病有抑制作用。在土壤pH 6.5和土壤有机质含量为75 g·kg-1时,最有利于木霉菌定殖。同时还发现木霉菌对土壤的pH具有调节作用,无论在碱性条件下,还是酸性条件下,均可以使土壤pH趋于中性,另外木霉菌可以增加土壤有机质含量,特别是在高土壤有机质含量的情况下,增加更加显著。总之,分离出的木霉菌对苹果腐烂病、炭疽病和轮纹病抑制效果好。土壤pH和有机质含量对木霉菌的生长有影响,高土壤有机质含量和中性土壤有利于木霉菌定殖。另外,木霉菌能有效地改良土壤有机质含量和土壤pH。 相似文献
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Processing tomato quality as affected by irrigation scheduling 总被引:5,自引:0,他引:5
Fabio Favati Stella Lovelli Fernanda Galgano Vito Miccolis Teodoro Di Tommaso Vincenzo Candido 《Scientia Horticulturae》2009,122(4):562-571
In Southern Italy the paucity of water is a very important problem and due to the fundamental importance of the water for the processing tomato, in this study the influence of irrigation on processing tomato quality was investigated in the years 2002 and 2003. A hybrid processing tomato (Lycopersicon esculentum L. Mill cv. Ability) was treated with different water regimes obtained combining amount of water and irrigation interval. The effects of the trials were evaluated taking into account the physical and chemical characteristics of the fruits, as well as the content in antioxidants moieties. Furthermore, the relationship among all the quality parameters and the seasonal amount of irrigation water was evaluated.The results, comparing different water regimes obtained combining amount of water and irrigation interval, gave useful indications on the possibility to improve nutritional tomato quality by reducing irrigation water during tomato cropping. In particular, relatively to the Mediterranean areas of tomato cultivation and to the texture of the soil considered in this study, the best compromise between quality and quantity of the processing tomato fruit was achieved both with the extension of the irrigation interval (L40 or L60) and with the limitation of irrigation volume for the second part of the tomato crop cycle (thesis 100-50). Extending the irrigation interval and limiting irrigation volume for the second part of the tomato crop cycle, appeared to be the best management strategy to optimize the yield and nutritional quality of processing tomato. 相似文献
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Bayzid Yousefi Seyed Reza Tabaei-Aghdaei Farrokh Darvish Mohammad Hassan Assareh 《Scientia Horticulturae》2009
The flower yield stability of Damask rose as an important medicinal and aromatic plant at different environments has not been well documented. In order to evaluate flower yield and stability, 35 landraces of Damask rose were studied at 8 locations in Iran during 2007–2008. Analysis of variance revealed significant differences (p ≤ 0.01) among landraces (G), environments (E), locations (L) and for landrace × environment (GE) and landrace × location (GL) interactions. Both GE and GL interactions were mainly crossover, a large portion of which was accounted for by non-linear (unpredictable) component. The landraces of IS9, YZ2, WA1, IS7 and IS1 with 3120.63, 2941.63, 2894.62, 2769.15 and 2716.92 kg/ha respectively produced the highest flower yield among studied landraces. Kerman with average flower yield of 3635.46 kg/ha produced the highest yield among studied locations. According to the results, most of landraces that originated from temperate, warm temperate and arid regions produced higher flower yield than those from cool, cool temperate, semi-arid and humid regions. The landraces of YZ2, IS5, IS8, IS4, KZ1, AR1, IS3 and BA1 were stable and YZ2, IS5, IS8, IS4, KZ1, AR1 IS6, IS3, BA1, IS10 and YZ1 were adaptable landraces for flower yield according to Eberhart and Russell (1966) model. The presence of some high flower yield and stable landraces such as YZ2 and IS5 suggests that a genotype can demonstrate high flower yield and stability for yield simultaneously. Thus, simultaneous selection for flower yield and stability using nonparametric methods could be possible. In addition, taking into consideration flower yield and stability potential, the landraces of YZ2, IS5, IS8, IS4 and KZ1 as general stable, adaptable, and high flower yield are recommended. Furthermore, the landraces of IS9 and WA1 as high flower yield and specific adaptable landraces can be recommended for temperate and arid areas and the landraces of IS7 and IS1 for semitemperate and cool areas. 相似文献
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