Green Treasure Choy Sum

Green Treasure Choy Sum

　　Variety Name: Green Treasure 70-Day Choy Sum

　　Approval Number: Yue Shen Cai 2003005

　　Breeding Unit: Guangzhou Vegetable Research Institute

　　Variety Source: Systematically bred from variant plants of Chi Xin No. 2

　　Characteristics: Conventional variety, medium-late maturing, 42 days from sowing to initial harvest, with an additional 10 days for extended harvesting, mainly harvesting main shoots; vigorous growth, relatively short and compact plant type, plant height 32 cm, basal leaves are willow-leaf shaped, dark green, smooth leaf surface, medium size, 21.8 cm long and 8.6 cm wide, petiole 9.7 cm long and 1.7 cm wide; shoot leaves are willow-leaf shaped, bluish-green, tightly formed, even and glossy, main shoot height 27.3 cm, diameter 1.55 cm, weighing about 41.3 grams. Strong branching ability, high purity, uniform flowering, high commercial rate, sweet taste, low fiber content, excellent quality. Resistant to viral diseases, and relatively resistant to downy mildew.

　　Yield Performance: In autumn trials in Guangzhou during 2001 and 2002, yields were 799.9 kg and 810.8 kg per mu respectively. In 2001, yield increased by 22.1% compared to the control variety 70-Day Te Qing, while in 2002 it decreased by 2.9%. The average yield over two years was 805.4 kg per mu, an 8.1% increase over 70-Day Te Qing.

　　Key Cultivation Techniques: (1) In South China, suitable sowing periods are from September to November and from late February to March. Can be directly sown or transplanted from seedlings. Direct sowing requires 350–400 g of seeds per mu, transplanting from seedlings requires 18–20 days of seedling stage; (2) Apply sufficient base fertilizer, timely top-dressing during growth. Early top-dressing should mainly use quick-acting nitrogen fertilizers, supplemented by phosphorus and potassium fertilizers in the mid to late stages to improve shoot yield and quality; (3) Pay attention to controlling flea beetles (Phyllotreta striolata) during the seedling stage, and control small cabbage moth and cabbage looper in the mid to late stages.

　　Provincial Variety Approval Committee Opinion: Green Treasure 70-Day Choy Sum is a conventional variety, medium-late maturing, mainly harvesting main shoots, vigorous growth, relatively short plant type, shoot leaves are tightly formed, even and glossy, good yield potential, high commercial rate, sweet taste, low fiber, excellent quality. Resistant to viral diseases and relatively resistant to downy mildew. It has good commercial and yield performance, strong adaptability and stress resistance. Suitable for spring and autumn cultivation across the province. Meets the crop variety approval standards of Guangdong Province and is hereby approved.