连续5年施用生物有机肥对梨树根系形态及分布的影响

[目的]探究连续5年施用生物有机肥对‘黄冠梨’树根系形态及分布特征的影响，为梨园高效施肥提供理论依据。[方法]在15年生‘黄冠梨’上设置不施肥（CK）、化肥（TF）和生物有机肥（BOF）3个处理，采用环施法施肥，果实采收后在距树干水平方向0~200 cm、垂直方向0~120 cm，按40 cm×40 cm×30 cm采集20个土体单元，研究不同处理下梨树根系在水平和垂直方向上不同径级根系的根长、根表面积和根体积的分布特征。[结果]梨树根系总的根长、根尖数、根表面积和根体积均以BOF处理最多，TF处理次之，CK最少。与CK相比，BOF处理梨树总根长、总根尖数、总根表面积、根体积分别增加71.8%、50.8%、89.9%和130.1%，比TF处理增加28.0%、8.3%、37.0%和61.5%；不同径级根长密度、根表面积和根体积均以BOF处理最多，TF处理次之，CK最少。3个处理下，根系均主要分布在0~120 cm水平方向、0~90 cm垂直方向。在此范围内，0~60 cm垂直深度土层，生物有机肥处理显著提高了根尖数，促进了细根（<1 mm）的生长；0~90 cm垂直深度土层，显著促进了1~3 mm径级根系生长；在60~90 cm垂直深度土层则显著促进了粗根（>3 mm）的生长。BOF处理提高了0~60 cm土层深度土壤有机质、速效钾、碱解氮和速效磷含量。[结论]生物有机肥处理能够显著促进不同深度、不同径级根系的生长，有利于提高根系对土壤水分和养分的吸收。
[Objectives]This paper was aimed to investigate the influence of continual supplied bio-organic fertilizer for five years on the root morphology and distribution of ‘Huangguan’ pear,with provides theoretical basis for high efficiency fertilization in pear orchard. [Methods]The experiment was designed with two fertilizer types,i.e.,chemical fertilizers (TF)and biological organic fertilizer (BOF),and a non-fertilizer control (CK)on 15-year old ‘Huangguan’ pear trees. All fertilizers were supplied by annular fertilization method,and 20 soil units with 40 cm×40 cm×30 cm were collected in the range of 0-200 cm (horizontal distance)from the trunk and 0-120 cm (vertical distance)after fruit harvest. The characteristics of length,surface area and volume of different diameter pear tree roots on the horizontal and vertical directions were investigated. [Results]The total root length,total root tip numbers,total root surface area and total root volume of pear roots were the most in BOF,followed by TF,and the least in CK. Compared to control,the total root length,total root tip numbers,total root surface area and total root volume of BOF treatments increased by 71.8%,50.8%,89.9% and 130.1%,respectively,and increased 28.0%,8.3%,37.0% and 61.5%,respectively,compared to TF. The root length,root surface area and root volume in different diameter roots were also the most for BOF,and the least for the CK. The pear tree roots mainly distributed in the range of 0-120 cm (horizontal distance)from the trunk of 0-90 cm (vertical distance)in all treatments. BOF significantly increased the root tip number and promoted the growth of fine roots (<1 mm)in the area of vertical depth 0-60 cm;and promoted the growth of 1-3 mm roots in the area of vertical depth 0-90 cm;the growth of thick roots (>3 mm)were significantly promoted between vertical depth 60-90 cm. BOF improved the content of soil organic matter,available potassium,available