Study on the seed weight and seed seize variation pattern and their biological sinificance in Podophylloideae (Berberidaceae)
MA Shao－bin;JIANG Han－qiao(Biology Department. Yunnan University, Kunming 650091; Kunming Institute of Botany, Chinese Academy of Science.Kunming 650205)
The seed weight and seed size and their variation pattern of four species (including Sinopodophyllum hexandrum,Dyssosma veitchii,Diphylleia sinensis and Podophyllum peltatum) in Podophylloideae (Berberidaceae) have been detailly analysed,the result shows that: ① In the four species,Dysosma veitchii has biggest seed,the seed weight is 37. 24±6. 71mg,Sinopodophyllum hexandrum has smaller seed,its seed weight is 36.56±4.54mg:Podophyllum peltatum has smallest seed,the seed weight is 19. 01±3. 21mg,the seed of hohylleia sinensis is somewhat weight than that of Podophyllum pelta tum, its weight is 23.22±3. 26. ②All species contains a partion of nonviale seed,the percentage for Sinopodophyllum hexdrabum is 1.0%, fososma veilchii is 6.0%, DLphylleia sinensis is 5. o% and PodoPhyllu;n peltatum is 3. 5%. ③The variation pattern of seed size has close relationship with pollination,allogamy species has larger variation than that of autogamy species. ④Seed size and seed weight has close relationship with plant living environment, those species which 1iving in the environment of stable, less disturbed and high coverage degree has bigger and weighter seed than those living in open, frequent1y disturbed and damp environment. Different populations of a species have different seed weight,a example is that seed weight of Sinopodaphyllum hexandrum is close related with altitude,the higher altitude,the lighter of seed weight. ⑤Among species,seed weight has no obviously relationship with fruit number,fruit size and seednumber in the fruit,but the larger seed number a plant produces,the lighter is its seed weight. But within species,seed weight has close relationship with seed number in fruit,the more seed in a fruit,the lighter its seed weight,and usually the larger the fruit,the lighter seed it contains.