Response to salinity of three grain legumes for potential cultivation in arid areas

Abstract

The material balance of all the chemical species associated with the phosphate sorption reaction by two amorphous clays, silica-alumina gel and synthetic goethite was investigated adjusting the initial pH to 4.0, 5.0, 6.0, and 7.0. Phosphate sorption was found to decrease with increasing initial pH. During phosphate sorption, the equilibrium pH rose, adsorption of Cl^- decreased to a state of negative adsorption, adsorption of Na⁺ increased markedly, silicate was released, and Al in the solution was precipitated. With increasing initial pH, the amount of apparent released OH^- increased, the amount of Na⁺ adsorption increased, and the amount of released silicate decreased. The overall relationship of the material balance is explained in terms of the charge balance associated with phosphate sorption.     

Structural observations during androgenic microspore culture of the 4c1 genotype of Zea mays L.

Summary The capacity of the maize genotype 4c1 to regenerate microcalli and embryos from cultured microspores has been examined by comparing various cold pretreatments and culture media, using microspores and pollen at different stages of development. Viability of cultured cells was tested with FDA and their development was traced with light and fluorescence microscopy using DAPI as a nuclear dye.It was found that a pre-incubation of dissected flowers floating in a liquid nutrient medium at 8°C during 10–14 days was most successful for the induction of cell division. Among the developmental stages tested only the microspores appeared to regenerate. Subculture at 25°C in the same liquid medium, supplemented with 0.1 mg/l TIBA, gave highest rates of microspore division, i.e. up to 70% at 4 to 6 days of culture.All pathways described earlier for maize androgenic embryogenesis were observed within the 4c1 genotype. Symmetric divisions occurred in cultured microspores but most frequently asymmetric divisions lead to the formation of microcalli within 12 days of culture. In at least 60% of all dividing microspores cells were derived from the generative nucleus. Microcalli further developed either into loose or compact calli. Compact calli formed embryo-like structures.Abbreviations DAPI 4,6-diamidino-2-phenylindole - Dicamba 3,6-dichloro-2-methoxy benzoic acid - 2,4D 2,4 dichlorophenoxyacetic acid - FDA fluorescein diacetate - PAA phenylacetic acid - TIBA 2,3,5-triiodobenzoic acid - YP medium Yu-Pei basal salt medium     

Métabolisme glucidique de la racine de carotte cultivée (variété Nantaise demi-longue) au cours du cycle végétatif de la plante

Tuberisation of the carrot root is accompanied by a regular accumulation of soluble carbohydrates, greater in the case of saccharose than for glucose and fructose, so that very soon the reserve is principally disaccharide in nature. At first there is also slight formation of starch but it generally disappears by the end of autumn.The role of the tissues of the carrot root does not seem to be merely that of accumulating sugars provided by the leaves, but also of taking part to a certain degree in the synthesis of the saccharose that they contain. The formation of starch appears to be related to the osmotic pressure of the cells which rises with the increase of sugars.The ripening of carrots is not a well-defined physiological phenomenon. It may be regarded as corresponding to the time when the level of soluble sugars attains a constant value, even if the root continues to grow and consequently accumulate a further quantity of sugar.Development of the tuberous root and accumulation of sugars do not cease under the influence of climatic conditions, but depend on the date of sowing, as if they were limited by an ageing of the cells.Winter normally brings about a break in the development of the roots and a beginning of the utilisation of sugars. However, in plants sown late, the roots continue to grow and accumulate soluble sugars until mid-winter. A part of these sugars results from the hydrolysis of starch, but some are assimilated by the few green leaves that persist.In spring, vegetation is resumed after rehydration of tissues that were partly dehydrated during the accumulation of sugars. Formation of the flowering stalk is accompanied by the progressive disappearance of all sugars, which does not permit the attribution to any particular sugar of a specific biological role either in the formation of cell constituents or in the release of energy.It also appears that saccharose is not a merely passive form of reserve sugar, but that it is probably involved in certain reactions as a metabolite independent of the two reducing sugars.The period of flowering is independent of the time of sowing.In the tuberous root of the carrot, as in that of the sugar-beet and the rhizome of Jerusalem artichoke, the levels of ash and sugar vary inversely. The phenomenon has no biological significance, as claimed by certain authors, since the high rate of sugar accumulation affects the ratio only in a mathematical sense by reducing the relative percentage of ash.

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Zusammenfassung Die Wurzelbildung der Karotten wird begleitet von einer gleichmäßigen Zunahme löslicher Kohlenhydrate, wobei der Anteil der Saccharose stärker wächst als der der Glukose, so daß die Biose bald die Kohlenhydrat-Hauptreserve ist. Anfangs findet auch eine Bildung von Stärke statt, aber immer in sehr geringer Menge. Die Stärke verschwindet gegen Ende des Herbstes. Die Rolle des Karottengewebes scheint sich nicht nur auf die Anhäufung des durch die Blätter zugeführten Zuckers zu beschränken, sondern es nimmt auch in einem gewissen Maße Anteil an der Synthese der Saccharose, die im Gewebe enthalten ist. Die Bildung der Stärke scheint an die osmotische Spannung der Zelle, die sich immer durch den Beitrag des Zuckers erhöht, gebunden zu sein. Die Maturation der Karotte ist kein wohldefiniertes physiologisches Phänomen. Man kann sie als den Zeitpunkt beschreiben, in dem der Gehalt des löslichen Zuckers einen fast konstanten Wert erreicht, auch wenn die Speicherwurzel weiter wächst und dadurch neue Mengen an Kohlenhydraten anhäuft.Die Entwicklung der Wurzel und die Zunahme des Zuckers hört nicht unter dem Einfluß der klimatischen Bedingungen auf, sondern hängt ab vom Datum der Aussaat, als wäre sie begrenzt durch ein Älterwerden der Zellen.Im Winter stimmt normalerweise das Aufhören der Entwicklung der Wurzeln und der Beginn des Verbrauchs der Kohlenhydrate überein, während bei den Pflanzen, die später ausgesät werden, die Wurzeln noch wachsen und immer noch löslichen Zucker bis zur Mitte dieser Jahreszeit anhäufen. Ein Teil dieses Zuckers entstammt der Stärkehydrolyse, ein anderer bildet sich noch durch die chlorophyllische Assimilation, die in beschränktem Maße mittels einiger lebendig gebliebener Blätter fortdauert. Im Frühling beginnt die Wiederaufnahme des Wachstums mit einer Wiederhydratation der Wurzelgewebe, die während der Anhäufung der Kohlenhydrate teilweise ausgetrocknet waren. Die Bildung des blühenden Stengels wird begleitet von dem fortschreitenden Verschwinden sämtlicher Zucker, ohne daß man jedem eine biologische Rolle zuschreiben kann, sei es in der Bildung der Zellbestandteile oder in der Energieerzeugung. Es scheint auch, daß die Saccharose nicht nur als passive Reserve der reduzierenden Zucker angesehen werden darf, sondern daß sie wahrscheinlich wie ein Stoffwechselprodukt unabhängig von ihren beiden Bestandteilen in bestimmte Reaktionen eingreift.Die Blütezeit tritt unabhängig vom Zeitpunkt der Aussaat ein.In der Wurzel der Möhre sowie in der der roten Rübe und im Rhizom des Topinamburs verändern sich die Gehalte von Asche und Zucker umgekehrt. Dieses Phänomen hat keine biologische Bedeutung, wie bestimmte Autoren meinen, denn die starke Anhäufung der Zucker beeinflußt das Zucker-Asche-Verhältnis nur mathematisch gesehen infolge Herabdrücken des Prozentsatzes der Mineralstoffe.

     

A retrospective study of 29 cases of otitis media/interna in dairy calves

Epidemiological data, clinical findings, laboratory data, medical imaging, and outcomes were reviewed in 29 dairy calves with otitis media/interna. Age at admission ranged from 1 to 24 wk. The majority of calves were referred during winter. Clinical signs included drooping ear, ptosis, head tilt, abnormal nystagmus, strabismus, dysphagia, regurgitation, stiff neck, opisthotonos, facial hyperesthesia, and purulent aural discharge. Intranasal endoscopic examination of 5 animals revealed nasopharyngeal collapse in 4. Cerebrospinal fluid (CSF) was abnormal in all of 7 cases. Mycoplasma bovis was cultured from all but 1 case with external ear or tympanic bullae samples (n = 12), and Mycoplasma arginini was cultured from the remaining ear sample. Radiographs of the tympanic bullae were performed in 24 calves, tomodensitometry (CT) in 3 calves and ultrasound in 4 calves. According to medical imaging techniques or necropsy, 69% of the cases were classified as chronic. Mean duration of treatment was 23.3 d. The rate of clinical recovery was 75%.     

Revue des pratiques d'elevage de poissons en cages dans les eaux continentalesA review of fish cage culture as practised in inland waters

The rearing of fish in cages could greatly contribute to increasing fish production in existing inland waters. Although it presents numerous advantages, its limitations and possible inconveniences must be borne in mind. Well-developed technology is available mainly from the Democratic Republic of Germany, The Netherlands, Japan, the U.S.A., the U.S.S.R. and the Lower Mekong region. Research is currently pursued in numerous other countries, where the use of floating cages in fish culture is becoming increasingly diversified.The most popular fish species used in intensive cultural systems are Cyprinus carpio, Ictalurus punctatus and Salmo gairdneri. In the semi-intensive Asian systems, Barbus spp., Pangasius spp. and murrels are among the favourite cage-reared fishes. Tilapia aurea and Tilapia nilotica have also proved to be well adapted to cage culture. Polyculture is only rarely practised.Floating cages seem to be the best suited for fish culture in most cases. Net cages are the simplest in design and the cheapest to build. The escape of fish, however, always remains an eventuality which might lead to choosing more expensive designs. Maintenance of cages must be regular. For flexibility of exploitation, cages should not be too large. Their location within the water body can play an important role in keeping production high.At high stocking rates, artificial feeding of a well-adapted diet is a necessity. Optimum conversion rates require a well-adjusted daily ration, possibly fractioned. Mechanized feed distribution is to be encouraged as a labour-saving practice. Less intensive systems rely more on locally available wastes, such as trash fish, but the feeding rate then depends mostly on feed prices.Best growth is generally achieved by C. carpio and I. punctatus. Attainable maximum production is as high as 35 kg/m³/month under intensive management. However, generally, production averages from 5 to 30 kg/m³/month for these two species. S. gairdneri is less productive. T. aurea and T. nilotica have both a very good potential. Production in less intensive systems varies greatly according to management practices.     

Alien chromosome transmission and somatic elimination in monosomic addition lines of Gossypium australe F. Muell in G. hirsutum L.

The efficiency of using monosomic alien addition lines (MAALs) to introgress agronomical traits of interest carried by wild diploid Gossypium species into the main cultivated cotton species G. hirsutum depends on the opportunities of confronting the alien chromosome with the recipient background genome at each generation and on the occurrence of translocations and homoeologous recombinations. The selfed-progeny of five MAALs of G. australe in G. hirsutum was screened with SSR markers to determine the transmission frequency of the alien chromosome and monitor its integrity. Three MAALs revealed a transmission frequency significantly lower than the expected ratio and one MAAL presented an exclusive transmission of the additional chromosome. In these four MAAL the alien chromosome was transmitted almost unaltered. With the fifth MAAL the alien chromosome was normally transmitted but was altered in half of the plants carrying it. In one MAAL, normally carrying brown fiber, the emergence of some plants carrying white and brown fiber revealed the somatic elimination of the additional chromosome. The loss of this chromosome seems to be triggered by its deletion.     

Optimization of DH-line based recurrent selection procedures in maize under a restricted annual loss of genetic variance

Doubled haploid (DH) lines are increasingly being used in commercial hybrid maize (Zea mays L.) breeding. They allow for various quantitative genetic and logistic advantages provided that they are implemented in efficient and optimally allocated breeding procedures. In the present study, a new software was applied to optimize two recurrent selection (RS) schemes for hybrid maize breeding based on DH lines under a restricted annual budget and an upper limit for the relative annual loss of genetic variance. This software maximizes the expected gain from selection in general combining ability by means of quantitative genetic model calculations. Optimization results are compared for one, two, and three stages of testcross selection under different assumptions regarding the evaluation of lines per se and the annual budget. Results show that the optimum allocation of technical and budget resources to the individual steps of an RS program and the efficiency of alternative RS procedures are decisively determined by the number of selection stages. Under standard assumptions, one-stage selection was superior to two- and three-stage selection. Thus, shortening the length of an RS scheme considerably increases its efficiency. By intercrossing a reduced number of selected lines for starting a new RS cycle, the short-term response to selection may be increased, but the population size and, thus, the selection limits in the long run are diminished. Therefore, fair comparisons of alternative RS procedures require to define the intended time span for maximizing the genetic gain from RS and to restrict the relative annual loss of genetic variance accordingly.     

Allele mining and haplotype discovery in barley candidate genes for drought tolerance

In the present study, allele mining was conducted on a panel of drought related candidate genes in a set of 96 barley genotypes using EcoTILLING, which is a variant of the targeting induced local lesions in genomes (TILLING) technology. Analyzing approximately 1.5 million basepairs in barley a total number of 94 verified unique haplotypes were identified in 18 amplicons designed for 9 genes. Overall, 185 single nucleotide polymorphisms (SNPs) and 46 insertions/deletions (INDELs) were detected with a mean of 1SNP/92 bp and 1INDEL/372 bp genomic sequence. Based on overlapping haplotype sequences, markers were developed for four candidate genes (HvARH1, HvSRG6, HvDRF1, HVA1), which allows distinguishing between the main haplotypes showing either differences in amino acid sequence or which have larger INDELs in the promoter region. As “proof of concept”, the HvARH1 and HvSRG6 haplotypes were tested for the level of abscisic acid-induced gene expression in subsets of genotypes belonging to different haplotype categories. An integrated database was developed to contain information about the genes, genotypes, and haplotypes analyzed in this study. The database supplies profound information about the natural variation in the tested drought related candidate genes providing a significant asset for further mapping studies dealing with this highly polygenic trait.     

Construction of a crop—wild hybrid population for broadening genetic diversity in cultivated sunflower and first evaluation of its combining ability: the concept of neodomestication

The genetic base of sunflower elite lines is very narrow, due to many years of selection and breeding. To broaden the genetic diversity of the cultivated sunflower, in 1995 73 wild sunflower populations were crossed with 3 cultivated lines (Testers), and 219 hybrid offspring’s were evaluated in the field. GCA and SCA effects were computed suggesting for all traits a genetic potential for improvement through selection. Study of the hybrids revealed that the wild accessions bear different genetic abilities to combine with the testers for traits of morphological architecture, phenology and yield (seed weight and seed oil). The variance due to GCA and SCA showed that gene action was additive for days to flowering, branching and plant height. Genotypes derived from the same geographic origin may have either good or poor general combing ability. The correlation between GCA and per se genotype performance was positive for all traits except for seed oil content. This was the first attempt to evaluate wild-cultivated hybrids in sunflower on a large scale and will be the starting point for the management of hybrid Helianthus annuus populations for breeding. GCA and SCA estimations will facilitate the definition of strategies to manage and exploit the natural diversity for this crop.