小麦抗穗发芽特性的研究

1986—1987年研究了16份小麦品种(系)的抗穗发芽特性。结果表明,不同品种收获前籽粒都可能出现最高发芽率(HGR)或穗发芽危险期(SDP),SDP的长短和出现时间及HGR的大小因品种而异;a淀粉酶只在籽粒临近成熟时才与穗发芽有关;颖壳的发芽抑制物和机械抑制力对籽粒吸水和穗发芽都有重要作用。据此,小麦抗穗发芽可分为三种型式,并且评价了各品种在抗穗发芽中的地位,以万县白麦子、江安油麦和巴州大白麦最抗穗发芽;库尔勒红冬麦、84—1155和81—5最不抗穗发芽。作者认为,选择颖壳中有较多发芽抑制物的材料是抗穗发芽育种的有效手段之一。

STUDIES ON PRE—HARVEST SPROUTING RESISTANCE CHARACTERISTICS IN WINTER WHEAT

Sixteen wheat cultivars (lines) grown in 1986—1987 crop season were evaluated for pre-harvest sprouting resistance characteristics of grain maturity, grain water uptake, Alpha-amylase and glumes. The results indicated that there were highest germination percentage (HGR) and sprouting dangerous period (SDP) in grain mature stage in all cultivars (lines). The length and time of SDP and the large of HGR had relation with cultivars. There was Alpha-amylase in early grain development, and only at late grain development was there correlation between Alpha-amylase activity and germination percentage. The effect of germination inhibitors and mechanical retard in glumes on water uptake of grain and germination were both important. The ways of sprouting resistance were divided in to three types according these charac-teristics. The status of cultivars in sprouting resistance was also evaluated, and 'Kuerllihongdongrnai', '84—1155', '81—5' are prone to sprouting while twang xianbaimaizi', 'Jianganyoumai', 'Bazhoudabaimai' are almost resistant. Selection for high levels of germination inbibitors and more powerful mechanical retard in glumes will be a valuable means of prolonging sprouting resistance in wheat.