Universidad Nacional de Mar del Plata. Argentina, Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET). Argentina.
DOI: https://doi.org/10.37855/jah.2008.v10i02.19
Key words: Cut-lettuce, heat shock treatments, ascorbic acid, total microbial counts, sensory attributes
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Abstract: Changes in ascorbic acid contents, microbial population and sensory attributes of cut Romaine lettuce subjected to thermal shocks were investigated. Immersion of cut lettuce in the thermal baths produced reduction in the ascorbic acid contents between 190 and 300 g kg-1, with the greater losses corresponding to the higher bath temperatures. However, the rate of ascorbic acid degradation during refrigerated storage was independent of the thermal treatment and all samples presented a sharp decrease during the first day of storage and a gradual decrease thereafter. Thermal shocks did not reduce the initial microbial population. During storage, an increment in microbial counts was observed, being more notorious in samples that had been exposed to the highest shock temperature (50 ?C). The thermal treatment at 50 ?C was the only one to delay the onset of midrib and edge browning up to four days of refrigerated storage. This midrib and edge browning was considered to the most relevant to the overall visual quality of the product.
Scuola Superiore S. Anna di Studi Universitari e di Perfezionamento, Piazza Martiri della Liberta 33, 56100 Pisa, Italia.
DOI: https://doi.org/10.37855/jah.2008.v10i02.20
Key words: Chemical thinning, flower bud differentiation, gibberellins, meristematic apex morphology, nectarine
Abstract: The aim of the research was to study the morphological and histochemical evolution of the bud meristems of 'Lavinia' nectarine cultivar. Moreover, the effectiveness of Release LC (a gibberellin chemical compound) in controlling the rate of flower bud differentiation was also evaluated. During a two-year period, the Release LC was applied in postharvest to avoid problems of possible chemical residues on marketable fruits. To determine the effect of treatment, several biological parameters such as initial flower and vegetative bud number, flower bud drop, evolution of the flower bud phenological stages, rate of bloom and fruit set were recorded. To establish the floral differentiation stage, the meristematic apices were collected before and after treatment and microscopically observed. The thin sections were analysed using histological (apex size, developmental stages of meristematic apex, co-axial stage), and histochemical (RNA fluorescent staining) techniques. In 'Lavinia' cv., the critical phase of the meristematic apex evolution occurred from May to June (60 and 90 days after full bloom): the presence of triple apices increased rapidly, the co-axial phase was achieved, the width and height of the meristematic dome increased markedly and the RNA appeared by a weak staining. As regards the flower bud differentiation control by exogenous treatments with Release LC, the different results obtained in our experiments indicate that the efficacy of treatment strictly depends on the growth stage of a meristematic apex.
College of Agriculture, Ibaraki University, Ami, Ibaraki, 300-0393, Japan, Graduate School of Agricultural and Life Sciences, Bunkyo-ku, Tokyo, 113-8657, Japan.
DOI: https://doi.org/10.37855/jah.2008.v10i01.03
Key words: Cucumber, gynoecious cultivar, fruit growth, fruit abortion, pollination, relative growth rate
Abstract: Fruit growth of the gynoecious cucumber 'NK x AN8' was measured non-destructively to clarify whether the presence of fruit at lower nodes caused the abortion of fruit at upper nodes. When only one fruit per plant was allowed to grow, fruit growth could be divided into two phases: slow exponential and fast exponential. Phase change from slow to fast occurred when cumulative temperatures (CTs) after anthesis reached 38 and 54?C d for pollinated and parthenocarpic fruit, respectively. The CT was calculated as the sum of the differences between daily temperatures and 5?C. When fruit at nodes 4 and above were allowed to grow, the first growth phase was prolonged. Furthermore, parthenocarpic fruit aborted frequently when the sum of the relative growth rate (RGR) with respect to the CT (the sum of RGRs) for fruit at lower nodes exceeded 0.1 g g-1 (?C d)-1. Pollination with pollen of the monoecious cucumber '028' strongly suppressed fruit abortion; a large number of fruits could develop to a commercial size even when the sum of RGRs for fruit at lower nodes exceeded 0.1 g g-1 (?C d)-1. These results suggested that fruit abortion is more related to the existence of actively growing fruit than to the absolute amount of dry mass accumulation in the fruit.
Central Institute of Medicinal and Aromatic Plants, Resource Centre, Allalasandra, Bangalore 560 065, India.
DOI: https://doi.org/10.37855/jah.2008.v10i01.04
Key words: Catharanthus roseus, ornamental plant, medicinal plant, corolla colour, inheritance
Abstract: In periwinkle (Catharanthus roseus), pink, white and red-eyed (white corolla with red centre) are three common corolla colours, which are due to epistatic interaction between two genes R and W. Violet corolla, which is not found commonly in natural populations, is reported to be due to another gene B which blues the pigment in pink genotypes (R- W-). Recently, another gene O and its allele Om have been reported to determine two uncommon corolla colours, orange-red and magenta corolla, respectively. Since, the relationship between genes determining violet, orange-red and magenta corolla was not known, a strain possessing violet corolla and white eye (VI) was crossed with strains possessing orange-red corolla and white eye (OR) and magenta corolla and white eye (MJ-1) to study: (i) the relationship between genes involved in the production of violet, orange-red and magenta corolla, (ii) to study the possibility of producing novel corolla colours and (iii) to determine the validity of the gene interaction models proposed earlier. The F1 plants of both crosses, VI x OR and VI x MJ-1, had violet corolla. The F2 generation of the cross VI x OR segregated into plants with (i) violet corolla, (ii) pink corolla, (iii) orange-red corolla, and (iv) white corolla in the ratio of 45:12:3:4, while the progeny of the backcross F1 x OR segregated into three types of plants, (i) violet corolla, (ii) pink corolla, and (iii) orange-red corolla in the ratio of 2:1:1. The F2 generation of the cross VI x MJ-1 segregated into five kinds of plants viz., (i) violet corolla, (ii) pink corolla, (iii) magenta corolla, (iv) rose corolla, and (v) white corolla in the ratio of 144:48:12:36:16, while the progeny of the backcross, F1 x MJ-1 segregated into four types of plants viz., (i) violet corolla, (ii) magenta corolla, (iii) rose corolla and (iv) pink corolla in the ratio of 1:1:1:1. The results suggested that genes involved B, R, W, O/Om and J were inherited independently and that the gene B blued the corolla pigment in B-RRwwO- genotypes but not in B-RRwwOm-jj and B-RRwwOm-JJ genotypes. No new corolla colours were observed in the studied crosses due to the interaction between genes governing violet, orange-red and magenta corolla. The observed segregation for different corolla colours in the studied crosses was same as that expected from independent segregation and known interactions between the genes involved, validating the earlier proposed models.
Department of Plant Molecular Biology and Biotechnology, Centre for Plant Molecular Biology, Tamil Nadu Agricultural University, Coimbatore-641 003, Tamil Nadu, India, Department of Biochemistry, Centre for Plant Molecular Biology, Tamil Nadu Agricultural
DOI: https://doi.org/10.37855/jah.2008.v10i01.05
Key words: Lycopersicon pimpinellifolium, Phytoene desaturase, RT-PCR, lycopene
Abstract: Tomato (L. esculentum Mill), a popular vegetable in tropics is an excellent source for vitamin A, C, carotenoids and other health related components. It tops the list of industrial crops because of its outstanding processing qualities. It is valued for both its fresh and processed forms. Biochemical analysis in different wild species, varieties and hybrids of tomato showed the wild species, Lycopersicon pimpinellifolium LA 1593 to be a rich source for lycopene specific genes. Partial cDNA of lycopene specific Phytoene desaturase gene TNAU P was isolated from L. pimpinellifolium LA 1593 by RT-PCR technique. Sequence analysis of the partial cDNA showed 99.6% similarity with already available Phytoene desaturase gene from L. esculentum. Also, the sequence showed considerable homology with Phytoene dehydrogenase, Zeta carotene desaturase and Phytoene desaturase genes from Gentian, Oryza, Momardica, citrus and pea. The high intensity of the amplified product in L. pimpinellifolium coupled with 99.6 % homology to L. esculentum inferred that the level of expression of Phytoene desaturase is more in L. pimpinellifolium. Isolation of Phytoene desaturase genes can be further exploited to produce transgenic plants with increased content of lycopene by transferring the genes from wild species to cultivars.
Graduate School of Agricultural Sciences, Tohoku University, Sendai 981-8555, Japan. Present address: GraduateSchool of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto 606-8522, Japan.
DOI: https://doi.org/10.37855/jah.2008.v10i01.01
Key words: ACC oxidase gene (DC-ACO1), Dianthus caryophyllus, ethylene biosynthesis, flower senescence, potted carnation
Abstract: 'Lillipot' carnation, which is usually cultivated as a potted ornamental, was transformed with a cDNA for carnation 1-aminocyclopropane-1-carboxylate (ACC) oxidase. Two lines, which harbor an sACO transgene, had a vase life of cut flowers more than twice longer than that of the non-transformed (NT) control. Flowers of the long vase life lines senesced with discoloring and browning in petal margins, which is typical to ethylene-independent senescence in carnation flowers. They produced negligible amount of ethylene for the first 8 day, whereas flowers of the NT control showed a climacteric ethylene production with a maximum on day 3. Transcripts for DC-ACS1 and DC-ACO1 were absent in petals of the long vase life flowers undergoing senescence. The present study revealed that transformation with sACO transgene may be useful to generate potted carnation plants with a long display time.
Faculty of Horticulture, Chiba University, Matsudo, Chiba 271-8510, Japan.
DOI: https://doi.org/10.37855/jah.2008.v10i01.06
Key words: perforatum L., artificial light, controlled environment, hyperforin, hypericin, long-day plant, St. John's wort
Abstract: Hypericin and pseudohypericin are the major bioactive constituents of floral parts of Hypericum perforatum L., mainly used for the treatment of neurological disorders and depression. The principle objective of the current study was to evaluate the effect of blue, blue and red mixed, and red light on flowering time and concentration of hypericin, pseudohypericin and hyperforin in the floral tissues of H. perforatum plants. The results revealed that red light promoted flowering and production of the three major medicinal components, indicating the influence of spectral characteristics of light on flowering of H. perforatum plants. Spectral quality of light was found to be an important factor in controlling the flowering of H. perforatum plants.
Department of Horticulture, Clemson University, Clemson, SC 29634-0375 USA; Coastal Research and Education Center, Charleston, SC 29414-5332 USA; Department of Packaging Sciences, Clemson University. Clemson, USA; Department of Plant Pathology and Physiol
DOI: https://doi.org/10.37855/jah.2008.v10i01.07
Key words: Asteraceae, feverfew, Tanacetum parthenium, time of harvest, water stress, parthenolide, phenolics
Abstract: Feverfew (Tanacetum parthenium [L.] Schultz-Bip., Asteraceae) products have shown high variability in the market. The objective of this study was to determine whether environmental factors affect the composition of key phytochemicals in feverfew. Plants of feverfew were exposed to water stress in greenhouse and commercial field conditions. The highest yield of parthenolide (PRT) was found in plants that received reduced-water regimes. Phenolics concentration was higher in plants grown under adequate-water conditions. The effect of time of harvest on PRT concentration and phenolics content was also investigated. Increased PRT was found during afternoon hours whereas total phenolic compounds decreased during the photoperiod and increased at night. When plants were exposed to artificial light during night hours, the phenolics content remained low. Our results revealed that manipulating the environment to favour increased accumulation of PRT resulted in a decline of phenolics content in feverfew. These findings have implications on standardization of herbal products.
Department of Agriculture, University of Arkansas at Pine Bluff, Pine Bluff, AR 71601, USA.
DOI: https://doi.org/10.37855/jah.2008.v10i01.08
Key words: Vigna unguiculata, shoot meristem, regeneration, transformation, legumes
Abstract: Cowpea is a highly recalcitrant nutrient-rich leguminous vegetable crop. Efforts to genetically transform cowpea with insect-resistant genes remains a challenging task due to lack of an efficient regeneration system. We have established an efficient regeneration system in cowpea through shoot meristem. Shoot meristems were isolated from embryos that were precultured for 3-5 days on Murashige and Skoog (MS) medium containing 8.9 uM benzylaminopurine (BA). The isolated shoot meristems were cultured on MS medium containing 0.89 uM BA. After 3-4 weeks, multiple shoots were separated from the explant and cultured on half-strength MS medium for elongation and rooting. More than 90% of the regenerants formed roots. The rooted plantlets were transferred first to peat pellets and subsequently to the greenhouse. The plants were allowed to flower and set seed. The efficiency of regeneration in all four cultivars ranged from 76-87%, demonstrating a significant improvement over the published protocols (1-32%). At least six to seven plantlets were obtained from each meristem. The protocol using shoot meristems is simple, efficient, rapid and genotype-independent and may be amenable for transformation through particle bombardment.
Plant Tissue Culture Division, CSIR National Chemical Laboratory, Pune - 411 008, India
DOI: https://doi.org/10.37855/jah.2008.v10i01.09
Key words: Crimson Seedless, grapevine, micropropagation, Vitis.
Abstract: Grapevine genotypes differ in tissue culture requirements and thus require optimized culture conditions for in vitro propagation. Single node segments of Crimson Seedless cultured on six different basal media i.e. Murashige and Skoog (MS), Eriksson (ER), Gamborg (B5), Nitsch and Nitsch (NN), Woody plant medium (WPM) and Chee and Pool (C2d) showed different percentage of shoot initiation and morphogenetic responses. The maximum shoot initiation (90.0%) was observed in MS medium. Except ER, all other media induced rooting at the base of nodal segments in varying percentages though number and quality of roots and their establishment on transfer to pots varied greatly. WPM induced the maximum rooting in nodal segments (69.1%) with establishment rate of 100.0%. Induction of multiple shoots in nodal segments was achieved on inclusion of 6-benzyl adenine (BA) (8.87 uM) and indole-3-butyric acid (IBA) (1.48 uM) in the MS medium. In second sub-culture i.e., at 90 days, shoot bud proliferation could be increased many fold on transfer of these initial shoot clumps to glass bottles instead of culture tubes. The maximum average number of primary shoots (19.5 per explant) was achieved on MS with BA (8.87 uM) and IBA (1.48 uM). Elongation of shoots was achieved on MS with BA (2.22 uM) + a-naphthalene acetic acid (NAA) (0.54 uM). Induction of ex vitro rooting and establishment of rooted shoots after transfer to pots was achieved in different efficiencies when shoots were given pulse treatment of indole-3-acetic acid (IAA) or IBA or NAA at 57.08, 49.0 and 53.71 uM, respectively, for 5 or 10 min. Survival of in vitro and ex vitro-rooted shoots on potting was 90.0 and 100.0%, respectively.
Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India.
DOI: https://doi.org/10.37855/jah.2008.v10i01.10
Key words: Spearmint, Mentha spicata, Zn-efficient genotype MSS-5, protein, photosyntheis, photosynthetic pigments, Zn toxicity.
Abstract: Changes in growth attributes, photosynthesis (Pn), photosynthetic pigments with y-Glu.cys peptidase peptide and Zn accumulation in a Zn-efficient genotype of spearmint MSS-5 were investigated. Effect of phosphorus toxicity on MSS-5 were significantly different than the other genotypes; Arka, Neera and control (the local strain), in terems of phenotypic changes in height and a decrease in chlorophyll contents and CO2 exchange rate. Heavy P manuring lead to the tolerance of Zn accumulation in MSS-5 with y-Glu.cys. peptidase peptide with high protein contents and Pn. Hence, the P toxicity induced a differential utilization of y-Glu.cys.peptidase peptide for higher accumulation of Zn in MSS-5 spearmint with higher photosynthetic rate for increasing the height and essential monoterpene oil(s). The study also indicated that accumulation of toxic heavy metal-Zn with y-Glu.cys.peptidase peptide made protein synthesis easier with antioxidants Zn cofactor enzymes.
University of Illinois Extension, Mt. Vernon, Illinois
DOI: https://doi.org/10.37855/jah.2008.v10i01.11
Key words: Biosolids, sewage sludge, Callicarpa, Ilex, pH, electrical-conductivity, nitrate.
Abstract: Growth of Callicarpa dichotoma (Lour.) 'Early Amethyst' and Ilex glabra (L.) 'Compacta' liners were evaluated in substrate containing 20, 40, 60, 80 and 100% composted biosolids as compared to a 3:2:1 (v:v:v) pine bark:peat:sand horticultural mix. Biosolid waste substrate amended with biosolids had higher pH, EC, nitrate, bulk density and container capacity compared to a standard horticultural nursery mix. Total porosity and air-filled capacity were greater for the control compared to substrate amended with biosolids. The effects of substrate amended with composted biosolids on growth varied for each species. Callicarpa dichotoma "Early Amethyst' liners grown in substrate amended with 20, 40 and 60% biosolid waste had greater shoot and root dry weight and a better visual evaluation compared to the control. Ilex glabra 'Compacta' liners grown in the control (standard nursery mix) had greater shoot and root dry weight and a better visual evaluation compared to any biosolid amended substrate. It was concluded that substrate amended with biosolid waste can be utilized for the container production of plants, however, its usage may be species specific.
Department of Fertilization Technology, National Research Centre, Dokki, Egypt.
DOI: https://doi.org/10.37855/jah.2008.v10i01.12
Key words: Olive, Olea europaea L., leaf nutrients, seasonal variations.
Abstract: The study was conducted for two successive years at a private farm in El-Saf, Giza, Egypt on 19 years old trees of olive cultivars, Picual, Aggizi and Manzanillo, grown in calcareous soils. Leaf nutrients were measured bi-monthly during the 2001-2002 growing season. The study revealed that most of nutrients in the soil were at inadequate level. Nutrient concentrations in the leaves of the three cultivars were nearly the same. Results revealed that leaf N ranged between low to satisfactory. P contents were adequate in spring while inadequate in summer. K leaf contents were adequate. Peaks of Mg were found to be the highest during winter. Ca peaks were observed during March-June. Fe and Zn were inadequate while Mn was adequate. The concentrations of Fe, Mn and Zn peaked during June, which could be due the repeated foliar application of these nutrients during this period. The seasonal nutrient changes (N, P, K, Ca, Mg, Fe, Mn, Zn and Cu) of the olive leaves are supposed to be used as a guide for proper fertilization. Nutrients should be added as acidic fertilizer to the soil, which is useful in calcareous and high pH conditions.
North Mississippi Research and Extension Center, P.O. Box 1690, Verona, MS, 38879, USA.
DOI: https://doi.org/10.37855/jah.2008.v10i01.13
Key words: Zinnia elegans, zinnia, cut flower, field production
Abstract: The objective of the study was to evaluate the effects of cultivar and planting date on zinnia (Zinnia elegans) cut flower production. Parameters evaluated were the number of days to harvest, duration of harvest period for each planting date, number of stems per plant, stem length and diameter. Plants from the May planting date produced stems over a longer period of time compared to plants from the June and July plantings with the exception of 'Scarlet Splendor' from the July planting. Within each of the three planting dates, there were no statistically significant differences in the number of stems produced per plant due to the cultivar effect for 10 of the 13 cultivars evaluated. A trend of increasing stem and bloom size from the May planting date to the July planting was observed. The median number of stems produced by the zinnia cultivars in this study from the May, June, and July planting dates were respectively 21.6, 10.8 and 14.5 stems per plant for plants spaced one foot apart in the row. The potential stem yield for a single 100 ft row of the zinnia cultivars included in this trial was 2160, 1080 and 1450 stems for the production life of May, June, and July plantings, or 4690 stems for the three plantings combined. The cut flower zinnias evaluated in this study were very productive during the summer growing season.
National Bureau of Soil Survey and Land Use Planning, Amravati Road, Nagpur-440 010, Maharashtra, India.
DOI: https://doi.org/10.37855/jah.2008.v10i01.14
Key words: Grape, soil characterstics, growth, yield, drainage, depth, available water content
Abstract: Six grape growing typical pedons in Nasik district, Maharashtra were characterised and soil-site parameters were correlated with yield and yield attributes of the crop. These soils were very shallow (Darana), moderately deep (Mahiravani, Kothure), shallow (Shivdi), deep (Talegaon) and very deep (Andersool) and characterised by well drained (Darana, Mahiravani, Shivdi) and moderately well drained (Talegaon, Kothure, Andersool). The height, stem girth, spread volume, bunch per plant, berries per bunch were very much related with soil depth, drainage, pH, available water content and DTPA extractable micronutrient cations.