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Szkolkarstwo w swietle nowej dyrektywy

100%

Smaczynski K. , Haldas W.

Szkółkarstwo

2010

nr 3

75-78

In vitro culture of immature zygotic embryos of white clover [Trifolium repens L.]

100%

Haldas W. , Przywara L.

Acta Biologica Cracoviensia. Series Botanica

2002

tom 44

On the basis of EC6 medium, specific conditions were established to improve its properties as a nutrient medium for isolated, immature zygotic embryos of white clover. The highest frequency of embryo development occurred on medium with 117 mM sucrose concentration and 30% (v/v) coconut water for globular-stage (23.3%) and heart-stage embryos (78.3%). The development of globular-stage embryos was abnormal, however. The embryos callused after two weeks of culture. From the callus produced, plantlets and then plants were regenerated. A double-layer culture system, with the top layer having higher osmolarity than the bottom layer, enabled proembryos smaller than 60 µm to be cultured. For in ovulo embryo culture, Nitsch medium supplemented with 10% (v/v) cucumber juice proved most suitable. On this medium, approximately 13% of the ovules containing few-celled embryos germinated and produced seedlings.

In vitro culture of immature embryos of white clover [Trifolium repens L.]

100%

Haldas W. , Przywara L.

Acta Biologica Cracoviensia. Series Botanica. Supplement

1999

tom 41

nr 1

Influence of exogenous carbohydrates of superoxide dismutase activity in Trifolium repens L. explants cultured in vitro

80%

Slesak I. , Haldas W. , Slesak H.

Acta Biologica Cracoviensia. Series Botanica

2006

tom 48

nr 1

The effect of four sugars (sucrose, glucose, fructose, maltose) used as carbon source in liquid medium on superoxide dismutase (SOD) activity was studied. Little is known about how different soluble sugars used in plant tissue culture can affect SOD. an antioxidant enzyme involved in regulating the level of reactive oxygen species (ROS) in plant cells. In extracts of 15-day-old cotyledons and hypocotyls of Trifolium repens, four SOD forms were detected by native PAGE and activity staining: MnSOD, FeSOD, Cu/ZnSOD I and Cu/ZnSOD II. Activity of FeSOD and Cu/ZnSOD II was significantly lower in cotyledons cultured on media supplied with different carbohydrates than in control cotyledons cultured on medium without sugars, or was absent altogether. FeSOD was absent in hypocotyls obtained from seedlings grown on sterile filter paper (SFP); those cultured on sucrose-supplemented medium showed weak FeSOD activity. FeSOD appeared to be the most labile SOD form in T. repens cotyledons. MnSOD activity was highest in cotyledons cultured on sucrose-, fructose- and maltose-based media. Cu/ZnSOD I activity was highest in cotyledons cultured on medium with glucose and fructose. Sucrose strongly inhibited both FeSOD and Cu/ZnSOD II activity. The results indicated that various carbohydrates affect the activity of SOD forms in T. repens cotyledons. The decrease in activity of FeSOD and Cu/ZnSOD II, putatively located in chloroplasts, might suggest an inhibitory effect of some carbohydrates on photosynthesis in cotyledons of T. repens. On the other hand, supply of sucrose, fructose and maltose increased the activity of the putative mitochondrial form of MnSOD. This result might indicate sugar-induced production of ROS during respiration in mitochondria.