不同嫁接方式对海南省油茶高接换冠的影响

Impact of different crown grafting methodologies on survival and growth of Camellia oleifera in Hainan, China

为研发适宜海南省区域特色的油茶高接换冠技术,为油茶的采穗圃营建和低产林改造提供技术支撑,以海南省本地实生播种的8年生油茶树为砧木,研究不同嫁接方法、嫁接时期、砧木粗度、接穗品种、嫁接高度以及遮阴方式对油茶高接换冠的成活率及生长量的影响。结果表明:撕皮接、插皮接和改良拉皮接的油茶成活率分别为93.87%、90.55%和88.33%,插皮接的新枝生长量最大;在4月、8月和12月进行油茶嫁接,4月的嫁接成活率最高,同时枝条生长量也最大;嫁接部位砧木粗度以30~40 mm为宜,油茶的嫁接成活率和新梢生长量最大;选择不同品种的油茶穗条做接穗,其嫁接成活率和新梢生长量存在显著差异,嫁接成活率依次为‘海油4号’>‘海油2号’>‘海油1号’>‘海油3号’,枝梢生长量依次为‘海油4号’>‘海油3号’>‘海油1号’>‘海油2号’;砧木嫁接高度以距地60~80 cm为最佳,油茶成活率为92.78%,枝条生长好;嫁接后采用不同遮阴处理,70%遮光率的单层遮阳网处理效果最好,油茶成活率达96.11%。在海南省进行油茶高接换冠,最好选择在4月上旬接穗达半木质化程度时,选用直径大于20 mm的主枝作砧木,嫁接高度距地70 cm左右,嫁接方法选择插皮接,嫁接后用遮光率为70%的单层遮阳网遮阴,高接换冠效果好。

In this study,we studied crown grafting techniques in oil-seed camellias(Camellia oleifera)in the Hainan region of China.We explored the effects of grafting method,grafting period,rootstock thickness,scion variety,grafting height,and shading method on the survival rate and growth of eight-year-old C.oleifera trees.Survival rates varied according to the grafting method,with inlaying grafting,bark grafting,and improved bark grafting achieving 93.87%,90.55%,and 88.33%graft survival,respectively.Shoot growth in the bark grafting was highest.Grafts were carried out in April,August,and December,with grafts from the April treatment achieving the highest survival and best branch growth.Plants with a rootstock diameter of 30-40 mm had both the highest survival rate and growth rate of new shoots.The survival rate of grafts and the growth rate of new shoots differed according to which spike variety was selected as the scion.Ranked survival rates were‘Haiyou 4’>‘Haiyou 2’>‘Haiyou 1’>‘Haiyou 3’;growth ranking was‘Haiyou 4’>‘Haiyou 3’>‘Haiyou 1’>‘Haiyou 2’.Survival was highest(92.78%)and branch growth greatest when graft height was at 60-80 cm.The 70%shading treatment had the most positive effect on graft survival(96.11%).In summary,for crown grafts of C.oleifera stock,plants should be selected with a branch diameter of>20 mm,and one-year semi-lignified softwood twigs with leaves were selected as scions in early April;grafting height should be approximately 70 cm;and 70%shade should be provided for grafts.Modified crown grafting techniques have the potential to reduce graft mortality and increase growth,and ultimately to improve orchard efficiency and increase agricultural production in Hainan.