Please use this identifier to cite or link to this item:
Effects of GA3 on Interspecific Hybridization of Arachis Species
以栽培種花生A. hypogaea (TNS9)為母本，與野生種花生A. paraquariensis, A. duranensis, A. batizocoi 及A. pusilla進行種間雜交，每個雜交組合分別以不同濃度50、100、150 ppm之GA3處理，就組織學上探討花生种間雜交等不稔的原因，及雜交胚發育的特性。調查子房柄、未熟莢等之形成率及子房柄形成日數與長度，分別於授粉後2、4、6小時取授粉之母本子房（雌蕊）及於子房柄形成後7、14、21 及28天的雜交胚，利用螢光顯微鏡與位相差顯微鏡觀察雜交後花粉管之伸長情形與雜交胚及胚乳發育情形，結果如下：
1. 四個組合之對照處理(CK)的子房柄形成率平均為10%，且大部份子房柄均不能伸入土壤中；獲得雜交之未熟莢形成率平均為2.1%。以不同濃度GA3 50、100及150ppm處理，子房柄形成率平均為84.5%，且大部份子房柄均能伸入土壤中，獲得雜交未熟莢平均為4.4%。可見GA3處理可促進花生种間雜交子房柄之形成。
2.就四個雜交組合的平均而言，子房柄形成所需日數不施用GA3者為31天；以GA3 50 ppm處理者均為15天；100 ppm處理者平均為9天；150 ppm處理者平均約為8天。顯示GA3處理可縮短子房丙形成所需日數。
3.就四個雜交組合的平均而言，不施用GA3者，子房柄長度生長到14天平均為7.1mm，以GA3 50 ppm處理者為43.2mm, 100ppm為54.77, 150 ppm為54.3mm。證明GA3處理不但可促進子房柄伸長，且大部份子房柄均可伸入土壤中。
5.TNS9 x A. duranensis處理GA3 150ppm 7天後，雜交胚發育未成形，14天後胚發育至圓球形前期，21天後胚發育至圓球形後期，28天後胚發育至心臟形期、胚乳幾乎全部消失。TNS9 x A. batizocoi 處理GA3 100及150 ppm，胚發育至7天及14天皆未成形，21天及28天胚發育至圓球形，其他雜交組合胚均停滯發育而未成形。
Interspecific hybridizations were made by crossing A.hypoqaea (TNS9) (as female parent) with A. paraquariensis, A. duranensis, A. batizocoi and A. pusilla Im-mediately after pollination, the flowers were treated with GA3 of different concentrations, i. e., 50, 100, and 150 ppm. The causes of sterility of interspecific hybridization and the development process of hybird embryos wer investigated from a point of histological view. The days from pollination to peg formation, the rates of formation of pegs and immature pods and the length of pegs were examined. The ovaries at 2, 4 and 6 hours after pollination and hybrid embryos at 7, 14, 21 and 28 days after peg formation were collected, The elongation of pollen tubes after pollination and the development of hybrid embryos (and endosperms) were observed with flouescence microscope and phase contrast microscope Results are summerized as follows:
1. In the GA3 free treatment the mean rate of peg formation was 10% and most pegs didn''t penetrate into soil, and mean rate of immature hybrid pods Iornfion was 2.1%. No mature pod was obtained. when troated with GA3 of 50, 100 and 150 ppm, respeccively, the mean rate of peg formation was 84.5% and most pegs could penetrate into the soil. The mean rate of immature hybrid pods formation was 4.4%. The peg formation of interspeoific hybridization in Arachis was enhanced by the application of GA3.
2. Averaged over the four cross combinations, the mean days to peg formation in the GA3-free treatmean was 31 days, and those treated with 50, 100 and 150 ppm CA3 were 15 days 9 days and 8 days, respectively. The days to peg formation was shortened by the treatment of CA3.
3. Averaged over the four cross combinations, a mean peg length of 7.1mm was observed at 14 days after peg formation in the CA3-free treatment. Those treated by 50, 100 and 150 ppm GA3 gave a mean peg length of 43.2, 54.77 and 54.3mm, respectively. with the CA3 treatment, peg growth was enhanced and most pegs could penetrate into thesoil.
4. In the GA3-free treatment, 40% and 80% of the pollen tubes had reached the ovules by the second and the fourth hours after pollination, while all the pollen tubes had elongated into ovules by the sixth hours after pollination. when treated with GA3, all the pollon tubeso had elongated into ovules by the second hour after pollination.
5. In the cross of TNS9 x A. duranensis treated with 150 ppm CA3, the fertilized ovules didn''t develop until 7days after peg formation, but pro-sphearical embryos appeared on the 14th day , the post-sphearical embryos appeared on 21st day and the heart-stage embryo were observed on the 28th day. Endosperms almost degenerated. In the TNS9 x A. batitzocoi treated with 100 and 150 ppm CA3, no fertilized ovules development was found at the 7th and 14th day, but sphearical embryos were observed at the 21st and 28th day after peg formation. No fertilized ovules was found to develop in other cross combinations.
|Appears in Collections:||農藝學系|
Show full item record
TAIR Related Article
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.