轻基质配比对3种珍贵树种2年生容器苗生长及氮和磷吸收的影响

Substrate proportion for growth and N/P absorption in two-year-old container seedlings of three precious tree species

以浙江楠Phoebe chekiangensis,浙江樟Cinnamomum chekiangense和南方红豆杉Taxus wallichiana var.mairei2年生容器苗为材料,研究轻基质配比对其生长、根系发育及氮、磷吸收的影响,共设置2种体积分数基质配比,分别为45%泥炭+40%谷壳+15%黄心土(S1)和35%泥炭+40%谷壳+25%黄心土(S2)。结果表明:浙江楠在S1基质下,其苗高和茎生物量分别达88.91 cm和23.35 g,明显优于S2基质,分别较其高6.61 cm和3.39 g。浙江樟和南方红豆杉高生长则均表现为S2基质显著优于S1基质,浙江樟地径、茎生物量和南方红豆杉单株生物量在S2基质下分别为9.08 mm,9.21 g和29.70 g,分别较S1基质下大11.5%,27.2%和22.7%。南方红豆杉根系发育受基质配比影响显著,S2基质下其根长、根表面积、根体积及根直径均比S1基质下大34.5%以上;浙江楠和浙江樟在2种基质间根系发育差异不显著。基质配比显著影响浙江樟和南方红豆杉氮和磷吸收,S2基质下,2个树种氮和磷分别为489.66,26.86 mg和559.13,42.81 mg,均显著高于S1基质;浙江楠氮和磷吸收在2种基质间差异不显著。结合生长和养分吸收状况,浙江楠较适宜于泥炭比例相对较高(体积分数为45%),黄心土比例较低(15%)的S1基质,浙江樟和南方红豆杉则在泥炭比例较低(35%),黄心土比例较高(25%)的S2基质下生长较好。可见,不同珍贵树种容器苗对基质配比要求不同,为提高容器苗质量应依据树种特性调整基质成分的比例。

To analyze the effect of different substrates（S） on growth as well as nitrogen（N） and phosphorus（P） status in the three kinds of trees, two-year-old container seedlings of Phoebe chekiangensis, Cinnamomum chekiangense, and Taxus wallichiana var. mairei were used as the objective material. The seedlings were cultured in substrates S1（45% peat, 40% rice husk and 15% mud） and S2（35% peat, 40% rice husk and 25%mud） with single factor randomized block design. Three replications for them were carried for each treatments.And their growth data for the two treatments were tested by T test analysis in SPSS 18.0. Results showed that P. chekiangensis cultivated with S1 grew better than S2 with height of 88.91 cm（6.61 cm larger than S2）（P=0.034） and stem biomass of 23.35 g（3.39 g larger than S2）（P =0.020）. Compared to S1, growth of C.chekiangense and T. wallichiana var. mairei cultivated with S2 was better with diameter at ground 1.3 m of9.08 mm（larger by 11.5%）（P=0.020） and stem biomass of 9.21 g（larger by 27.2%）（P=0.040） for C.chekiangense; whereas, for T. wallichiana var. mairei, biomass was 29.70 g（larger by 22.7%）（P=0.010）. The effect of S2 on root length（P=0.010）, root surface area（P=0.002）, root diameter（P=0.001）, and root volume（P〈0.01） for T. wallichiana var. mairei was larger than S1 by more than 34.5% for each factor. With S2 the N（489.66 mg）（P =0.001） and P（26.86 mg）（P =0.001） content of C. chekiangense, and the N（559.13 mg）（P〈0.001） and P（42.81 mg）（P〈0.001） of T. wallichiana var. mairei were higher than that of S1. However,nutrition absorption of P. chekiangensis did not display differences between the substrates. So, for large container seedlings of these three precious trees, according to both growth and nutrition absorption results, P.chekiangensis would grow better cultivated with S1 which contains more peat and less mud; whereas, C.chekiangense and T. wallichiana var. mairei should be planted with S2 which contains less peat and more mud thereby taking into account the special characteristics of each tree.