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1.
Triterpenic saponins isolated from seeds of Madhuca indica and fruit pericarp from Sapindus mukorossi exhibited inhibitory effect against two phyto-parasitic nematodes. Azadirachtin and salanin-nimbin-desacetylnimbin (SND) was extracted from seeds and oil of Azadirachta indica A. Juss, respectively. M. indica and S. mukorossi saponins were found to inhibit the movement of pre-adult (J4) stage of Rotylenchulus reniformis with LC50 of 168.8 and 181.9 µg/mL. Azadirachtin and SND affected the mobility of secondary juvenile stage (J2) of Meloidogyne incognita by 83.3 and 80.1% respectively, at 0.5 mg m/L. M. indica saponin (LC50 220 µg/mL) exhibited a potentiation effect in the presence of azadirachtin in a 1:3 ratio (LC50 120.1 µg/mL). A binary mixture (1:1) of azadirachtin and SND was found to show significant nematicidal activity against M. incognita (LC50 70.9 µg/mL) and R. reniformis (LC50 91.2 µg/mL).  相似文献   

2.
Background: The South Aegean Volcanic Arc (SAVA), one of the most notable geological structures of the Mediterranean Sea, is floristically well known. Nevertheless, the factors that contribute to shaping the plant species richness of the SAVA remain unclear.

Aims: To investigate the factors that affect plant species richness and identify plant diversity hotspots in the SAVA and other central Aegean islands.

Methods: We used stepwise multiple regression to test the relationship between a number of environmental factors and plant species richness in the SAVA, as well as the residuals from the species–area linear regressions of native, Greek and Cycladian endemic taxa as indicators of relative species richness.

Results: The area was confirmed to be the most powerful single explanatory variable of island species richness, while geodiversity, maximum elevation and mean annual precipitation explained a large proportion of variance for almost all the species richness measures. Anafi, Amorgos and Folegandros were found to be endemic plant diversity hotspots.

Conclusions: We have demonstrated that geodiversity is an important factor in shaping plant species diversity in the Cyclades, while mean annual precipitation, human population density and maximum elevation were significant predictors of the Greek endemics present in the Cyclades. Finally, Anafi was found to be a plant diversity hotspot in the South Aegean Sea.  相似文献   

3.
Barium chloride at 0.1 mM concentration inhibited elongation of mungbean (Phaseolus aureus) roots more strongly than elongation of hypocotyls. Root growth was completely inhibited at 80 mM and there was no germination at 100 mM. Respiration rates which were directly proportional to seedling vigour declined at varying degrees at the growth-inhibitory concentrations of BaCl2. Barium retarded senescence in isolated leaf discs ofCephalandra indica by maintaining the chlorophyll level in darkness. The carotenes were similarly protected from degradation by Ba in darkness whereas xanthophylls were retained both in darkness and light. Ba also protected anthocyanin pigments in the staminode discs ofCanna indica flowers and reduced to a variable extent the leakage of betacyanin pigment fromBeta vulgaris root discs caused by various membrane active chemicals. Applied either alone or in combination with IAA, Ba inhibited cell enlargement in wheat (Triticum aestivum) coleoptile sections. Barium-induced inhibition of lettuce (Lactuca sativa) hypocotyl elongation was largely overcome by GA3.  相似文献   

4.
Genetic transformation of rice (Oryza sativa L.) mediated by Agrobacterium ttumefaciens has been confirmed for japonica varieties and extended to include the more recalcitrant indica varieties. Immature embryos were inoculated with either A. tumefaciens At656 (pCNL56) or LBA4404 (pTOK233). Experimental conditions were developed initially for immature embryos treated with strain At656, based upon both transient and stable -glucuromdase (GUS) activities. However, plant regeneration following selection on G418 (pCNL56 contained the nptII gene) did not occur. Using the same basic protocol, but inoculating immature embryos of rice with LBA4404 (pTOK233), resulted in efficient (about 27%) production of transgenic plants of the japonica variety, Radon, and an acceptable efficiency (from 1–5%) for the indica varieties IR72 and TCS10. Transformation was based upon resistance to hygromycin (pTOK233 contains the hpt gene), the presence of GUS activity (from the gusA gene), Southern blots for detection of the integrated gusA gene, and transmission of GUS activity to progeny in a Mendelian 3:1 segregation ratio. Southern blots indicated two to three copies of the gene integrated in most transformants. Transgenic plants of both the japonica and indica varieties were self-fertile and comparable in this respect to seed-grown plants. Key factors facilitating the transformation of rice by Agrobacterium tumefaciens appeared to be the use of embryos as the expiant, the use of hygromycin as the selection agent (which does not interfere with rice regeneration), the presence of extra copies of certain vir genes on the binary vector of pTOK233, and maintaining high concentrations of acetosyringone for inducing the vir genes during co-cultivation of embryos with Agrobacterium.Abbreviations AS acetosyringone - DMRT Duncan's Multiple Range Test - GUS -glucuronidase - T-DNA transferred DNA We wish to thank Dr. Toshihiko Komari, Japan Tobacco Inc. for providing Ayrobacterium tumefaciens strain LBA4404 (pTOK322). Support by the Rockefeller Foundation in the form of a fellowship to R.R.A. and a grant to T.K.H. is acknowledged. This is journal paper number 14,914 from the Purdue University Agricultural Experiment Station.  相似文献   

5.
We developed eight polymorphic microsatellite loci in Indian neem (Azadirachta indica var. indica) and cross-amplified in closely related species Thai neem (A. indica var. siamensis). The number of alleles per locus in Indian neem and Thai neem ranged from 3 to 9 and 3 to 9, respectively. Average observed and expected heterozygosities in Indian neem and Thai neem were 0.63 and 0.70 and 0.61 and 0.65, respectively. Two loci exhibited significantly fewer heterozygotes than expected under Hardy–Weinberg equilibrium. These microsatellites may provide a useful tool for population genetics to establish conservation and management strategy.  相似文献   

6.
A tissue culture system for different germplasms of indica rice   总被引:4,自引:0,他引:4  
Ge X  Chu Z  Lin Y  Wang S 《Plant cell reports》2006,25(5):392-402
Agrobacterium-mediated transformation of indica rice has been manipulated in only a limited number of cultivars because the majority of indica varieties are recalcitrant to in vitro response. Establishment of a highly efficient and widely used tissue culture system for indica rice will accelerate the application of transformation technology in breeding programs and the study of the functions of indica-specific genes. By manipulating plant growth regulators, organic components and salts within the culture media, we established two media for callus induction and subculture, respectively, in tissue culture of indica rice. The modified media could guarantee the production and proliferation of a great number of embryogenic calli with high regeneration capacity from mature seeds representing different indica rice germplasms. The calli obtained from this system should be ideal material for Agrobacterium-mediated transformation. The results suggest that this optimized tissue culture system will be widely applicable for the tissue culture of indica varieties. Electronic Supplementary Material Supplementary material is available for this article at The first two authors contributed equally to this work.  相似文献   

7.
Summary The relative body water conservation efficiency of two Indian desert gerbil species,Meriones hurrianae (diurnal/crepuscular) andTatera indica (nocturnal), has been examined under near-natural conditons in different seasons.A mean urine osmolarity of 3180 mosmol/l (maximum 4645 mosmol/l) inM. hurrianae and a mean value of 5128 mosmol/l (maximum 7547 mosmol/l) inT. indica have been recorded during summer.Urine osmolarity and urea levels indicated that whileM. hurrianae remain sufficiently hydrated mainly by virtue of their feeding habit,Tatera indica may depend on the relatively higher concentrating capacity of their kidneys.  相似文献   

8.
Protoplasts of the indica rice (Oryza sativa L.) variety, IR54, were transiently transformed with the gusA gene and stably transformed with both the neo and gusA genes. We show that PEG-mediated co-transformation of protoplasts with two genes on separate plasmids coupled with selection on kanamycin is an effective way of transferring foreign gene(s) into the indica rice genome. The efficiency of co-transformation was generally 20–30%, i.e. the frequency of kanamycin-resistant calli having both the neo and gusA active genes. Southern blot analysis using a probe for gusA indicated integration of several copies of the gene, often as head to tail tandem repeats.Abbreviations GUS ß-glucuronidase - PEG polyethlene glycol - PCV packed cell volume  相似文献   

9.
Efficient vesicular arbuscular mycorrhizal (VAM) fungi were screened and selected for a slow-growing forest tree species,Tamarindus indica L., important in tropical forestry. Seedlings were inoculated with 13 different VAM fungi, obtained from various sources around the world. Inoculated plants had greater plant height, leaf number, stem girth, biomass, phosphate and Zn2+ content. They also had higher amounts of mycorrhizal spores, per cent root colonization and external hyphae, as measured by per cent soil aggregation.Tamarindus indica seedlings responded best to inoculation withGigaspora margarita (ICRISAT) followed byGlomus fasciculatum.
Résumé On a testé et sélectionné des moisissures mycorrhizales (VAM) vésiculaires, arbusculaires efficaces pour une espèce d'arbre forestier à croissance lente,Tamarindus indica L., importante en foresterie tropicale. On a inoculé des semences avec 13 moisissures VAM différentes, obtenues de diverses sources de par le monde. Les plants inoculés sont plus hauts, ont un nombre de feuilles et une circonférence de tronc plus élevés et un contenu plus élevé en biomasse, phosphate et Zn2+. Ils ont aussi une quantité plus élevée de spores mycorrhizales, une colonisation d'un pourcentage plus élevé de racines et d'hyphes externes, mesurés par le pourcentage d'aggrégation du sol. Les semences deTamarindus indica répondent le mieux à l'inoculation deGigaspora margarita ICRISAT suivi de celle deGlomus fasciculatum.
  相似文献   

10.
Microsatellite markers for mango (Mangifera indica L.) were developed using a genomic library enriched for (GA)n and (GT)n dinucleotide repeats. A subset of 41 positive clones was sequenced and primers were designed. Twenty‐eight primer pairs produced polymorphic amplification products for a diversity sample including 15 mango cultivars and two accessions from the related species Mangifera laurina and Mangifera applanata. Nineteen simple sequence repeat (SSR) loci with clear scorable patterns were chosen to study diversity in the mango germplasm bank of Guadalupe (FWI). The number of alleles ranged from three to 13 with observed levels of heterozygosity ranging from 0.059 to 0.857.  相似文献   

11.
The concomitant production of formic acid and pterin compounds from guanosine-5′-triphosphate (GTP) has been found in cell-free extracts of Serratia indica. Among the pterin compounds, l-threo-neopterin–the major Crithidia factor in S. indica–, a cyclic phosphate of neopterin (cNP), d-erythro-neopterin and 6-hydroxymethyl pterin were detected and isolated. Formate-14C elimination from GTP-8-14C was quantitatively distributed in the ethyl acetate layer in the ehyl acetate-hydrochloric acid partition system. Carbon 8 of GTP was released as formic acid. Enzymatic production of formate and cNP was linear for 2 hr at 37°C. Formate production was proportional to the enzyme concentration. The optimum pH for formate elimination was observed around pH 8.6. Optimum temperature for the production of formate and cNP was 50°C. The apparent Km value of GTP for formate production was 6.2×10?bm. Formate eliminating activity was activated by disodium phosphate but was inhibited by Mg2+ or AMP. Incorporation of GTP-U-14C into pterin compounds was also regulated with disodium phosphate. Effective incorporation into cNP and d-erythro-neopterin occurred in the presence of phosphate. When phosphate was omitted from the system, however, effective incorporation into 6-hydroxymethyl pterin was observed. The biosynthetic process of the Crithidia factors, i.e. l-threo-neopterin and cNP, from GTP in S. indica is also discussed.  相似文献   

12.
13.
Four yeast strains (APSS 805, APSS 806, APSS 815 and AP-18) belonging to a novel Torulaspora species were isolated from coal mine soils of Singareni in Andhra Pradesh state, India. Another strain (PBA-22) was isolated from agricultural field soil from Gujarat state, India. The vegetative cells of all these strains were round, haploid and produced asci by conjugation between independent cells or mother cell and bud, with rough ascospores, suggesting their possible relation to ascomycetous yeast genus Torulaspora. Phylogenetic analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and Internal Transcribed Spacer (ITS) regions revealed that, among the five strains, three viz. APSS 805, APSS 806 and APSS 815 have identical sequences. The other two strains (AP-18 and PBA-22) differed from the other three strains in less than 1% nucleotide substitutions in the combined D1/D2 domain and ITS sequences, indicating that all of them (five strains) may belong to the same species. These five strains were closely related to Torulaspora globosa, but showed more than 3–7% sequence divergence from T. globosa and all other species in the genus Torulaspora in the combined sequence analysis of D1/D2 domain and ITS region of rRNA gene. In addition, these strains also showed distinct microsatellite finger-printing pattern from related species and differed in several physiological responses suggesting that these strains belong to a novel species of Torulaspora. We propose to name these strains as Torulaspora indica sp. nov., and designate APSS 805T = MTCC 9772 T = CBS 12408 T as the type strain of this novel species. The Mycobank number of the novel species is MB 563738.  相似文献   

14.
 Paste viscosity parameters play an important role in estimating the eating, cooking and processing quality of rice. Four cytoplasmic male-sterile (CMS) lines and eight restorer (R) lines were employed in an incomplete diallel cross to analyze seed effects, cytoplasmic effects and maternal gene effects on the viscosity profiles of indica rice. The results indicated that the viscosity profiles of rice were controlled by the direct effects of the seed, by the cytoplasm and by maternal plant. The seed-direct effects (V A +V D ) accounted for over 51% of the total genetic variances (V A +V D +V C +V Am +V Dm ) for all the traits, suggesting that seed direct effects were more important than maternal effects and cytoplasmic effects. The additive variances (V A +V Am ) were much larger than the dominance variances (V D +V Dm ), which revealed that additive genetic effects were the major contributors of genetic variation for the paste viscosity profiles, and that selection could be applied for viscosity traits in the early generations. Significant cytoplasmic variance (V C ) was detected for hot paste viscosity (HPV), cool paste viscosity (CPV) and consistency viscosity (CSV). The cytoplasmic effects for these three traits can, therefore, not be neglected in rice breeding. It was also shown that seed heritabilities (h 2 o ) tended to be larger than maternal heritabilities (h 2 m ) and cytoplasmic heritabilities (h 2 c ). Prediction of the main genetic effects for 12 parents showed that CMS lines had highly positive effects on all the traits except for the breakdown viscosity (BDV), and that R lines had both positive and negative effects on the paste viscosity characteristics. Received: 3 August 1998 / Accepted: 28 November 1998  相似文献   

15.
The structure of the mature stomatal complex of Flagellaria indica L. was studied since the Flagellariaceae is reported to be one of a handful of nongrass families with a grass-type stoma, and since relatively little is known about stomatal ultrastructure in monocots other than grasses. Both the grass guard cell and its nucleus are dumbbell-shaped, and the walls that separate adjacent grass guard cells are perforated. Electron and fluorescence microscopy reveal that the Flagellaria guard cell lacks these features. Instead, the Flagellaria guard cell is neither dumbbellnor kidney-shaped, its nucleus is roughly kidney-shaped, and the end walls are thickened and imperforate. Additional structural features of the stomatal apparatus of Flagellaria include: 1) the subsidiary cells have a protuberance that underlies the middle of the guard cell and that forms an additional and innermost aperture of the pore; 2) guard and subsidiary cell walls are thickened differentially and are layered; and 3) organelles in both cell types appear to be confined to specific domains. Although Flagellaria is closely related to grasses, it does not have a grass or dumbbell-shaped type of stomate. This suggests that the grass type of stomate may be less widespread than reported.  相似文献   

16.
Summary Immature seeds of Garcinia indica Choiss, were exeised from immature fruits and cultured on Lloyd and McCown (1980), woody plant medium (WPM) with different combinations of auxins and cytokinins. Somatic embryos were obtained on the media supplemented with 6-benzy laminopurine (BA; 2.2–22.1 μM) alone or in combination with α-naphthalene acetic acid (NAA; 2.6 μM) with 80% frequency within a period of 2–3 wk. Subculture of embryos on medium containing BA (16.0 μM) supplemented with indole-3-acetic acid (IAA: 2.8–5.7 μM) and/or kinetin (4.6 μM) gave rise to clusters of secondary somatic embryos along with maturation of primary embryos. In subsequent subculture on hormone-free half-strength WPM, the embryo clusters germinated with an increase in the number of secondary somatic embryos. About 70% of somatic embryos germinated into complete plantlets, which were successfully established under greenhouse conditions.  相似文献   

17.
A modified culture protocol has been developed for the induction of somatic embryogenesis in Azadirachta indica (neem). Embryogenic calluses were initiated from cotyledons or hypocotyls using a Murashige and Skoog (MS) agar medium supplemented with 0.5 mg l−1 α-napthaleneacetic acid (NAA), 1 mg l−1 6-benzylaminopurine (BA), 1 g l−1 casein hydrolysate, and 50 g l−1 sucrose. The calluses, when transferred to a liquid medium similar to the agar medium but with NAA replaced by 0.5 mg l−1 indole-3-acetic acid (IAA), formed globular structures which further developed a rudimentary root, after 4 to 5 weeks incubation. Subsequently, these highly differentiated tissues when transferred into a hormone-free MS medium containing 1 g l−1 casein hydrolysate and 50 g l−1 sucrose, active embryo masses started to appear after 1 to 2 weeks. The embryo production was found to improve more than 2 fold by adding 0.2 mg l−1 zeatin to the medium. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

18.
A rapid and efficient in vitro plant regeneration method was developed for Aristolochia indica. Multiple shoot formation was induced from shoot tip and nodal explants on Murashige and Skoog (MS) medium with 1 – 6 mg dm−3 2-isopentenyl-adenine (2-iP) or 1 – 4 mg dm−3 6-benzyladenine (BA). Maximum number of shoots were induced with 5 mg dm−3 2-iP alone (about 12 – 14 shoots). Shoot differentiation occurred directly from the leaf bases as well as from the internodes when cultured on 1 – 4 mg dm−3 BA and 0.8 – 2 mg dm−3 α-naphthaleneacetic acid (NAA) containing medium. Regeneration from the callus occurred when the calli initiated on MS medium containing 0.6 – 4 mg dm−3 NAA in combination with 0.8 – 3 mg dm−3 BA were transferred to 1 – 6 mg dm−3 BA alone containing medium. Elongated shoots were separated and rooted in MS medium containing 1 mg dm−3 indole-3-butyric acid. These were then transferred to soil after gradual acclimatization.  相似文献   

19.
Abstract

Mango, Mangifera indica L. Family – Anacardiaceae, an economically important fruit tree, was selected to study the effect of seasonal changes of the population of plant parasitic nematodes viz., Hoplolaimus indicus, Helicotylenchus indicus, Rotylenchulus reniformis, Tylenchorhynchus mashoodi, Tylenchus filiformis and Hemicriconemoides mangiferae around the roots. The population was investigated at 10, 20 and 40 cm depths. It was observed that seasonal fluctuations have a direct effect on the nematode population. The population was larger at 10 cm depth followed by 20 and 40 cm depths. The largest nematode population was observed when the percent soil moisture was high. Both soil temperature and soil moisture were equally important. The soil pH also affected indirectly the nematode population densities.  相似文献   

20.
Hybrid sterility between indica and japonica subspecies in rice is basically caused by partial abortion of gametes and hybrid fertility could be recovered by a single wide compatibility (WC) allele. In this study, a typical indica germplasm source of rice, UPRI 95-162, with strong wide compatibility in cross with japonica rice was studied for location of its WC locus. Bulked segregant analysis was performed and SSRs (simple sequence repeats) were conducted on a F1 population derived from a three-way cross (UPRI 95-162/T8//Akihikari). The locus was located on chromosome 1 approximately 0.2 cM to SSR markers RM581 on one side and 1.5 cM to RM292 on another. This WC locus, tentatively designated as S-20 n (t), and its tight linkage markers, RM581 and RM292, would be very useful for efficient marker-assisted selection for breeding new WC varieties and for map-based cloning of the gene.  相似文献   

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