已知抗瘟基因在黑龙江省寒地稻区的评价与利用

 利用12个日本鉴别品种、7个中国鉴别品种、24个抗稻瘟病单基因系及6个当地主栽品种，对2006年采自该省主要积温区不同水稻品种的178个稻瘟病菌株进行了致病性测定。结果表明：2006年黑龙江省稻瘟病菌生理小种划分为104个日本小种，077.7号生理小种比例最高为4.49%，017.1号、017.5号、037.5号生理小种出现频率为3.93%。就抗性基因而言，抗瘟基因Pi9(t)在全省抗谱为97.75%，是较好的抗源可以在全省内广泛利用；Piz-5、Pi12(t)抗瘟基因抗谱分别为78.09%和78.65%，根据品种种植区域可以有选择地利用。就品种而言，抗瘟基因Pi9(t)、Piz-5是空育131；Pi5(t)、Pita-2是垦稻10号；Pi9（t）、Pita是上育397；Piz-5、Pi12(t)是垦稻12号等品种抗瘟改良的有利基因；在研究中同时加强对稻瘟病菌种群的监测和新抗源的发掘，有针对性地向主栽品种导入新的抗性基因。

Evaluation and utilization of value of twenty-four blast resistance genes in north cold region,Heilongjiang

A total of 178 Magnaporthe oryzae (M. oryzae) isolates, collected from different rice-cropping districts of Heilongjiang Province in 2006, were tested for pathogenicity against 12 Japanese and 7 Chinese differential varieties (DVs), 24 rice monogenic lines (MLs) with different blast resistance genes and 6 local leading cultivars. The results showed that 104 Japanese races (pathotypes) were identified and the predominant ones were 077.7, 017.1, 017.5 and 037.5. Resistance gene Pi9(t) expressed the broadest resistance spectrum (on average 97.75%) to all the blast isolates tested, and was of the highest utilization value in rice resistance breeding. Resistant genes Piz-5 and Pi12(t) also showed high utilization values due to their resis-tance spectra were 78.09% and 78.65%. The results showed that some resistance gene could upgrade the blast resistance of rice varieties, for example, Pi9(t) and Piz-5 upgrade the blast resistance of Kong Yu 131; Pi5(t) and Pita-2 upgrade the blast resistance of Ken Dao 10; Pi9(t) and Pita upgrade the blast resistance of Shang Yu 397; Piz-5 and Pi12(t) upgrade the blast resistance of Ken Dao 12. Simultaneously, the new resis-tance resources will be explored extensively and the new broad-spectrum resistance genes will be transfered into leading cultivars purposefully.