Sowing times affect flowering, pollen viability and seed yield of Zinnia elegans cvs. ‘Lilliput’ and ‘Super Yoga

A study was conducted to evaluate the influence of various sowing times on flowering, pollen viability and seed yield of zinnia (Zinnia elegans) cultivars ‘Lilliput᾿ and ‘Super Yoga᾿ under Faisalabad, Pakistan conditions. Seeds of both Zinnia cultivars were sown in 128-cell plug trays at 20 days interval from March 14 to August 20, during 2019. Seedlings were transplanted in thoroughly prepared field beds after 15 days of each sowing, according to factorial arranged randomized complete block design, with three replications. Data were recorded for various growths, flowering traits, pollen viability and seed related parameters. Super Yoga excelled over Lilliput for most the studied traits except number of lateral shoots, flowers per plant, unopened flower buds, pollen viability and seed yield per plant; values of these traits were higher for Lilliput than Super Yoga. Significant variation among various sowing times was recorded in both cultivars. Seeds sown on March 14, 2019 performed best compared to later sowing times for plant height, number of lateral shoots per plant, length of the lateral shoots, leaf area, number of flowers per plant, flower diameter, pollen viability, seed yield per plant and seed viability. However, total number of un-opened flower buds, seed weight per flower and 100-seed weight were more in April 03 sowing, although statistically similar to March 14 sowing. Seed yield declined gradually with delay in sowing; 66% less seed yield in June 20 sowing. Further delay in sowing did not produce seed. It was concluded that Zinnia should be sown by mid-March for getting high seed yield of good quality; later sowing, even during first week of April, resulted in 17.5% decrease in seed yield.