Detailed Introduction to Two Varieties of Kunlun Tianxing Apricot

**The Second Ranch of Yecheng under the Third Agricultural Division of the Construction Corps is located 60 km south of Yecheng County on the northern slope of the Kunlun Mountains, at 76°30" to 77°35" E and 36°40" to 37°30" N, with an average altitude of 2200 to 4850 m, and has a warm temperate continental climate. The average annual temperature is 5 to 8°C, the highest temperature is 36°C, the lowest temperature is -25°C, the effective accumulated temperature is 2800 to 3200°C, the annual precipitation is 80 to 200 mm, the annual evaporation is 1000 to 1800 mm, and the annual sunshine is 2990 hours. The frost-free period is about 125 days.

Because of the special climate, economic crops such as cotton cannot grow and develop normally here. But for apricots, low accumulated temperature delays the fruit ripening period, and the large temperature difference between day and night is favorable for sugar accumulation. The flowering period is 15 to 25 days later than on the plains, and the fruit ripening period is 1 to 2 months later, so fresh apricots can still be eaten by National Day; the apricot fruit is large, juicy, brightly colored and sweet. Its fruit is also an excellent product for drying, and the dried apricots produced have thick flesh and good taste. There are many local apricot varieties, collectively called Kunlun Tianxing apricot.

The Second Ranch of Yecheng began vigorously developing Tianxing apricot cultivation in 2000. At present, the cultivated area has reached 800 hm2, with 133 hm2 of fruiting trees, and the varieties have also been screened from the initial 5 to 6 down to 2: Dahong apricot and Heiye apricot.

The Dahong apricot fruit is round, with a smooth, deep red skin, and an average single fruit weight of 24.649; it is juicy and sweet, and especially suitable for fresh eating. The soluble solids content is 12.73%, and the total sugar, total acid and vitamin C contents are 6.65%, 1.89% and 32.03 mg/g respectively. The first flowering date is April 15, the full flowering period is April 18 to 21, the petal-fall period is April 22 to 26, the first fruit enlargement period is April 26 to May 21, the pit-hardening period is May 21 to June 11, and the ripening period is July 5.

The Heiye apricot fruit surface is smooth, yellow with a slight red blush, and the average single fruit weight is 24.28 g; it has abundant juice and high sugar content. The soluble solids content is 14.75%, and the total sugar, total acid and vitamin C contents are 7.58%, 0.95% and 15.71 mg/g respectively. The drying rate is as high as 38.78%, making it a fine variety for drying. The dried apricots produced have thick flesh and a sweet taste. The first flowering date is April 10, the full flowering period is April 15 to 18, the petal-fall period is April 18 to 22, the first fruit enlargement period is April 22 to May 10, the pit-hardening period is May 10 to June 10, and the ripening period is July 10.