Phenomenology of Psychoanalytic Data. A Biosemiotic Framework

In my continuing efforts to build a bridge between psychoanalytic findings and biosemiotics here, as in previous works, ‘biosemiotic’ refers to the hierarchy of meaning-forms (from biological to semiotic-organizations) underlying an updated psychoanalytic model of mind. Within this framework I present a broad range of bio-semiotic phenomena, processes, dynamics, defenses, and universal and unique internalized interpersonal patterns, that in psychoanalysis all commonly fall under the broad heading of the “Unconscious.” Reconceptualized as interpretive data within the purview of a psychoanalytic discourse-semantic this biosemiotic framework posits an epigenetic continuum of human meaning-organizations originating at basic organic levels, moving upward through biological, psycho-somatic and affective expression, proto-semiotic transmissions, represented forms, and finally to explicit linguistic signs and complex symbol systems. In addition to assuming an uninterrupted epigenetic continuum crystallizing in hierarchic organization, this framework accentuates the multilayered and increasingly condensed quality of higher more elaborate organizations of meaning in human communication, drawing attention to persisting biological undercurrents in implied sense, intent, and motivation, all of which impact on repressive/defensive mechanisms. Drawing from previous works (Aragno 1997, 2005, 2008a, b, Psychoanalytic Inquiry 29(1):30–47, 2009, Biosemiotics 3:57–77, 2010, 2011a, Signs 5:71–74, 2011b, Journal of the American Psychoanalytic Association, Centennial Paper, Special Centennial Issue 59(2):239–288, 2011b, Signs 5:29–70, 2011c) in which I labored to update and revise Freud’s first topographical theory of mind, this paper presents the phenomenology of unconscious ‘data’ for the purpose of introducing a diverse range of non-linguistic signifying forms from which psychoanalysts infer mental processes and ‘interpret’ meanings. An important underlying premise regarding psychoanalytic data and its relation to the basic biosemiotic ‘agenda’ is that until grounded in an updated developmental theory of mind inclusive of pre- and proto-semiotic-forms, that is evolutionarily plausible, epistemologically based, and correlates with contemporary neuroscience, the term “sign” is merely an abstract linguistic ‘label’ rather than a mental act with antecedent developmental stages manifesting meanings through different forms and modes of expression. Drawn from the yields of the psychoanalytic method and semantic this revised metatheoretical approach provides insights into the sensory-emotive, bodily origins of unconscious layers of non-linguistic signification thereby expanding our understanding of the formative stages of the ‘semiotic function’ in human evolution. This being the third in a series of papers integrating the yields of psychoanalytic methodology with the underlying premises of ‘Biosemiotics,’ some familiarity with the background knowledge provided in the previous two is strongly recommended.     

‘Steps’ to Agency: Gregory Bateson,Perception, and Biosemantics

Gregory Bateson was welcomed into Biosemiotics as one of its precursors along with C. S. Peirce and Jacob von Uexküll He certainly endorsed Peirce pragmatic concern with learning as an essential characteristic of mammalian life, and also endorsed von Uexküll’s notion that the fundamental unit of animate existence is organism plus econiche. But he was at odds both with the subjectivism and with the cognitivism that connects Peirce to von Uexküll. Bateson rests his case on information theory which, he believes replaces many metaphysical notions that were the background to Peirce and von Uexküll’s approaches to ‘meaning.’ His idea of cybernetic ‘feedback’ in information circuits or networks yields a new understanding of recursiveness. Yet biofeedback in mammalian interaction had to be wrestled away from technical cybernetics and its thermodynamic rules about information, for the latter payed no attention to ‘meaning’ (“Bioentropy” section). Of the contrasts between Peirce and Bateson, the most significant is that Bateson regards ‘difference’ as primary to perception, while Peirce is concerned with continuity as primary from perception to cognition. This contrast is at the heart of Bateson’s Korzybski Lecture (see “On the Title of ‘Steps’” section), and shows how ‘difference’ in Learning develops orders and levels (see “Memory and Learning” section) leading to different categories of learning. With regard to perception, Bateson argues that the processes of perception do not bind perception to conscious awareness in any exclusive sense. Further, patterns of perception are not bounded by the skin for they include all external pathways along which information can travel. This recursive activity develops ‘agency’ (“Perception and Consciousness” section). We are ourselves interact with living mental ‘things’ but interactions with animate ‘creatura,’ is not the same as the objective interactions we purse in measuring inanimate material ‘things’ (pleroma) (“How Bioentropy Informs Bateson’s Notions of Pleroma and Creatura ” section). The grasping of context in communicative interaction, for example, is unique to creatura (“Context in Recursive Communication” section). Recognition of ‘difference’ occurs through communicative interactions and is meta-physical (without dimension). The pattern of interaction is the ‘thing,’ and ostensive aspects of communication are contextual, inclusive of all ‘external’ aspects vital for interpretation of ‘signals’ between initiators and responders to messages. Towards the end of his life, Bateson’s concerns with non-human conditions of ‘meaning’ and ‘mind’ in nature, resulted in his dropping several of the Peirce’s conditions of semiosis, as he looks at ‘meaning’ without language. He rests his method the propositional order of Peirce’s abduction rather than the latter’s full array of abduction, induction and deduction. Bateson is supported by the Biosemantics of Ruth Millikan, this paper will argue, who also believes that the derivation of meaning in animals through natural signs requires the stripping away of any ‘meaning rationalism’ (“Meaning Rationalism” section). Together they provide joint conclusions about as sign use in the ecosystems of creatura (“Conclusion” section).     

Where Does Pattee’s “How Does a Molecule Become a Message?” Belong in the History of Biosemiotics?

Recalling the title of Yoxen’s classical paper on the influence of Schrödinger’s book, I analyze the role that the work of H. Pattee might have played, if any, in the development of Biosemiotics. I take his 1969 paper “How does a molecule become a message?” (Developmental Biology Supplement) as a first target due to several circumstances that make it especially salient. On the one hand, even if Pattee has obviously developed further his ideas on later papers, the significance of this one springs out right from the title, the journal and date of publication and, of course, its content. On the other, this paper in particular has been somehow rediscovered recently and not only within the frame of biosemiotics (eg, in history and philosophy of biology by E.F. Keller). Following the parallelism with Yoxen’s perspective, I contend that Pattee’s work was relatively influential with respect to a good amount of attempts to rethink living systems within theoretical biology around the 70s. This influence diminished together with the decay or even collapse of those attempts under the impact of molecular biology as it was being developed those years. Eventually, Pattee’s work has been taken up again. Notwithstanding, it is quite clear that Pattee himself was not intending to contribute specifically to Biosemiotics and that he was probably unaware of any such discipline, at least until recently. Then, we should as well ask (as Yoxen wonders with respect to Schrödinger) to which extent Pattee’s influence has been a direct one or rather an indication of the relevance of his ideas and the resonance of his hypotheses with those of biosemiotics. For this task I will sketch a few points of convergence and divergence and examine the work of some authors who either address directly this issue or have contributed significantly to build up the history of Biosemiotics.     

Litter quality and environmental controls of home‐field advantage effects on litter decomposition

The ‘home‐field advantage (HFA) hypothesis’ predicts that plant litter is decomposed faster than expected in the vicinity of the plant where it originates from (i.e. its ‘home’) relative to some other location (i.e. ‘away’) because of the presence of specialized decomposers. Despite growing evidence for the widespread occurrence HFA effects, what drives HFA is not understood as its strength appears highly variable and context‐dependent. Our work advances current knowledge about HFA effects by testing under what conditions HFA is most important. Using published data on mass loss from 125 reciprocal litter transplants from 35 studies, we evaluated if HFA effects were modulated by macroclimate, litter quality traits, and the dissimilarity between ‘home’ and ‘away’ of both the quality of reciprocally exchanged litters and plant community type. Our results confirmed the occurrence of an overall, worldwide, HFA effect on decomposition with on average 7.5% faster decomposition at home. However, there was considerable variation in the strength and direction (sometimes opposite to expectations) of these effects. While macroclimate and average litter quality had weak or no impact on HFA effects, home‐field effects became stronger (regardless of the direction) when the quality of ‘home’ and ‘away’ litters became more dissimilar (e.g. had a greater dissimilarity in N:P ratio; F_1,42 = 6.39, p = 0.015). Further, home‐field effects were determined by the degree of difference between the types of dominant plant species in the ‘home’ versus ‘away’ communities (F_2,105 = 4.03, p = 0.021). We conclude that home‐field advantage is not restricted to particular litter types or climate zones, and that the dissimilarity in plant communities and litter quality between the ‘home’ and ‘away’ locations, are the most significant drivers of home‐field effects.     

On the Origin of Language

Thomas Sebeok and Noam Chomsky are the acknowledged founding fathers of two research fields which are known respectively as Biosemiotics and Biolinguistics and which have been developed in parallel during the past 50 years. Both fields claim that language has biological roots and must be studied as a natural phenomenon, thus bringing to an end the old divide between nature and culture. In addition to this common goal, there are many other important similarities between them. Their definitions of language, for example, have much in common, despite the use of different terminologies. They both regard language as a faculty, or a modelling system, that appeared rapidly in the history of life and probably evolved as an exaptation from previous animal systems. Both accept that the fundamental characteristic of language is recursion, the ability to generate an unlimited number of structures from a finite set of elements (the property of ‘discrete infinity’). Both accept that human beings are born with a predisposition to acquire language in a few years and without apparent efforts (the innate component of language). In addition to similarities, however, there are also substantial differences between the two fields, and it is an historical fact that Sebeok and Chomsky made no attempt at resolving them. Biosemiotics and Biolinguistics have become two separate disciplines, and yet in the case of language they are studying the same phenomenon, so it should be possible to bring them together. Here it is shown that this is indeed the case. A convergence of the two fields does require a few basic readjustments in each of them, but leads to a unified framework that keeps the best of both disciplines and is in agreement with the experimental evidence. What is particularly important is that such a framework suggests immediately a new approach to the origin of language. More precisely, it suggests that the brain wiring processes that take place in all phases of human ontogenesis (embryonic, foetal, infant and child development) are based on organic codes, and it is the step-by-step appearance of these brain-wiring codes, in a condition that is referred to as cerebra bifida, that holds the key to the origin of language.     

Studying hunting behaviour in the striped field mouse using data compression

We compare predatory behaviour towards a mobile insect in three species of small mammals: the granivorous striped field mouse, the insectivorous common shrew and the Norway rat (a generalist). The striped field mouse displays a surprisingly efficient hunting stereotype. We apply the data compression method (Ryabko et al. Theory Comput Syst 52:133–147, 2013) to compare the complexity of hunting behavioural patterns and to evaluate the flexibility of stereotypes and their succinctness. Norway rats demonstrated the highest level of complexity of hunting behaviour, with the highest proportion of ‘auxiliary’ and ‘noise’ elements and relatively low proportion of ‘key’ elements in their behaviours. The predominance of ‘key’ elements resulted in similarly low levels of complexity of hunting stereotypes in striped field mice and shrews. The similarity between hunting stereotypes of the insectivorous shrew and the granivorous striped field mouse enables us to argue about evolutionary roots of hunting behaviour in small mammals. We show that this method is a useful tool for comparing ethograms as ‘biological texts’.     

Equivocal locations: being ‘red’ in ‘Red Bologna’

This article addresses a classic ethnographic problem in the study of Italy: how is it that people can subscribe simultaneously to seemingly contradictory ideologies, such as Catholicism and Communism? It does so by describing examples from Italy's ‘showcase city’ of the left, ‘Red Bologna’, in which to be ‘red’ is ubiquitous but each person's ‘red’ is a different thing: being ‘red’ (differently) is the idiom in which real political distinctions are expressed over issues like religion or immigration. In parallel, I discuss the relationship between the ‘field’ as a location and the ‘field’ as a conceptual topic. My account replicates internal ethnographic differences at the analytical level by highlighting the differences between being left‐wing in Bologna and its meaning as a concept in anthropology. Hence the ‘equivocal location’: a field‐site that is productively different, from what an inexperienced ethnographer expected from it, from conceptual discussions in anthropology, and from itself.     

Diverse cellular colonizing endophytic bacteria in field shoots and in vitro cultured papaya with physiological and functional implications

The study was envisaged to assess the extent of normally uncultivable endophytic bacteria in field papaya plants and in vitro established cultures adopting cultivation vs molecular analysis and microscopy. Surface‐sterilized axillary shoot‐buds of papaya ‘Arka Surya’ revealed high bacterial diversity as per 16S rRNA metagene amplicon sequencing (6 phyla, 10 classes, 21 families) with an abundance of Pseudomonas (Gammaproteobacteria), which also formed a common contaminant for in vitro cultured field explants. Molecular analysis of seedling shoot‐tip‐derived healthy proliferating cultures of three genotypes (‘Arka Surya’, ‘Arka Prabhath’, ‘Red Lady’) with regular monthly subculturing also displayed high bacterial diversity (11–16 phyla, >25 classes, >50 families, >200 genera) about 12–18 months after initial establishment. ‘Arka Surya’ and ‘Red Lady’ cultures bore predominantly Actinobacteria (75–78%) while ‘Arka Prabhath’ showed largely Alphaproteobacteria corroborating the slowly activated Methylobacterium sp. Bright‐field direct microscopy on tissue sections and tissue homogenate and epi‐fluorescence microscopy employing bacterial DNA probe SYTO‐9 revealed abundant intracellular bacteria embracing the next‐generation sequencing elucidated high taxonomic diversity. Phylogenetic investigation of communities by reconstruction of unobserved states‐ PICRUSt‐ functional annotation suggested significant operational roles for the bacterial‐biome. Metabolism, environmental information processing, and genetic information processing constituted major Kyoto Encyclopedia of Genes and Genomes KEGG attributes. Papaya stocks occasionally displayed bacterial growth on culture medium arising from the activation of originally uncultivable organisms to cultivation. The organisms included Bacillus (35%), Methylobacterium (15%), Pseudomonas (10%) and seven other genera (40%). This study reveals a hidden world of diverse and abundant conventionally uncultivable cellular‐colonizing endophytic bacteria in field shoots and micropropagating papaya stocks with high genotypic similarity and silent participation in various plant processes/pathways.     

Morphological and molecular characterization of somaclonal variations in tissue culture-derived banana plants

In this study, 40 000 tissue culture-derived banana plants (vitroplants) at different growth stages, i.e. acclimatization, nursery and open field of banana (Musa spp.) cultivar ‘Grand Naine’ were screened for somaclonal variations using morphological investigations and molecular characterization. The total detected variants were grouped into 25 off-types (two of them died) in addition to the normal plant. Random Amplified Polymorphic DNA (RAPD) was carried out to study the differences among the normal cultivar ‘Grand Naine’ and its 23 variants using 17 arbitrary primers. Cluster analysis results revealed that ‘winged petiole’ and ‘deformed lamina’ were more related to the normal plant. However, ‘Giant plant’ and ‘weak plant’ related to each other and clustered with normal plant. According to principal coordinate analysis, most of the variants were aggregated nearly, whereas ‘variegated plant’ was separated apart from the other variants. This may reflect the genetic difference between ‘variegated plant’ and the other variants. The results obtained from both molecular and morphological analyses were in contiguous with better resolution when using the PCOORDA analysis than cluster analysis. Thus, it can be said that molecular markers can be used to eliminate the undesirable somaclonal variants from the lab without additional culture of the vitroplants in the field in order to save time and efforts.     

Intraspecific responses of medicinal plants: Genotype-environment interaction may alter drug quality of aromatic plants

An open field experiment was established in 2014 in Budapest (BP) and Poznań (PZ), which are characterized by different soil and weather conditions. The purpose was to study the intraspecific responses of Melissa officinalis L. (lemon balm -Lb) and Thymus vulgaris (thyme -T) to varying locations. Five accessions of lemon balm (‘Lorelei’, ‘Lemona’, ‘Soroksár’, ‘Quedlinburger Niederliegende’, ‘Gold Leaf’) and four of thyme (‘Sloneczko’, French Summer’, ‘Varico 3′, ‘Standard Winter’) were tested for yield and chemical characteristics.Biomass of both species was significantly higher in PZ, than in BP (291 and 107 g/plant for Lb and 105 and 53 g/plant for T in PZ and BP, respectively). In Lb, the environmental circumstances of the actual vegetation period of BP location were more favourable for the accumulation of volatiles (+76%), while the level of phenolic compounds was higher in PZ (up to +53% for rosmarinic acid). In T, each chemical parameter increased (up to +27% both for volatiles and total flavonoid content) in PZ, where lower temperatures and less precipitation prevailed.In most traits a significant interaction of genotype and growing location was established, which was more characteristic in T. The results show that breeding of specific cultivars for a given location might be of primary importance.     

Adrenergic signalling in osteoarthritis

Adrenoceptors (ARs) mediate the effects of the sympathetic neurotransmitters norepinephrine (NE) and epinephrine (E) in the human body and play a central role in physiologic and pathologic processes. Therefore, ARs have long been recognized as targets for therapeutic agents, especially in the field of cardiovascular medicine. During the past decades, the contribution of the sympathetic nervous system (SNS) and particularly of its major peripheral catecholamine NE to the pathogenesis of osteoarthritis (OA) attracted growing interest. OA is the most common degenerative joint disorder worldwide and a disease of the whole joint. It is characterized by progressive degradation of articular cartilage, synovial inflammation, osteophyte formation, and subchondral bone sclerosis mostly resulting in chronic pain. The subchondral bone marrow, the periosteum, the synovium, the vascular meniscus and numerous tendons and ligaments are innervated by tyrosine hydroxylase-positive (TH+) sympathetic nerve fibers that release NE into the synovial fluid and cells of all abovementioned joint tissues express at least one out of nine AR subtypes. During the past decades, several in vitro studies explored the AR-mediated effects of NE on different cell types in the joint. So far, only a few studies used animal OA models to investigate the contribution of distinct AR subtypes to OA pathogenesis in vivo. This narrative review shortly summarizes the current background knowledge about ARs and their signalling pathways at first. In the second part, we focus on recent findings in the field of NE-induced AR-mediated signalling in different joint tissues during OA pathogenesis and at the end, we will delineate the potential of targeting the adrenergic signalling for OA prevention or treatment. We used the PubMed bibliographic database to search for keywords such as ‘joint’ or ‘cartilage’ or ‘synovium’ or ‘bone’ and ‘osteoarthritis’ and/or ‘trauma’ and ‘sympathetic nerve fibers’ and/or ‘norepinephrine’ and ‘adrenergic receptors / adrenoceptors’ as well as ‘adrenergic therapy’.     

Proof of concept: nitrogen use efficiency of contrasting spring wheat varieties grown in greenhouse and field

Aims

Major aims were to test and evaluate a new concept for assessment of nitrogen use efficiency (NUE) of crops by growing six spring wheat varieties in greenhouse and field environments. NUE was calculated with a plant based concept integrating the entire crop life history and separating plant characteristics from environmental factors affecting NUE. Specific hypotheses were tested related to the varieties’ drought and nutrient fertilisation responses for NUE components, and coherence of those responses in field and greenhouse.

Methods

The wheat (Triticum aestivum L.) cultivated varieties ‘Diskett’, ‘Granary’, ‘Quarna’, ‘Stilett’, ‘Vinjett’, and a Swedish landrace (‘Dala’) were grown in field and greenhouse environments in Central Sweden. Two fertilisation treatments were included in a field and greenhouse experiment, and in the greenhouse also drought. The NUE components N uptake efficiency (U_N), grain-specific N efficiency (E_N,g) and grain N concentration (C_N,g) were assessed.

Results

Drought reduced yield and NUE through E_N,g, and more so when drought occurred prior to anthesis than after anthesis. Effect of fertilisation treatment on NUE components was similar in the two set-ups, but there were fewer variety × fertilisation interactions in the field. U_N was higher in the field and E_N,g was higher in the greenhouse, while C_N,g and overall NUE were similar in the two environments. Ranking of varieties regarding NUE and U_N was similar in the greenhouse and field, but different regarding E_N,g and C_N,g.

Conclusions

The NUE concept is a useful tool to describe and integrate important NUE components for crops grown in different treatments (nutrient fertilisation, drought) and experimental set-ups, i.e. greenhouse and field. Similar variety ranking in overall NUE across experimental set-ups indicates stable results in different environments.     

Effect of Nitrogen and Powdery Mildew on the Yield Formation of Two Winter Barley Cultivars1

In field experiments the effect of powdery mildew on the yield formation of two barley cultivars ‘Catinka’ (partially resistant) and ‘Tapir’ (susceptible) was investigated in relation to three levels of nitrogen fertilization (40, 90, 150 kg N/ha). Nitrogen increased especially the single ear yield of cv.‘Catinka’, whereas cv.‘Tapir’ showed symptoms of N oversupply. Infection density of Erysiphe graminis hordei also increased with increased nitrogen supply, although it decreased transiently, at the highest N level for cv.‘Tapir’. In general, cv.‘Catinka’ was less tolerant to infections with E. graminis than cv.‘Tapir’, but yield response of both cultivars to powdery mildew (17, 11 and 8 % and 12, 16, and 12 % yield losses for cv.,‘Catinka’ and ‘Tapir’. respectively) showed cultivar × nitrogen interrelationships. Starch and protein contents of grains indicated differences in the intensity of detrimental effects caused by powdery mildew limiting the formation of carbohydrates and/or the translocation processes. Regression analysis demonstrated a closer correlation of yield losses with the photosynthetically active leaf area (r =+0.96 and +0.93 for ‘Catinka’ and ‘Tapir’) than with disease intensity (r =−0.32 and −0.85). Theinte,rpretation of disease/yield loss relations and the detrimental effect of powdery mildew are discussed with reference to plant resistance, remaining green leaf area, the availability of nutrients, to ‘sink and source’ conditions and to the occurrence of,additional environmental stresses.     

Inheritance of resistance to lettuce root aphid in the lettuce cultivars 'Avoncrisp' and 'Lakeland"

The inheritance of resistance in two lettuce cultivars to lettuce root aphid, Pemphigus bursarius, was studied in a series of laboratory and field experiments at Wellesbourne between 1989 and 1992. A source of total resistance in the cv. ‘Avoncrisp’ which is linked to the downy mildew resistance gene Dm6, was shown to be governed by a single dominant gene. There were no maternal effects evident in the inheritance of this resistance. The basis of the high level of resistance which exists in the cv. ‘Lakeland’ (formerly known as ‘Jubilee’) was also shown to be controlled by the same dominant gene. The linkage between Dm6 and root aphid resistance was broken in ‘Lakeland’ as this cultivar does not possess the Dm6 gene. The linkage was presumably broken when the original cross between the parents of cv. ‘Lakeland’, ‘Calmar’ and ‘Avoncrisp’ was made. Under laboratory conditions small numbers of aphids commence development on cv. ‘Lakeland’ but colonies fail to develop and under field conditions the resistance provides adequate Protectión against the pest. The resistance in both ‘Avoncrisp’ and ‘Lakeland’ was effective against a population of lettuce root aphid collected from an endive crop in southern France as well as being effective against the Wellesbourne population of this aphid.     

Comparison in man of short latency averaged evoked potentials recorded in thalamic and scalp hand zones of representation

Recordings were performed in the thalamus of 13 patients suffering from either abnormal movements or intractable pain, with the aim of delimiting the region to be destroyed or stimulated in order to diminish the syndrome. In 11 of these patients averaged evoked potentials were recorded simultaneously from the scalp and specific thalamus (VP) hand area levels following median nerve stimulation. These recordings were done during the operation or afterwards when an electrode was left in place for a program of stimulation.The latencies of onsets and peaks on the scalp ‘P15’ were compared with those of the VP wave; a clear correspondence was found. Moreover, when increased stimulation was used, both waves began to develop in parallel. Thus in the contralateral ‘P15’ a component exists due to the field produced by the thalamic response. To explain the presence of an ipsilateral scalp ‘P15’ wave, we propose that a second wave having the same latency and a slightly shorter peak exists on the scalp due to a field produced by a brain-stem response. This double origin of ‘P15’ is also shown by the different changes which the ipsilateral and contralateral waves present during changes in alertness.The scalp ‘N18–N20’ is also composed of at least 2 components. The first peak appears on the scalp with a latency shorter than that of the negativity which develops in the thalamus. The N wave, moreover, increases in latency with rapid stimulus repetition. We propose with others that ‘N18’ is a cortical event reflecting the arrival of the thalamo-cortical volley. The second component, ‘N20,’ has a peak latency closely correlated to that of the thalamic negativity. This component was present alone in ‘N’ when rapid stimulation (> 4/sec) was used, which did not change the thalamic response. It must be a field produced by the thalamic negativity.     

Heterologous expression of <Emphasis Type="Italic">PDH47</Emphasis> confers drought tolerance in <Emphasis Type="Italic">indica</Emphasis> rice

Jerusalem artichoke (Helianthus tuberosus L.) cultivars are conserved in genebanks for use in breeding and horticultural research programs. Jerusalem artichoke collections are particularly vulnerable to environmental and biological threats because they are often maintained in the field. These field collections could be securely conserved in genebanks if improved cryopreservation methods were available. This work used four Jersualem artichoke cultivars (‘Shudi’, ‘M6’, ‘Stampede’, and ‘Relikt’) to improve upon an existing procedure. Four steps were optimized and the resulting procedure is as follows: preculture excised shoot tips (2–3 mm) in liquid MS medium supplemented with 0.4 M sucrose for 3 days, osmoprotect shoot tips in loading solution for 30 min, dehydrate with plant vitrification solution 2 for 15 min before rapid cooling in liquid nitrogen, store in liquid nitrogen, rapidly rewarm in MS liquid medium containing 1.2 M sucrose, and recover on MS medium supplemented with 0.1 mg L^?1 GA₃ for 3–5 days in the dark and then on the same medium for 4–6 weeks in the light (14 h light/10 h dark). After cryopreservation, Jerusalem artichoke cultivar ‘Shudi’ had the highest survival (93%) and regrowth (83%) percentages. Cultivars ‘M6’, ‘Stampede’, and ‘Relikt’ achieved survival and regrowth percentages ranging from 44 to 72%, and 37–53%, respectively. No genetic changes, as assessed by using simple sequence repeat markers, were detected in plants regenerated after LN exposure in Jerusalem artichoke cultivar ‘Shudi’. Differential scanning calorimetry analyses were used to investigate the thermal activities of the tissues during the cryopreservation process and it was determined that loading with 2.0 M sucrose and 0.4 M sucrose dehydrated the shoot tips prior to treatment with PVS2. Histological observations revealed that the optimized droplet vitrification protocol caused minimal cellular damage within the meristem cells of the shoot tips.     

Hybrid corn and the unsettled question of heterosis

George Shull’s 1908 seminal article ‘The composition of a field of maize’ marked the ‘exploitation of heterosis in plant breeding, surely one of genetics’ greatest triumphs’. Hybrid corn became a ‘symbol of American agriculture’ and ‘the paradigm for all developments of \(\hbox {F}_{1}\) hybrid crop varieties and more generally breeding. But there is still no consensus on the definition of heterosis while its biological basis, causal factors and genetic mechanisms remain ‘unknown’, or at best ‘poorly understood’. It is thus logical to reverse the usual approach from the exploitation of a mysterious heterosis to the triumph of hybrid corn and focus on what breeders and geneticists do rather than on the theoretical reasons for their success. This factual approach produces surprising results: (i) hybrid corn extends the isolation technique of autogamous cereals to the allogamous maize; (ii) a ‘hybrid’ is an ordinary corn plant made reproducible by the breeder and only the breeder. It is proprietary rather than ‘hybrid’; (iii) for all practical purposes, heterosis is irrelevant; (iv) Shull justified his ‘hybrid’ breeding method by the ad hoc argument of maize ‘hybrid vigour’ which in 1914, he conflated under the name of heterosis with Edward East’s concept of physiological stimulation due to heterozygosity; (v) hybrid corn can increase yield only once and by a small margin and (vi) the huge yield gains of the last 80 years came from mass selection, a process inconsistent with the theory of heterosis. In conclusion, the enduring success of ‘hybrid’ corn was achieved at the expense of farmers, common welfare and biodiversity and dovetails with the industrial agriculture requirements of crop uniformity and breeder monopoly over reproduction. This critical understanding of the paradigm of plant breeding could have important implications for breeders and geneticists.     

DMS dynamics in the most oligotrophic subtropical zones of the global ocean

The influences of physico-chemical and biological processes on dimethylsulfide (DMS) dynamics in the most oligotrophic subtropical zones of the global ocean were investigated. As metrics for the dynamics of DMS and the so-called ‘summer DMS paradox’ of elevated summer concentrations when surface chlorophyll a (Chl) and particulate organic carbon (POC) levels are lowest, we used the DMS-to-Chl and DMS-to-POC ratios in the context of three independent and complementary approaches. Firstly, field observations of environmental variables (such as the solar radiation dose, phosphorus limitation of phytoplankton and bacterial growth) were used alongside discrete DMS, Chl and POC estimates extracted from global climatologies (i.e., a ‘station based’ approach). We then used monthly climatological data for DMS, Chl, and POC averaged over the biogeographic province wherein a given oligotrophic subtropical zone resides (i.e., a ‘province based’ approach). Finally we employed sensitivity experiments with a new DMS module coupled to the ocean general circulation and biogeochemistry model PISCES to examine the influence of various processes in governing DMS dynamics in oligotrophic regions (i.e., a ‘model based’ approach). We find that the ‘station based’ and ‘province based’ approaches yield markedly different results. Interestingly, the ‘province based’ approach suggests the presence of a ‘summer DMS paradox’ in most all of the oligotrophic regions we studied. In contrast, the ‘station based’ approach suggests that the ‘summer DMS paradox’ is only present in the Sargasso Sea and eastern Mediterranean. Overall, we found the regional differences in the absolute and relative concentrations of DMS between 5 of the most oligotrophic regions of the world’s oceans were better accounted for by their nutrient dynamics (specifically phosphorus limitation) than by physical factors often invoked, e.g., the solar radiation dose. Our ‘model based’ experiments suggest that it is the limitation of phytoplankton/bacterial production and bacterial consumption of DMS by pervasive phosphorus limitation that is responsible for the ‘summer DMS paradox’.     

The effect of dusk and dawn on the locomotor activity rhythm of Talitrus saltator (Montagu) (Crustacea: Amphipoda)

Entrainment of the nocturnal, endogenous locomotor activity rhythm of Talitrus saltator (Montagu) by the natural light-dark cycle is non-parametric, the phase of the rhythm shifting only in response to changes in the time of an experimentally simulated ‘dawn’ transition. The difference in response to light at ‘dusk’ and ‘dawn’ illustrates a phase-dependent responsiveness common to endogenous rhythms. Activity begins after complete darkness, with cessation always occurring during the ‘dawn’ transition and never continuing past the onset of total experimental illumination. The point of activity cessation is taken to be the position of a synchronizing cue controlling entrainment. The ‘dawn’ cue appears to be an absolute irradiance level of approximately 1.5 × 10^?4 W/m² (1.5 lux). The implications of such a cue are discussed in relation to field behaviour.     

A Screening Method for Detecting Resistance Against Cassava Bacterial Blight Disease

Inoculation of the cassava bacterial blight (CBB) pathogen by using a modified pair of tongs on cassava shoots (1-month-old) in the glasshouse and in the field resulted in symptoms within 24-48 h on susceptible cassava lines ‘02864’ and ‘M'pelolongi’. Gum exudates on inoculated young stems and die-back appeared 7-12 and 20-25 days later, respectively. No symptoms of CBB were observed on cv. ‘Kadanga Malombe’. Symptom development and CBB ratings on 3-month-old cassava shoots in the glasshouse and inthe field were not consistent. Inoculation of CBB pathogen on 521 cassava shoots (1-month-old) using the tongs method gave 81 and 82 resistant and moderately resistant plants to CBB, respectively. The tongs method is an excellent field-screening technique for detecting resistance to CBB on 1-month-old cassava shoots.