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41.
Polysaccharide components present in the pseudo-stem (scape) of M. paradisiaca were purified from acetone powder of the scape
by delignification followed by extraction with aqueous solvents into water soluble polysaccharide (WSP), EDTA-soluble polysaccharide
(EDTA-SP), alkali-soluble polysaccharide (ASP) and alkali-insoluble polysaccharide (AISP) fractions. Sugar compositional analysis
showed that WSP and EDTA-SP contained only D-Glc whereas ASP contained D-Glc, L-Ara and D-Xyl in ∼ 1:1:10 ratio, respectively,
and AISP' contained D-Glc, L-Ara and D-Xyl in ∼ 10:1:2 ratio, respectively. WSP was further purified by complexation with
iso-amylalcohol and characterized by specific rotation, IR spectroscopy, Iodine affinity, ferricyanide number, blue value,
hydrolysis with α-amylase and glucoamylase, and methylation linkage analysis, and shown to be a amylopectin type α-D-glucan.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
42.
43.
The role of bats and sunbirds in the pollination ecology of Musa itinerans Cheesman (Musaceae) was studied in the tropical seasonal rain forests of Xishuangbanna, southern Yunnan, China. It was found that both long–tongued fruit bats (Macroglossus sobrinus) and sunbirds (Arachnothera longirostris) were effective pollinators of M. itinerans. Nectar production had two peaks, one during the day and one during night (0800–1200 h and 2000–2400 h), which allowed the two different foragers to visit at specific times. The visitation patterns of the two foragers coincided with both flowering time and nectar production. By measuring the differences in fruit weight and seed production among different bagging experiments, we found that birds and bats were equally effective as pollinators of this species. 相似文献
44.
Effect of arbuscular mycorrhizal fungi on the acclimatization of micropropagated banana plantlets 总被引:1,自引:0,他引:1
A. M. Yano-Melo L. C. Maia O.J. Saggin Jr. J. M. Lima-Filho N. F. Melo 《Mycorrhiza》1999,9(2):119-123
The effect of arbuscular mycorrhizal fungi (AMF) on micropropagated banana plantlets was evaluated during the acclimatization
period. Plants were inoculated with Acaulospora scrobiculata, Glomus clarum or Glomus etunicatum. After cultivation in a greenhouse for 3 months, height, leaf area, fresh weight and dry matter of root and shoots, level
of AMF colonization, nutrient level, photosynthesis and transpiration rate, water potential and stomatal conductance were
measured. The number of AMF spores produced in each treatment was also determined. Plantlets inoculated with AMF had greater
height, leaf area and fresh weight of shoots and roots, as well as higher rates of photosynthesis and transpiration than controls.
Plants inoculated with Glomus were superior in most of the evaluated parameters.
Accepted: 24 May 1999 相似文献
45.
Crouch J.H. Crouch H.K. Constandt H. Van Gysel A. Breyne P. Van Montagu M. Jarret R.L. Ortiz R. 《Molecular breeding : new strategies in plant improvement》1999,5(3):233-244
Progress in the breeding of plantain and banana has been restricted by the complex genetic structure and behaviour of cultivated
polyploid Musa. Genetic improvement has been hindered due to the large amount of space required for growth and maintenance
of plant populations, in addition to the long growth cycle and the low levels of fertility and seed viability characteristic
of cultivated genotypes. Molecular marker assisted breeding has the potential to dramatically enhance the pace and efficiency
of genetic improvement in Musa. This study was conducted to compare different PCR-based marker systems (RAPD, VNTR and AFLP)
for the analysis of breeding populations generated from two diverse Musa breeding schemes. All three assays detected a high
level of polymorphism between parental genotypes and within progeny populations. As expected, AFLP assays had by far the highest
multiplex ratio while VNTR analysis detected the highest levels of polymorphism. AFLP analysis of a full-sib tetraploid hybrid
population confirmed previous reports based on VNTR analysis, of a high frequency of recombination during 2n (3x) gamete formation
by a triploid plantain landrace. In addition, both VNTR and RAPD analyses of a full-sib triploid hybrid population suggested
a high frequency of homoeologous recombination during n (2x) gamete formation by tetraploid hybrids. In general, there was
a poor correlation between estimates of genetic similarity based on different types of marker. The implications of these findings
for the molecular breeding of Musa crops are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
46.
H. K. BUHARIWALLA R. L. JARRET B. JAYASHREE J. H. CROUCH R. ORTIZ 《Molecular ecology resources》2005,5(2):327-330
This is the first report of targeted development of B genome microsatellite markers in Musa. A total of 44 sequences with microsatellites were isolated from an enriched library of Musa balbisiana cv. ‘Tani’ (BB genome). Of these, 25 were polymorphic when screened on 14 diverse diploid and triploid Musa accessions. The number of alleles detected by each marker ranged between one and seven. All 25 microsatellite markers generated amplification products in all species and genome complements. These new microsatellite markers fill an important gap for diversity assessment and linkage mapping studies in plantain (AAB) and cooking banana (ABB). 相似文献
47.
Biological control of crown rot of bananas with Pichia anomala strain K and Candida oleophila strain O 总被引:1,自引:0,他引:1
The antagonistic activity of two yeast strains (Pichia anomala (E.C. Hansen) Kurtzman, strain K and Candida oleophila Montrocher, strain O) against the parasitic complex responsible for banana crown rot was evaluated. The strains were applied at three different concentrations (106, 107, 108 cfu/ml) and their efficacy tested in vivo on three separate fungi (Colletotrichum musae (Berk. & Curt.) Arx, Fusarium moniliforme Sheldon, and Cephalosporium sp.) and on a parasitic complex formed by association of these three fungi. At the concentrations used C. musae appeared to be the most pathogenic. The complex showed intermediate aggressiveness between C. musae and both other fungi.Statistically significant antagonistic effects were observed on C. musae, F. moniliforme, and the fungal complex. The highest protection level (54.4%) was observed with strain O added at 108 cfu/ml on crowns previously inoculated with the fungal complex. The level was lower when the fungi were inoculated separately.Furthermore, the antagonistic effect was strongly reinforced when strain O at 108 cfu/ml was applied 24 h before fungal complex inoculation (59.9%), as compared to its application 15 min (24.3%) or 3 h (27.3%) after fungal complex inoculation. Bananas showed increased susceptibility to the fungal complex from March to June, and this influenced the level of protection by yeast, which decreased over the same period. A strict negative correlation (R2 = 0.83) was highlighted between susceptibility of banana to crown rot and protection provided by yeast. 相似文献
48.
Markku HKKINEN 《植物分类学报》2009,47(1)
The center of diversity of the genus Musa (Musaceae) is in Southeast Asia, a region not studied in detail and where new species and varieties continue to be reported. A new wild banana species, M. chunii Hakki-nen from Yunnan, China is described and illustrated based on observed morphological characteristics in the field. This extremely rare new species was only found in Tongbiguan Nature Reserve, Dehong District, West Yunnan. A key to M. chunii and related taxa is provided. In addition, critical notes regarding M. rubra Kurz identity are given. 相似文献
49.
50.
L-Nucleosides as chemotherapeutic agents 总被引:7,自引:0,他引:7
A genetic transformation system has been developed for three Mycosphaerella pathogens of banana and plantain (Musa spp.). Mycosphaerella fijiensis and Mycosphaerella musicola, the causal agents of black and yellow Sigatoka, respectively, and Mycosphaerella eumusae, which causes Septoria leaf spot of banana, were transformed with a construct carrying a synthetic gene encoding green fluorescent protein (GFP). Most single-spored transformants that expressed GFP constitutively were mitotically stable in the absence of selection for hygromycin B resistance. Transformants of all three species were pathogenic on the susceptible banana cultivar Grand Nain, and growth in planta was comparable to wild-type strains. GFP expression by transformants allowed us to observe extensive fungal growth within leaf tissue that eventually turned necrotic, at which point the fungi grew saprophytically on the dead tissue. Leaf chlorosis and necrosis were often observed in advance of saprophytic growth of the mycelium on necrotic tissue, which supports previous reports suggesting secretion of a phytotoxin. 相似文献