普通小麦与鸭茅状摩擦禾的远缘杂交──Ⅰ．胚形成频率

Wide Hybridization Between Triticum aestivum and Tripsacum dactyloides Ⅰ.Frequency of Embryo Formation

本文在国内首次报道普通小麦（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍ，２ｎ＝６ｘ＝４２）和鸭茅状摩擦禾（Ｔｒｉｐｓａｃｕｍｄａｃｔｙｌｏｉｄｅｓ，２ｎ＝４ｘ＝７２）杂交成功。用３３个春小麦品种（系）为母本，与鸭茅状摩擦禾杂交，授粉６６３６朵花，获得３０８３个颖果。颖果分为有胚和无胚两类。有胚颖果８０６个，占总颖果数的２６．１４％。３３个母本中３０个都能和鸭茅状摩擦禾杂交，１４个母本的杂交亲和性（胚数／授粉花数×１００）超过１０％。４个最高的分别达到５９．００％，３９．００％，２９．５０％和２２．６６％与小麦和玉米（Ｚｅａｍａｙｓ，２ｎ＝２ｘ＝２０）的杂交相比，鸭茅状摩擦禾同样对小麦Ｋｒ基因的作用不敏感，且与小麦的杂交亲和性要比与玉米杂交时高。加之鸭茅状摩擦禾为野生型，具有多年生、多分枝、花期长等特点，可以克服小麦和玉米杂交时花期不遇的困难。讨论了用它作为花粉给体的优越性及在小麦改良和产生小麦单倍体上的前景。

This paper reports a successful hybridization between wheat(Triticum aestivum2n=6x=42)and Tripsacum dactyloides,(2n=4x=72). Thirty-three genotypes of wheat were used as female parents in the crosses with Tripsacum dactyloides.3083 caryopses were obtained from 6636 pollinated florets. The caryopses did not always contain embryos . 806 embryos were cut out with 26.14% of caryopses from 30 of 33 wheat varieties(lines).The individual crossability(the percentage of embryo formation)of 14 female parents were over 10%, 4 of which produced embryos at frequencies of59.00%, 39.00%, 29.50%and 22.66%,respectively. As compared with maize, Tripsacum dactyloides appears not only relatively insensitive to the action of the Kr loci but also higher frequency of embryo formation. Considering that Tripsacum dactyloides has wild genotype characteristics, such as perennial, more tillers, prolific pollen,longer flowering and higher resistance to adversities(disease, insect pest, cold drought et al .)the potentiality of wheat×Tripsacum dactyloides crosses for wheat improvement and for wheat haploid production is discussed.