El-Keblawy Ali, Lovett-Doust Jon
Department of Biology, Faculty of Science, University of United Arab Emirates, P.O. Box 17551, Al-Ain, UAE.
Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
New Phytol. 1998 Dec;140(4):655-665. doi: 10.1046/j.1469-8137.1998.00305.x.
Maternal-environmental effects on subsequent progeny life-history traits were evaluated in squash (Cucurbita pepo L.) in terms of the amount of time available for seed development, and the timing of fruit production. Progeny arising from three kinds of fruit were compared. Plants from which fruits were removed 3 d post-pollination throughout the growing season developed only 'late' fruits (during 10-15 d) at the end of the growing season; on control plants both 'early' and 'late' fruits developed (both types allowed to ripen fully). Seed from each type of fruit was weighed individually and categorized into three size classes, then germinated and raised to maturity, including regular harvesting of all fruits 3 d post-pollination. Maternal effects were evident for both vegetative and reproductive traits and carried over to later stages. In contrast, effects due simply to seed size disappeared by day 30 for leaf variables and day 60 for male flower production. Within a seed-size class, progeny arising from fruit of treated plants produced significantly more leaves, with greater size, and more male flowers than those arising from fruit of control plants, while the reverse was true for fruit number and fruit mass. This result is discussed in terms of possible gibberellic acid involvement. In control plants, progeny arising from seeds in the large, fully mature 'early' fruits produced significantly more, and larger leaves by day 30 than did those from late fruits (suggesting differential provisioning in seeds during development). Male flower production had a highly significant positive correlation with vegetative mass and a significant negative correlation with fruit production.
在西葫芦(南瓜属西葫芦种)中,根据种子发育可用时间和果实生产时间,评估了母体环境对后代生活史特征的影响。比较了由三种果实产生的后代。在整个生长季节,授粉后3天摘除果实的植株在生长季节结束时仅发育出“晚期”果实(在10 - 15天期间);对照植株则发育出“早期”和“晚期”果实(两种类型均让其充分成熟)。对每种果实的种子单独称重,并分为三个大小等级,然后进行萌发并培育至成熟,包括在授粉后3天定期收获所有果实。母体效应在营养和生殖性状方面均很明显,并延续到后期阶段。相比之下,单纯由种子大小引起的效应在第30天时对于叶片变量消失,在第60天时对于雄花生产消失。在一个种子大小等级内,处理植株果实产生的后代比对照植株果实产生的后代长出更多、更大的叶片以及更多的雄花,而果实数量和果实质量方面则相反。根据可能涉及赤霉素的情况对这一结果进行了讨论。在对照植株中,来自大型、完全成熟的“早期”果实种子的后代在第30天时比来自晚期果实的后代长出显著更多且更大的叶片(表明发育过程中种子的营养供应存在差异)。雄花生产与营养质量呈极显著正相关,与果实生产呈显著负相关。