不结球白菜抗病育种的研究 Ⅶ.矮抗四号新品种的选育

Studies on breeding for disease resistance in nonheading Chinese cabbage Ⅶ. Breeding of a new varietyDwarf Resistant No.4

１９９１～１９９４年在抗芜菁花叶病毒（ＴｕＭＶ）和霜霉病研究工作的基础上，利用杂种优势育种技术，以抗病矮脚黄雄性不育两用系为母本，以９３Ｒ－３７（自交系）为父本，选育出综合性状优良的矮抗四号三抗新品种。其特点：（１）丰产：夏季、秋季生产试验平均产量分别达４２．２和６３．４ｔ／ｈｍ２，比对照矮杂一号和矮抗一号分别增产２２．９％和２５．１％；（２）抗病：ＴｕＭＶ、霜霉病、黑斑病人工鉴定病情指数分别为１．８５（ＨＲ），１５．４８（Ｒ）和１０．１０（ＨＲ）；（３）优质：Ｖｃ含量比对照提高５．２％，有机酸含量低于对照，叶片和叶柄可溶性固形物含量均高于对照矮抗一号；（４）耐热：热害指数低（９．７５），比对照矮杂一号（４２．５０）降低了３３５％；叶片厚为０．５５ｍｍ，是对照的１．４９倍。

On the basis of the previous work on TuMV and downy mildewresistant breeding during 19911994, a new variety Dwarf Resistant No. 4 of Brassica campestris ssp. chinensis Makino was bred by means of crossbreeding with Aijiaohuang genetic male sterility as maternal and 93R37 (inbreed line) as paternal. The main characteristics of the new variety were as follows. (1)High yield: the average yields in summer and autumn were 42.2 t and 63.4 t per hectare respectively, 22.9% and 25.1% higher than the check cultivar Dwarf Hybrid No. 1 and Dwarf Resistant No. 1. (2) Disease resistance: values of disease index under artificial conditions for TuMV, downy mildew and alternaria leaf spot were 1.85(HR), 15.48(R), 10.10(HR) respectively. (3) Good quality: content of vitamine C was 5.2% higher than the check cultivar. Content of organic acid was lower than that of the check. Soluble solid substances in blade and petiole were higher than that of the check Dwarf Resistant No.1. (4) Heat tolerance: high temperature injury index was 9.75, 335% lower than that of the check. Thickness of leaf was 0.55 mm, 1.49 times as much as that of Dwarf Hybrid No.1