4种大型丛生竹笋竹生长规律研究

选择我国重要经济竹种龙竹、云南甜龙竹、版纳甜龙竹和黄金碧玉竹4种大型丛生竹种，研究了这些竹种的发笋情况、笋高生长规律以及施肥对竹笋生长的影响。结果显示：4个竹种的竹笋形态均呈锥形，笋体颜色深浅不一，个体大小不一，龙竹笋体最大，黄金碧玉竹笋体最小；在相同环境条件下，黄金碧玉竹退笋率最低（17%），其他依次为版纳甜龙竹（19%）、云南甜龙竹（22%）、龙竹（25%）；黄金碧玉竹的出笋期最长（222 d），其他依次为龙竹（170 d）、云南甜龙竹（153 d）、版纳甜龙竹（100 d）；4个竹种的竹笋生长均呈现出慢—快—慢的生长规律，各竹种竹笋出土后30 d内高生长缓慢，30~80 d高生长较快，80 d以后高生长趋缓直至停止生长；4个竹种的竹笋生长与降雨量密切相关，年降雨量大的地区，竹笋的各项生长指标均表现最好；施肥能明显降低退笋率，延长发笋期，增加笋直径；不同肥料种类对竹笋生长的影响不同，各竹种均表现为施用尿素的竹笋生长效果最好，其次为施用复合肥，施用过磷酸钙的效果不明显。

A Study of Growth Law of 4 Species of Sympodial Bamboo

Dendrocalamus giganteus Munro, D. brandisii (Munro) Kurz, D. hamiltonii Nees et Arn. ex Munro and Bambusa vulgaris var. striata Gamble were selected to study their shooting, shoot height growth law and the impact of fertilization on bamboo shoots. The results showed that the four bamboo species have the cone-shaped shoots with different shades of color and sizes, while D. giganteus Munro has the largest shoots and B. vulgaris var. striata Gamble has the smallest shoots. In the same environment condition, B. vulgaris var. striata Gamble has the lowest shoots degeneration rate, only 17%, which is lower respectively than D. hamiltonii Nees et Arn. ex Munro (19%), D. brandisii (Munro) Kurz (22%) and D. giganteus Munro (25%). B. vulgaris var. striata Gamble has the longest shooting period, 222d, which is followed by D. giganteus Munro (170 d), D. brandisii (Munro) Kurz (153 d) and D. hamiltonii Nees et Arn. ex Munro (100 d). The four species follow the "slow-fast-slow" growth law in their growth. They grow slowly in height within 30 d after shooting, grow fast in the later 30-80 d and become slow in growth to total cease after the 80^th day. The shoot growth of the 4 species of bamboo is closely related to rainfall, and when the annual rainfall is high, bamboo shoots grow the best in various growth indicators. The fertilization can obviously decrease the rate of bamboo degeneration, prolong the shooting period and increase the shoot diameter. The fertilizer formula has different impact on shoot growth. The application of urea ensures the best shoot growth, followed by compound fertilizer and superphosphate which has the minimal effect on shoot growth.