Growth and quality of Pinus nigra (Arn.), Pinus sylvestris (L.) and Pinus pinaster (Aiton) seedlings in two container types

Abstract

In this study we investigated the dynamics of growth and quality features of 1+0 Austrian Pine (AP; Pinus nigra Arn.), Scots Pine (SP; Pinus sylvestris L.) and Maritime Pine (MP; Pinus pinaster Aiton) seedlings in containers Yukosad (YS; hard plastic, 75cm 3 , 610 seedlings m-2) and Siset (SS; gray cardboard with white coating, 128 cm 3 , 589 seedlings m-2). The experiment, for all Pine species, was conducted in randomized blocks in four replications. Each replication contained 10 multipots of each container type. After the seed germination, every 15 days, i.e. 10 times during the vegetation season, 10 seedlings of each of 4 replications, i.e. 40 seedlings of each container and Pine species, were analyzed. The following morphological characteristics were measured: shoot height (SH), root collar diameter (RCD), shoot dry weight (SDW), number, length and dry weight (RDW) of I, II and III order lateral roots (FOLR, SOLR and TOLR) and of the central root. Quality ratios and indexes were calculated. The dynamics of growth of selected features during the vegetation season was expressed as trend lines. AP and SP seedlings, grown in containers YS had higher values of almost all measured traits (SH, RCD, SDW, number, length and dry weight of FOLR, SOLR and TOLR). However, in AP, the SS seedlings had better values of quality indexes and ratios (SQ, DQI, SDW/RDW and RDW/SDW ratio), than YS seedlings. SP seedlings, except for SQ, had better quality indexes in YS container. MP seedlings, with some exceptions, have better above ground quality features in SS containers, while root systems don't differ significantly in both containers. Root quality indicators (root intensity and root bound indexes) are more favorable in SS containers in all Pine species. The polynomial trend lines in AP and SP grow in similar way and intensity in both containers, gradually increasing during the vegetation season. MP seedlings differ in much more intensive growth of above ground features, especially in the half of the vegetative period in both containers, while during this period root quantity and length stagnates. Generally, the quality of AP and SP seedlings is more or less equal and satisfactory in both containers, while MP seedlings show slightly better results in SS container