The research was conducted with the aim of determining effects of seedling age on the yield of four fine rice varieties viz., Kalizura, Tulshimala, BRRI (Bang-ladesh Rice Research Institute)-37 and BRRI-38. The seedling of different ages such as 15, 25, 35 and 45 days were transplanted on the same day maintaining 25cm~times15cm spacing. The experiment was laid out in a randomized complete block design with three replications. The yield and yield contributing characters were influenced by seedling age, variety and their interaction. BRRI-38 gave the highest number of effective tillers hill-1 , panicle length, total spikelets panicle-1 , grains panicle-1 , 1000-grains weight and grain yield. Likewise, yield and yield contributing characters were the highest in 35 days old seedling. On the other hand, the variety (BRRI-38) with the same age as of seedlings 35 days old seedlings was found superior to other interactions, but, in the production of grains panicle-1 and 1000-grains weight there was no significant effect in this interaction. From the findings it may be inferred that BRRI-38 with 35 days old seedlings produced the highest grain yield.
Genetic diversity of 47 East-Asian vegetable soybean was characterized by means of agro-morphological traits and RAPD markers. A field trial was conducted to evaluate 14 agro-morphological traits. To study RAPD-based DNA analysis, a total of sixty 10-mer random primers were screened. Of these, 23 polymorphic markers in 16 varieties used for screening. Among 207 markers amplified, 48 were polymorphic for at least one pairwise comparison within the 47 varieties. A higher differentiation level between varieties was observed by using RAPD markers compared to morphological markers. Correspondence analysis using both types of marker showed that RAPD data could fully discriminate between all varieties, whereas morphological markers could not achieve a complete discrimination. Genetic distances between the varieties were estimated from simple matching coefficients, ranged from 0.0 to 0.640 with an average of 0.295~pm 0.131 for morphological traits and 0.042 to 0.625 with an average of 0.336~pm 0.099 for RAPD data, respectively. Cluster analysis based on genetic dissimilarity of these varieties gave rise to 4 distinct groups. The clustering results based on RAPDs did not match with those based on morphological traits. Geographical distribution of most varieties in each of the groups were not well defined. The results suggested that the level of genetic diversity within this group of East-Asian vegetable soybean varieties was sufficient for a breeding program and can be used to establish genetic relationships among them with unknown or unrelated pedigrees.