Days Of Cold Stratification Research Articles

Efecto del árbol semillero y la época de cosecha de semillas en la capacidad germinativa en vivero de Fitzroya cupressoides

Identification of seed trees of Fitzroya cupressoides and seed collections were carried out in the Coastal Mountains of Valdivia. Germination tests ad plant production of F. cupressoides in nursery were tried with the seeds collected from different trees in different months. Results show great variability in number of seeds per kilogram and in seed viability, and a high percentage (47%) of trees with unviable seeds. To obtain good results in nursery plant production of Fitzroya cupressoides the following steps are recommended: 1. To identify good seed trees. 2. To determine the trees and months of high viability percentages through the cutting test. 3. To submit the seeds of marked trees located below 750 m of altitude to 60 days of cold stratification and 75 days to those above 750 m altitude. Germination capacities in the nursery varied between 0 and 37.5% for the different trees. Mortality after the first vegetative period reached an average of 17.35%.

Germination of embryos from stratified and non-stratified seeds and growth of apple seedlings (Malus domestica Borkh cv. "Antonówka")

The germination of whole seeds, the seeds without coat and isolated embryos of apple cv. "Antonówka Zwykła" after 90 days of cold-stratification was compared with the germination of embryos isolated from non-stratified seeds. They were germinated under 16hrs during a day at temperature 25°C and 20°C during the night. It has been found that after 2 weeks whole stratified seeds germinated in 5 per cent, seeds without coat in 25 per cent and isolated embryos in 98 per cent. Isolated embryos from nun-stratified seeds, after 2 weeks, germinated in the range from 75 to 88 per cent. The results indicate the similar germination ability of embryos isolated from nun-stratified seeds. The seedling populations obtained from embryo's stratified and non-stratified seeds were fully comparable and they evaluated: 1) a wide range of individual differences within population, 2) a similar number of seedlings in each class of shoot length, 3) a similar morphological habitus in each class of shoot length, 4) a similar fresh leaf weight and whole plant increment.

Electromagnetic Seed Treatment Increases Germination of Koelreuteria paniculata Laxm.1

Abstract Exposure of golden-rain tree seeds to an electromagnetic field of 100 gauss for 4.3 sec partially substitutes for cold stratification if applied after seed scarification. Germination was increased from 56 to 97%, when electromagnetic treatment was applied following scarification and before 84 days of cold stratification.