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81.
对菠萝品种选育与栽培技术研究进展进行概括,包括菠萝种质资源收集评价、杂交育种、诱变选种、基因工程育种研究,以及菠萝种苗繁育、生产种植、催花、防寒防晒等栽培技术研究的新进展。此外,对未来菠萝育种研究与栽培技术研究主要方向进行展望。在菠萝种质资源精准评价的基础上,建立以常规杂交育种、诱变育种为主体,基因工程育种为辅助的育种体系是菠萝育种研究的主要方向。开展菠萝“黑心病”和“水菠萝”发生的机理研究,从生产源头降低“黑心病”和“水菠萝”发生的栽培技术措施研究,以及无损检测技术与智能化、省力化种植技术研究等是国内菠萝高效栽培技术研究的主要内容之一。  相似文献   
82.
Four, male, growing Thai swamp buffaloes (197 ± 5.3 kg and all 1 year old) were used to evaluate the effects of concentrate added to pineapple waste silage in differing ratios, to form a complete diet, studying in vivo digestion, the rate of passage, microbial protein synthesis and blood metabolites. Animals were fed ad libitum with 4 diets, using four combinations of pineapple waste silage (P) and concentrate (C), in the proportions (on a dry matter basis) of 0.8:0.2 (P80:C20), 0.6:0.4 (P60:C40), 0.4:0.6 (P40:C60) and 0.2:0.8 (P20:C80). The results showed that the intakes of dry matter (DM), organic matter (OM), nitrogen (N), the N-balance, urinary purine derivatives (PD) excretion, the ratios of allantoin to creatinine (CR), PD to CR, the plasma urea-N (PUN) and insulin increased in the animals, but the intake of neutral detergent fiber (NDF), the coefficient of whole tract, apparent digestibility of NDF, the transit time (TT) and the mean retention time (TMRT) decreased, when the proportion of concentrate in the diet increased. This study indicated that the proportion of P40:C60 in the diet produced the best efficiency of urinary PD excretion (mmol) per digestible OM intake (kg DOMI).  相似文献   
83.
采用高效液相色谱法测定56份菠萝种质成熟果实中的有机酸组分及含量.结果表明,菠萝果实中有机酸主要由柠檬酸、苹果酸和奎宁酸组成,其中柠檬酸含量最高,变化范围在1.80~8.09 mg/g FW,平均值4.82 mg/g FW,占有机酸的64.73%,奎宁酸次之,苹果酸第三.奎宁酸在各种质间的变异相对稳定;柠檬酸和苹果酸变异较大,分别为33.86%和37.92%.根据柠檬酸所占的比例,可将菠萝种质划分为柠檬酸优势型.  相似文献   
84.
为了利用色素比较评价不同菠萝品种的农艺性状,选取定植在江门地区的4个菠萝品种叶片为试验材料。结果表明,‘金菠萝’的SPAD值和类胡萝卜素最高,显著高于其他3个品种。‘巴厘’的花青苷含量显著高于其他3个品种,‘卡因’的花青苷含量显著高于‘黄金菠萝’。对于绿色叶片而言,高叶绿素含量品种的叶色深绿,低含量的叶色黄绿;对于彩色叶片植株而言,花青苷含量起主导作用。4个品种在色素含量方面有较大差异,色素可以作为进行菠萝品种评价和鉴别的重要指标。  相似文献   
85.
菠萝叶基愈伤组织诱导体细胞胚   总被引:6,自引:1,他引:6  
以菠萝[Ananascomosus(L.)Merr.]吸芽上的叶基部组织为材料,研究了2,4-D、NAA、BA、TDZ在菠萝愈伤组织诱导体细胞胚过程中的影响。结果表明,2,4-D在体细胞胚诱导过程中起着极为重要的作用,其适宜浓度为5mg/L,适当浓度(1mg/L)的BA在降低畸形胚比例和增加体细胞胚发生率方面有重要作用,但BA也会促进愈伤组织分化不定芽;低浓度的TDZ与BA效果相似,在不同生长调节物质处理组合中,MS+0.01mg/LTDZ+5mg/L2,4-D培养基的体细胞胚发生率最高(97%)。低浓度NAA(2 ̄5mg/L)利于非胚性愈伤组织的增殖,而高浓度的NAA虽能促进体细胞胚发生,但这种体细胞胚很难继续增殖,在萌发时只生根不发芽。成熟体细胞胚在MS+0.2%活性炭上30d时的转株率为22.7%。  相似文献   
86.
The use of CPPU for efficient propagation of pineapple   总被引:4,自引:0,他引:4  
The use of forchlorfenuron (N-(2-chloro-4-pyridyl)-N′-phenylurea) (CPPU) for efficient propagation of pineapples was investigated. About 85% of axillary buds can be forced to sprout by soaking defoliated stem pieces (12 cm in length) in a 2.5 or 5.0 mg l−1 CPPU solution for more than 3 h. The use of old stems taken from the third or fourth ratoon plants had the advantage of less liability to fungal decay, as compared to young stems from the first crop plants. The CPPU treatment combined with the removal of shoots from stems at monthly intervals significantly increased the number of shoots per stem piece (about 15 shoots per piece at 5.0 mg l−1 CPPU), and resulted in a more uniform shoot size (the percentage of shoots within a range of 5–15 cm in length was about 90% at 5.0 mg l−1 CPPU). The rooting of shoots was easily promoted within 1 month by treating the basal portion of shoots with 20 mg l−1 indole-3-butyric acid (IBA) for 15 min. The CPPU method required about 5 months for plantlet propagation. From these results, we found that pineapple plantlets could be efficiently propagated by the following method: (1) soaking defoliated stems in a 2.5–5.0 mg l−1 CPPU solution for more than 3 h; (2) harvest of developed shoots from the stems at regular intervals; and (3) promotion of rooting on the shoots at 20 mg l−1 IBA for 15 min.  相似文献   
87.
为了解水心病菠萝果实生理指标和内源激素含量的变化特征,本研究以菠萝主栽品种‘巴厘’为材料,采用液质联用(LC-MS)、高效液相色谱(HPLC)等方法测定了不同发病程度的水心病菠萝果实中主要内源激素、单糖、可溶性固形物、可滴定酸和维生素C(Vc)、丙二醛(MDA)含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性,并分析了水心病发病程度、内源激素和抗氧化酶活性间的相关性。结果表明,不同发病程度水心病菠萝可溶性固形物、Vc和糖含量、SOD和POD酶活性以及内源激素玉米素(ZT)、茉莉酸(JA)和脱落酸(ABA)含量均比对照显著下降,且随着发病程度的加深下降幅度增加;不同发病程度水心病菠萝CAT酶活性、MDA含量和SA含量较对照显著提高;可滴定酸含量、果糖和葡萄糖含量在轻度发病果中含量较对照明显增加,在中度发病果中含量显著降低,而1-氨基环丙烷羧酸(ACC)含量变化趋势与其刚好相反。相关分析表明,菠萝水心病病害级别与内源激素ZT、JA和ABA含量呈显著负相关,相关系数分别为-0.98、-0.98和-0.94;与SA含量呈显著正相关,相关系数为0.93。一方面水心病降低了菠萝果实糖酸比和Vc含量,导致果实品质下降;另一方面菠萝通过调节内源激素ZT、JA、ABA和SA含量,进而调控SOD、POD和CAT活性,增强对水心病的防御反应。  相似文献   
88.
菠萝果肉颜色的形成与类胡萝卜素组分变化的关系   总被引:4,自引:0,他引:4  
为了分析不同类型菠萝果实成熟过程中果肉类胡萝卜素成分的变化特点及其外观颜色差异形成的因素,以深黄色果肉的巴厘种和浅黄色果肉的卡因种菠萝为材料,应用高效液相色谱(HPLC)技术分析了菠萝果实不同发育阶段果肉类胡萝卜素成分及含量的变化。结果表明,随着果实的成熟,两菠萝品种果肉β-胡萝卜素、玉米黄质和β-阿朴-δ’-胡萝卜醛成分均呈上升趋势,尤其是β-胡萝卜素从青果期急剧增加到完熟期,而叶黄质却呈下降趋势。两品种的β-胡萝卜素含量都显著高于其他3种色素,而且在完熟期巴厘种的β-胡萝卜素含量是卡因种的2倍以上。因此,β-胡萝卜素是造成两品种菠萝果肉类胡萝卜素积累量及外观色泽差异的主要因素之一。  相似文献   
89.
The aim of this work was to investigate the loss of freshness of fresh-cut pineapple samples stored at different temperatures using non-destructive spectroscopic methods. Three lots of fresh cut pineapples (Ananas comosus L. cv. Golden Ripe, from Costa Rica), packaged in PVC trays (250 g) were analyzed during storage at three different temperatures (5.3, 8.6 and 15.8 °C). Loss of quality of these fruit was evaluated by chemical and microbiological parameters and using NIR and MIR spectroscopy. The FT-NIR spectra were acquired in reflectance mode directly on the slice of fresh-cut pineapple, over the range 12,500–3900 cm−1, while FT-IR spectra were collected over the range 4000–700 cm−1 using an horizontal ATR cell. Some chemical and microbiological parameters were also measured. Principal component analysis (PCA) was applied to the second derivative of the spectra to uncover molecular modifications occurring over the storage time. A clear discrimination between “fresh” and “old” samples was obtained and a stability time corresponding to the time of the initial loss of freshness was defined at each temperature. The stability times revealed by NIR spectroscopy were in good accordance with those evaluated by MIR. At each temperature the stability times (i.e. the initial loss of freshness times) defined by spectroscopic techniques (4–5 d at 5.3 °C, 3–4 d at 8.6 °C and 1 d at 15.8 °C) were associated with a mesophilic bacteria count ranging between 105 and 106 CFU g−1 and lower than the maximum limit for mesophilic bacteria (<5 × 107 CFU g−1) given by French hygienic regulations at consumption.These results show that NIR and MIR spectroscopy could support conventional techniques (chemical and microbiological analysis) in studying shelf-life of fresh-cut fruit. In particular these techniques define the initial loss of freshness time, indicating a product which rapidly will be no longer acceptable if stored beyond that time. The main advantage of using IR spectroscopic techniques is to rapidly draw a profile of the product related to its change in quality.  相似文献   
90.
对12份菠萝品种的果实香气成分采用聚类分析和主成分分析方法进行多样性研究。结果表明:不同品种菠萝果实香气成分种类含量变化差异较大,聚类分析在相关系数距离19时,分为4个类群;主成分分析显示120种挥发性成分简化得到3个主成分包含27个香气成分,综合得分显示密宝菠萝最高。本研究结果可对菠萝果实香气品质进行评价,有助于加快菠萝选育种进程。  相似文献   
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