Evaluation of seed moisture content at harvest time on seed quality, germination and vigor of Rape seed (Brassica napus L.)

In order to evaluation of most suitable seed moisture content at harvest for production of high viability and vigor seed of two Oil-seed rape cultivars، this study was conducted during 2000- 2009 in Dezfoul. Therefore samples of Hyola 401 and Hyola 308 cultivars seeds by 10%، 15%، 25% and 35% moisture content harvest from seed multiplying field and at central seed analysis laboratory of Seed & Plant Certification & Registration Institute (SPCRI) in Karaj by conducting standard germination test، some seed quality indices like as primary and final germination percent (seed viability)، normal and abnormal seedling number، mean daily germination speed (MDG)، daily germination speed (DGS)، seedling length، fresh and dry seedling weight and seedling vigor index (seedling dry weight × viability) measured. Obtained data by 2×4 factorial experimental based on completely randomized design with three replication، combine analyzed and results revealed that expect of normal and abnormal seedling number، all measured indices affected by studied factors and primary and final germination percent، mean daily germination speed (MDG)، fresh and dry seedling weight and seedling vigor index (seedling dry weight × viability) affected by cultivar × seed moisture content × year interaction. Highest primary and final germination percent obtained at 15 percent seed moisture content for both cultivars. Also the highest rate of mean daily germination speed (MDG)، fresh and dry seedling weight and seedling vigor index (seedling dry weight × viability) obtained at 15 percent seed moisture content for both cultivars. In addition to، primary and final germination percent of Hyola 401 was more than Hyola 308. This result revealed that seed quality and its various aspects affected by environmental factors and seeds harvested at 15 percent moisture content have highest seed quality.