Somatic embryogenesis in Sitka spruce (Picea sitchensis (Bong.) Carr.)

Embryonal-suspensor masses from immature embryos from cones of Sitka spruce (Picea sitchensis (Bong.) Carr.) proliferated on a modified Murashige & Skoog medium with N⁶-benzyl-aminopurine, kinetin, 2,4-dichlorophenoxyacetic acid and an organic nitrogen source. The slimy white embryonal-suspensor masses with proembryos were maintained on a solid proliferation medium with reduced amounts of growth regulators. Transfer of embryonal-suspensor masses to a non-woven polyester carrier with liquid maturation media containing ±2-cis-4-trans-abscisic acid and a reduced amount of inositol and organic nitrogen resulted in synchronized embryo formation. Further development was achieved on a medium without ±2-cis-4-trans-abscisic acid and organic nitrogen. Somatic embryos were successfully transferred ex vitrum.Abbreviations ABA ±2-cis-4-trans-abscisic acid - BAP N⁶-benzyl-aminopurine - ESM embryonal-suspensor masses - KIN kinetin - 2,4-D 2,4-dichlorophenoxyacetic acid     

Symbiosis-stimulated chitinase isoenzymes of soybean (Glycine mas (L.) Merr.)

Isoforms of endochitinase in soybean were studied in relation to root symbiosis. Five selected cultivars differing in their nodulation potential were inoculated with two strains of Bradyrhizobium japonicum, the broad host-range Rhizobium sp. NGR234, and with the mycorrhizal fungus Glomus mosseae. Total chitinase activity in nodules was up to 7-fold higher than in uninoculated roots and in mycorrhizal roots. The chitinase activity in nodules varied depending on the strain-cultivar combination. On semi-native polyacrylamide gels, four acidic isoforms were identified. Two isoforms (CH 2 and CH 4) were constitutively present in al analysed tissues. The other two isoforms (CH 1 and CH 3) were strongly induced in nodules and were simulated in mycorrhizal roots as compared to uninoculated roots. The induction of CH 1 varied in nodules depending on the soybean cultivar. This isoform was also stimulated in uninfected roots when they were treated with tri-iodobenzoic acid, rhizobial lipochitooloigosaccharides (Nod factors) and chitotetraose. CH 3 was not affected by these stimuli indicating that this isoform could represent a marker for enzymes induced in later stages of the symbiotic interactions.Key words: (Brady)rhizobium, chitinase isoenzymes, mycorrhiza, (restricted) nodulation, Nod factors      

Root-Tiller Interrelationships in Spring Barley (Hordeum distichum (L.) Lam.)

Root-tiller relations were investigated in spring barley grownin soil in deep pots. The total dry wt of the root system reachedits maximum 6 weeks from sowing, when the shoot weight was only50 per cent of its value at maturity. Seminal and nodal rootscomprised 40 and 60 per cent, respectively, of the total rootdry wt at maturity; the majority of the nodal root weight wasassociated with the main shoot. The main shoot had approximatelytwice as many nodal roots as either of the first two primarytillers (T1 and T2), and the primary and secondary tillers appearinglater were very poorly rooted. Some tillers, especially secondarytillers that died prematurely, produced no nodal roots. Theweight of the seminal roots and nodal roots attached to themain shoot continued to increase up to maturity but the drywt of nodal roots on tillers declined with time. This patternof growth was closely related to the pattern of ¹⁴C assimilateddistribution within the root system. A very small proportionof ¹⁴C assimilated by the main shoot and T1 and T2 was exported.The majority of the exported assimilate went to the seminalroot system and to nodal roots attached to the main shoot. Individualnodal and seminal roots seemed to have different roles in supplyingnutrients to the shoot system, with the former mainly providing³²P-phosphate to its tiller of origin and the latter generallysupplying the main shoot and primary tillers. Hordeum distichum. (L.) Lam., barley, root growth, nodal roots, seminal roots, tillering, assimilate distribution, ³²P-distribution     

Ein Beitrag zur Systematik der Sojabohnen (Glycine max (L.) Merr.)

Ohne ZusammenfassungHerrn ProfessorStubbe in Dankbarkeit zum 60. Geburstag.     

Intergeneric hybridization of marguerite (Argyranthemum frutescens (L.) Sch. Bip.) and Roman chamomile (Chamaemelum nobile (L.) All.) using ovule culture and confirmation of hybridity

To introduce useful characteristics such as fragrance into Argyranthemum frutescens (L.) and to expand the variation, we conducted crosses using A. frutescens as the seed parent and Chamaemelum nobile (L.) All. as the pollen parent. All the tested cross combinations between the three strains of A. frutescens and one strain of C. nobile produced embryos, and healthy plants were obtained by ovule culture. The obtained plantlets had a white ray floret, and the leaf shape was intermediate to those of the parents. The individuals obtained from this cross were subjected to two methods to determine hybridity: flow cytometry analyses and cleaved amplified polymorphic sequence (CAPS) markers. For the CAPS marker, we selected the internal transcribed spacer (ITS) region, which is highly variable among the genera, as the region to be amplified. We selected restriction enzymes BmgT120 I and Afl II, which selectively cut common sequences in the genus Argyranthemum, based on the sequence analysis of one parent strain each of A. frutescens and C. nobile and alignment with known sequences of related species. Flow cytometry analyses and CAPS markers revealed that the individuals obtained from the cross between A. frutescens and C. nobile are intergeneric hybrids. In addition, these established methods were capable of quickly and reliably identifying hybrids between A. frutescens and C. nobile. This report shows for the first time that crossbreeding between A. frutescens (seed parent) and C. nobile (pollen parent) is possible, and further development of Argyranthemum breeding, such as the expansion of variation by intergeneric crosses, is expected.     

The calcium nutrition of bambara groundnut (Vigna subterranea (L.) Verdc.)

Iron chlorosis induced by Fe-deficiency is a widespread nutritional disorder in many woody plants and in particular in grapevine. This phenomenon results from different environmental, nutritional and varietal factors. Strategy I plants respond to Fe-deficiency by inducing physiological and biochemical modifications in order to increase Fe uptake. Among these, acidification of the rhizosphere, membrane redox activities and synthesis of organic acids are greatly enhanced during Fe-deficiency. Grapevine is a strategy I plant but the knowledge on the physiological and biochemical responses to this iron stress deficiency in this plant is still very poor. In this work four different genotypes of grapevine were assayed for these parameters. It was found that there is a good correlation between genotypes which are known to be chlorosis-resistant and increase in both rhizosphere acidification and Fe^III reductase activity. In particular, when grown in the absence of iron, Vitis berlandieri and Vitis vinifera cv Cabernet sauvignon and cv Pinot blanc show a higher capacity to acidify the culture medium (pH was decreased by 2 units), a higher concentration of organic acids, a higher resting transmembrane electrical potential and a greater capacity to reduce Fe^III-chelates. On the contrary, Vitis riparia, well known for its susceptibility to iron chlorosis, fails to decrease the pH of the medium and shows a lower concentration in organic acids, lower capacity to reduce Fe^III and no difference in the resting transmembrane electrical potential. H Marschner Section editor     

Fusarium moniliforme Sheld. In Israel (Gibberella Fujikuroi (Saw.) Wollenw.)

In studies with 58–76 Israeli isolates and 5–9 foreign isolates ofF. moniliforme, growth in vitro on wheat and PDA was best at 24–30° C, with little growth at 6° C and none at 40° C. In the optimal temperature range, equal growth was made in light and darkness. F. moniliforme is widespread in agricultural soils in Israel, but in some 170 samples rarely exceeded about 5 % of the totalFusarium population.Of seventy-six Israeli and nine foreign isolates, seventy-four induced toxic reactions on rabbit skin. This is an unusually high proportion. The histological changes induced by such skin application are described.Inoculation tests were performed with eighty-three Israeli isolates from six field and five fruit crops, and with thirteen foreign isolates (including six from varieties ofF. moniliforme) on ten crop plants. Onions and all dicotyledonous plants tested were affected by a high proportion of the isolates, while wheat was not, and maize was little affected. There was therefore little pathogenic specialization among these isolates.The studies carried out in Israel onF. moniliforme as cause of the black heart disease of banana fruits and of fruit rots of avocado and citrus are reviewed.Morphological studies of all Israeli isolates and of those received from abroad, and a survey of the literature on the taxonomy of the Liseola section ofFusarium, have led to the following conclusion: The section should containF. moniliforme as its only species, andF. moniliforme var.anthophilum andF. moniliforme var.subglutinans as its only two varieties.From the present distribution ofF. moniliforme and its environmental relationships it is concluded that this fungus constitutes a potential danger to crops in warm countries to which irrigation is being introduced, and especially to dense plantation crops.

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Zusammenfassung In vitro Wachstum von 58–76 Isolierungen derF. moniliforme aus Israel und aus anderen Ländern, auf Weizenkörnern und PDA, war optimal bei 24–30° C; bei 6° C entwickelte sich der Pilz kaum, und bei 40° C überhaupt nicht. Bei den optimalen Temperaturen war das Wachstum in Licht und Dunkelheit gleich gut. F. moniliforme ist in den Agrarböden Isracls weit verbreitet, jedoch überschritt der Pilz in 170 Bodenproben nur selten 5 % der gesamtenFusarium Bevölkerung.Von 76 Isolierungen aus Israel und 9 aus dem Ausland erregten nicht weniger als 74 Isolierungen toxische Reaktionen als sie auf die Haut von Kaninchen aufgetragen wurden. Die histologischen Aenderungen, die durch solches Auftragen bewirkt werden, werden hier beschrieben.Infektionsversuche an 10 Agrarpflanzen wurden mit 83 Isolierungen aus Israel und 13 aus dem Ausland durchgeführt. Alle Dicotyledone sowie Zwiebeln wurden von vielen dieser Isolierungen befallen, dagegen wurde Mais selten und Weizen fast gar nicht befallen. Es konnte daher nur eine geringe pathologische Spezialisierung unter den Isolierungen vonF. moniliforme festgestellt werden.In Israel ausgeführte Forschungen überF. moniliforme als Erreger der Black Heart Fäule von Bananen Früchten und von Avokado- und Zitrusfruchtfäulen werden hier besprochen.Morphologische Studien an Isolierungen aus Israel und dem Ausland, und eine Literaturübersicht der Liseola Sektion führten zur folgenden Schlussfolgerung: Diese Sektion sollF. moniliforme als ihr einziges Spezies enthalten, undF. moniliforme var.anthophilum sowieF. moniliforme var.subglutinans sind als Varietäten anzuerkennen.Die gegenwärtige Verbreitung vonF. moniliforme und seine Umweltsbeziehungen lassen darauf schliessen, dass dieser Pilz in warmen Ländern in denen Bewasserung eingeführt wird, eine Gefahr für verschiedene Agrarplfanzen, insbesondere dichte Pflanzungen, darstellt.

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The support given this study by the Central Research Fund of the Hebrew University is gratefully acknowledged.     

Potassium and magnesium relationship in cowpea (Vigna unguiculata (L.) Walp.)

Summary The effects of K and Mg application on dry matter yield and uptake of K, Mg and Ca in cowpea were studied in greenhouse at Haryana Agricultural University, Hissar (india). Dry matter yields of leaves, stems and roots increased by 17, 30 and 27 per cent over control due to application of 150 ppm K and 17, 16 and 26 per cent by 40 ppm Mg respectively. Potassium application has antagonistic effect on Ca concentration of leaves, stems and roots and synergistic on root Mg concentrations upto 25 ppm K. However, Mg had a synergistic effect on concentration of K upto 20 ppm Mg and antagonistic at 40 ppm Mg in all plant parts. Uptake of K, Mg and Ca increased by Mg application, but K increased only K uptake.     

The Research of Gmelin Larch (Larix gmelinii (Rupr.) Rupr.) Gum

Russian Journal of Bioorganic Chemistry - The samples of Gmelin larch (Larix gmelinii (Rupr.) Rupr.) gum, selected from a variety of trees and from different parts of the tree in vicinity of...     

Inheritance of dwarfness in pigeon pea (Cajanus cajan (L.) millsp.)

Summary A mutant pigeon pea, showing dwarf and bushy growth, very late maturity, poor yield and abnormal flowers was isolated from the tall variety, Brazil P/2. It is proposed that the mutant be called dwarf.A single recessive gene appears to be responsible for dwarfness and seems to have pleiotropic effect on maturation. The symbol proposed for the dwarfness gene is d.

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Zusammenfassung Aus einer hochwüchsigen Straucherbse (Cajanus cajan (L.) Millsp.) der Sorte Brazil P/2 wurde eine Mutante mit verzwergtem und buschigem Wuchstyp, sehr später Reife, geringer Ertragsfähigkeit und abweichender Blütenform isoliert, für die der Name dwarf vorgeschlagen wird.Nur ein rezessives Gen scheint für den Zwergwuchs verantwortlich zu sein, das einen pleiotropen Effekt auf die Reife ausübt. Für dieses Gen wird das Symbol d vorgeschlagen.