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.     

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.     

Transmission of primary trisomics in pearl millet

Summary Transmission rates of extra chromosomes found in the full set of trisomics of pearl millet (Pennisetum americanum) (2n = 14) were estimated by examining the progeny of selfed trisomics and the progeny of trisomics crossed to disomics. When the trisomics were selfed, dark green and tiny had the highest transmission rate (23.8% and 23.3%, respectively) and pseudonormal the lowest (13.8%). Other trisomics had an intermediate rate of transmission. When the trisomics were used as females in crosses with disomics, both dark green and tiny again had the highest transmission rate and pseudonormal the lowest. When the trisomics were used as males in crosses to disomics, no trisomic was transmitted to the progeny except for spindle, and this occurred with a very low frequency (2.0%). A variation in transmission rate was observed from plant to plant and season to season for the same trisomic type. A study of the transmission rate of the extra chromosomes indicated that the following factors were probably contributing to the lower rate of transmission: small- or light-weight seeds tended to have a higher proportion of trisomics than heavier seeds; lighter seeds had a lower percentage germination; a positive and significant correlation was noticed between trivalent frequency and transmission rate. Plants with reduced vigour produced a higher frequency of trisomics. Though trisomics involving longer extra chromosomes showed a high degree of pollen and ovule sterility, they were highly transmissible. This has resulted in a close relationship between gametic sterility and transmission rate of extra chromosome.     

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.     

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     

Time of detection of recessive genes: effects of system of mating and number of examined individuals

Summary Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, Siete Cerros 66 and Penjamo 62, as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of Penjamo 62 in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.     

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.     

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.     

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.     

The effect of some macronutrients on adventitious root development on scion apple cultivars in vitro

The influence of some macronutrients, especially NH₄NO₃ and KNO₃, on root development of microcuttings from 3 apple scion cultivars is discussed. A reduction of the level of NH₄NO₃ in the medium from full strength to 1/4 strength significantly increased the percentage rooting of Gala and Royal Gala, but not Jonagold. Further reduction of NH₄NO₃ level from 1/4 strength to zero significantly reduced the percentage of rooting in Gala but not Royal Gala. Jonagold rooted best at zero concentration NH₄NO₃. Without NH₄NO₃, rooting percentages were as high as 100% for all 3 cultivars when KNO₃ was provided at full strength. The results show that adventitious roots can be induced on apple scion cultivars by media manipulation.     

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.     

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.     

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.     

High-level Expression of Maize <Emphasis Type="Italic">γ</Emphasis>-zein Protein in Transgenic Soybean (<Emphasis Type="Italic">Glycine max</Emphasis>)

Primers were developed for 118 microsatellites isolated from grape (Vitis vinifera) genomic libraries enriched for (AC)n repeats. Only one microsatellite sequence matched other grape SSR-sequences in the GeneBank database. Genotyping was carried out in the parental lines and four offspring of two pseudo-test-cross populations, Cabernet Sauvignon x Seyval and Chardonnay x Bianca, and a further six other grape genotypes (V. vinifera Sultanina, Merlot, Syrah, Müller-Thurgau, Vitis Regent and V. riparia Gloire de Montpellier). A total of 108 microsatellites showed easily scorable alleles and 100 of them segregated according to a configuration suitable for mapping in either cross. A further 8 SSRs, although unsuitable for mapping in those crosses, showed polymorphism in the other genotypes tested. This set of markers was used, along with 75 microsatellites of other repeat-types, to fingerprint 46 offspring of the cross Chardonnay x Bianca. For each full-sib, individual heterozygosity and distance in repeat units between pairs of alleles at each locus (mean d²) were calculated as a tool for predicting highly outbred recombinant individuals. Six microsatellites with segregation ratios significantly distorted towards the lack of homozygous sibs were identified and mapped to linkage groups LG 3 and LG 5. Estimation of heterozygosity at genome-wide level and genotyping at loci for which homozygous sibs are discriminated against are discussed for marker-assisted background selection in outcrossing grapevines.     

Genetic analysis of two wheat cultivars, ‘Sonalika’ and ‘WL 711’ for reaction to leaf rust (Puccinia recondita)

Summary Genetic analysis for leaf rust reaction of two widely adapted cultivars, Sonalika and WL 711, has been done using 21 near isogenic Lr lines and rust culture IL004 — avirulent on the two cultivars and all the Lr lines used. The segregation pattern in the F₂ generation indicated the presence of a recessive gene in Sonalika and of a dominant gene in WL 711. These genes in cultivars Sonalika and WL 711 have been identified as Lr 11 and Lr 13, respectively. Gene Lr 13 is no longer effective in WL 711 but it continues to give field resistance in the backgrounds of Chris, Prelude and Thatcher. There has been no significant change in the virulence spectrum of the leaf rust pathogen in India with the release of WL 711. High susceptibility of WL 711 seems to be due to the evolution of more aggressive forms of the pathogen to this cultivar. The gene Lr 11, which behaves as a recessive in Sonalika, was effective against leaf rust when this cultivar was released. The high susceptibility of Sonalika is probably due to an increase in the frequency of race 77 virulent on Lr 11. Lr 11 has shown a dominance reversal in the background of Sonalika. Present results suggest that interaction of resistance genes with the background genotype must be studied for their effective use in breeding programme.     

A theory of the origin of life

Life on Earth is essentially nucleic acids (NAs) influencing peptide synthesis such that NA replication is favored. It is proposed that the ability to synthesize polypeptides evolved gradually — one peptide bond at a time. The proposed evolution of the peptide synthesis apparatus begins with a transfer NA (tNA) which catalyzes the transfer of activated amino acids to accessible amino groups in its environment. The resulting capped molecules (with single amino acid caps) in turn favor NA replication. The proposed evolution of the peptide synthesis apparatus from the tNA onward is characterized by a progressive increase in the number of amino acids per cap: two tNAs jointly produce a dipeptide cap, three tNAs jointly produce a tripeptide cap, etc. Messenger NAs evolve because they can specify the composition and sequence order of the peptide caps. Lastly, ribosomal NAs evolve. The origin, expansion, and standardization of the genetic code are discussed. It is proposed that the present triplet code evolved by a process of codon length refinement, and that originally codons of varying lengths were allowable, as were unassigned bases between codons. An environmental supply of activated compounds for early evolving entities is proposed. An environmental NA replication process via single template-directed bond formation events is proposed. An environmental retention and redistribution process is proposed to have acted as a functional substitute for the cell wall and cell division of early evolving entities.     

The mucin profiles of normal gastric mucosa, intestinal metaplasia and its variants and gastric carcinoma

Summary Human gastrectomy specimens, including 48 carcinomas and 25 selected benign cases showing extensive intestinal metaplasia (IM), were examined in detail histologically and histochemically. IM was classified into complete (type I), incomplete without sulphomucins (type IIA) and incomplete with sulphomucins (type IIB). Type IIB was associated with intestinal but not diffuse cancers (P<0.01) or benign lesions (P<0.01). The mucin profiles of IIB IM were similar to intestinal cancers with sulphomucins predominating overN-acetylsialomucins.O-acetylsialomucins were not seen in IIB IM or tumours but were observed in complete or type IIM. These findings suggest a histogenic link between incomplete IM secreting sulphomucins (or colonic metaplasia) and intestinal cancers of the human stomach.     

“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.     

Genetic diversity in relation to heterosis and combining ability in spring wheat

Summary Genetic diversity among ten varieties of spring wheat used as parents in a diallel cross was assessed through multivariate analysis (D²-statistics) and then related to heterosis and SCA effects of their hybrids. The parents fell into three groups. Group I contained the varieties, Nobre, Girua and Carazinho; group II contained Sonalika, Lyallpur and Pitic 62 and group III contained Indus 66, Balaka, Sonora 64rs and MSl. The varieties of group I were good general combiners, while the varieties of group III were poor combiners. Significant heterotic and SCA effects for yield and yield components were observed in the hybrids of the parents belonging to different groups but not in the same group. Genetic divergence between the parents had a positive relationship with heterosis and SCA effects of the hybrids.