Studies On The Techniques Of Containerizd Nusery Of Melia Azedarach And Pterocarya Stenoptera

Four aspects of the techniques of containerized nursery, including container size, growing medium, root control and seedling density, were systematically studied for Melia azedarach and Pterocarya stenoptera, which are two native afforestation and reforestation species in Jiangsu province.Based on the determination of seedling height, caliper, capital root length, number of﹥5cm lateral root as well as seedling biomass and analysis of some physiological indexes,the seedling growth rhythm of two species were revealed and the suitable container size, growing medium,root control techniques and seedling density were determined. As a result, the basic techniques for containerized nursery of M.azedarach and P. stenoptera. could be provided and these techniques could be a technical support for industrialized seedling production of the two species.The experiments were done at a demonstration nursery in Niushou forest farm of Nanjing, Jiangsu province from March to November in 2006.The main results were shown as follows: 1. The plastic bags of five different sizes (6cm×6cm×12cm , 8cm×8cm×12cm ,8cm×8cm×16cm,10cm×10cm×12cm,10cm×10cm×16cm) were used for growing seedlings in order to select the most suitable container size. After an overall study, it was found that the best size of container for growing above two species was 8cm×8cm×16cm.As the seedling quality in this size of containers was the best both in morphological and physiological indexes.2. Six kinds of growing media, including loess, peat,loess:peat (3:2), loess:peat:perlite (1:1:0.2), loess: sawdust: perlite (2:1:0.1), loess: turf: perlite (1:1:0.2) were used for growing seedlings to compare their effect on seedling quality. It was found that formula 5 and formula 6 were the best media for growing seedlings of M .azedarach and formula 6 was the best medium for P. stenoptera, followed by formula 4 and formula 5. It was also indicated that half-light medium was more suitable for growing containerized seedlings.3. The root-control methods of air pruning and chemical pruning were used to improve the root quality of containerized seedling of the two species.The results of experiments showed that the air pruning was very effective for root-control, because the root conglobation was obvious, and the numbers of lateral root as well as root vigor were significantly different from other treatments.For chemical pruning, the carbonate cuprum concentration of 100-200 g·L-1 was the best for M. azedarach and 150g·L-1for P. stenoptera.4. Three different densities (100 bags/m2, 64 bags/m2, 36 bags/m2) were designed to study the effect of density on the quality of containerized seedling.The results showed that the seedling uniformity and quality were significantly affected by seedling density.And the seedlings at the density of 64 bags/m2 grew best on the whole and were most suitable for afforestation.