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1.
Fruit characteristics of the disease-resistant bluggoe-type (ABB) cooking bananas (Musa × paradisiaca L.) ‘Saba’ and ‘Pelipita’ were compared with those of the susceptible ‘Currare’ (‘Horn’). Yields of ‘Saba’ and ‘Pelipita’ were similar to those of ‘Currare’; however, ‘Saba’ and ‘Pelipita’ yielded fewer hands with a greater number of small fruit when compared with ‘Currare’. Shoot-tip cultures of both clones were readily initiated on a modified Murashige and Skoog (MS) basal medium supplemented with N6-benzyladenine (BA) in combination with indole-3-acetic acid (IAA). Propagation cultures were initiated by splitting shoot tips along their longitudinal axis and re-culturing the individual pieces to basal medium supplemented with 5 mg l?1 BA. Transfer of axillary shoots to hormone-free medium resulted in rapid and extensive root formation. Plantlet survival after transfer to methyl bromide-treated soil exceeded 90%. Establishment in the field was achieved following procedures normally used for vegetative propagation of this crop. Trial plantings of in vitro propagated ‘Saba’ and ‘Pelipita’ were established in various provinces of Costa Rica for grower evaluation and for future comparison of growth and reproductive development with plants of these and other cultivars propagated from corms.  相似文献   
2.
Summary Nineteen single-copy clones isolated from a PstI genomic library (cv. Maiden Plantain), and eight Vigna chloroplast DNA clones were used to probe total genomic DNA digests of 57 genotypes of Musa from India. The 19 genomic clones detected a total of 107 polymorphisms among the 57 genotypes. Principal coordinates and phenetic analyses of these data placed cultivars and species into distinct groups that were in general agreement with a previously published RAPD-based classification of these same plant materials. The 107 polymorphisms were sufficient to differentiate each clone from every other clone. Heterologous Vigna chloroplast DNA probes were used to characterize the cytoplasm of Musa cultivars and species. PCO analysis of these RFLPs were detected both within and between the generally recognized genome groups, indicating multiple hybridization pathways in the origin of hybrid clones. Data presented demonstrate that RFLPs are sufficiently abundant to classify Musa germplasm and that genetic relationships among Musa cultivars, based upon RFLP data, are in general agreement with relationships determined by analysis of morphology and RAPDs.  相似文献   
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4.
Approximately 1100 genebank accessions of okra (Abelmoschus esculentus) and 540 additional accessions that included six of its related species-A. caillei, A. crinitis, A. esculentus, A. ficulneus, A. manihot, A. moschatus and A. tuberculatus-were evaluated for seed oil content using time domain NMR (TD-NMR). Oil content in seed of A. caillei, A. esculentus, A. ficulneus, A. manihot, A. moschatus and A. tuberculatus was in the ranges 2.51-13.61%, 12.36-21.56%, 6.62-16.7%, 16.1-22.0%, 10.3-19.8% and 10.8-23.2%, respectively. Accession PI639680 (A. tuberculatus) had the highest seed oil content (~23%). Accessions of A. esculentus with high seed oil content included PI nos. PI274350 (21.5%), PI538082 (20.9%) and PI538097 (20.9%). Values for the three accessions of A. manihot with the highest seed oil content were PI nos. PI639673 (20.4%), PI639674 (20.9%) and PI639675 (21.9%), all representing var. tetraphyllus. Average percent seed oil in materials of A. esculentus from Turkey and Sudan (17.35% and 17.36%, respectively) exceeded the averages of materials from other locations. Ninety-eight accessions (total of six species) were also examined for fatty acid composition. Values of linoleic acid ranged from 23.6-50.65% in A. esculentus. However, mean linoleic acid concentrations were highest in A. tuberculatus and A. ficulneus. Concentrations of palmitic acid were significantly higher in A. esculentus (range of 10.3-36.35%) when compared to that of other species, and reached a maximum in PI489800 Concentrations of palmitic acid were also high in A. caillei (mean = ~30%). Levels of oleic acid were highest in A. manihot, A. manihot var. tetraphyllus and A. moschatus.  相似文献   
5.
The United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Plant Genetic Resources Conservation Unit in Griffin, GA maintains the United States germplasm collection for Ipomoea spp. (Convolvulaceae). During 2012–2014, 737 sweetpotato, Ipomoea batatas (L.) Lam., plant introductions (PI) were acquired as tissue-culture plantlets and then acclimated to greenhouse conditions at the USDA, ARS, U. S. Vegetable Laboratory (USVL), Charleston, SC. Single plants were transferred to plastic-covered plant beds to produce cuttings for replicated field trials. Storage roots were harvested from 690 PIs grown in the field and 695 PIs grown in pots. Color coordinates were obtained for each PI using a tristimulus colorimeter. Hue angle values (h*) ranged from 8.2° to 88.3° (\( \bar{x} \) = 54.9°) for the periderm (peel or skin) of field-grown storage roots (n = 690 PIs) and ? 9.4° (= 350.6°) to 96.2° (\( \bar{x} \) = 51.3°) for pot-grown roots (n = 695 PIs). The red–green coordinate (a*) ranged from 0.8 to 30.7 (\( \bar{x} \) = 12.8) for the periderm of field-grown roots and ? 2.0 to 44.9 (\( \bar{x} \) = 16.1) for pot-grown roots. The yellow–blue coordinate (b*) ranged from 2.8 to 33.1 (\( \bar{x} \) = 19.4) for the periderm of field-grown roots and ? 7.4 to 38.1 (\( \bar{x} \) = 19.3) for pot-grown roots. Color saturation (chroma, C*) ranged from 13.7 to 35.8 (\( \bar{x} \) = 24.9) for the periderm of field-grown roots and 14.9–45.5 (\( \bar{x} \) = 29.3) for pot-grown roots. Lightness (white–black, L*) ranged from 32.6 to 81.7 (\( \bar{x} \) = 54.6) for the periderm of field-grown roots and 32.1–88.2 (\( \bar{x} \) = 64.0) for pot-grown roots. Hue angles ranged from ? 13.1° (= 346.9°) to 100.9° (\( \bar{x} \) = 80.9°) for the stele (flesh) of field-grown storage roots (n = 672 PIs) and ? 29.9° to 103.5° (\( \bar{x} \) = 81.6°) for pot-grown roots (n = 676 PIs); a* ranged from ? 5.6 to 35.0 (\( \bar{x} \) = 8.0) for the stele of field-grown roots and ? 6.0 to 41.0 (\( \bar{x} \) = 7.6) for pot-grown roots; and b* ranged from ? 7.7 to 56.1 (\( \bar{x} \) = 34.6) for the stele of field-grown roots and ? 12.6 to 56.1 (\( \bar{x} \) = 31.8) for pot-grown roots. C* ranged from 12.7 to 65.8 (\( \bar{x} \) = 37.2) for the stele of field-grown roots and 8.9–65.7 (\( \bar{x} \) = 34.5) for pot-grown roots; and L* ranged from 27.8 to 91.1 (\( \bar{x} \) = 77.7) for the stele of field-grown roots and 28.2–91.9 (\( \bar{x} \) = 80.4) for pot-grown roots. There were significant relationships between stele color (h*) and percent dry matter, with orange stele having a significantly lower % dry matter (\( \bar{x} \) = 25.6%, n = 183) compared with roots with cream/white stele (\( \bar{x} \) = 30.8%, n = 373). There appears to be wide genetic diversity for root color characteristics for the United States sweetpotato germplasm collection.  相似文献   
6.
Uapaca kirkiana (Muell. Arg.), a highly valued indigenous fruit species, is being domesticated to increase its utilization in southern Africa. Vendors, who were also the fruit gatherers, that were selling U. kirkiana fruits at roadside markets in Dedza, Malawi, were interviewed on four occasions during the marketing season (October 2003–January 2004) and fruit samples were concurrently sampled from each vendor. Information was obtained on when and how the fruits had been harvested and handled. Timing of fruit harvest was based on experience, aided by indicators such as occurrence of first heavy rains, natural abscission, size and color changes. Harvesting by knocking down unripe fruits from trees was practiced throughout the␣season, but naturally abscised fruits were also gathered in December and January. Fruits harvested when mature but unripe required incubation in soil, plain and woven plastic bags or clay-pots. The incubation method changed and the duration of incubation decreased between October (3–4 days) and January (≤2 days). Fruit samples were evaluated for damage, color and soluble solids concentration (SSC). Fruit SSC and color lightness/brightness (L*) increased from 10.1 to 16.4% (P<0.01) and from 45.7 to 50.5 units, (P<0.01), respectively. Higher SSC values were generally associated (R 2=0.68, P<0.001) with increasing pulp color intensity. Cracking, at 48%, constituted the most common form of damage in sampled fruits. On average, fruits were saleable for only 3–4 days, this being attributed to inherent fruit characteristics combined with immaturity at harvest, and damage during harvesting and storage in hot dry conditions. Lack of appropriate harvesting and handling techniques were associated with fruit darkening, drying, rotting and other postharvest problems.  相似文献   
7.
The internal transcribed spacer regions (ITS1 and ITS2) of the 18S-25S nuclear ribosomal DNA from the four recognized species of Citrullus (C. lanatus var. lanatus (Thunb.) Matsum. & Nakai., C. lanatus var. citroides (Bailey) Mansf., C. colocynthis (L.) Schrad., C. ecirrhosus Cogn., and C. rehmii De Winter) and Acanthosicycos naudinianus (Sond.) C. Jeffrey were amplified by PCR, and direct sequenced. Within the taxa examined, the length of ITS1 varied from 216 bp to 219 bp, and ITS2 varied from 239 bp to 249 bp. The average %CG content ranged from 59 to 64% and from 62 to 66% for ITS1 and ITS2, respectively. The greater length variation observed in ITS2 was primarily attributable to the occurrence of a (CC)n microsatellite. Cladistic (PAUP) and phenetic (MEGA) analyses resulted in highly resolutive trees. ITS sequence analysis placed the recently described C. rehmii adjacent to the cultivated watermelon and supported the validity of the species classification of this taxa.  相似文献   
8.
Summary Fifty-seven accessions ofMusa including cultivated clones of 6 genomic groups (AA, AB, AAA, AAB, ABB, ABBB),M. balbisiana Colla (BB),M. acuminata Colla ssp.banksii F. Muell. (AA),M. acuminata Colla ssp.malaccensis Ridl. (AA) andM. velutina Wendl. & Drude were examined for random amplified polymorphic DNA (RAPD) genetic markers using PCR with sixty 10-mer random primers. Forty-nine of 60 tested primers gave reproducible DNA amplification patterns. The number of bands resolved per amplification was primer dependent and varied from 1 to a maximum of 24. The size range of the amplification products also differed with the selected primer sequence/genotype and ranged from 0.29 to 3.0 kb. RAPD data were used to generate Jaccard's similarity coefficients which were analyzed phenetically. Phenetic analysis separated clones into distinct groupings that were in agreement with clusterings revealed when data were subsequently analyzed by principal coordinate analysis (PCO). In both the phenetic and the PCO analyses, previously unclassified cultivars grouped with cultivars previously classified for their genomic group based on morphological keys. The implications of RAPD analysis forMusa germplasm classification, clonal identification, and management are discussed.  相似文献   
9.
Intact seed of 475 genebank accessions of Citrullus ( C. lanatus var. lanatus and C. lanatus var. citroides) were analyzed for percent oil content using TD-NMR. Extracts from whole seed of 96 accessions of C. lanatus (30 var. citroides, 33 var. lanatus, and 33 egusi), C. colocynthis (n = 3), C. ecirrhosus (n = 1), C. rehmii (n = 1), and Benincasa fistulosa (n = 3) were also analyzed for their fatty acids content. Among the materials analyzed, seed oil content varied from 14.8 to 43.5%. Mean seed oil content in egusi types of C. lanatus was significantly higher (mean = 35.6%) than that of either var. lanatus (mean = 23.2%) or var. citroides (mean = 22.6%). Egusi types of C. lanatus had a significantly lower hull/kernel ratio when compared to other C. lanatus var. lanatus or C. lanatus var. citroides. The principal fatty acid in all C. lanatus materials examined was linoleic acid (43.6-73%). High levels of linoleic acid were also present in the materials of C. colocynthis (71%), C. ecirrhosus (62.7%), C. rehmii (75.8%), and B. fistulosa (73.2%), which were included for comparative purposes. Most all samples contained traces (<0.5%) of arachidonic acid. The data presented provide novel information on the range in oil content and variability in the concentrations of individual fatty acids present in a diverse array of C. lanatus, and its related species, germplasm.  相似文献   
10.
Precision Agriculture - Potato (Solanum tuberosum) stem density variation in the field can be used to inform harvest timing to improve tuber size distribution. Current methods for quantifying stem...  相似文献   
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