When etiolated soybean seedlings are treated with the synthetic auxin, 2,4-dichlorophenoxy-acetic acid, cells of the mature hypocotyl become swollen and proliferate abnormally. This abnormal growth induced by auxin coincides with a 5- to 8-fold increase in the alpha-amanitin-insensitive RNA polymerase associated with isolated chromatin or nuclei. The alpha-amanitin-sensitive RNA polymerase acti...

Experiment on estimation of qualitative changes in populations of meadow fescue (Festuca pratensis Huds.) after seed storage in different conditions were taken. Phenotypical traits for plants derived from seeds stored during 54 months in two different kind of storage conditions were compared. Storage of meadow fescue seed during 54 months in unfavourable conditions resulted in decrease of initi...

Maintenance of organ separation is one of the essential phenomena for normal plant development. We have identified and analyzed ONION3 (ONI3), which is required for avoiding organ fusions in rice. Loss-of-function mutations of ONI3, which were identified as mutants with ectopic expression of KNOX genes in leaves and morphologically resembling KNOX overexpressors, showed abnormal organ fusions i...

The Arabidopsis mutants eto1 (ethylene overproducer) and eto3 produce elevated levels of ethylene as etiolated seedlings. Ethylene production in these seedlings peaks at 60 to 96 h, and then declines back to almost wild-type levels. Ethylene overproduction in eto1 and eto3 is limited mainly to etiolated seedlings; light-grown seedlings and various adult tissues produce close to wild-type amount...

Seedlings of Leptospermum scoparium J.R. et G. Forst (manuka) originating from seed from a low altitude coastal site (Auckland) and from a high altitude inland site (Desert Road) were grown for 96 days in four controlled environments to compare the relationship between growth temperature and frost hardening. Day/night temperature treatments were 12/6, 12/3, 12/0 and 12/-3 degrees C. Frost hardi...

The chloroplast is the most prominent and metabolically active plastid in photosynthetic plants. Chloroplasts differentiate from proplastids in the plant meristem. Plant plastids contain multiple copies of a small circular genome. The numbers of chloroplasts per mesophyll cell and of plastid genome copies are affected by developmental stage and environmental signals. We compared chloroplast str...

      Dust storms are increasingly threatening the forest ecosystem in Western Iran. Due to its coverage of vast area of Zagros forest, the Quercus brantii is at the front line of the attack. Most tree deaths in this forest are from this species. This study aims to investigate the effect of simulated dust on wood development and leaf stomata from seedlings of Persian oak. The oak seedlings were...

A bstract. Kinetin in concentrations of 10-e to 10-4 M, stimuated ethylene production in 3 and 4-day old etiolated seedlings of Alaska pea (Pisucm sativum L. var. Ala-ka). Seedlings of other species responded similarly. The response to kinetin depended on the age of the seedlings. Kinetin alone did not influence ethylene production in 6-day old stem sections, but it greatly increased the enhanc...

Vast areas of land will require reclamation and reforestation following oil sands development in northeastern Alberta. Greenhouse-grown tree and shrub seedlings used in reforestation may be clipped or girdled by meadow voles, especially during periods of high population density. The impact of partial girdling, the most common form of damage, varies among species. Reduced survival rates in seedl...

A study was conducted in 2010 to investigate the effects of crude oil contaminated soil on biomass accumulation inJatropha curcas seedlings in Asaba, Delta State, Nigeria. Oil levels used were 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0% w/w. The trial was arranged in a randomized complete block design with four replications and monitored for 12 weeks after transplanting. Results showed that contamination...