Department of Life Science, College of Life Sciences, Jilin Normal University Siping, China.
Front Plant Sci. 2014 Oct 6;5:528. doi: 10.3389/fpls.2014.00528. eCollection 2014.
HIGHLIGHTSIn an abortive ovary of hazel, an integument seldom differentiated and a mature embryo sac never developed.In an abortive ovary of hazel, pollen tube growth was arrested at the style base about 40 days after blooming. Thus, fertilization of the ovule was precluded.Ovary abortion in the four hybrid cultivars was indicated to be associated with insufficient resource availability to support fruit set by all flowers, whereas ovary abortion in C. heterophylla was at least partly determined by pollen availability. In Northeast China, a high frequency of ovary abortion contributes to serious losses in yield of hazelnut. The development of pistillate inflorescences and fruit clusters of four large-fruited hybrid hazel cultivars and the small-fruited Corylus heterophylla were used to study ovary abortion and its possible causes during the progamic phase in hazel. The average number of pistillate (ANP) flowers per inflorescence and average number of fruit (ANF) per cluster of four hybrid hazel cultivars were 7.6-8.5 and 2.4-3.0 respectively; in C. heterophylla, its ANP and ANF was 5.8-6.2 and 3.5, respectively. The total drop varied from 50 to 67%. Ovary abortion in hazel initiated from about 30 days after blooming. The percentage of abortive ovaries (PAO) in the four hybrid hazel cultivars ranged from 63 to 72%, and was significantly higher than that of C. heterophylla (29-42%). Only the abortive ovary ratio of C. heterophylla was significantly reduced after artificial pollination. Fruit number per cluster was positively and negatively correlated with yield and nut mass, respectively. In abortive ovaries, the diameter remained less than 2 mm during the entire fruit development, an integument seldom differentiated and a mature embryo sac never developed. In addition, pollen tube growth was arrested at the style base about 40 days after blooming. Thus, fertilization of the ovule was precluded. Compared with abortive ovary, starch content in developing ovary of four hybrid hazel cultivars and C. heterophylla were significantly higher. This study suggests that abortive ovary was incapable to finish fertilization process due to the absence of mature embryo sac and arrested pollen tubes, and this is likely associate with insufficient resource availability to support fruit set by all flowers in four hybrid hazel cultivars, whereas ovary abortion in C. heterophylla is at least partly determined by pollen availability.
在榛树败育的卵巢中，很少有内果皮分化，也从未发育出成熟的胚囊。
在榛树败育的卵巢中，花粉管在开花后约 40 天在花柱基部停止生长。因此，胚珠的受精被阻止了。
四个杂交品种的卵巢败育表明与资源不足有关，无法支持所有花朵的果实结实，而 C. heterophylla 的卵巢败育至少部分取决于花粉的可用性。在中国东北，卵巢败育的频率很高，导致榛子产量严重损失。
为研究榛 progamic 阶段的卵巢败育及其可能的原因，利用四个大果杂交榛品种和小果榛子的雌花序和果实簇的发育来研究卵巢败育。四个杂交榛品种的每个花序的雌花（ANP）数和每个簇的果实数（ANF）分别为 7.6-8.5 和 2.4-3.0；在 C. heterophylla 中，其 ANP 和 ANF 分别为 5.8-6.2 和 3.5。总脱落率从 50%到 67%不等。榛树的卵巢败育始于开花后约 30 天。四个杂交榛品种的败育卵巢百分比（PAO）范围为 63%至 72%，明显高于 C. heterophylla（29%-42%）。只有 C. heterophylla 的败育卵巢比例在人工授粉后显著降低。每个簇的果实数与产量和坚果质量呈正相关和负相关。在败育的卵巢中，整个果实发育过程中直径一直小于 2 毫米，内果皮很少分化，也从未发育出成熟的胚囊。此外，花粉管在开花后约 40 天在花柱基部停止生长。因此，胚珠的受精被阻止了。与败育卵巢相比，四个杂交榛品种和 C. heterophylla 发育中的卵巢中的淀粉含量明显更高。
本研究表明，败育卵巢由于缺乏成熟的胚囊和停止生长的花粉管，无法完成受精过程，这可能与四个杂交榛品种中所有花朵的果实结实所需的资源不足有关，而 C. heterophylla 的卵巢败育至少部分取决于花粉的可用性。
