Multinucleate storage cells in Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) and the effect of seed parasitism by the chalcid Megastigmus spermotrophus Wachtl
Multinucleate storage cells in Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) and the effect of seed parasitism by the chalcid Megastigmus spermotrophus Wachtl
复制标题
花旗松 (Pseudotsuga menziesii (Mirbel) Franco) 中的多核贮藏细胞和 Chalcid Megastigmus sporotropicus Wachtl 对种子寄生的影响
作者：
P. Aderkas;G. Rouault;R. Wagner;S. Chiwocha;A. Roques
花旗松 (Pseudotsuga menziesii (Mirbel) Franco) 的巨型配子体在受精后积累储存产物。随着巨型配子体的成熟，每个细胞的细胞核数量增加，形成合胞体储存细胞。在法国和加拿大对树木进行的研究证实，这种以前未报道的游离核细胞是晚期巨型配子体发育的正常部分。未受精的大配子体显示，一些双核细胞在退化之前导致空种子。昆虫寄生可防止未受精胚珠中的大配子体流产。在大配子体发育早期，大配子体发育过程中，小黄蜂（Megastigmus sporotropicus Wachtl）的产卵导致了正常的大配子体发育。在植物卵成熟前后，观察到双核和三核细胞。当大配子体成熟时，形成富含蛋白质、脂质和淀粉的多核成熟储存细胞。该昆虫能够在受感染、未受精的大配子体中诱导出与未受感染、受精的大配子体相同的核行为。
Megagametophytes of Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) accumulated storage products following fertilization. As megagametophytes matured, the number of nuclei per cell rose, resulting in syncytial storage cells. Studies carried out on trees in France and Canada confirmed that such previously unreported, free nuclear cells were a normal part of late megagametophyte development. Unfertilized megagametophytes showed that some binucleate cells before degeneration resulted in empty seed. Insect parasitism prevented megagametophyte abortion in unfertilized ovules. Oviposition by a torymid chalcid wasp (Megastigmus spermotrophus Wachtl) early in megagametophyte development resulted in normal megagametophyte development. Around the time of plant egg maturation, binucleate and trinucleate cells were observed. As megagametophytes matured, multinucleate mature storage cells rich in proteins, lipids and starch were formed. The insect was able to induce identical nuclear behaviour in infested, unfertilized megagametophytes, as that of uninfested, fertilized megagametophytes.