| Abstract: | Different ploidy ramie materials were studied via microscopic observation on stem sections andmacerated fiber cells. Morphologic differences between different ploidy plants were analyzed. Average barkarea percentages in ramie stem transection of hapioids, tetraploids, diploids and triploids were 28.91, 27. 05,26.97 and 24.77 % respectively. Average percentages of fiber layer area of diploids, haploids, tetraploids andtriploids were 16.80, 16.58, 15.52 and 13.78% respectively. Average fiber cell diameter and cell wall thick-ness were increased along with the increase of the ploidy of the plants. Average fiber length of diploids, trip-loids and haploids were 8.49, 7. 96 and 6.93 em respectively. Average L/B (length/breadth) of diploids,triploids and haploids were 2 470.7, 2 390.6 and 1 616.3 respectively. Average breadths of fiber of haploids,diploids and triploids were 29.30, 33. 87 and 49. 20 μm respectively. However, there were relatively largevariations in the above characteristics among the ramie materials of the same ploidy levels. Field performanceof different ploidy plants was also investigated. As the chromosome ploidy increasing, there was a tendency ofdeclining in shoot number per plant and increasing in stem diameter. Average shoots per plant of haploids,diploids, triploids and tetrapioids were 5.83, 5.30, 3.77 and 3.65 whereas their average stem diameters were0.66, 0.67, 0. 74 and 0. 76 cm respectively. Triploids were the tallest, while haploids were the shortest.Triploids had strong growth vigour, diploids and tetraploids had moderate growth vigour, while haploids ap-peared to be lack of growth vigour. Cold stress tolerance of tetraploids were the strongest, diploid had themoderate tolerance, while haploids and triploids were the least tolerant to cold stress. Both haploids and trip-loids were sterile. |
