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101.
以葡萄6个不同果形品种盛花期花序为材料,通过荧光定量PCR方法分析比较葡萄IQ67结构域(IQ67 domain, IQD)基因家族成员VvIQD10的表达;从椭圆形葡萄品种‘天山’中克隆出VvIQD10基因编码区序列,对其进行生物信息学分析,采用亚细胞定位瞬时表达载体转化烟草的方法研究VvIQD10蛋白在细胞中的分布情况,并通过酵母双杂交实验和双分子荧光互补试验进行蛋白互作研究。结果表明:(1)VvIQD10基因在长果形葡萄品种中的表达量高于近圆形葡萄品种。(2)VvIQD10基因开放阅读框长度为1 401 bp,编码466个氨基酸。(3)VvIQD10蛋白为不稳定亲水性蛋白,无信号肽和跨膜区,但含保守的IQ67结构域,主要结构为α螺旋和随机卷曲,与猕猴桃IQD家族成员(PSS09955.1)亲缘关系最为接近。(4)VvIQD10蛋白主要定位于微管和质膜,并且直接与细胞骨架组织相关蛋白——钙调素类蛋白(VvCML)相互作用。研究认为,VvIQD10基因可能参与葡萄果形调控,葡萄VvCML蛋白从胞质到微管的募集依赖于VvIQD10,推测VvIQD10蛋白可能通过和钙调素类蛋白相结合来调控细胞骨架运动,进而参与葡萄果实形状的变化。  相似文献   
102.
Two 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) genes have been cloned from RNA isolated from leaf tissue of apple (Malus domestica cv. Royal Gala). The genes, designated MD-ACO2 (with an ORF of 990 bp) and MD-ACO3 (966 bp) have been compared with a previously cloned gene of apple, MD-ACO1 (with an ORF of 942 bp). MD-ACO1 and MD-ACO2 share a close nucleotide sequence identity of 93.9% in the ORF but diverge in the 3′ untranslated regions (3′-UTR) (69.5%). In contrast, MD-ACO3 shares a lower sequence identity with both MD-ACO1 (78.5%) and MD-ACO2 (77.8%) in the ORF, and 68.4% (MD-ACO1) and 71% (MD-ACO2) in the 3′-UTR. Southern analysis confirmed that MD-ACO3 is encoded by a distinct gene, but the distinction between MD-ACO1 and MD-ACO2 is not as definitive. Gene expression analysis has shown that MD-ACO1 is restricted to fruit tissues, with optimal expression in ripening fruit, MD-ACO2 expression occurs more predominantly in younger fruit tissue, with some expression in young leaf tissue, while MD-ACO3 is expressed predominantly in young and mature leaf tissue, with less expression in young fruit tissue and least expression in ripening fruit. Protein accumulation studies using western analysis with specific antibodies raised to recombinant MD-ACO1 and MD-ACO3 produced in E. coli confirmed the accumulation of MD-ACO1 in mature fruit, and an absence of accumulation in leaf tissue. In contrast, MD-ACO3 accumulation occurred in younger leaf tissue, and in younger fruit tissue. Further, the expression of MD-ACO3 and accumulation of MD-ACO3 in leaf tissue is linked to fruit longevity. Analysis of the kinetic properties of the three apple ACOs using recombinant enzymes produced in E. coli revealed apparent Michaelis constants (Km) of 89.39 μM (MD-ACO1), 401.03 μM (MD-ACO2) and 244.5 μM (MD-ACO3) for the substrate ACC, catalytic constants (Kcat) of 6.6 × 10−2 (MD-ACO1), 3.44 × 10−2 (Md-ACO2) and 9.14 × 10−2 (MD-ACO3) and Kcat/Km (μM s−1) values of 7.38 × 10−4 μM s−1 (MD-ACO1), 0.86 × 10−4 M s−1 (MD-ACO2) and 3.8 × 10−4 μM s−1 (MD-ACO3). These results show that MD-ACO1, MD-ACO2 and MD-ACO3 are differentially expressed in apple fruit and leaf tissue, an expression pattern that is supported by some variation in kinetic properties.  相似文献   
103.
This study reports the rate of fruit phenological pattern of Musanga leo-errerae and how it sustains the chimpanzee population better than other fruits in Kalinzu Forest Reserve. We analysed 2635 faecal samples to determine the proportion of M. leo-errerae by composition of fruit diet compared with other fruits eaten by chimpanzees. Musanga leo-errerae trees were monitored for fruit production between November 2002 and December 2004. Musanga leo-errerae fruit production did not vary significantly between months (ANOVA, F  = 2.0, d.f. = 11, P  = 0.13). The size of fruit and rate maturation varied with seasons, although fruit production was synchronous and available all year round. From the 2635 faecal samples analysed, 79.2% contained M. leo-errerae fruit seed. Chimpanzee diet in Kalinzu is 75% frugivorous, 37.2% of which is solely contributed by M. leo-errerae fruit. The continuous availability of M. leo-errerae fruit makes it the most important food for chimpanzees in this forest, especially during general fruit scarcity there by joining figs in importance for chimpanzee survival in tropical Africa.  相似文献   
104.
In this work, five expansin cDNAs (DlExp15) from ‘Shijia’ longan fruit were isolated and characterized. Moreover, the expression profiles of five expansin genes and the effect of naphthalene acetic acid (NAA) and thidiazuron (TDZ) on their expressions were investigated. The results showed that five expansins exhibited different expression patterns during fruit growth and development. DlExp1 was constitutively expressed in the pericarp while the levels of DlExp1 mRNA in the aril were very high at early stage of fruit development, and decreased gradually from 28 to 77 days after anthesis (DAA). DlExp2 and DlExp4 were related to the growth of pericarp, whereas the expression of DlExp2 and DlExp5 in the aril decreased from 28 to 77 DAA. In addition, NAA and TDZ applied at the stage of rapid pericarp (21 DAA) or aril growth (56 DAA) increased the accumulations of DlExp1 and DlExp2 mRNA in the pericarp and aril, while NAA and TDZ had no or little effect on the accumulations of DlExp3, DlExp4 and DlExp5. DlExp1 and DlExp2 also accumulated highly in rapidly growing tissues, such as young stems and leaves. These findings indicated that Exp genes played a different role in longan fruit growth and showed different response to plant growth substances.  相似文献   
105.
Since October 2006, the US Department of Agriculture–Agricultural Research Service (USDA–ARS) has been implementing a fruit fly liquid larval diet technology transfer, which has proceeded according to the following steps: (1) recruitment of interested groups through request; (2) establishment of the Material Transfer Agreement with agricultural research service; (3) fruit fly liquid larval diet starter kit sent to the requestor for preliminary evaluation; (4) problem‐solving through email or onsite demonstration; (5) assessment on feedback from the participants to decide whether to continue the project. Up to date, the project has involved 35 participants from 29 countries and 26 species of fruit flies. Fourteen participants have concluded their evaluation of the process, and 11 of these 14, have deemed it to be successful. One participant has decided to implement the project on a larger scale. The 14 participants were, Argentina (Ceratitis capitata and Anastrepha fraterculus), Bangladesh (Bactrocera cucurbitae, C. capitata, and Bactrocera dorsalis), China (Fujia province) (B. dorsalis), Italy (C. capitata), Fiji (Bactrocera passiflorae), Kenya (Bactrocera invadens, Ceratitis cosyra), Mauritius (Bactrocera zonata and B. cucurbitae), Mexico (Anastrepha species), Philippines (Bactrocera philippinese), Thailand (Bactrocera correcta), Austria (C. capitata, Vienna 8 and A. fraterculus), Israel (Dacus ciliatus and C. capitata), South Africa (C. capitata, Vienna 8) and Australia (C. capitata). The Stellenbosch medfly mass‐rearing facility in South Africa and the CDFA in Hawaii were two mass‐scale rearing facilities that allowed us to demonstrate onsite rearing in a larger scale. Demonstrations were performed in CDFA in 2007, and in Stellenbosch, South Africa in 2008; both were found to be successful. The Stellenbosch medfly mass‐rearing facility in South Africa decided to adopt the technology and is currently evaluating the quality control of the flies that were reared as larvae on a liquid diet.  相似文献   
106.
The sterile insect technique (SIT) is widely used to suppress or eradicate infestations of the Mediterranean fruit fly, Ceratitis capitata (Wied.), an insect whose broad polyphagy poses a serious threat to fruit and vegetable crops. The SIT involves the production, sterilization and release of sterile insects to obtain sterile male by wild female matings, thus yielding infertile eggs. Mass‐rearing over many generations is known to produce dramatic changes in the behaviour and life history of C. capitata. This study investigated the possibility that mass‐rearing also alters male response to trimedlure, a sex‐specific attractant widely used in detection and monitoring programmes. We compared captures of released males from a mass‐reared strain and a recently established colony of wild flies in trimedlure‐baited Jackson traps at three spatial scales – open field, large field enclosures (75 m2) and small field cages (7 m2) – in two separate years. In the first year, males were used independently of flight ability, while in the second year only males with demonstrated flight capability were used. Trap capture was scored 2 days after release for the open field and the large field enclosures but either 1 h or 1 day after release in the small field cages. The findings were consistent across these different experiments: wild‐like males were captured in significantly greater numbers than mass‐reared males in both years of study, except in the trials lasting 1 day in the small field cages where significantly more wild than mass‐reared males were captured in 1 year but not the other. These results are compared with other studies, and their implications for SIT are discussed.  相似文献   
107.
Essential oils from the dried aerial parts of Limnophila geoffrayi Bonati were obtained by water-distillation. d-Pulegone (27.14%), perillaldehyde (19.13%) and limonene (9.00%) were characterized as the major constituents using gas chromatography-mass spectrometry analysis. The antimicrobial activities of the essential oils and their major components were evaluated against microorganisms encountered normally in contaminated cosmetic products, using the agar- and broth-dilution methods. Their insecticidal activities against the Oriental fruit fly Bactrocera dorsalis (Hendel) were tested using a bioassay with impregnated filter paper. The results showed that the essential oils possessed high antimicrobial activity, with minimum inhibitory concentrations ranging from 0.03 to 0.2% per unit volume (v/v). Strong insecticidal activity as a fumigant was also observed at an oil dose of 5 μl/disc, with a 94% mortality. Perillaldehyde was the most active compound among the main components of these essential oils.  相似文献   
108.
Full appreciation of the roles of the plant cuticle in numerous aspects of physiology and development requires a comprehensive understanding of its biosynthesis and deposition; however, much is still not known about cuticle structure, trafficking and assembly. To date, assessment of cuticle organization has been dominated by 2D imaging, using histochemical stains in conjunction with light and fluorescence microscopy. This strategy, while providing valuable information, has limitations because it attempts to describe a complex 3D structure in 2D. An imaging technique that could accurately resolve 3D architecture would provide valuable additions to the growing body of information on cuticle molecular biology and biochemistry. We present a novel application of 3D confocal scanning laser microscopy for visualizing the architecture, deposition patterns and micro-structure of plant cuticles, using the fluorescent stain auramine O. We demonstrate the utility of this technique by contrasting the fruit cuticle of wild-type tomato ( Solanum lycopersicum cv. M82) with those of cutin-deficient mutants. We also introduce 3D cuticle modeling based on reconstruction of serial optical sections, and describe its use in identification of several previously unreported features of the tomato fruit cuticle.  相似文献   
109.
110.
研究不同温度对采后石榴品种‘净皮甜’果实品质和某些生理指标影响的结果表明:在5℃条件下贮藏的石榴,其果实中可溶性固形物含量、总糖含量和可滴定酸含量可以得到保持,果皮的相对电导率和褐变指数升高速率减慢,果实的呼吸速率和腐烂率下降,抗坏血酸氧化酶(AAO)和多酚氧化酶(PPO)活性受到抑制,过氧化物酶(POD)和过氧化氢酶(CAT)活性保持相对较高水平。贮藏120d的果实品质良好,保鲜效果也较好。  相似文献   
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