Effects of Application Date of Antibiotic on Seedlessness and Berry Size in 'Muscat of Alexandria'and Neo Muscut'Grapes

A study on the effects of the application date of antibiotic on seedlessness and berry size was conduced using 'Muscut of Alexandria'(MOA) and 'Neo Muscut'(NM) grapevines. Two antibiotics were used as seedlessness inducer,streptomycin(SM) and spectinomycine(SE) applied in the concentoration of 200mg/L by dippinng the clusters.The tested of dates of application were 6 and 3 days before full bloom, at full bloom (50% anthesis),and 5days after full bloom.The 3-days before full bloom application gave the highest percentage of seedless berry within each antibiotic in both cultivars.Application after than 3days before full bloon increased production of empty-seeded berries, though the later application was able to increase the berry size and berry weight.

'マスカット・オブ・アレキサンドリア’と’ネオ・マスカット’について、無核化のために行う抗生物質処理の時期がその効果と果粒の肥大に及ぼす影響を調査した。無核化剤としてストレプトマイシンとスペクチノマイシンを用い、満開日（小花の50％が開花）とその6,3日前、および5日後に200ｍｇ/MLで果房の浸漬処理を行った。両品種とも、3日前に各抗生物質を処理すると無核化率が最も高かった。それより遅い処理では果粒サイズは大きかったが、空洞種子（empty seed) を含む果粒が多く着生した。