| Abstract: | Summary Factors limiting growth in media culture are oxygen, nutrients and water. These factors are dependent on particle diameter, nutrient solution composition, and irrigation frequency. This study evaluated combinations of trickle irrigation frequencies and particle sizes of media on the growth ofChrysanthemum morifolium Ramat. irrigated with a complete nutrient solution. Plant height, fresh weight, dry weight, and flower diameter were used to measure growth. Media used were: coarse incinerated anthracite refuse, fine incinerated anthracite refuse, and soil material from the B21 horizon of Gatesburg sand. Irrigation frequencies were: once per day, four times per day at 4-h. intervals, and constantly during the 13 daylight hours. Fine incinerated anthracite refuse irrigated constantly and every 4 hours produced chrysanthemums with significantly greater height, fresh weight and flower diameter than other treatments, whereas Gatesburg sand irrigated daily resulted in less growth than other treatments. Excess water held in finer textured media causes oxygen deficiency and substandard growth. Authorized for publication November 5, 1973 as paper no.4561 of the Journal series of the Pennsylvania Agr. Exp. Sta., University Park, Pa. 16802. The authors gratefully acknowledge support from The United States Agency for International Development (U.S.A.I.D.), through a 211 (d) grant to the Agronomy Department at The Pennsylvania State University. The information and conclusions in this paper do not necessarily reflect the position of AID or the U.S. Government. Research Assistant, Associate Professor of Floriculture, Associate Professor of Soil Genesis and Morphology, and Associate Professor of International Agronomy, respectively. |
