【摘要】 优质种苗是梨果生产的基础,我国梨种苗繁育多采用砧木实生苗嫁接,常规育苗模式是"春季砧木露地播种、不断根不移栽、翌年秋季出圃"的2年生长周期,存在着主根发达侧根少、苗木整齐度差等苗木质量问题。为提高育苗质量,以杜梨为砧木,秋月、新梨7号和玉露香为接穗品种,研究春季露地播种时间、断根苗的栽植密度和断根处理对苗木生长的影响,创建了新的壮根育苗模式。结果表明:杜梨春季播种提早20 d,秋季成苗的株高与茎粗均比常规播种提高30%以上;断根苗的栽植密度以株距15cm、宽窄双行栽植效果好;春季移栽前断根处理,嫁接苗的侧根数、根尖数、根总长度和根体积均显著高于不断根处理的苗木,分别提高了4.30、2.59、0.98、1.34倍;秋月、新梨7号和玉露香3个梨品种在壮根育苗模式下的株高生长量分别较常规育苗模式增加了21.44、39.10、26.97cm,茎粗生长量分别增加了1.99、2.86、3.22mm;嫁接苗一级苗率均在80%以上。综上所述,采用"提早播种+断根+控密度移栽"的壮根育苗模式,优质苗率高、苗木整齐度好。更多还原

【Abstract】 High-quality nursery stocks are basis for high fruit production of pears(Pyrus spp.). The nursery stocks of pears are usually propagated by grafting on seedling rootstocks in China. The conventional propagation mode is a two-years growth cycle: seeds of rootstocks are sown in field in spring; grafted seedlings come out of the nursery in next autumn without pruned roots treatment and transplanting. However, there are exsiting problems such as nursery plants with few lateral roots and poor uniformity. In order to tackle these problems, Pyrus betulifolia were used as rootstocks, and cultivars of ’Qiuyue’, ’Yuluxiang’ and ’Xinli 7’ were used as scion. The effects of seed sowing timing, transplanting density of plants with pruned roots, and root-pruning treatment on the growth of grafted plants were systematically explored. The results showed that the seeds of Pyrus betulifolia sown 20 days earlier in spring lead to a 30% increase of the thickness and height of seedlings determenined in autumn when compared with the conventional sowing. The plants with pruned roots cultivated at a spacing of 15 cm in rows and wide-narrow double rows showed the best effect on the growth of the grafted seedlings. Grafted plants with pruned roots before transplanting had significantly higher amounts of lateral root, root tip, total root length, and root volume than the plants grafted without root pruning. The increased rates were 4.30 times, 2.59 times, 0.98 times and 1.34 times, respectively. The plant height growth of ’Qiuyue’, ’Yuluxiang’ and ’Xinli 7’ under strong root seedling mode increased by 21.44, 39.10, 26.97 cm, and the stem diameter growth increased by 1.99, 2.86, 3.22 mm respectively. More than 80% of grafted plants were graded as the first class. In summary, the well rooted propagation model including outdoor seed sowing in early spring and transplanting with pruned roots is conducive to produce high qualified and uniform nursery stocks of pears.更多还原