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观察各种果树从授粉到受精所需时间,有利于培养学生的观察能力以及分析、解决问题的能力。现将测定方法简介如下: 在果树铃铛花期(少数花开放多数还未开放,呈灯笼状),选健壮的苹果或梨树,用镊子剥去花瓣,轻轻去掉雄蕊,然后用报纸或其他结实的白纸做成的20×15厘米的口袋将整个花枝套住,在果枝基部用线把袋扎紧。挂上纸牌并用铅笔记录去雄时间。一般每组应去雄套袋80个花序左右。
Observation of a variety of fruit trees from pollination to fertilization time, help to develop students’ observation ability and ability to analyze and solve problems. Now the determination of the method are as follows: In the flowering period of the fruit tree bell (most of the flowers are not open, most are lanterns), choose robust apple or pear tree, stripped petals with tweezers, gently remove the stamens, and then use newspapers or other firm Of white paper made of 20 × 15 cm pockets of the entire flowering nest, in the base of the branches with a line tie the bag tightly. Hang up the cards and use a pencil to record the time to emasculate. In general, each group should go to the bag around 80 inflorescences.