萌发条件对水稻双苗率的影响

The Effect of Germinating Conditions on the Frequency of Twin Seedlings in Rice

通过对双－３、双－１３、陆５２和阿里希斯尼４个多胚水稻品系的研究，结果表明多胚水稻的双苗（多苗）性状表达受萌发条件的影响：１．种子去壳后浸种催芽较未去壳浸种催芽的双苗率平均提高２．７％，最高为３．８％。在组织培养条件下萌发，其双苗率的提高更明显，平均为４．４％，最高为７．４％（双苗率由４１％提高到４８．４％）；２．在接种前对种子不同温度的预处理研究表明，温度对双苗率也有较大的影响：二个粳稻品种和籼稻品种双－１３的最适温度为５０℃；籼稻品种双－３的最适温度为３０℃，在此温度预处理后，最高双苗率由４１．０％提高到７５．０％。

Polyembryonic rice is a good material for apomixis research. In order to study the relation between the frequency of twin seedlings (include poiyembryonic seedlings ) and the germinating condition, the paper based on a series experiments with four polyembryonic rice varieties: SHUANG- 3.SHUANG-13 LU52 ALIXISINI. The results shown that the seeds without shell has higher frequency compared with the seeds with shell in germination. The average value increased is 2. 7 percent, the highest value increased is 3. 8 percent. In germination induced in culture, the frequencies of twin seedlings have been evidently increased, the average value increased is 4. 4 percent, the highest value increased is 7.4 percent(from 41.0 to 48.4 percent). The results indicated that the frequency of twin seedlings is affected by pretreatment before inoculation. We found that the optimum temperature for two japonica polyembryonic rice and one indica rice is 50℃, but it is 30 ℃ for another indica rice. In the optimum temperature. the frequencies of four polyembryonic rice are increased in a large scale. the highest is from 41.0 to 75.0 percent.