Responses of VA mycorrhizal Fungus, Glomus mosseae, on the Growth and Nutrition of Mulberry tree

VA 내생균근균, Glomus mosseae,가 뽕나무의 생장과 영양에 미치는 영향

This study was carried out to acguire some basic information on nutritional and lhysiological effects of vesicular arbuscular mycorrhizae(VAM) on mulberry trees inoculated with Glomus mosseae, Gerd. & Trap. grown in clay for 65 days and treated with 5 different levels of phosphorus, ie 30, 60, 120, 240, 480 ppm as (NH4)2 HPO4. At the End of the expermental period the levels of fixed phosphate in the soil was measared. And the native VAM fungi were collected to select the most effective VAM species on mulberry tree. The nutritional and biochemical effects of VA mycorrhizae on the mulberry leaves were also studied. Those results are as follow. 1. The mulberry trees grown in clay and inoculated with VAM were heavier in shoot dry weight as much as 197% than uninoculated plants. But in vermioulite, uninoculated mulberry trees were heavier as much as 135% than inoculated. 2. The rates of endo mycorrhizal formation in clay was highest at 60 ppm level of phosphorus, and vesicles in roots were formed in 240ppm and 480ppm level of phosphorus, but not in 30ppm, 60ppm and 120ppm. 3. The greatest growth responses of VAM inoculation was found at 60ppm level of hosphorus, and the optimum phosphorus level for VAM responese appeared to be 60ppm. 4. VAM was also to absorb soil-fixed phosphate. VAM abosrbed Fe-bound phosphate most efficiently and Ca-bound phosphate with ease but not Al-bound phosphate and Al-Fe occluded phosphate. 5. Three species of Gigaspora and one species of Glamus growing naturally in mulberry plantations were collected and tested for the growth responses. Gigaspora tricalipta and Gigaspora calospora revealed the greatest growth responses on mulberry tree among tested VAM fungi. 6. Mulberry leaves inoculated with VA mycorrhizal fungi contained 9.8% more phosphate and 15.2% more nitrogen, 22.2% more water-soluble carbohydrates and 15.2% more proteins than uninoculated plants. 7. The electrophoretic pattern of mulberry leaf protein inoculated with VAM fungi has 19 bands. 8. The patterns of peroxidase zymogram and Amulase zymogram were different between the mulberry leaves inoculated and uninoculated with VA mycorrhizal fungi. The peroxidase zymogram of inoculated leaves has 1 less majour band than unioculated leaves The amylase zymogram of inoculated leaves has 2 bands near the +pole, but that of uninoculated leaves has 1 band near the $pole.

VA 내생균근이 뽕나무의 생장과 뽕잎증의 양육물질, 효소에 미치는 영향을 조사하고 뽕나무에 알맞는 균근을 선발하기 위하여 전국 6개 잠업주산지 뽕밭과 2개소의 산뽕나무 자생지에서 VA 내생균근을 모집, Bio-assay를 실시하였다. 그 결과는 다음과 같다. 1. VA 내생균근을 접종한 뽕나무는 접종하지 않은 뽕나무에 비하여 황토에서는 97%의 생장촉진 효과가 있었고 Vermiculite에서는 35%의 생장억제가 있었다. 2. VA 내생균근의 형성은 인산 60ppm 수준에서 가장 왕성하고 30ppm과 480ppm에서는 억제 됐으며 Vesicle은 인산 240ppm 이상 수준에서만 형성되었다. 3. VA 내생균근에 접종된 뽕나무는 인산 60ppm 수준 이상에서 생장이 가장 왕성하였으며 균근의 형성도 가장 왕성하였으므로 가장 알맞는 인산수준은 60ppm으로 생각된다. 4. VA 내생균근은 토양 중의 Fe-bound phosphate를 가장 잘 흡수하고 Ca-ound phosphate도 일부 흡수하였으나 Al-bound phosphate와 Al-Fe occuded phosphate는 흡수하지 못하였다. 5. VA 내생균근은 뽕잎의 인산은 약 10%, 실소는 15% 증가시켰으며 탄수화물은 22%, 단백질은 15% 증가시켰다. 6. 단백질의 전기영동상은 접종하지 않은 것은 16개의 band가 나타났으나 접종한 것은 19개의 band가 나타났다. 7. VA 내생균근은 뽕잎의 Peroxidase와 Anylase zymogram pattern을 변화시켰으며 특히 Amylase zymogram은 균근을 처리하지 않은 것과 큰 차이가 있었다. peroxidase zymogram은 균근을 접종한 것은 접종하지 않은 것에 비하여 주요 band가 한 개 더 적었고 amylase zymogram은 균근을 접종하지 않은 것은 band가 한 개이고 (-)극에 가까운 곳에 나타났으며 접종한 것은 band가 2개이었으며 (+)에 가까운 곳에 나타났다. 8. 우리나라 잠업 주산단지와 산뽕나무 Gigaspora속 3종과 Glomus속 1종을 선발하였으며 Bioassary를 한 결과 Gigaspora tricalipta와 Gigaspora Calospora가 뽕나무 생육에 가장 큰 생장촉진효과가 있었다.