大豆種間雜交與雜交胚及胚乳發育之研究

Abstract

以栽培種大豆（G. max）與Glycine亞屬之野生種G. tomentella, G. dolichocarpa, G. tabacina, G. latifolia, G. canescens, G. falcata等8種19系統為材料，進行栽培種與野生種之種間雜交，調查正、反雜交的成功率，並利用石蠟切片，行組織學觀察不同物種大豆之自交及種問雜交後胚及胚乳之發育，結果如下。 以G. max為母本，野生種大豆為父本，5天內不落莢之正交成功率為9.4%（468/4,972)；反交之成功率為4.3%(55/l,289)：正交組合中，栽培種與野生種大豆雜交均無法獲得雜交種子，且雜交莢在授粉後25天左右掉落。 大豆不同物種自交胚及胚乳之發育，除胚乳均屬核型胚乳外，胚的發育期相當不一致，發育最快者為G. tabacina (Ta18)，其次依序為G. latifolia (La2), G. canescens (Cal), G. max (KS10),及G. tomentella (To12)，最慢為G. dolichocarpa(Do3)。其發育至子葉期的時間分別為10、12、13、17及18天。 種間雜交胚及胚乳發育切片結果，所有組合胚乳均較胚提前敗育，各正反組合11-16天胚乳開始出現敗育，而18-24天胚組織呈敗育現象。 Interspecific reciprocal crosses were made between G. max and G. tomentella, G. dolichocarpa, G. tabacina, G. latifolia, G. canescens, G. falcata of the subgenus Glycine. The successful rates of reciprocal crosses were investigated. Further,the developmental characteristics of embryo and endosperm of selfed and interspecific cross in Glycine species using paraffin section were also examined. The results were summarized as follows. When G. max cv. KS1O was used as female parent, 468 hybrid pods were obtained. The successful rate of cross and reciprocal cross were 9.4% (468/4,972) and 4.3% (55/1289), respectively. The poding period could be over 25 days, no hybrid seed was harvested. Observation of the developmental characteristics of embryo and endosperm of Glycine species showed that the endosperm belonged to a nuclear type. However, the embryo development was unequal among species, G. tabacina (Ta18) showned the fastest, followed by G. latifolia (La2), G. canescens (Cal), G. max(KS1O), and G. tomentella (To12), and G. dolichocarpa(Do3) was the slowest. The durations of embryo development into the cotyledon- stage for the above species were, in order, 10, 12, 13, 17 and 18 days. Observation made on the developmental characteristics of embryo and endosperm between of the interspecific crosses in Glycine species showed that the abortion of endosperm was faster than that of embryo in all combinations. In cross and reciprocal cross combinations, abortion occurred at 11-16 days and 18-24 days for endosperm and embryo, respectovely.