红掌茎基腐病病原鉴定

 1996～1997年云南省热带作物科学研究所1～2年生地栽红掌发生了严重的茎基腐病,致使根、茎、叶柄变褐,叶片黄化,叶柄脱落,植株枯死。从病组织和土壤基质中分别分离到40和33个分离物,经鉴定寄生疫霉Phytophthora parasitica,光孢镰刀菌Fusariumoxyspo-rum为红掌茎基腐的致病菌。     

红掌花叶病病原鉴定及检测方法的建立

以红掌为材料,利用RT-PCR方法鉴定出红掌花叶病的一种病原--芋花叶病毒（Dasheen mosaic virus,DMV）,并建立了该病毒的RT-PCR检测方法.依据该方法,将从0.1 g染病组织中提取的总RNA稀释500倍,仍能从中检测出DMV的存在,说明该方法的灵敏度高.该检测方法的建立,为红掌栽培,尤其是工厂化生产红掌无毒种苗提供了技术支持.     

盆栽红掌亚丽桑娜催花技术研究

[目的]探讨喷施不同浓度的磷酸二氢钾和6-苄基嘌呤对亚丽桑那盆栽苗的催花效果。[方法]以亚丽桑那组培穴盘苗为供试材料,喷施不同浓度的磷酸二氢钾和6-苄基嘌呤对亚丽桑那盆栽苗进行催花试验,测量亚丽桑那植株的花芽分化数、叶片数、花枝直径、花掌长度等生物学性状,研究不同药剂处理对亚丽桑那盆栽苗的催花效果。[结果]喷施3mg／L的磷酸二氢钾可促进亚丽桑那组培苗提早开花;3mg／L磷酸二氢钾＋20mg／L6-苄基嘌呤的处理效果最好,花芽分化早、多,成花率高达90％,花枝长且粗壮;当6-苄基嘌吟浓度为40mg／L时,亚丽桑那盆栽苗生长受抑制;6-苄基嘌呤对亚丽桑那盆栽苗的叶片黄化有一定的抑制作用。[结论]该试验获得了提高红掌盆栽质量和开花整齐度的技术,提高了国产红掌盆花的规模化种植水平。     

西花蓟马对安祖花组培苗及其移栽苗危害的初步研究

以安祖花品种沙瑞德组培苗为试材,研究了西花蓟马对安祖花组培苗的危害。结果表明:西花蓟马可侵入培养瓶中,吸食组培苗茎尖与叶片,严重抑制组培苗生长,并传播病菌引起二次污染。     

外源茉莉酸对高温胁迫下的红掌幼苗的影响

研究了外源茉莉酸对高温胁迫下红掌幼苗叶片热致死时间、膜质过氧化以及抗氧化物酶活性的影响。结果表明：1mmol/L的外源JA可以最大限度地提高38℃高温胁迫下的红掌叶片的热致死时间;外施JA可以提高高温胁迫下的红掌叶片的POD活性、SOD活性;降低MDA和O2－-含量;不同时间高温锻炼下可以提高红掌叶片内源JA 浓度。结合以前的试验结果推测： JA可能是通过提高抗氧化物酶活性,降低体内MDA和O2－-含量来缓解高温胁迫对红掌幼苗的生长发育的影响。     

Epidemiological evidence for the emergence of a new pathogenic variant of Ralstonia solanacearum in Martinique (French West Indies)

The emergence of a new genotype and pathogenic variant of Ralstonia solanacearum in Martinique is described. Bacterial wilt of solanaceous crops caused by phylotype‐I and ‐II strains (‘historical strains’), was reported in Martinique in the 1960s. From 1999, Anthurium and cucurbit production was strongly affected by strains described as a new pathogenic variant genotyped phylotype IIB/sequevar4NPB (phIIB/4NPB). The following questions concerning these strains were investigated: (i) were they introduced or endemic, (ii) was their distribution widespread in Martinique, and (iii) which factors could explain this emergence? This study examined 221 isolates collected from 1989 to 2003 after several surveys. The main survey (2002–03) included 115 vegetable and ornamental crop farms. From 1999 to 2001, these phIIB/4NPB strains were initially described as the ‘Anthurium‐cucurbit’ strain. In 2003, they made up one‐third of the isolates recovered from solanaceous hosts, particularly tomato. This pathogenic variant of R. solanacearum was consistently recovered from wild species and several weeds throughout Martinique, suggesting that these strains were well established in Martinique. Data reported are consistent with the emergence of a new population of R. solanacearum in Martinique, which has spread rapidly across the entire island and may overtake the previously established population, particularly on tomatoes. Evidence is presented which suggests that the emergence of these new strains is more frequent on vegetable crops when cucurbitaceous and musaceous plants are grown in succession.     

提高红掌叶片愈伤组织诱导和植株分化及壮苗率的技术研究

研究了不同培养基、糖类、培养条件及活性炭对红掌幼嫩叶片愈伤组织诱导和植株分化及壮苗率的影响。结果表明：在改良MS+6-BA1.0mg/l+2,4-D0.1mg/l,添加葡萄糖30g/l和暗培养,可获得较高的愈伤组织诱导率;在继代培养中添加活性炭1.0g/l,有利于提高幼芽分化和壮苗率。各个品种间的愈伤组织诱导率与植株分化率有一定差别。红掌组培苗无需另行作生根培养即可获得较为健壮的小苗,移栽成活率可达95%以上。     

红掌叶片离体培养过程中内源激素含量的变化

应用酶联免疫吸附测定法(ELISA)研究了红掌叶片愈伤组织诱导和植株再生过程中内源激素的含量变化。结果表明:内源激素IAA,GA3,ABA,ZR在幼嫩叶片内的含量均较高;而在愈伤组织诱导阶段,4种内源激素均呈下降趋势;在植株再生过程中,内源IAA和GA3含量继续下降,ABA和ZR含量的变化因品种而异,粉冠军内源含量开始回升,亚历桑娜则继续下降至最低水平;在小苗移栽后,粉冠军的4种内源激素含量均急剧回升并保持较高水平,亚历桑娜中内源IAA和GA3含量继续下降至最低水平,而内源ABA和ZR含量回升保持较高水平。     

红掌种质资源表型性状的遗传多样性研究

[目的]研究红掌种质资源的遗传多样性,为红掌的种质创新和杂交育种提供依据。[方法]利用形态学标记对46个红掌种质资源的36个形态学性状进行研究。[结果]46个红掌品种的遗传多样性丰富,遗传变异系数为0.24~0.36,遗传多样性指数为0.343 8~2.111 9。其中,佛焰苞长的变异系数最大,为0.36;佛焰苞颜色遗传多样性指数最大,为2.111 9。UPGMA聚类分析表明,这46个红掌品种可划分为4大类,包括3个较小的类群和1个较大的类群。[结论]该研究中应用的一些形态学标记对于红掌品种鉴定、遗传多样性分析和杂交育种具有重要的应用价值。     

红掌叶片愈伤组织诱导与植株再生的优化

以亚丽桑娜红掌(Anthurium andraeanum cv.Arizona)为研究对象,研究了不同激素配比对愈伤组织诱导、不定芽分化、芽增殖培养、生根培养等方面的影响。结果表明,培养基MS+6-BA 2.0 mg/L+2,4-D 0.2 mg/L为愈伤组织诱导的最适培养基;培养基MS+6-BA 1.0 mg/L+6-KT 1.5 mg/L为不定芽分化的最适培养基;培养基MS+6-BA 0.8 mg/L为继代培养的最佳培养基;培养基MS+NAA 0.3 mg/L+IBA0.2 mg/L为诱导生根的最佳培养基。