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51.
Eleven accessions belonging to six species ofSolanum (S. bulbocastanum,S. chacoense, S. gourlayi, S. microdontum, S. papita, and S.sparsipilum) were tested for resistance to salt. Resistance was measured by survival and growth (dry weight of tops) of plants treated with solutions of NaCl and Na2SO4. The six species could be grouped into four classes based on good to poor resistance to salt solutions (1.S. chacoense, 2.S. gourlayi, 3.S. microdontum, S. sparsipilum, S. bulbocastanum and 4.S. papita). There was a close relationship (r=0.94**) between the survival of plants and growth of surviving plants treated with salt solutions. There was no relationship between known heat or drought resistance of various accessions and salt resistance. Results indicate there is a large genetic base available to improve the salt resistance of the cultivated potato.  相似文献   
52.
Potato plants (cvs. ‘Russet Burbank’, ‘Red Pontiac’, ‘Norchip’ and ‘Norgold Russet’) were grown in an artificial medium for 28 days under greenhouse conditions and were watered with solutions containing various rates of NaCl or Na2SO4 alone and in combination with CaSO4. NaCl and Na2SO4 slowed growth of young plants. On a mole basis Na2SO4 slowed growth more than NaCl. The addition of CaSO4 reduced the deleterious effect of NaCl or Na2SO4 solutions. Growth of ‘Russet Burbank’ plants was the most adversely affected by solutions of NaCl or Na2SO4. Watering with solutions of NaCl or Na2SO4 also reduced the number of ‘Russet Burbank’ plants.  相似文献   
53.
Summary The degree of inter- and intra-specific variation in the populations of allogamous and autogamousSecale L. species was estimated in support of isoenzyme markers. Totally, 11 different species ofSecale were analysed including perennial species:S. kuprijanovii Grossh.,S. chaldicum Fed.,S. montanum Guss.,S. anatolicum Boiss., and annual species:S. silvestre Host.,S. vavilovii Grossh.,S. ancestrale Zhuk.,S. dighoricum Vav.,S. afghanicum Vav.,S. segetale Roshev.; as well as the cultivated ryeS. cereale L. cv. Dakowskie Zote. Isoenzymes were analysed in the first leaf of single young seedlings grown in controlled conditions using starch-gel slab electrophoresis technique and the electrophoretic forms of two different enzyme systems were detected: nonspecific esterases (E. C. 3. 1. 1) and peroxidase (E. C. 1. 11. 1. 7). It was found that the breeding system of rye species has a distinct affect on the isoenzyme variation in their populations. The selffertile annual species,S. silvestre, was monomorphic for both enzyme systems. A very low esterases polymorphism was also found in other autogamous species,S. vavilovii, however a similar degree of polymorphism in allogamous annual species,S. segetale andS. dighoricum, was observed. Generally, the perennialSecale species were more polymorphic than the annual ones, and the isoenzyme variation in the population of cultivated ryeS. cereale was similar to some other wild annual species. It was observed that the intra-specific isoenzyme variation inSecale was bigger than the inter-specific. Esterases electrophoretic forms showed to be very sensitive markers of variation in rye species.
Isoenzym-Variation bei Wildarten der GattungSecale L.
Zusammenfassung Der Grad der inter- und intraspezifischen Variation in Populationen von allogamen und autogamen Arten der GattungSecale L. wurde mit Hilfe von Isoenzymmerkmalen geschätzt. Insgesamt wurden 11 verschiedene Arten vonSecale einschließlich der mehrjährigen Arten analysiert:S. kuprijanovii Grossh.,S. chaldicum Fed.,S. montanum Guss.,S. anatolicum Boiss. und die einjährigen Arten:S. silvestre Host.,S. vavilovii Grossh.,S. ancestrale Zhuk.,S. dighoricum Vav.,S. afghanicum Vav.,S. segetale Roshev., wie auch des KulturroggensS. cereale L. cv. Dankowskie Zote. Die Isoenzyme wurden am ersten Blatt junger Einzelsämlinge, die unter kontrollierten Bedingungen angezogen wurden, unter Anwendung der Stärkegel-Plattenelektrophorese-Technik geprüft, und die elektrophoretischen Formen von zwei verschiedenen Enzymsystemen wurden nachgewiesen: nichtspezifische Esterasen (E. C.3.1. 1.)und Peroxidase (E. C. 1. 11. 1. 7.). Es wurde gefunden, daß das Fortpflanzungssystem der Roggen-Arten eine bestimmte Wirkung auf die Isoenzymvariation in ihren Populationen hat. Die selbstfertile einjährige Art,Secale silvestris, war hinsichtlich beider Enzymsysteme monomorph. Ein sehr schwach ausgeprägter Esterasenpolymorphismus wurde in einer anderen autogamen Art,S. vavilovii, gefunden, jedoch wurde ein ähnlicher Grad von Polymorphismus in allogamen einjährigen Arten,S. segetale undS. dighoricum, beobachtet. Grundsätzlich waren die mehrjährigenSecale-Arten polymorpher als die einjährigen, und die Isoenzym-Variation der Populationen des kultivierten RoggensS. cereale war ähnlich der einiger anderer einjähriger Wildarten. Es wurde beobachtet, daß die intraspezifische Enzym-Variation vonSecale größer war als die interspezifische. Die esterase-elektrophoretischen Formen erwiesen sich als sehr empfindliche Indikatoren für die Variation der Roggenarten.

Secale L.
Secale L. . 11 ; :S. kuprijanovii Grossh.,S. chaldicum Fed.,S. montanum Guss.,S. anatolicum Boiss.; : S. silvestreHost,S. vavilovii Grossh.,S. ancestrale Zhuk.,S. dighoricum Vav.,S. afghanicum Vav.,S. segetale Roshev. S. cereale L., . , , ( — ). : (. . 3. 1. 1.) (. . 1. 11. 1. 7.). , ë . S. silvestre . ,S. vavilovii, ,S. segetale S. dighoricum. , , , . Secale , . .


Presented as poster  相似文献   
54.
In a pot trial in which soybean [Glycine max (L.) Merr.] plants were overfertilized by boron (B) at rates of 5, 10, and 15 mg per pot in 6 kg of soil, a reduction of shoot weight and seed yield was obtained. Boron limited protein synthesis and inhibited dipeptidase activity. Under the effect of B overfertilization, the rates of absorption and accumulation of major macronutrients was remarkably decreased. Foliar treatment with gibberellin (A3) in the early phases of plant development partly compensated for the negative effect of B overdosing.  相似文献   
55.
Summary

Four narcissus cultivars were forced under artificial light using fluorescent lamps which emitted white (307 – 770 nm), blue (393 – 580 nm), red (540 – 760 nm), yellow (450 – 750 nm), or green (387 – 680 nm) light. The photosynthetic photon flux density was 12.5 μmol m–2 s–1, with a 6 h photoperiod. Light colour (wavelength) had no significant effect on flowering date, or on the number of flowers collected (P < 0.05). Narcissus bulbs exposed to blue light (393 – 580 nm) formed shorter, more rigid shoots of lower weight with 13 – 40% shorter leaves.  相似文献   
56.

Purpose

The study aimed to characterise a fossil permafrost-affected (Stagnic Fluvisol Relictiturbic) soil, occurring in a cliff in the central part of the Polish Baltic coastal zone near Orzechowo (54° 35.664′ N, 16° 54.123′ E).

Materials and methods

The soil was sampled at 22 points and analysed using standard procedures in soil science. After standard preparation, disturbed and undisturbed soil samples were made subject to laboratory analyses concerning their physical and chemical properties. Radiocarbon dates and pollen analysis results were also obtained for the selected soil samples.

Results and discussion

The permafrost-affected soil lies beneath a fossil Dystric Histic Stagnosol, which is covered by about 8 m of aeolian deposits. The radiocarbon age of the Dystric Histic Stagnosol was 3061 ± 60 cal. years BP, and that of the Stagnic Fluvisol Relictiturbic 10,161 ± 110 cal. years BP. However, the results of pollen analysis suggest rejuvenation of the obtained dates. The Stagnic Fluvisol Relictiturbic developed in the marginal part of a body of water, from fluvioglacial and aeolian sands deposited on grey glacial till. The mineral substrates of the soil are moderately and poorly sorted sands and silt loam in the bottom part of the profile. This fine-textured material has been moved to the upper parts of the profile due to the impact of the water freezing and thawing cycles in the permafrost active layer. The observed microstructures on quartz grain (0.5–1.0 mm) surfaces, including conchoidal fractures, breakage blocks and v-shaped pits, are typical for periglacial soils. The fossil Stagnic Fluvisol Relictiturbic is poor in total iron. The observed vertical distribution of free iron oxides suggests their displacement in the permafrost active layer. Soil organic matter was found to be moderately or strongly humified, which is not typical for permafrost-affected soils and can suggest its allochthonous, probably alluvial, character.

Conclusions

The studied Stagnic Fluvisol Relictiturbic developed at the close of the Pleistocene in the marginal part of a body of water. It constitutes a sequence of horizons of varied thickness and abundance in organic matter. The influence of a periglacial environment is reflected in morphology of the soil (cryoturbations) and some chemical properties and partially in microstructures observed on quartz grain surfaces.
  相似文献   
57.

Purpose

The impacts of fly ash on the chemistry of forest floors were previously described in literature, while impacts on soil properties were less recognised. Soil investigations were focussed mainly on increases of pH and base saturations in surface horizons. The purpose of this study was to describe the influence of alkaline fly ash blown out from the dumping site of a lignite-fired power plant on pH changes of ectohumus horizons of Podzols and the morphology of deeper horizons.

Materials and methods

We investigated the soil profiles of Podzols derived from loose quartz sand and developed under pine forest surrounding the dumping site of the power plant Be?chatów, central Poland. In the vicinity of the fly ash dumping site, five Podzol profiles located at a distance of 50 m from the dumping site were investigated, as well as soil profiles located along the transect set at distances of 50, 300, 800 and 2000 m from the dumping site. Control profiles were located at a distance of 7.3 km from the dumping site. Soil morphology was described in the field and the following properties were determined: soil texture, hydrolytic acidity, exchangeable cations, total organic carbon and total nitrogen content.

Results and discussion

The pH values of Podzol ectohumus horizons located close to the dumping site ranged from 6.01 to 7.34 compared to a range of 3.08–3.72 in the control. Ectohumus horizon located 300 m from the dumping site showed a pH range of 4.13–4.26, while at a distance of 800 m, the pH values did not differ from those of the control site. The upper part of the eluvial soil horizons located close to the dumping site had been transformed into transitional AE horizons in which humic substances translocated from ectohumus horizons were accumulated. Moreover, the organic carbon content of this horizon increased compared to the carbon content of the illuvial Bs horizon located below it. Under the influence of alkalisation of upper horizons, the illuvial Bhs horizons vanished and were transformed into Bs horizons.

Conclusions

Changes in soils affected by fly ashes are connected with alkalinisation of ectohumus horizons. Podzolisation processes can be reduced or even completely stopped regarding the distance from the dumping site. Eluvial Podzol horizons located close to the dumping site may be transformed into AE horizons in which humic substances translocated from ectohumus horizons are accumulated. Due to transformation and translocation of organic components, Bhs horizons can be transformed into Bs horizons.
  相似文献   
58.
Polish garlic and white and red onions were subjected to blanching, boiling, frying, and microwaving for different periods of time, and then their bioactive compounds (polyphenols, flavonoids, flavanols, anthocyanins, tannins, and ascorbic acid) and antioxidant activities were determined. It was found that blanching and frying and then microwaving of garlic and onions did not decrease significantly the amounts of their bioactive compounds and the level of antioxidant activities ( P > 0.05). The HPLC profiles of free and soluble ester- and glycoside-bound phenolic acids showed that trans-hydroxycinnamic acids (caffeic, p-coumaric, ferulic, and sinapic) were as much as twice higher in garlic than in onions. Quercetin quantity was the highest in red onion among the studied vegetables. The electrophoretic separation of nonreduced garlic and onion proteins after boiling demonstrated their degradation in the range from 50 to 112 kDa.  相似文献   
59.
Potato spindle tuber viroid (PSTVd) was transmitted by Myzus persicae to Physalis floridana from P. floridana plants that also were infected with potato leafroll luteovirus (PLRV), whereas it was not transmitted by aphids from plants infected with PSTVd alone. Dot-blot hybridisation was used to detect PSTVd. The results indicate that PLRV can assist PSTVd in its transmission by M. persicae. Doubly infected, aphid-inoculated P. floridana plants from the previous experiment were used as the source plants in aphid transmission tests to the tomato cv. Rutgers, P. floridana and Datura stramonium. PSTVd was detected in 17 of 30 plants of tomato. The viroid was not detected by dot-blotting in any plant of P. floridana and D. stramonium in this experiment, but it was recovered from some plants by sap inoculation of the Rutgers plants. Treatment with RNase A of PLRV preparations purified from doubly infected plants indicated that PSTVd was encapsidated by PLRV particles.  相似文献   
60.
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