Study On The Supplemental Lighting System Of Six Species Of Genus Abies

In this article, an introduced species, white fir (Abies concolor) was used as the material to study the supplemental lighting system, in order to get the easiest popularized light source, suitable light intensity and light duration (photoperiod). Then we investigated the correlative physiological changes and try to explain the mechanism of the fast growth of the fir seedlings under supplemental light at night. Then we use this lighting system to grow six species of true firs (one is ck) to compare their seedling stage traits and variations, selecting the most responsive fir species, provenances and families. The results are as follows:(1) The dysprosium lamp, light intensity 12 μ mol·m-2 ·s-1 and 22h photoperiod were selected for the most suitable supplemental lighting system. It reduced the breeding cycle 1.5-2.5 years compared to the normal breeding method.(2) As for the chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and starch content and POD activity, the seedlings under supplemental light were lower than the ck., while the ratio of chlorophyll a/b were the reverse. The plant hormones such as endogenous IAA, ABA and soluble protein content hadn't varied regularly during investigation. It's the combination effect of light's direct and indirect effect that promoted the seedlings growth under supplemental light.(3) Under the supplemental lighting system of the greenhouse, grand fir and white fir were the most responsive and fast-growing species. The shoot length of the six species varied greatly. The highest was grand fir, which reached 19.86cm. As an elementary conclusion, the provenance 8871100 of grand fir, provenance 12, families 524-2, 524-9, 534-7 of white fir were selected for the fastest shoot growth. The sequence of root collar diameter was the same with the shoot length. The largest root collar diameters of white fir were family 524-6 and 534-7, while the smallest were family 524-2 and 534-1. The grand fir had the most lateral branch, which reached 9.12. The variation coefficient of the number of lateral branch in sequence was Grand fir>White fir > Pacific silver fir> Subalpine fir> Balsam fir>ck.