Involvement of ABA in postharvest life of miniature potted roses

Exogenous application of ABA (abscisic acid) to intact miniature potted rose plants (Rosa hybrida L.) resulted in deterioration of postharvest quality of two cultivars. Spraying with ABA increased leaf drop and accelerated flower senescence in Vanilla and Bronze, while bud drop was only induced in Bronze. Application of ABA to detached rose flowers accelerated their senescence, indicating that the observed senescence promoting effect was not a secondary response resulting from ABA-induced leaf senescence and abscission. ABA-treatment increased ethylene production in Bronze flowers, while no ethylene production was measured in flowers of Vanilla, or in the leaves of both cultivars. Pre-treatment with 1-MCP (1-methylcyclopropene) delayed ABA promoted flower senescence in Bronze, suggesting that the effect of ABA is at least partly mediated by ethylene. The senescence promoting effect of ABA on leaf drop and flower life of Vanilla flowers was not counteracted by 1-MCP pre-treatment. The cultivar Vanilla had a low ABA level at all flower stages, while ABA content of the Bronze petals was high in buds, lower in open flowers, and increased during flower senescence. An increased ABA content after ethylene treatment in Vanilla suggests that ethylene, natural or exogenous, can increase ABA levels of flowers.     

Involvement of abscisic acid in bulb dormancy of Allium wakegi Araki. II. A comparison between dormant and nondormant cultivars

The content of abscisic acid (ABA) in bulbs of two Allium wakegi Araki cultivars, Kiharabansei No. 1 (dormant type) and Ginoza (nondormant type), was similar and changed similarly during the development and storage of the bulbs. It increased during bulb development, reached a maximum shortly after bulb harvesting, and gradually decreased during bulb storage. The bulbs of Kiharabansei No. 1 showed dormancy correlated with the change in ABA content, but those of Ginoza did not show significant dormancy throughout the experimental period. The ABA content in the buds of dormant bulbs of Kiharabansei No. 1 did not change after planting of bulbs, but that of nondormant bulbs of Ginoza planted on the same day rapidly decreased after planting. Application of ABA to bulbs delayed sprouting of both cultivars, but dormant bulbs of Kiharabansei No. 1 had higher sensitivity to ABA than the bulbs of Ginoza or the bulbs of Kiharabansei No. 1 partly released from dormancy. These results suggest that the decrease in the ABA content after planting (watering) and low sensitivity to ABA are correlated with the nondormancy of Ginoza.     

Heritable variation in the phaseolin protein of nondomesticated common bean,Phaseolus vulgaris L.

Summary Crude protein extracts from single seeds of nondomesticated Mexican bean accessions were analysed by SDS polyacrylamide gel electrophoresis for variability in phaseolin protein. Six new phaseolin types; M1, M2, M3, M4, M5, M6, which contained polypeptides within the same range of molecular weights (51,000 to 45,000 daltons) as occur in the S, T and C phaseolin types of cultivated beans were identified. No T and C types were found among the non-domesticated Mexican accessions, and the S type occurred in less than 7% of the seeds screened. Genetic analyses of F₂ progenies from crosses between Sanilac (S), and five of the M types showed that each M phaseolin phenotype was allelic to the S type and expressed codominantly.     

Selection of isoresponsive genotypes in toria (Brassica campestris L.) based on the pattern of response to environmental variations: a proposed method

Summary Thirty-one toria genotypes were compared with three well-established cultivars, Ludhiana Composite-2, K-1 and TCSU-2 (standard testers). The genotypes, which were almost identical to a standard tester in response to environmental variations and which also had other desirable characteristics, were considered to be acceptable for commercial cultivation. Using this criterion, TCSU-7, TH-5 and TH-4 were found to be acceptable for commercial cultivation. TH-4 and TCSU-7 were found superior to TH-5 if r² can be considered as a measure of the agronomical manipulations expected in environmental variations.     

Genetic analysis of resistance to whitebacked planthopper in twenty-one varieties of rice,Oryza sativa L.

Summary The inheritance of resistance to whitebacked planthopper Sogatella furcifera (Horvath) was studied in 21 rice varieties. Reactions of F₁; F₂ and F₃ progenies of the crosses of 21 resistant varieties with the susceptible variety TN 1 revealed that a single dominant gene governs resistance in Mushkan 41, Santhi, Siahnakidar 195, SM2-34, Tirisurkh 251, Zirijowaian 245, 18, 24A, 39, 76 S, 78, 180, 213 B, 267, 293, CI 6037-4, NP97, S39 JKW and Bansphul. In varieties 65 and 274 A, resistance is governed by one dominant and one recessive gene which segregate independently of each other. Tests for allelism with the Wbph 1 gene originally identified in N 22 revealed that the dominant gene present in all the test varieties is the same as Wbph 1. Further studies are required to determine the allelic relationships of the recessive gene found in varieties 65 and 274 A.     

Endogenous abscisic acid and 2-trans-abscisic acid in alternate bearing ‘Wilking’ mandarin trees

The relationship of abscisic acid (ABA) and 2-trans-abscisic acid (t-ABA) to alternate bearing has been examined in Wilking mandarin (Citrus reticulata Blanco) trees. Leaves, stems and buds of trees loaded with fruit (on trees) had 4.3, 6.0 and 2.2 fold higher ABA levels than the corresponding organs from off trees. Leaves had higher ABA levels than stems and buds in both on and off trees. t-ABA was non-detectable in Wilking leaf, stem and bud tissue. Amounts of t-ABA not exceeding 40% of the ABA content, were found in Shamouti and Valencia orange buds and in Wilking fruit peel.The elevated levels of ABA in on tree organs may reflect a stress imposed by the fruit overload.     

Effect of Gamma Irradiation on Embryogenic Avocado Cultures and Somatic Embryo Development

Embryogenic avocado cultures were exposed to ionizing irradiation in order to determine its effect on proliferation and subsequent somatic embryo development. The approximate PD₅₀ as determined by linear regression is 35 Gy 2 weeks after irradiation for Fuerte 2.11.1 and 4 weeks after irradiation for T362 2.11.1. Irradiation of embryogenic cultures did not significantly affect the number of early stage Fuerte 2.11.1 somatic embryos that developed directly from irradiated cultures; however, 10–50 Gy inhibited somatic embryo development. Irradiation of T362 2.11.1 embryogenic cultures at 25–50 Gy inhibited the number of intermediate and mature stages of somatic embryos that developed directly from irradiated cultures, and 50 Gy inhibited somatic embryo maturation. Inhibition of somatic embryo development could be partially offset by proliferation of irradiated embryogenic cultures as suspensions. Irradiation up to 10 Gy significantly increased the number of mature Fuerte 2.11.1 somatic embryos that developed from suspension cultures. Irradiation with doses up to 25 Gy stimulated development of heart stage T362 2.11.1 somatic embryos; however, mature somatic embryo development was suppressed at dosages of 10 Gy and greater.     

Water stress-induced oxidative damage and antioxidant responses in micropropagated banana plantlets

Oxidative injury and antioxidant responses were investigated in two banana genotypes (Musa AAA Berangan and Musa AA Mas) subjected to 40 % PEG-induced water stress. PEG treatment resulted in oxidative injury, as expressed in increased lipid peroxidation and reduced membrane stability index, in both cultivars; however, greater oxidative injury was detected in Mas. Under PEG treatment, catalase activity and glutathione reductase activity were enhanced in both cultivars, but were higher in Mas. Ascorbate peroxidase activity was enhanced in Berangan under water stress, but was unaffected in Mas. Meanwhile, superoxide dismutase activity was inhibited in both cultivars under water stress, but higher activity was detected in Berangan. Higher ascorbate peroxidase and superoxide dismutase activities were associated with greater protection against water stress-induced oxidative injury.     

Monosomic analysis of heading date and spikelet number in the common wheat (Triticum aestivum L.) multispikelet line ‘Noa’

Summary Genetic analysis of heading date and spikelet number was carried out in the common wheat (Triticum aestivum L.) multispikelet line Noa, by using the monosomic series of the regular line Mara. Noa's high number of spikelets was found to be controlled by a recessive major gene on chromosome 2D; a slight reduction in spikelet number was induced by another recessive gene on Noa's 7A chromosome. Noa's late heading date was found to be controlled by two recessive genes, located on chromosome 2D (a major effect) and 6B (a minor effect). The nature of the genes located on Noa's 2D chromosome and the relationship between spikelet number and heading date are discussed.     

A simple method for maintaining high multiplication of Narcissus shoot cultures in vitro

A simple method for stimulating and maintaining high in vitro multiplication of Narcissus shoot clump cultures was developed. Shoot clumps were subjected either to normal cutting where leaves were trimmed to 20 mm in length at the beginning of each culture passage or to severe cutting where shoot clumps were cut down to the basal plate region removing all green tissue. Severe cutting at the beginning of each culture passage initially doubled the leaf multiplication, compared to normal cutting, but the difference between cutting treatments declined in successive passages. The improvement in leaf multiplication was maintained when shoot clumps were subjected to severe cutting only at every other culture passage, with no cutting in the alternate recovery passages. In vitro multiplication was increased by severe cutting in all seven Narcissus cultivars which were tested.Abbreviations NAA-1 naphthylacetic acid - BAP benzylaminopurine     

An explication of ‘wind illness’ in Northern Thailand

Wind illness is a very common complaint among the Northern Thai, yet is rarely recognized by Thai physicians trained in biomedicine. Persons most susceptible to wind illness are adult women who have ever borne a child. Consequently, data were obtained from 415 everparous women, 43% of whom reported ever having had wind illness and 57%, never having had it. In addition, 20 individuals who had ever had the syndrome were followed for case study, and 13 indigenous healers who traditionally treat clients suffering wind illness were interviewed. Their perceptions of the etiology, symptomatology and treatment of wind illness are reported in Part I. Part II is an attempt to define wind illness in terms of biomedicine and as a consequence of fertility. Part III synthesizes the emic and etic accounts with explanations for the perdurance of wind illness despite the advances of biomedicine and the recent fertility decline in Northern Thailand.     

Esterase isozymes in rye — characterization,genetic control and chromosomal location

Summary The zymogram phenotypes that Chinese Spring-Imperial, Holdfast-King II and Kharkov-Dakold wheat-rye addition lines presented for esterase isozymes were determined using polyacrylamide gel ectrophoresis. The analyses were carried out with different parts of the dry kernel, namely embryo plus scutellum and endosperm, leaves and roots. In all cases, embryo plus scutellum, endosperm and leaf presented different patterns of esterases. The patterns of leaves and roots were the same. Results indicate that rye esterases exist as monomers and dimers. Dimeric esterases are controlled by one locus located on the 3R chromosomes of Imperial, King II and Dakold rye cultivars. Five loci involved in the production of monomeric esterases have been located on the 6R chromosomes of these cultivars, specifically on the long arm of the King II 6R chromosome. On the basis of these results, considerations concerning chromosome homoeology and homology are made.     

Pitiriasis versicolor por malassezia ovalis

In a randomly collected series of 175 cases of pityriasis versicolor in residents of the central-northern part of Venezuela, 13% of the patients were infected with ovoid unicellular units of the causal fungus (Malassezia ovalis) and 87% with globous unicellular units in the scales (M. furfur). Only globous unicellular units (Pityrosporum orbiculare) were seen outside the active lesions and in these, after the successful treatment with ketoconazole. The median age of 40 ovalis patients was 37.5 years; the same in 40 furfur patients was 24.5 years. The median age at the moment of discovering the first lesions among ovalis patients was 31; among furfur patients this was 20 years. There were 16 male patients among the ovalis and 24 among the furfur groups of 40. The topographic distribution of the lesions varied according to the type of the invader. M. ovalis prevailed on the trunk below the waist-line and on the limbs, mainly on buttocks and upper legs. M. furfur prevailed on the chest, neck, face and upper limbs.The hypothesis is offered that the ovoid agent of pityriasis versicolor preferentially occupies the less sweating and sebum-producing parts of the body in older (and drier) persons than the globous type does.     

Thidiazuron substitution for chilling requirement in three apple cultivars

Thidiazuron [(TDZ)N-phenyl-N-1,2,3-thidiazol-5-ylurea] at 750 M was applied to buds of apple trees to determine if it could substitute for the chilling requirement to induce bud break. Shoots of cv. Anna (low chill), Delicious cv. Redchief (medium chill), and Northern Spy (high chill) were untreated, treated with TDZ prior to chilling (before-chill), and treated with TDZ at various intervals after the accumulation of specific amounts of chilling (after-chill). Shoots were stored in a cold room at 4°C. TDZ applied prior to chilling reduced the chill unit (CU) requirement (1 CU = 1 h at 4°C) for the promotion of bud break on 1-year-old shoots of Anna and Northern Spy and 1- and 2-year-old wood of Delicious. TDZ applied after-chill promoted bud break only for Anna and buds on 2-year-old wood of Delicious. While accumulating CUs, untreated buds or buds treated with TDZ on 1-year Delicious and Northern Spy did not respond to the cold treatment even after 1848 h of CU accumulation. For all three cultivars, TDZ treatment was more effective in promoting bud break when applied before the initiation of chilling.The use of a company or product name does not constitute an endorsement by USDA or the University of Maryland nor imply approval to the exclusion of other suitable products.     

Analysis of the organogenetic potential of calli of three Canary Island Lycopersicon esculentum land races

The organogenetic potential from callus of three tomato land races from the Canary Islands adapted to semi-arid environment (Salvaje, Rusa and Especial), and one tomato cultivar (Meltine), were examined. The response of four explant types (cotyledon, shoot apex, hypocotyl and root) to nine PGR regimes (BAP at 1 or 2 or 5 mg/l) + either IAA (0.5 mg/l) or 2,4-D (0.5 or 1 mg/l) were measured. BAP at 5 mg/l+IAA at 0.5 mg/l induced most organogenesis in all the explant types for all genotypes. Salvaje has one of the highest organogenetic potentials described in tomato.Abbreviation OP = organogenetic potential     

Study on the vesicular-arbuscular mycorrhiza of three cultivars of potato (Solanum tuberosum L.)

Summary The establishment and development of vesicular-arbuscular mycorrhizal (VAM) fungi were studied in three cultivars of potato, which differed in susceptibility to Late blight, in a field experiment on a lateritic sandy-loam during two growing seasons (1980 and 1981). The cultivars SSC 1174 (highly resistant) and Kufri Jyoti (resistant) showed an earlier establishment and more rapid development of VAM fungi than up-to-date (highly susceptible). The first mycorrhizal infection in both SSC 1174 and Kufri Jyoti was observed after 12 days in 1980 and 8 days in 1981, whereas in up-to-date it was observed after 19 and 12 days respectively. The mycorrhizal infection increased with the age of the plants in all the three cultivars.     

Demonstration of ‘cardiac-specific’ myosin heavy chain in masticatory muscles of human and rabbit

Summary Human and rabbit masticatory muscles were analyzed immuno-and enzyme-histochemically using antibodies specific to cardiac , slow and fast myosin heavy chain isoforms. In human masseter, temporalis, and lateral pterygoid muscle cardiac myosin heavy chain is found in fibres that contain either fast, or fast and slow myosin heavy chain. In rabbit masseter, temporalis and digastric muscles, fibres are present that express cardiac myosin heavy chain either exclusively, or concomitantly with slow myosin heavy chain or fast myosin heavy chain. Our results demonstrate a much broader distribution of cardiac myosin heavy chain than hitherto recognized and these might explain in part the specific characteristics of masticatory muscles. The cardiac myosin heavy chain is only found in skeletal muscles originating from the cranial part of the embryo (including the heart muscle) suggesting that its expression might be determined by the developmental history of these muscles.     

Inheritance and linkage of isozyme loci in almond

The segregation of seven isozyme marker genes was investigated using eight controlled crosses in almond. The cultivar Nonpareil was the maternal parent in all crosses. Pollination was achieved using eight different cultivars, and a total of 3200 individual kernels were assessed. For each isozyme the goodness-of-fit test was used to test for departure from the expected frequencies assuming Mendelian inheritance. Given a higher than expected number of significant results for individual isozymes, independent segregation between pairs of isozymes was tested using the chi-square statistic on the resulting two-way contingency tables. In all crosses a highly significant association (P value< 0.001) was observed between (1) the AAT- 1 and IDH isozymes loci and (2) the LAP-1 and PGM-2 isozymes loci, which leads to the conclusion that the respective isozyme pairs are linked.In addition, a significant association (P value < 0.001) was observed between LAP-1 and GPI-2 when the pollen sources were Fritz, Mission, or Price, but this could not be tested for the remaining five pollen sources, Carmel, Grant, Keane, Ne plus Ultra, Peerless, because they are homozygous at these loci. If LAP-1 is linked with GPI-2 and PGM-2, it might be expected that we should find evidence of linkage between GPI-2 and PGM-2. The lack of a significant association between these two isozymes suggests that LAP-1 is located centrally on the chromosome. These three pairs of linked loci are the first to be reported in almond.     

“Feed a cold,starve a fever” — folk models of infection in an english suburban community,and their relation to medical treatment

This paper outlines a widely-held conception of illness, related to perceived changes in body temperature — Chills and Colds on one hand, Fevers on the other — in an English suburban community on the outskirts of London. The relationship between this folk model, and that of the local family physicians is analysed, to show how biomedical treatment and concepts, particularly the germ theory of disease, far from challenging the folk model, actually reinforce it. Remedies which cannot be scientifically and biomedically justified are nevertheless prescribed by the physicians to meet their patients' need to make sense of biomedical treatment in terms of their folk model of illness. At the interface between physician and patient, biomedical diagnoses and treatment are more negotiable than previously realised — and this has important implications for the delivery of health care.     

Soybean seedling emergence at high temperatures

Bragg and Cobb soybean [Glycine max (L.) Merr.] seeds were germinated in sand at temperatures ranging from 25 to 40°C. Emergence decreased with increasing temperature above 37°C, with virtually no emergence at 40°C. Emergence of 12 other cultivars at 38°C ranged from 25 to 95%. Foster and Coker 338 were more sensitive to high temperature than the other cultivars.