Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/65647
標題: 杉木抗葉枯病之早期遺傳篩選試驗
Early Resistance Screening of China fir to Leaf Blight
作者: 黃妙霖
Haung, Miao-Lin
關鍵字: 杉木葉枯病;Leaf Blight of China fir;香杉;人工接種;遺傳率;抗病篩選;莖根比;Cunninghamia lanceolata;artificial inoculation;heritability;resistance selection;T/R ratio
出版社: 森林學系
摘要: 
臺灣的杉木林及苗圃經常受到杉木葉枯病的危害,是幼苗時期與生長後期的重要病害
之一,其中以幼苗至七、八年生的造林木在潮濕多雨的季節最易受害。引起杉木葉枯病之
病原菌為白井擬盤多毛菌(Pestalotia shiraiana P. Hennings),屬真菌之一種。
本實驗採用香杉種子園單親家系,分別在生長室及溫室進行試驗,將幼苗區分成噴菌
組與對照組進行人工接種。生長室與溫室幼苗在接種前,定期量測其生長高度,人工接種
病原菌後三星期調查幼苗之感病情形。
校區兩生長室幼苗的絕對生長表現,經由變方分析結果顯示不一致。在溫室方面,遺
傳率估計值頗高,顯示家系間的遺傳變異甚大,可在家系間進行早期選拔。
生長室與溫室之罹病度分析,顯示各家系之感病程度不同;在「感病與否」及「感病
葉是否超過十」兩性狀上,兩試驗地之分析結果卻有差異。校區生長室5家系兩性狀之二
元數據linear logistic model分析差異並不顯著,溫室13個家系在「感病與否」性狀以
相同模式分析差異卻為顯著;因此未來可在溫室進行抗病篩選,育成具抗病力之幼苗。
將校區生長室罹病等級與生長量一起納入分析,結果顯示各罹病等級幼苗地上濕重/
地下濕重之比值(T1),及幼苗地上乾重/地下乾重之比值(T2)變異顯著,與幼苗罹病等級
之平均值相比較,顯示比值愈大者其罹病等級愈高。在溫室方面,將各家系罹病度與幼苗
最後一次量測高度作多變域分析及相關性估計,結果顯示兩性狀間相關性頗高;此點與前
述之校區生長室莖根比(T1、T2)與罹病度成正比之結論一致,可供預測各
家系感病力之用。
總括來說,實驗結果顯示生長室與溫室各家系之生長與抗病表現兩者間具相關性,故
可以幼苗高度作為早期測試抗病力之間接選拔性狀。

China fir (Cunninghamia lanceolata) has long been damaged by Leaf Blight of
China Fir, a common disease which attacks the species from seedlings in nursery
to saplings in the plantation. Plantations at ages 7~8 are particularly suscep-
table. The causal agent of disease was isolated and identified as Pestalotia
shiraiana P. Hennings.
Current study involves seedlings of open-pollinated single-tree families
from a local seed orchard in Taiwan. Seedlings were grown in both growth chamb-
ers and greenhouse. Before artificial inoculation of the
fungus, young seedlings
(less than one year)were regularly measured for plant heights.
Three weeks after
inoculation, these seedlings were investigated for their disease-resistance and
growth traits.
For growth traits: in the growth-chamber experiment, five families were
involved for the study. Analysis of variance results showed that plants in dif-
ferent chambers behaved differently in their growth, which suggested a GE
interaction effect. In the greenhouse experiment, where 13 families were used,
heritability estimates were high, which implies large between-families varia-
tion. Thus early selection was possible.
For disease-resistance traits: susceptibility degrees were calcu-lated in
both experiments. Results showed that there was a significant between-families
variation. However, two symptom traits (healthy/sick, whether the number of
infected leaves are more than 10 leaves)showed inconsistent results between the
two experiments. Linear logistic model for the growth-chamber
experiment did not
show significant result. However, the same statistical model
applied in the data
analyses of greenhouse experiment clearly demonstrated that there were signifi-
cant difference in resistance among 15 families.
In growth-chamber experiment, we have also measured green- and oven-dried
weights of above- and below-ground parts of the plants. It was found that the
T/R ratio showed significant difference among seedlings of different classes of
susceptibility classes. The larger the T/R ratio, the plants
showed more serious
signs of damage. In the greenhouse experiment, plant height just prior to inoc-
ulation showed positive correlation with individual*s susceptibility degree.
These results are valuable information and worthy for further investigation.
In general, results demonstrated that early testing of genetic entries of
Cunninghamia lanceolata for disease-resistance to Pestalotia shiraiana P.
Hennings was possible.
URI: http://hdl.handle.net/11455/65647
Appears in Collections:森林學系

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