جستجوی مقالات مرتبط با کلیدواژه « Small seeds » در نشریات گروه « منابع طبیعی »

Pneumatic precision seeders are used for sowing of cereals. However, sowing small uncoated seed of medical plants is very difficult by these seeders. The purpose of this study was to investigate the performance of the pneumatic cylinder distributor to sow uncoated thyme seed and to determine its optimal conditions. The effects of four factors were investigated: the suction pressure at -6, -8, -10 kPa, the linear velocity of distributor at 3, 4, 5*10-2 m. s-1, the diameter of the distributor hole at 5, 7*10-4 m and the seed hole shape in conical and straightforward forms. In order to estimate the distributor yield, three indices of miss index, multiple index and quality of feed index for thyme were examined. The experiments were performed in 5 replications by the factorial method in a completely randomized design. The results showed that the suction pressure and linear speed of the distributor had a significant effect on the indices. The best performance of the distributor unit was obtained at -10 kPa pressure, 3*10-2 m. s-1 linear speed of the distributor, 7*10-4 m diameter for the distributor hole and the shape of the conical hole. Under these conditions, the values of miss, multiple and quality of feed indices resulted in 0.4%, 4.4%, and 95.2%, respectively.

Common cocklebur (Xanthium strumarium L.) is a widespread weed with high medical value and interested for researchers because of deep dormancy in one of its two seeds in one bur. However, lack of genomic data has led to low information about it. Transcriptome large and small seeds were sequenced using Illumina platform to identify and functional analysis of differentially expressed transcripts in two seeds. Identified sequences in each seeds were compared and differentially expressed genes were functionally annotated. In this research 191192 sequence with a mean of 989.69 bp were detected. Sequence similarity analysis and functional analysis was carried out aginst nr, GO and KEGG databases. Differentially expressed genes had the most similarity with sunflower (83.41 per cent) in terms of top hits. GO analysis led to identify 615 functional annotation distributed in 36 categories. The most abomdant GO in biological process was biosynthesis. Results of our research shows the higher biosynthetic and metabolic processes in large seed of certain bur rather than the small one and also key regulatory role of transcription during seed development.