Research On Substrates Effects Of Sowing And Seedilings Growth Of Podocarpus Nagi

In this paper, the experimental field is in the breeding base of Wuyishan gold Podocarpus Nagi Co. Ltd. On one hand, in order to study the effects of different substrates and fertilization on seed germination rate and seedling growth of Podocarpus Nagi, A, B, C 3 kinds of seedling substrate are chosen, substrate A is the soil in the breeding base, substrate B is called light matrix which is composed of fir bark, semi carbonized chaff, peat soil, slow release fertilizer and Soil disinfectant, substrate C is 1:1 mixed substrate of soil and light matrix. Substrate A and B are the most commonly used substrates in the company. The study found that the seeding emergence rate and the seedling growth of Podocarpus Nagi are significantly influenced by different substrates. On the other hand, in order to study the effect of different substrates and formula of N, P, K mixed fertilizer on seedling growth and physiological and biochemical indexes, the seedlings of 70-80 days are taken for the objects. The study found that the composite effect of N, P, K on the growth and physiological and biochemical indexes of Podocarpus Nagi seedlings are significantly, but the effects of single factor is not obvious. The results provide theoretical and technical support for breeding selection and seedling management of Podocarpus Nagi in the future. The followings are the main conclusions:(1) The sowing of Podocarpus Nagi of the experiment is in mid-March, in late March began to emerge. The emergence peak came in May and June. Seeding emergence rate difference of A, B, C three kinds of seedling substrate reached significant level. The highest germination rate appeared in substrate C, up to 81.65%, followed substrate B, the rate is 80.33%, substrate A had the lowest rate of 74.28%.(2) Effects on seedlings growth of 3 kinds of substrates reached significant level. In substrateB the height growth of Podocarpus Nagi seedlings reached 9.21cm, much better than Podocarpus Nagi seedlings in substrate A and C. It showed that substrate B is more suitable for the height growth of Podocarpus Nagi seedlings. In substrate A, average ground diameter of Podocarpus Nagi seedlings is the largest, reaching 3.762mm. It showed that soil is beneficial to ground diameter growth of Podocarpus Nagi seedlings.(3) In different months, the height growth of Podocarpus Nagi seedlings had large differences. In September and October, the seedling height grew fastly. In July and August, the growth was slowly. The growth was significantly decreased when it comes to November. The main reason is the temperature in July and August are high, and the temperature is low in November because of winter comes. The growth peak of ground diameter is the same as height, but the decline ratio is lower than height. Podocarpus Nagi seedlings growth is affected by temperature effect, high or low temperatures are not conducive to the growth of the seedlings.(4) Effect of substrate B on the chlorophyll content, POD activity, soluble protein content, soluble sugar content was the maximum. The maximum value of the corresponding index were appeared in August, September, October, November, respectively 1.78mg·g-1、2.23u·mg-1、46.31 mg·g-1、30.59 mg·g-1. The maximum value of SOD activity appeared in September of substrate C of Podocarpus Nagi seedlings, is 1.14 u·mg-1. That means light matrix is helpful to improve the chlorophyll content, POD activity, soluble protein content, soluble sugar content, more benefical to the growth of Podocarpus Nagi seedlings.(5) Podocarpus Nagi seedlingsmixed treated with Substrate, N, P, K is good than in the control without fertilization Podocarpus Nagi seedling. In the same substrate, N, P, K single factor effect was not significantly different, N, P, K factor combined effect was significant. In a certain range, the raise of fertilization level contributed to a better growth of Podocarpus Nagi seedlings, all biochemical and physiological indexes improved. The maximum value of the main growth indexes and physiological indexes were found in the B matrix of Podocarpus Nagi seedlings except ground diameter and SOD activity. Formula N3P1K3 in substrate B had the highest average seedling height 9.38cm. It means formula N3P1K3 in substrate B is helpful to the growth of Podocarpus Nagi seedlings.