落叶松枯梢病寄主抗性的研究

STUDY ON THE HOST RESISTANCE TO LARCH SHOOT-BLIGHT

对东北地区落叶松枯梢病［Ｂｏｔｒｙｏｓｐｈａｅｒｉｓｌａｒｉｃｉｎａ（Ｓａｗａｄａ）Ｓｎａｎｇ］的寄主抗病性进行了系统研究，在抗病良种筛选研究中得出：（１）落叶松枯梢病多发生于６～２５年生幼林和成林，不同品种、品系、种源的抗病性不同、同一品种、品系、种源的不同年龄、不同立地条件发病不同；（２）东北地区落叶松品种、品系抗病序列为日５、日５×兴１２、日５×兴９、兴１２×日５、兴６×兴９、日１２、兴９×日７６－２、长７８－５、长７８－１５、兴１３×兴９。长白落叶松种源抗病序列为小北湖、白刀山、白河、大石头、和龙、汪清、天桥岭、黄泥河；（３）综合抗性、生长量、形质三项指标．筛选出日×兴、兴×日、日×长、日５×兴１２、兴１２×日５５个品系为抗病优良品系，小北湖长白落叶松为抗病良种种源。在抗病机制研究中确定了当年枝梢钾、锰含量低时则抗病，健康落叶松品种、品系的过氧化物同工酶（ＰＯＤ）与抗病性关系不明确，但患病后ＰＯＤ则发生一系列变化。

The host resistance to larch shoot-blight caused by Botryosphaeria Laricina(Sawada) Shang in northeast China was studied systematically. The results ofscreening for the fine resistant varieties are as follows:(1) The larch shoot-blightoccurs mostly in the 6 ～25 years old young and ripe stands. The host resistanceis different from the varieties, strains and provenances. The seventy of thedisease is different from the ages and sites among the same variety, strain orprovenance. (2) The resistant rank of the variety and strain to larch shoot-blightin northeast China are Larix kaempferi ' 5', L. kaempferi' 5'×gmelini' 12'. L. kaempferi' 5'× gmelini' 9'. L. gmelini' 12' × kaempferi' 5'.L.gmelini' 6'×' 9', L. kaempferi' 12', L. gmelini' 9'× kaempferi' 76-2'. L. olgensis var.chanpaiensis '78-5'. L. olgensisvar. chanpaiensis' 78- 15', L. gmelini' 12' ×' 9'; The provenanceresistant rank of Larix olgensis var. chanpaiensis is' Xiaobeihu',' baidaoshang'' Bathe';' Dashitou'.' Helong'.' Wangqing',' Tianqiaoling'.' Huangnihe'; (3) The five varieties including Larix kaempferi ×gmelini. L. gmelini; × kaempferi, L. kaempferi × olgensis var. chanpaiensis.h. kaempferi' 5' × gmelini' 12'. L. gmelini' 12' × kaempferi' 5' arescreened as fine varieties according to resistance, groWth increment and formfactor indexes. The researching results of the resistant mechanism are asfollows:(1) The ions concentration of kalium (K+) and manganese(Mn++) and thecontent of catechin in one-year-old tip of branches are important for determining the host resistance, the host appears resistant to larch shoot-blight when theions concentration of K+ and Mn++ are lower and the content of catechin arehigher; (2) The relationship between the health host's peroxidase (POD) isozymeand the host reistance isn't definite, but a series of changes happened aft.er thehost was infected.