Emergence and development of seedlings of safflower depending on seed size

Abstract

The seed size can influence the seedlings emergency and vigor. It was evaluated the emergency and the development of safflower in function of the seed size. The classification was obtained using sieves with round role with diameters of 3.18; 3.57; 3.97 and 4.36 mm. It was made the weighting to observe the proportion of each seed size in the lot. To each size class were determined the 1000-seeds weight and the water content. It was used a completely randomized design with five treatments and four replication with 30 seeds each one. The variables analyzed were the percentage, the speed index and the average time of emergency. The counting were made daily until the 10^th day after the seeding. The water content kept the same and the 1.000-seeds weight grew-up with the seed size. It was evaluated the dry matter of the aerial part and the height of the seedlings. It was observed that the water content kept constant with the variation of the seed size. The 1.000-seeds weight grew-up proportionally according to the seed size. The seeds kept in the sieve with diameter equal to 3.18 mm present the smallest proportion in the lot, while those seeds kept in the sieve with diameter equal to 3.97 mm have the highest representativeness in the lot. The seed size does not interfere on the physiologic quality and vigor of safflower seedlings.