甘薯是一种无性繁殖的高产作物。但繁殖倍数低,用种量大,因此,生产上靠调种或买苗面导致混杂、退化,病害蔓延。甘薯优种高倍繁种法,能够节省瓜种,加快繁种速度,便于提纯复壮,消灭病杂和退化现象,是一项繁育甘薯良种的新技术。甘薯优种高倍繁种法主要特点是优、大、高、密。优是指选优种株,即在病、杂、退化的生产地中选择种性好,生长健壮的一个优良单株,或从新推广的品种中,选一优良单株作原种,大是指大株育苗,将选出的原种采用火炕早期育苗法,育出壮苗,然后将秧头育成大株薯,从大株薯培育壮苗;高是指高倍繁殖,从大株薯的秧苗上剪单叶节或双叶节壮苗在良种田中插植,也可用摘顶的方法促使薯苗分杈,扩大繁殖系数;密是指通过密植繁殖种薯,从大株薯上和苗圃中剪短壮苗以适当的密度进行栽培。具体方法如下: Sweet potato is a clonal high-yield crop. However, the multiplication ratio is low, with a large amount of seed, therefore, production by planting or buying seedlings leading to miscellaneous, degradation, disease spread. It is a new technology to breed sweet potato breeds. It can save melon seeds, speed up breeding, facilitate purification and rejuvenation, eliminate diseases and degeneration. The main characteristics of high-yielding sweet potato variety is excellent, big, high and dense. Excellent refers to the selection of superior strains, that is, in the disease, miscellaneous, degraded production in the selection of good sex, robust growth of a fine single plant, or from the newly promoted varieties, choose a good single plant as a species, is Refers to the large plant nursery stock, the selected original species used kang kang early nursery law, nurturing strong seedlings, and then Yangguo into a large plant potato, cultivating strong seedlings from large potatoes; high refers to the high multiplication, from the big potato Saplings cut on leaflets or bilu section strong seedlings planted in good farming, but also can be used to pick the top method to promote seedlings bifurcation, expansion of breeding coefficient; dense refers to the close planting of seed, from the big potato and nursery Short sturdy seedlings are planted at the appropriate density. Specific methods are as follows: