为了解决五倍子单宁酸工业生产中提取得率较低和溶剂残留等问题,以五倍子为原料,通过辐照剂量、提取温度、提取时间、料液比的单因素试验和正交试验,优化筛选辐照预处理辅助提取五倍子单宁酸的工艺技术.结果表明:辐照预处理辅助提取五倍子单宁酸的影响因素大小次序为提取温度＞辐照剂量＞提取时间＞料液比,其中提取温度影响显著;最优工艺技术参数为辐照剂量800 kGy、浸提温度90℃、料液比1:35、浸提时间4.5 h,在该参数条件下,单宁酸提取得率可达65.13％,纯度可达81.36％;与常规水提取法、溶剂提取法相比,辐照预处理辅助提取五倍子单宁酸的得率分别提高了15.13％和20.13％.

Kumquat is conducive to the studies of flower and fruit traits,and related gene expression in the flower and fruit using genetic transformation since juvenile period is short and may blossom many times per year,but the rate of seedling regeneration in kumquat still needs to be improved.This study used internode stem segments of‘Yangshuo’ Kumquat(Fortunella spp.Swingle) in Guangxi as the materials.When using the seed-lings cultured in darkness for 25 days and light for 10 days as explants and MS+3 mg/L 6-BA as regeneration culture medium to grow about 50 days, the adventitious bud regeneration rate could exceed 80%. And after agrobacterium infection,using co-cultivation medium( MS + 2 mg/L 6-BA + 1 mg/L NAA + 1 mg/L KT) and selection medium(MS + 3 mg/L 6-BA+ 50 mg/L Kanamycin) as culture conditions,13.3% resistant shoot regeneration rate was obtained.The buds were cut down from the explants and placed in the rooting medi-um (1/2 MS+3 mg/L IBA+1 g/L activated carbon) 86%of the rooting rate was obtained.Finally,the research established an effective regeneration system by studying the various factors affecting regeneration frequency of adventitious shoots and resistant shoots.

澧县位于湖南省西北部,洞庭湖西岸,因澧水贯穿全境而得名,是湘西北通往鄂、渝、川、黔的重镇,素称九澧门户.全县辖32个乡镇,总面积2107平方公里,总人口92万,农户21万户,农业人口占全县总人口的70％.澧县是一个典型的农业大县,但农业在GDP中占比不到三分之一,农业发展空间很大.长期以来农村金融服务缺失,农户缺乏有效抵押担保物,加上银农信息不对称,农民贷款难,已成为制约农村经济发展的瓶颈,至2013年末涉农贷款占全县整个贷款余额不到9％,涉农金融机构对农民贷款投入少,金融支农工作潜力大、任务重.为加快推进农村经济发展,改善农村信用环境,该县结合全国丽水工作会议精神和上级工作要求,采取“政府主导、人行推动、多方参与、共同受益”的模式,积极构建农户信息平台,着力推广小额农户信用贷款业务,把农村信用体系建设作为破解金融支持三农发展的有效途径.

To increase the genetic transformation efficiency of sweet orange infected by Agrobacterium,an explant derived from internode stem segments of sucarri orange seedling was adopted to optimize light regimes and co-cultivation condition for the growth.Meantime,seedless gene was transferred to succari orange.The results revealed that explant from seedling had higher regeneration and transformation rate under the condition of cultured 20 d in darkness first and then exposed 10 d in lighting environment.Acetosyringone(AS) concentration was a key factor impacting transformation rate,and the optimal performance of transformation was under 20 mg/L concentration of co-cultivated medium with a temperature 19 ℃ and pH 5.4–5.7.The positive rate could reach 29.4% through the analysis of GUS staining,which were further proved by PCR analysis that the foreign gene was indeed integrated into the host genome.

Using epicotyls of kumquat(Fortunella crassifolia Swingle)seedlings growing in vitro as explants,an efficient regeneration system was established.The results show that,using 35-day-old epicotyl segments of kumquat,and based on the culture media of MS+6-BA 2.0 mg/L+NAA 1.0 mg/L+KT 1.0 mg/L+sucrose 3%+agar 0.8%(pH5.7)in the tempreture of 26℃ for a 16/8 h light/dark cycle and without dark-culture,adventitious shoots regenerated from 90%of the epicotyl explants.

A parthenocarpy gene (DefH9-iaaM) was introduced into Succari to obtain possible seedless transformants, by using internodal stem segments as explants to establish an efficient regeneration and transgenic system. The results indicated that 30-day-old seedlings were the most efficient explants. The co-culture in darkness for 3～6 days gave a rise to good regeneration. The optimum medium for adventitious buds regeneration was MS+6-BA 5.0 mg/L. And MS medium supplied with 6-BA1.0 mg/L and NAA0.1 mg/L showed the highest bud multiplication rate,3.3 buds on each internodal segments. The shoots successfully rooted after 20 days in 0.5 mg/L NAA. After Agrobacterium-mediated transformation,6 transgenic plants out of 17 regenerants were identified by PCR.

Genetic transformation systems from mature tissue of citrus have to be achieved as a necessary requirement for the introduction of useful genes into specific cultivars and the rapid evaluation of the genetically modified characteristic.This research presents a protocol for in vitro regeneration and genetic transformation of C.sinensis Osbesk cv Newhall using as explants internodal segments from adult plants maintained in the greenhouse.The contamination rate of the pretreated disinfection method was the lowest.Adventitious buds induction for C.sinensis Osbesk cv Newhall was the most effective on MS medium supplemented with 3 mg/L 6-BA.chit42 gene was introduced to the C.sinensis Osbesk cv Newhall by Agrobacterium-mediated.Adventitious buds were micro-grafted onto seedlings of Carrizo citrange grown in vitro and one month later re-grafted on greenhouse-grown rootstocks.By PCR detection,we obtained 2 transformed plants,RT-PCR analysis indicated that the transgene chit42 regularly expressed in the transgenic plant.