不同促脂剂对湿地松家系的增脂效果及对生长的影响

Effects of Different Resin-Stimulant Pastes on Resin Production and Growth of Pinus elliottii Families

【目的】明确不同成分促脂剂对湿地松的促脂效果以及对生长量的影响,筛选出适宜广东地区湿地松的促脂剂,为实际生产中降低采脂成本提供参考。【方法】以广东省台山市红岭种子园的湿地松半同胞子代测定林为研究对象,分别进行不割脂(T0,生长量对照)、常规割脂(T1,试验对照)和使用不同成分促脂剂T2~T5割脂,促脂剂的主成分分别为K2SO4、萘乙酸(NAA)、苯甲酸(BA)和乙烯利(CEPA)。2018年处理并收集松脂7次,2019年处理并收集松脂6次,在处理前收集1次不使用促脂剂的本底产量,所有产脂量和生长量均进行每木测量。【结果】2018年分析结果显示,家系效应和处理效应都极显著(P<0.01),二者互作效应不显著(P>0.05)。前2次促脂效果极显著,增脂率超过135%,而第3次促脂效果有所下降,到第4次时只有T5的脂产量高于对照,但也未达到显著水平,第5~7次T2-T4均没有显著的促脂效果,仅T5依旧保持19%以上的增脂率。7次收集总脂产量显示T5促脂效果最好,增脂率为51.73%。2019年分析结果显示,家系效应在第1次收集不显著(P>0.05),在其他批次都是显著或极显著水平(P<0.05),各个处理组的产脂量本底值无显著差异,之后6次均显示出显著的促脂效果,增脂率29%~269%。6次收集总产量显示,T5促脂效果最好,增脂率为160.61%。各家系产脂量的排名在不同年份、不同处理间变化较大,其中家系I2和I7相对较稳定。2年的生长量分析结果表示湿地松家系效应显著,不同处理组之间的生长量无显著差异,不同处理组之间树高和0.9 m的直径在1年内的增量也没有显著差异。同一年份内不同批次的产脂量有极显著的相关性,相关系数范围0.245 5~0.854 4;不同批次与总产量的相关系数,2个年份均是第1次割脂与总产量的相关系数最低。产脂量与生长量的相关性分析结果显示,产脂量与0.9 m高处的直径有较稳定的极显著正相关,而产脂量与树高的正相关性不确定,在不同年份以及不同的处理中不显著、显著或极显著水平均有检测到,2018年还检测到1次显著的负相关。【结论】不同成分的促脂剂对湿地松的增脂效果差异显著,同一促脂剂在不同气候环境条件下效果也不同,本研究显示以20%硫酸与3%CEPA为主要成分的T5促脂效果最好也最稳定,且与家系无显著互作效应,适宜在湿地松林中大面积推广使用。同一株树在不同时间产脂量差异较大,在测量产脂量性状时,应避免只用第1次割脂的数据。不同家系在不同时间、不同年份和不同处理的产脂量也有较大变化。参试的11个家系中I2和I7的产脂量相对较高且较稳定。使用促脂剂在短时间内对树木高度和0.9 m高处的直径生长均无显著影响,产脂量与直径的相关性较强,在一定程度上可以使用直径作为产脂量的间接选择性状指标。虽然产脂量与树高相关性较弱,但使用T2、T3、T5促脂剂对较高树高的湿地松增脂效果更加显著。

【Objective】This study aims to clarify the effect of the different kinds of resin-stimulant pastes on resin production and growth of Pinus elliottii, and to screen out the resin-stimulant paste suitable for P. elliottii in Guangdong, so as to guide actual production and reduce the cost of resin tapping.【Method】This study was conducted in the half-sib progeny test forest of P. elliottii in Hongling Seed Orchard, Taishan, Guangdong. Six treatments were set, and they were non-tapping(T0, for growth control), conventional tapping without any resin-stimulant paste treatment(T1, for experimental control), and tapping treated with different components of resin-stimulant pastes(T2-T5). The main components of the pastes were K2SO4, naphthalene acetic acid(NAA), benzoic acid(BA) and 2-chloroethylphosphonic acid(CEPA), respectively. In 2018, the trees were treated and harvested seven times, and in 2019, they were treated and harvested six times. Before the treatment, the basic value of resin yield was harvested without resin-stimulant pastes. The resin yield and growth trait were all measured per tree.【Result】The result in 2018 showed that the effects of both family and resin-stimulant paste treatment were extremely significant(P<0.01), however their interaction effects were not significant(P>0.05). The first two collections showed that the resin stimulating effect was extremely significant, with the resin increase rate over 135%. However, resin stimulating effect decreased in the third collection. By the fourth time, only T5 treatment group had a stimulating effect, but it did not reach a significant level. From the fifth to seventh times, T2-T4 treatment group did not have a significant stimulating effect, but T5 treatment still maintained the resin increase rate of more than 19%. The total yield of resin for seven collections showed that T5 treatment group had the best resin stimulating effect, with a resin increase rate of 51.73%. The result in 2019 showed that the family effect was not significant in the first collection(P>0.05), while the family effect in the other collections was extremely significant(P<0.01). The background value of the resin yield in each treatment group showed no significant difference, and then the following six collections showed significant resin stimulating effect, with the resin increase rate ranging from 29% to 269%. The total of the resin yield for six collections showed that T5 treatment had the best resin stimulating effect, with a resin increase rate of 160.61%. The ranking of resin production of each family varied greatly in different years and different treatments, and among them family I2 and I7 were relatively stable. The result of the two-year growth showed that the family effect was significant, however there was no significant difference in the growth among the different treatment groups, and there was no significant difference in the one-year increment of tree height and diameter at 0.9 m height among different treatment groups. The resin production of different collections in the same year had an extremely significant correlation. The correlation coefficient ranged from 0.245 5 to 0.854 4. In the two years, the first harvest of resin production had the lowest correlation coefficient with the total production. The correlation analysis between the resin production and growth showed that there was a stable extremely significant and positive correlation between resin production and diameter at 0.9 m height, however the correlations between resin production and height growth showed no significant, significant, or extremely significant levels in different periods of time and with different treatments. A significant negative correlation was even detected between resin production and height in 2018.【Conclusion】The resin-stimulants with different components have significantly different effects on the resin increasing of P. elliottii. The same resin-stimulant pastes have different resin increasing effects under different climatic conditions. This study shows that T5, with 20% sulfuric acid and 3% CEPA as the main components, has the best and most stable resin stimulating effect, and has no significant interaction with the family. Thus, T5 is suitable for popularization in P. elliottii forests. The resin yield of the same tree varies greatly at different harvests. When measuring resin yield traits, it should be avoided to only use the data of the first resin tapping. The resin production of different families also changes greatly in different harvests, different years, and different treatments. Among the 11 families tested, the resin productions of families I2 and I7 are relatively high and stable. The use of resin-stimulant pastes has no significant effect on the growth of tree height and diameter at 0.9 m height in a short period of time. There is a strong correlation between resin production and tree diameter. To a certain extent, tree diameter could be used as an indirect selective indicator of resin production. Although the correlation between resin production and tree height is weak, the resin-stimulant effect of P. elliottii with higher tree height is more significant when the T2, T3 and T4 resin-stimulant pastes are applied.