大蒜工嵌紋病對大蒜產量與品質之研究

Effect of Garlic Mosaic Virus on the Production of Garlic Plants

大蒜嵌紋病可經由蒜球傳染，田間感病株採收之種球在溫室內無傳染媒介存在之下，積植55天後95%以上具有病微，種蒜之每球蒜瓣數少（10瓣以下）而瓣徑大者，一般受嵌紋病感染程度輕為輕微，在產量方面，蒜瓣小者產量較低。蒜瓣寬平均在2.5 cm者，所種出來之每300株收獲球之幹重量為16.15 kg，瓣寬為1 cm者，則僅為7.68 kg。而黃萎病之發生率則在20~30%之間，但黃萎病發生所引起之產量損失較嵌紋病為高。田間調查發現在中部五個大蒜栽培區所種之大蒜96%以上蒜株均受嵌紋病感染，受感染之大蒜，其產量及品質顯著降低。無病微之大蒜收穫蒜球，大小平均在4.75苗cm，球重平均51.3 gm，發病植株收穫之蒜球，直徑在3.96 cm，球重亦在42.1 gm。

Garlic mosaic virus (GMV) could be transmitted through the clove of garlic, Seed bulbs of various sizes selected from infected plants in the field were grown in an insect proof green house. Fifty-five days after planting, more than 95% of garlic plants showed the GMV symptoms. Both the clove number per bulb and the size of bulbs affected virus incidence, cloves of larger size exhibited a lower percentage of virus disease. Clove from bulbs that contained less than 10 cloves also gave a lower percentage of severely diseased plants than those originating in bulbs containing 10 or more cloves. Also smaller cloves produced a lower yield, The size group of clove (having an average width of 2.5 cm) produced 16.15 kg of dry bulbs/300 plants, whereas the seed clove group having an average width of 1.0cm yielded only 7.68 kg of dry bulbs/300 plants. A field survey of five different garlic growing areas in the central part of Taiwan revealed GMV infection in more than 96% of the garlic plants. The yield and quality of infected plants were significantly decreased. The average width and weight of bulbs for symptomless plants were 4.75 cm and 51 gm, respectively, whereas for diseased plants, they were 3.9 cm and 42.1 gm respectively. Yellow dwarf was also observed in the garlic fields, infecting 10% of the plants. The disease, however caused much more yield loss than garlic mosaic.