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1.
米邦塔食用仙人掌是我国近几年引入的经济作物,根据食用仙人掌受冻的气候指标,在最低气温对比观测基础上,运用清流县1961—2002年最低气温资料,分析食用仙人掌大棚栽培安全越冬的气象条件,并讨论如何利用山地气候资源提高安全越冬机率,所得结果有益于当地趋利避害发展食用仙人掌。  相似文献   

2.
70年代以来,日本北海道某些地区的梨树新发生了一种病害。发病的梨树,行旬果梗、叶梗、变黑、萎蔫,然后是果穗、果枝变黑、萎蔫,最后导致整个结果母枝枯死。该病症状类似果树火疫病,病原是一种细菌,不侵染其他果树,只染梨树,故定命为“梨细菌性枝枯病”。  相似文献   

3.
草果是一种地域性非常明显的姜科、豆蔻属多年生茎丛生草本植物,属于重要的林下资源保护、开发性产品。近年来,草果种植的规模逐渐扩大,经济效益也不断提升,但草果种植面临萎蔫性死亡的威胁,必须采取相应的防治技术加以解决。基于此,介绍了草果萎蔫性病害发生的时间和症状,分析了草果萎蔫性死亡的病因,详细探讨了草果萎蔫性死亡的防治技术,从中对草果萎蔫性死亡的应对有了更深刻的了解。  相似文献   

4.
为实现植物水分状况的非接触式测量,最大程度减少测量对植物生长的影响,该文采用非接触式激光扫描测量方法获取植物叶片三维形态信息,通过测量植物叶片的体态萎蔫特征反映植物亏水胁迫状况。运用微分几何算法、二维傅里叶谱分析法、垂直投影叶面积法以及标准差法分别定义了4种植物萎蔫指数:基于微分几何算法的萎蔫体态指数、基于二维傅里叶谱分析的萎蔫指数、基于垂直投影叶面积的萎蔫指数和基于标准差方法的萎蔫指数,定量刻画植物萎蔫状态。试验分析了萎蔫指数的日变化过程,通过与植物茎秆直径的比较,得出定义的指数可以有效表征植物水分的结论。结合环境参数(太阳全辐射和环境温度)进行了相关分析,研究环境对植物水分的影响。最后比较了4种萎蔫指数刻画萎蔫状态的有效性。研究结果表明:萎蔫指数(以萎蔫体态指数为例)与太阳全辐射、环境温度和茎秆直径均线性相关,决定系数分别为0.736、0.785和0.845。4种指数比较中,萎蔫体态指数、基于二维傅里叶谱分析的萎蔫指数、基于垂直投影叶面积的萎蔫指数刻画叶片萎蔫效果相似,这3种指数与植物茎秆直径的线性相关系数分别为0.841、0.849、0.800。相比之下,基于标准差的萎蔫指数刻画萎蔫效果较差且与茎秆直径相关性也较低(R2=0.640)。该研究可为植物水分状况的非接触式测量提供一种有效的方法。  相似文献   

5.
基于叶片分形维数的植物亏水胁迫萎蔫体态测量方法   总被引:1,自引:1,他引:0  
该文借助基于激光斜射测距原理的3D扫描装置,快速获取西葫芦叶面形态的原始信息,在此基础上通过叶面形态的变化达到研究植株亏水胁迫的目的。定义了叶面分形维数作为刻画叶片萎蔫形态的量化指数——萎蔫指数。根据不同萎蔫程度(10个萎蔫水平)的叶片形态3D测量数据,对分形维数所定义的叶片萎蔫指数分别结合土壤温度与光照强度分析了统计相关性。试验结果表明:在保持田间持水量不变条件下,叶面分形维数满足萎蔫状态的单调变化趋势;激光扫描是获取叶面形态的有效方法;叶片的分形维数(萎蔫指数)与土壤温度、光照强度都成负相关性,并以分形维数为因变量,土壤温度和光照强度为自变量,得出了三者之间多元回归模型。由此可得:以分形维数定义的叶片萎蔫指数可以作为精准节水灌溉的一个控制指标,有效指导节水灌溉。  相似文献   

6.
萎蔫系数是确定土壤有效水范围、储量和对植物有效性的关键因子,但现有的基于植物形态变化测定的萎蔫系数存在生理意义不明确及难以在田间原位测定的缺陷。为此,本研究利用自然干旱下的盆栽试验,测定了2种土壤质地(黄土高原区黄绵土和南方丘陵区红壤)下4种植物(大豆Glycine max L.、向日葵Helianthus annuus L.、苜蓿Medicago sativa L.、羊草Leymus chinensis (Trin.) Tzvel)幼苗的萎蔫系数及叶片气体交换参数对土壤水分含量变化的动态响应过程,探讨了基于植物气体交换参数确定的土壤水分下限阈值与萎蔫系数的关系。结果表明:(1)土壤质地和植物抗旱性显著影响萎蔫系数,且影响在永久萎蔫时对应的土壤水势。4种植物在黄绵土下的萎蔫系数分别为0.083 cm3?cm-3(向日葵)>0.081 cm3?cm-3(大豆)>0.072 cm3?cm-3(羊草)>0.060 cm3?cm-3(苜蓿),在红壤下的萎蔫系数表现为0.188 cm3?cm-3(向日葵)>0.180 cm3?cm-3(大豆)>0.174 cm3?cm-3(羊草)>0.172 cm3?cm-3(苜蓿)。4种植物在红壤上的萎蔫系数均大于黄绵土,且植物抗旱性越强,其萎蔫系数越低。(2)利用三次函数模拟气孔导度变化确定的土壤水分下限阈值与萎蔫系数存在高度一致性。因此,萎蔫系数可基于植物气体交换参数进行间接估算。  相似文献   

7.
广西南宁市人民公园是广西较早进行仙人掌科星球属植物引种栽培的单位,经过多年实践,掌握了仙人掌科星球属的栽培繁殖技术。基于此,分析了仙人掌科星球属植物在南宁市的栽培繁殖技术。  相似文献   

8.
通过对南京市不同土地利用下的土壤容重、孔隙度和土壤水分特征曲线的测定,研究了压实对土壤水分特征参数的影响。结果表明城市土壤存在严重的压实退化现象,土壤容重和孔隙度能够很好地反映土壤的压实程度。随着压实程度的增加,土壤的田间持水量增加,萎蔫点含水量增加,而土壤的最大有效水含量却明显减少。所以,压实土壤对水分的调节能力下降,使其上生长的植物更不容易获得水分供应。  相似文献   

9.
针对干旱半干旱地区广泛存在的土壤干化问题,在深入分析植物萎蔫过程及其与土壤干化之间关系的基础上,提出了初始萎蔫湿度(IWP)的概念,作为界定土壤干化层的定量判定指标。以该指标为基础,提出了土壤干化层发生与否及其发生类型的判定方法,并就指标的实验测定等问题进行了探讨。最后以黄土高原为例,应用该判定系统对黄土高原典型地区的土壤干化层分布情况进行了研究。研究成果对干旱半干旱地区土壤干化层的识别、类型判定、评价及其数量描述以及植被建设具有重要的指导意义。  相似文献   

10.
微波辅助提取仙人掌多糖的工艺研究   总被引:17,自引:4,他引:17  
该文采用微波辅助法提取米邦塔仙人掌多糖,并与热回流提取方法进行比较。通过设计正交试验,得出优化的工艺条件:以水为提取剂,料液比1∶10(w/v),提取2次,每次提取3 min,微波炉功率700 W,选用70%乙醇沉淀。微波提取粗多糖的得率和含量分别为6.8%和8.5%,高于热回流提取粗多糖的得率4.7%和含量8.3%。微波提取不仅缩短了提取时间,降低提取剂用量,而且提高了仙人掌多糖得率。  相似文献   

11.
Biothiols, taurine, and flavonols, as well as tocopherols and carotenoids have been assessed in the edible pulp of Sicilian red (Sanguigna), yellow (Surfarina), and white (Muscaredda) cultivars of cactus pear. The yellow cultivar has the highest level of reduced glutathione (GSH, 8.1 +/- 0.78 mg/100 g pulp), whereas the white cultivar showed the highest amount of cysteine (1.21 +/- 0.12 mg/100 g pulp). Taurine accounted for 11.7 +/- 1.0 mg/100 g in the yellow pulp, while lower levels were measured in the others. With the exception of kaempferol in the yellow cultivar (2.7 +/- 0.2 microg/100 g pulp), the edible pulp of cactus pear was not a source of flavonols. Very low amounts of lipid-soluble antioxidant vitamins such as vitamin E and carotenoids were measured in all cultivars. As a consequence of industrial processing, a total loss of GSH and beta-carotene and a net decrease of vitamin C and cysteine were revealed in the fruit juice, whereas betalains, taurine, and vitamin E appeared to be less susceptible to degradation.  相似文献   

12.
Reproductive biology of the columnar cactus Escontria chiotilla was analysed in wild and silvicultural managed populations in the Tehuacán Valley, Central Mexico, where this cactus is under domestication because of its edible fruits. Anthesis is diurnal, flowers opening between 8:00 and 17:00 h, the period between 12:00 and 13:00 appearing to be crucial in pollination success since at this time the maximum opening of flowers, turgidity of stigma, and activity of flower visitors, as well as the highest nectar production and pollen release occur. The bees Apis mellifera, Bombus pensylvanicus and Xylocopa mexicanorum, and the hummingbirds Amazilia violiceps, Cynanthus sordidus and Cynanthus latirostris were the most frequent flower visitors during the crucial period, and were observed contacting both stamens and stigma of E. chiotilla. No differences were found in anthesis nor in flower visitors among both population types. Distances separating the populations studied and bridges of individuals of E. chiotilla between them are within the radius that bees and hummingbirds may travel, indicating that spatial barrier to pollen flow are unlikely. Breeding system is self-incompatible. Production of flowers occurs during the whole year in both population types, allowing continual pollen flow among them. This observation confirms reports of high gene flow among the populations studied in previous population genetics studies. The high pollen flow among wild and managed population explains that however the occurrence of artificial selection, the process of domestication is in incipient stages presumably because gene flow counteracts effects of artificial selection.  相似文献   

13.
Abstract

Polyacrylamides (PAM) and polysaccharides can be used as soil amendments to improve soil physical properties, including infiltration of water into soil. Mucilage from prickly pear cactus contains large polysaccharides. Two experiments were done to test the hypothesis that pretreating columns of soil with cactus extract would improve subsequent falling‐head ponded infiltration of water. One experiment tested samples from a loamy Alfisol, the other from a Vertisol. In both experiments we compared effects on infiltration between pretreatments of cactus extract, PAM used as a reference, and water as a control. In both experiments treatment effects were significant (P<0.05). Both cactus extract and PAM improved infiltration compared to the control. This is the first known report that cactus extract can be used to improve infiltration. Many questions remain regarding the mechanisms involved and the potential for practical use of cactus extract as a soil conditioner.  相似文献   

14.
There are scarce and conflicting reports on fruit yield (FY) and cladode nutrient concentrations for cactus pears (Opuntia spp.). The objective of this study was to examine the macro- and micronutrient cladode concentrations, the association between FY nutrient concentrations, and seasonal changes in macro- and micronutrients in fruiting cladodes of “Cristalina” cactus pear plants exposed to a nitrogen (N), phosphorus (P), and potassium (K) fertilization matrix over three growing seasons. The experiment was conducted in a randomized complete block design under field conditions. Seven samples of cladode were collected at different phenological stages for the measurement of N, P, K, calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and boron (B). The analysis suggested that the most important nutrients for FY (20.5 t ha?1) were N and P at 90 and 30 kg ha?1, respectively. The seasonal pattern for macro- and micronutrients is shown and discussed. The latest topic deserves further research for understanding the cactus pear ionome and suggesting mineral fertilization programs to the cactus pear growers.  相似文献   

15.
People of the Tehuacán Valley, Central Mexico utilise the columnar cactus Escontria chiotilla for their edible fruits, gathering them in the wild and in silviculturally managed populations. Silvicultural management consists in sparing and enhancing selectively, in disturbed areas, individual trees producing fruits of the better quality for consumption and commercialisation. Fruits of trees in silviculturally managed populations are generally larger (27.23 ± 0.39 cm) and heavier (11.10 ± 0.44 g), with a higher amount of pulp (4.84 ± 0.27 g), and more (532.72 ± 15.60) and heavier (0.78 ± 0.013 mg) seeds than in wild non-manipulated populations (22.62 ± 0.31 cm, 6.44 ± 0.22 g, 2.33 ± 0.11 g, 407.63 ± 20.67, and 0.62 ± 0.015 mg, respectively). Phenotypes of trees producing better fruits were significantly more abundant in manipulated populations than in the non-manipulated ones. Artificial selection appears to be the cause of such differences among populations and, therefore, domestication process of this plant species is seemingly occurring under silvicultural management.  相似文献   

16.
Total phenolics, ascorbic acid, and betalain contents of differently colored cactus pear clones (nine Opuntia ficus-indica [L.] Mill. clones and one O. robusta Wendl. clone) were investigated and related to their respective antioxidant potential assessed by Trolox-equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays. TEAC and ORAC values were very highly correlated with each other and also with values for total phenolics, betalain contents, and ascorbic acid concentrations. Total phenolics had the greatest contribution to ORAC and TEAC values. High-performance liquid chromatography (HPLC)-diode array detector (DAD)-tandem mass spectrometry (MS/MS) measurements of cactus pear juices permitted the differentiation of the clones based on variations in pigment patterns and betalain concentrations. The red and yellow betalains were absent in lime green colored cactus fruits. The ratio and concentration of these pigments were responsible for the yellow, orange, red, and purple colors in the other clones. Progeny of purple and lime green colored parents were characterized by 12% and 88% of plants bearing lime green and purple fruit, respectively. This implies that the genes for betalain production were lacking in the lime green fruits but could be provided by a parent with a complete set of genes, that is, purple fruits. Besides known pigments typical of Cactaceae, two unexpected betalains were identified. Whereas gomphrenin I was found for the first time in tissues of cactus plants, methionine-betaxanthin has never been described before as a genuine betalain. In addition to their alleged health-promoting properties, various combinations of yellow betaxanthins and red-purple betacyanins may allow the development of new food products without using artificial colorants.  相似文献   

17.
Betaxanthins, the yellow-orange water-soluble pigments from yellow beet (Beta vulgaris ssp. vulgaris cv. Bejo Zaden) and cactus pear (Opuntia ficus-indica cv. Gialla) have been investigated using an HPLC system compatible with mass spectrometry. Five novel betaxanthins were found and characterized as the immonium adducts of betalamic acid with serine, gamma-aminobutyric acid, valine, isoleucine, and phenylalanine. To enable concentration of betalain samples, desalting was performed by solid-phase extraction. With this technique, betacyanins could be separated from the betaxanthins using the pH-dependent retention characteristics of red and yellow betalains. The betaxanthin fraction was taken for the preparation of betalamic acid as a precursor for semisynthetic standards. The HPLC method was applied to yellow beet and cactus pear, revealing a more complex betalain profile than described earlier, thus proving its suitability for screening of betaxanthin-containing plants as potential sources for natural food colors.  相似文献   

18.
针对食用菌行业信息化的需要,运用计算机和网络技术构建食用菌产业信息化服务体系,同时建立了高效的应用示范。开展了食用菌技术集成和专家知识库建设、食用菌技术研发合作交流、技术与产品交易服务、科技远程培训系统建设,以及在食用菌行业的应用示范研究。体系信息量大、知识全面、图文声型并茂,能多角度、全方位地满足食用菌行业科技信息服务的需求。  相似文献   

19.
食用向日葵仿人工取盘采收台的设计   总被引:1,自引:1,他引:0  
针对现阶段人工取盘效率低、取盘成本高、籽粒易损失等问题,结合新疆食葵的种植模式和田间采收作业要求,设计了一种模仿人工取盘方式的食葵采收台,主要结构包括捡拾装置、输送装置、行走装置、集盘箱、动力传动系统。通过对食葵采收作业过程进行理论分析,确定了捡拾装置、输送装置等关键部件的结构参数和运动参数,建立三维实体模型并针对捡拾装置进行运动学分析,得出捡拾装置取盘杆的位移、速度、加速度变化规律;分析动力传动系统,确定各级链传动的传动比。试制出食葵采收台并以收获总损失率为试验目标,以插盘高度、取盘杆的转速、机组的前进速度为试验因素,进行田间采收试验。试验结果表明,食葵采收台可以完成葵盘采收、输送、收集等功能;食葵采收台工作时的较优组合为插盘高度为650 mm、机组的前进速度为0.88 m/s、取盘杆的转速为23 r/min,收获总损失率小于5%,能够满足新疆食葵收获的作业要求。  相似文献   

20.
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.  相似文献   

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