サンショウ花粉の人工培地上での発芽に及ぼすショ糖濃度,培養温度およびホウ酸濃度の影響(栽培管理・作型)  [in Japanese] Effects of Sucrose and Boric Acid Concentration, and Incubation Temperature on Germination of Japanese Pepper (Zanthoxylum piperitum (L.) DC.) Pollen on Artificial Media(Crop Production & Cropping Type)  [in Japanese]

実サンショウの高価格販売には,ハウス栽培による早期出荷が有効である.しかし,一般的に他家受粉を必要とする作物のハウス栽培では単位面積当たりの収量を増加させるために,人工受粉技術を確立する必要がある.人工受粉での結果率を高めるためには,発芽率の高い花粉を用いる必要があり,受粉に用いる花粉の発芽能力を知るための好適な培地条件を明らかにする必要がある.そこで,開花初期および盛期の新鮮花粉を用いて,ショ糖濃度およびホウ酸濃度の異なる寒天培地上における花粉発芽率を求めるとともに花粉管長を測定し,好適な培養温度も検討した.その結果,2%寒天培地上での開花初期および盛期の花粉発芽率は,培地のショ糖濃度がそれぞれ15%および15〜20%で高く,両時期の花粉ともに花粉管長はショ糖濃度が15〜25%で比較的優れた.培養温度は両時期の花粉ともに30℃で発芽率が高くなり,花粉管長は開花初期および盛期の花粉でそれぞれ20〜30℃および15〜35℃で比較的優れた.また,20%のショ糖を含む2%寒天培地に100〜1000ppm濃度のホウ酸を添加した結果,花粉発芽および花粉管長が促進された.

Early shipping of immature fruit of the Japanese pepper (Zanthoxylum piperitum (L.) DC.) grown under greenhouse conditions is advantageous for commanding a higher price for the fruit. However, in order to achieve a yield per unit area of fruit under greenhouse conditions, artificial pollination is required. For successful pollination, pollen with a high potential for germination must be used. Additionally identification of optimal conditions for pollen germination is also required. In this paper, we identified the optimal concentrations of sucrose, agar, and boric acid, as well as the optimal temperature for pollen germination and pollen tube length for fresh pollen of Japanese pepper at the beginning of flowering and the full bloom stage under an artificial environments. With 2% agar media, the highest percentage of germination at the beginning of flowering and at the full bloom stages were obtained at 15% and 15-20% respectively. Pollen tube length at both times excelled comparatively at 15-25% sucrose. The highest germination at both times was obtained at 30℃. Pollen tube length at the beginning of flowering and full bloom stage were comparatively higher at 20-30℃ and 15-35℃, respectively. Adding 100-1000ppm boric acid enhanced pollen germination percentage and tube length.