Selective Breeding Of Chestnut (Castanea Mollissima Blume) New Cultivars With Different Mature Stage

Chestnu（tCastanea mollissima Blume）originated in mainland China, and it is one of theearliest fruit trees for the cultivation and utilization. Shandong province as the famous fryingchestnut production area has become one of the largest domestic production areas along theSouth of Tai-Yi mountain range. Due to the complex habitat factors, long-term naturalselection and seedling selection, Shandong production area reserves plentiful genetic diversityof chestnuts, including high-quality, high-yield and stress-resistant germplasm, etc., whichprovide the excellent germplasm resources for breeding and cultivation. Though someprogress had been made in the chestnut breeding research in our country, some problems arestill obvious, including the relative concentration of fruit maturity, lack of the early-maturityvarieties and medium-grain type frying varieties, etc.. In this study,’Dongyue Zaofeng’,’Dongwang Mingli’,’Red chestnut No.2’ and ’Daiyue Zaofeng’ had been bred by seedlingbreeding from a large number of seedling trees of Taishan chestnuts. A comparative study onbiological characteristics has been done between these four new chestnut varieties and ’LuyueZaofeng’,’Huangpeng’ selected before. A high quality cultivation technique system has beenestablished. The main conclusions of the study are as follows:1. The market demand of the Shandong chestnut producing areas was surveyed and a standardof variety breeding was formulated. According to the market demand, market prices, and theproblems of concentrated mature stage, lacking the early-maturity varieties and medium-graintype frying varieties, a standard of variety breeding has been formulated, including maturitymatching (the early maturity varieties mature in late August), single nut weight more than10g, bright and beautiful appearance, sugar content of dry sample more than20%, nut ratemore than45%, empty Involucres rate less than5%, early fruiting and high yield, strongresistance, and storability.2. Four new chestnut varieties had been bred from a lot of big seedling trees of Taishanchestnut in Huangqian, Mata of Taian and in Loude of Xintai, including ’Dongyue Zaofeng’,’Dongwang Mingli’,’Red chestnut No.2’ and ’Daiyue Zaofeng’. All of them have been examined and approved by the Variety Certification Commission of Shandong province.3. These six varieties have the characteristics of early fruiting, high quality, high yield andsingle nut weight more than10g, which are belonging to the medium-grain type fryingvarieties and corresponding with the current market demand. Among all these varieties,’Luyue Zaofeng’,’Dongyue Zaofeng’ and ’Daiyue Zaofeng’ mature in late August in Tai’an,Shandong province, and enrich the germplasm resources of the early maturity frying chestnuts.’Huangpeng’, maturing in early September, belongs to middle maturing variety.’DongwangMingli’ and ’Red chestnut No.2’ mature from mid-September to late, and belong to mid-latematuring variety. The six chestnut varieties have the different mature time, and hence extendthe time of chestnut harvest and market. In addition, the ’Red Chestnut No.2’ is also animportant ornamental fruit.4. By evaluating the biological characteristics and combining the conventional managementtechniques and modern chestnut cultivation technology, a high-quality and efficientcultivation techniques has been studied and realized the supporting between varieties andcultivation techniques. From the cultivation test, we find that the yield of these six varietiesused this supporting cultivation techniques is about250kg per666.7m2in full bearing periodafter5years, and, in particularly, the yield of ’Dongyue Zaofeng’,’Huangpeng’, and ’Redchestnut No.2’ are more than300Kg per666.7m2. The high quality and efficient cultivationtechnique system was formed and had been demonstrated and popularized in Tai’an, Jinan,Rizhao, Linyi, Laiwu of Shandong province, Hebei province and Beijing, etc.. These newvarieties and cultivation techniques have been accepted by farmers and generated a significantbenefit for economy, society and ecology.