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1.
J. G. Wu    Z. Li    Y. Liu    H. L. Liu  T. D. Fu 《Plant Breeding》1997,116(3):251-257
A pentaploid hybrid plant (2n= 50, AACCO) between Brassica napus (AACC) and Orychophragmus violaceus (OO) showed matroclinous morphology and some patroclinous characters. Cloned progenies were mixoploid, consisting of various cells with 38–53 chromosomes, half of the cells with 50 chromosomes. The 50 chromosomes were mainly paired as 25 bivalents and segregated as 25:25 or 22:28; many other segregations were observed in some cells. Progenies produced by selfing had 38–47 chromosomes. Plants with 38 chromosomes were cytologically stable; in all other plants the chromosome number of individual cells varied between the genotype-specific maximum number and 38, indicating loss of chromosomes during mitosis. The mixoploid plants with 44 chromosomes mainly produced two kinds of mixoploid progenies with 44 and 41 chromosomes, respectively. All plants with 2n= 38 had the same morphology as the parental B. napus and were normal in fertility. These chromosome pairings and segregations in the pentaploid and its progeny support the hypothesis that O. violaceus is a natural polyploid species with a basic chromosome number of 3.  相似文献   
2.
对甘蓝型油菜与诸葛菜的杂种的花粉母细胞的减数分裂的观察表明,染色体组分割现象在该杂种中广泛存在。对染色体组分割现象的分析表明,核质杂种的形成机制在于“染色体组分割现象”。同时还分析了“诸葛菜”核在不同质情况下的行为。  相似文献   
3.
摘 要:田间试验条件下,研究不同水肥处理对二月兰生长,及其翻压后后茬花生产量和养分累积的变化。结果表明,灌溉和施肥可显著促进二月兰生长。在绿肥季,不论施肥与否,灌溉处理均可显著提高二月兰的生物量和N、P、K养分含量, NPW(绿肥季施氮磷肥和灌溉)和CKW处理(绿肥季不施肥,只进行灌溉处理)的二月兰生物量和N、P、K养分含量分别比相应的未灌溉处理提高了66.47%和63.97%、76.95%和32.36%、88.31%和9.80%、21.71%和15.56%。二月兰翻压的养分还田量为91.04~260.23 kg/hm2,约占花生季化肥总养分的27.59%~78.86%。与冬闲处理(CF)相比,不同施肥和灌溉处理的绿肥翻压均促进了花生产量和养分累积,及土壤养分含量的提高,其中以EN处理的提升效果最明显。周年等养分条件下,花生季35.00%氮和/或42.86%磷肥料前移至绿肥季,可明显促进绿肥养分还田量的增加,后茬花生产量不同程度增加(增幅22.82%~41.18%)。综上,在适量灌溉和施肥条件下,二月兰生物量明显增加,进而促进后茬花生产量增加及养分累积。研究结果可为我国绿肥农田应用及化肥减施提供数据支撑和实践依据。  相似文献   
4.
The amount of organic acids in root exudates rapidly increases under phosphorus (P) deficiency. Loss of carbon from root-exuded organic acids, which are derived from plant net photosynthetic products, is generally considered negligible. The present study aimed to study the characteristics of root-exuded organic acids, extraction of phosphorus (P extraction) in calcareous soil and the expression of organic carbon from root-exuded organic acids in two woody Moraceae plants (Broussonetia papyrifera L. Vent and Morus alba L.) and two herbaceous cruciferous plants (Orychophragmus violaceus L. Schulz and Brassica napus L.) under two P levels (P-normal and P-deficient). P extraction and the amount of root-exuded organic acids simultaneously and disproportionately increased in the four plant species tested under P deficiency. The maximum P-extracting capability of the four plant species was observed after 40 days of treatment. Additionally, the response of root-exuded organic acids induced by P deficiency was species-specific. B. papyrifera extracted more P in calcareous soil, and expended less organic acid for the same P-extraction than M. alba. Similarly, O. violaceus extracted more P in calcareous soil, and consumed less organic acid for the same level of P-extraction than B. napus. Root-exuded oxalic and malic acids accounted for most of the increment of P extraction in woody Moraceae plants, while root-exuded citric acid accounted for most of the increment in P extraction in herbaceous cruciferous plants. B. papyrifera and O. violaceus exhibited the strongest P-extracting capability at lower expense of organic carbon over the treatment duration in the four plant species. O. violaceus had the most rapid response of root-exuded organic acids to P deficiency, while B. napus had the slowest response. Thus, rapid response with low organic carbon cost and high efficiency of extraction on P in calcareous soil may underlie the strong adaptability of B. papyrifera and O. violaceus to a Karst environment.  相似文献   
5.
6.
In the cross between B. napus with OguCMS x Orychophragmus violaceus, pre-fertilizationcompatibility was observed. An intergeneric hybrid was successfully obtained by usingovary culture. The hybrid status was confirmed by cytology, morphology, fertility,isozyme and miosis analysis. The seed setting rate was 0.0072%. An amphidiploid of thehybrid was also produced by the use of chromosome-doubling method with 0.1% colchicinestreatment. Obtaining this hybrid and its amphidiploid has important theoretical andutilization value.  相似文献   
7.
王欣  夏新奎  徐固华 《安徽农业科学》2007,35(22):6705-6706
采用微波辅助萃取乙醇浸提法从诸葛菜中提取黄酮类物质,对所提取的黄酮类物质进行验证,并用紫外分光光度法测定其含量。结果表明,诸葛菜中总黄酮含量为0.380 7 mg/ml,回收率为97.79%,其纯度和产率均较高。该方法采用全物理过程,无任何污染,是提取诸葛菜中黄酮类物质的有效途径。  相似文献   
8.
诸葛菜试管苗的光合特性及其对CO2浓度升高的响应   总被引:2,自引:0,他引:2  
用Li-840 CO2/H2O气体分析仪对诸葛菜试管苗的光合特性及其对CO2升高的响应进行研究。结果表明:诸葛菜试管苗的光合速率日变化不大,午间没有明显的“午休”现象。在不同光源下实际光合速率的比较,在相同的光强下LED-红光下的试管苗的光合速率最高,LED-蓝光次之。正常大气条件下,LED-蓝光在70μmol/(m2.s)光强下的诸葛菜试管苗的CO2饱和点为5 058μmol/mol,CO2补偿点为266μmol/mol。  相似文献   
9.
抗除草剂转基因油菜向杂草诸葛菜的潜在基因漂移   总被引:9,自引:0,他引:9  
以抗除草剂草甘膦和草丁膦转基因油菜为父本 ,诸葛菜为母本 ,在人工授粉条件下研究抗性基因向诸葛菜的潜在基因漂移。采用荧光显微镜观察转基因油菜花粉在诸葛菜柱头上的萌发生长情况 ,并与诸葛菜自花授粉的情况进行比较。结果显示 2种转基因油菜花粉在诸葛菜柱头上的萌发生长情况类似。花粉粘合的数量比自交时显著减少 ,出现粘合延迟现象 ;花粉在柱头上不能正常萌发生长 ,有的呈现明显的畸形 ,花粉管不能穿过乳突细胞 ,更不能进入花柱和胚囊发生受精 ,这些结果表明两者的亲和性较差。授转基因油菜的花粉后诸葛菜不能结实也进一步证明了两者的亲和性较差。上述结果表明抗除草剂转基因油菜的抗性基因向诸葛菜漂移的可能性较小。  相似文献   
10.
为了解南京地区早春植物二月兰( Orychophragmus violaceus)的访花昆虫种类及其行为特点,采用捕捉、鉴定、视频、图像采集等方法,对二月兰访花昆虫的种类、访花行为进行了调查研究。结果表明:二月兰的访花昆虫有23种,分别隶属5目、13科,其中东方蜜蜂( Apis cerana)、黄胸木蜂( Xly ocopa appendiculata)、长木蜂( Biluna tranquabarorum)、赤足木蜂(Xylocopa rufipes)、黑颚条蜂(Anthophora mle anognatha)、黑带食蚜蝇(Episyrphus baltea-tus)及暗脉菜粉蝶( Piersi naip )为主要访花昆虫;它们的日活动规律分为单峰型和双峰型2种;黑颚条蜂弹花频率最高,东方蜜蜂的弹花频率最低;黄胸木蜂、长木蜂以及赤足木蜂在开花盛期的弹花频率高于开花末期,东方蜜蜂和黑颚条蜂在开花末期的弹花频率高于开花盛期;黑颚条蜂的每花停留时间最短,东方蜜蜂的停留时间最长。  相似文献   
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