Selection of a new early-ripening apple cultivar——'Huarui'

Abstract: ‘Huarui'is a new light red,high-quality,early-season apple(Malus×domestica Borkh)with excellent appearance. The original seedling derived from a cross between cultivar‘NY543'and‘Huaguan'in 1996 at experimental field in Zhengzhou Fruit Research Institute(ZFRI),Chinese Academy of Agricultural Sciences(CAAS). The seedling was planted in 1999 and bore fruits in 2002. It was initially selected in 2003 for its high fruit quality,big fruit size and very early ripening time. After two years continuous observation on the original tree,it was considered as a major clique. It was grafted on adult trees in experimental orchard in spring of 2006. From 2007 it began to be tested named‘Advanced Selection 3'in Henan,Shandong,Yunnan and Shanxi provinces,and to be tasted by farmers for evaluation. It was finally validated by the Henan Province Committee for Forest Variety Validation in 2014. The tree is vigorous with upright tree gesture. Young branches are red-brown with few pubescent; the average length of the annual shoots is 78 cm and the internodes is 2.6 cm. Leaves are acuminate,bi-serrated,10.2 cm long and 5.9 cm wide in average. Flowers are pink,petals are obovoid,white,distinct. Young trees mainly fruit on axillary flower bud,and two or three years later mainly fruit on short and middle bearing shoots. Fruits are slightly oblate to nearly round. Its average fruit height is 6.7 cm,average diameter is 8.3 cm,and fruit shape index is0.807. The fruits are slightly green-yellow with more than 70% blush,even full red. The skin is smooth,waxy,shiny,no rust,less powder with small grey white fruit spot. The flesh is ivory white,fine,crisp,juicy,with moderate sweet-sour flavor and pleasant aroma. The average fruit weight is 208 g,maximum fruit weight is 300 g. The quality is excellent,with 9.7kg·cm-2fruit firmness(without peel),13.2% soluble solids content,10.67% soluble sugar content,0.29% titratable acidity content,106.7 mg·kg^-1 vitamin C content. The fruit development period is 100-110 d and it matures at the end of July in Zhengzhou area. The number of inflorescence is 7,germination rate is 64%,and branching ability is 4 branches in average.Its fruit setting rate is high with a light physiological drop. In the orchard where the suitable pollinators are growing,the artificial pollination is not necessary as long as no natural weather disaster during blooming period. There is an example orchard where several matching cultivars were planted,when 40 d after blooming without being pollinated,the inflorescence fruit setting rate is 79.6%,the flower setting rate is 35.2%,the average number of fruit per inflorescence is 2.8,which are similar to them when 20 d after blooming. This variety can bear fruits second or third year after planted,has high yield potential. In‘Huarui'orchard,there are not serious powdery mildew,Marssonina apple blotches and bitter rot spreading in leaves. Its fruits can avoid anthracnose and ring rot because of early harvesting. But they are susceptible to beetle harm,when the fruits are ripening. The fruits can keep high firmness for 20 days under room temperature and 2-3 months under cold condition. It is suitable to be planted in‘Gala'growing area with high yield,such as Shaanxi,Shanxi,Henan,Hebei,Shandong,North of Jiangsu and Anhui,parts of Yunnan region,Linzhi area of Tibet and South of Xinjiang. Orchards should be built on neutral soil which has ability of moisture and fertilizer retention. When the seedlings are planted,enough organic fertilizer should be provided. If it is grafted on dwarf rootstock,the trees should be grown in rows of 1.5-2 m×3-4 m and trained in slender spindle type;if grafted on seedling Malus micromalus Borkh,in rows of 2.5-3.5 m×4-5 m and in free spindle type.‘Gala'‘NY543'‘Huashuo'‘Fujii',can be matched with‘Huarui'as pollinizer for each other,as their blooming time is close in most parts of China. Young trees trunk need be fixed if they were grafted on dwarf rootstocks,such as on M9 and M26. After germination,choose the strongest branch as central stem and keep its up-right growing,cut off or bend down the competitive branches. For winter pruning of first year,cut back center stem,and cut off spinding lateral branches,remain other lateral branches to promote flowering and fruiting. Young trees are inclined to sprout axillary flower buds; the excess axillary flower buds should be ticked off to avoid looting nutrients. Meanwhile,for adult trees,strict blossom and fruit thinning should be done. After leaves fall,a certain amount of organic fertilizer should be given. In the fruit expansion period,the nutrition should be replenished in time,especially calcium nutrition,and some attention should be paid to prevent sunburn.