南方甘薯新品种比较试验

以广薯87为对照,通过品比试验,分析了新近引进（选育）的福薯21、泉薯10号等9个南方甘薯新品种的产量、薯块品质、抗病性等性状,并评述了其在生产和育种上的利用价值：泉薯10号、福薯21、金薯2号可作为高产鲜食品种推广,桂粉3号和龙薯14宜作为优质高产品种推广。     

微量法快速提取甘薯叶DNA条件的优化

[目的]筛选出一种简便快捷的DNA微量提取方法。[方法]从不同处理甘薯植株的叶片中提取DNA样品并用紫外分光光度法和琼脂糖凝胶电泳法检测其纯度和质量。[结果]正常光照下甘薯植株的DNA产量最高,48h黑暗处理的次之,24h黑暗处理的最低。在正常光照下和48h黑暗处理中项芽的DNA产量都明显高于叶片;在24h黑暗处理中,顶芽与叶片的DNA产量比较接近。叶片DNA的纯度高于顶芽,正常光照下和24h黑暗处理中DNA的纯度高于48h黑暗处理中的。DNA电泳图谱表明,正常光照下叶片DNA的电泳条带一般比顶芽的好。48h黑暗处理中顶芽和叶片DNA的电泳条带没有很大差异。[结论]该试验为大批量实生苗DNA的快速提取和多种分子生物学研究奠定了实践基础。     

不同施磷量对鲜食型甘薯产量及磷素吸收的影响

采用田间试验的方法,设置了6个磷水平(0,37.5,75.0,112.5,150.0,187.5kg/hm²),研究不同施磷量对鲜食型甘薯产量、干物质积累和磷素积累的影响。结果表明,施磷能够显著增加甘薯产量并提高商品薯率,当施磷量为P205112.5kg/hm²时增产幅度最大。施磷水平对甘薯干物质积累与分配有显著影响,在甘薯各生长时期施磷条件下块根干物质积累量和积累速率整体上均显著高于不施磷处理(P<0.05),同时施磷还提高了地下部干物质分配比率,促进了块根产量的形成。施用磷肥可以显著提高甘薯对磷素的积累,随着施磷量的增加,甘薯植株的磷积累量呈现增加趋势。     

Impact of common sweetpotato viruses on total carotenoids and root yields of an orange-fleshed sweetpotato in Tanzania

The growing and consumption of orange-fleshed sweetpotato (OFSP) is considered as a mean to alleviate vitamin A deficiency in sub-Saharan Africa (SSA) region. However, majority of the field-tested OFSP varieties are susceptible to major diseases especially sweetpotato virus disease (SPVD), which is caused by co-infection of sweetpotato chlorotic stunt virus (SPCSV) with sweetpotato feathery mottle virus (SPFMV). A high beta-carotene content but susceptible variety Resisto was used in this study to evaluate the effects of SPVD on total carotenoids content and root yield. Compared with apparently healthy plants, reduction of 43, 16, and 37% of the total carotenoids content in the OFSP variety Resisto were observed in plants infected with SPCSV, SPFMV, and co-infection of both viruses. Storage root fresh weight was significantly (P < 0.001) reduced due to virus infection with high reduction recorded for SPFMV infection followed by co-infection of SPFMV with SPCSV. The same case was for sweetpotato vine length. However, no major reductions were observed in the vine weights. Co-infection of SPFMV with SPCSV caused more severe symptoms than single infections of the two viruses and each isolate caused distinct disease symptoms on the infected sweetpotato plants. In general, there was no direct correlation between sweetpotato virus disease symptom severity and reduction in total carotenoids. To our knowledge, this is the first report of the negative impact of SPCSV and SPFMV on the total carotenoid accumulation in OFSP varieties. Therefore follow up studies in the area of biochemical analysis should be initiated to gain knowledge on the impacts of SPVD on the biochemical pathways of carotenoid accumulation.     

离子束对甘薯胚性悬浮细胞团的辐射诱变效应

以甘薯品种栗子香为材料,用0～100 Gy 12C5+和0～200 Gy 4 He2+离子束分别照射其胚性悬浮细胞团,结果表明栗子香胚性细胞团适宜的12C5+和4He2+辐射剂量分别为30～50 Gy和50～70 Gy。对辐照后的材料进行培养,通过体细胞胚胎发生途径获得大量再生植株。将获得的再生植株移栽到大田,对其地上部和地下部特征进行分析,发现离     

甘薯体细胞胚状体及其在脱毒、扩繁中的应用

通过甘薯徐薯18茎尖体细胞培养诱导胚性愈伤组织和胚状体,建立了体细胞无性系.胚性愈伤和胚状体诱导培养基为MS附加0.5～2.0mg/L 2,4-D、0.5mg/L NAA、0.1mg/L BA及100mg/L HL.研究结果表明:采用茎尖体细胞胚胎发生途径能够同时实现试管苗的深度脱毒及大幅度提高扩繁量,脱病毒率达95%,扩繁量达382.9倍.田间种植该脱病毒种苗能     

不同产量水平甘薯品种光合产物分配差异及其原因

选取我国北方薯区主栽的食用型甘薯品种龙薯9号、红香蕉、泰中6号、苏薯8号、遗字138和北京553,于2011—2012年2个生长季在山东农业大学农学试验站进行大田试验,研究不同产量水平甘薯品种光合产物的分配差异及其原因。在甘薯主要生长时期测定茎蔓各部位蔗糖含量和基部茎粗、在块根膨大过程中对功能叶进行13C标记,探索不同品种13C同化物分配特点,同时研究上述项目与收获指数和块根产量的关系。结果表明,高产品种龙薯9号、红香蕉、泰中6号和苏薯8号产块根均在60 t hm–2左右,而中、低产品种遗字138和北京553产块根在50 t hm–2以下。高产品种的收获指数显著高于中、低产品种。在块根膨大前期高产品种的块根成为光合产物的分配中心,而中、低产品种的块根则在块根膨大后期成为分配中心;在块根膨大前、中期,高产品种13C同化物在块根中的分配比例显著高于中、低产品种,即高产品种光合产物由功能叶向块根的转运能力强于中、低产品种。供试品种茎蔓基部的蔗糖含量均高于顶部,且中、低产品种的蔗糖浓度差大于高产品种;随着甘薯生长发育,中、低产品种茎蔓基部增粗速率高于高产品种。相关分析表明,块根产量与收获指数呈极显著正相关(r=0.98**,2011;r=0.93**,2012);块根13C分配率与块根产量和收获指数均呈显著正相关(0.87*和0.91**,2011;0.92**和0.99**,2012);生长中后期,基部茎粗与块根产量和收获指数均呈显著负相关(–0.78*和–0.83*;–0.88**和–0.95**)。块根成为光合产物分配中心的时间早、光合产物由功能叶向块根的转运能力强是高产品种收获指数显著提高的主要原因,而中、低产品种光合产物由叶片向块根转运能力差的主要原因是块根中光合产物卸载不畅。     

Variation in Gelatinization Characteristics of Storage Root Starch During Sweetpotato Growth and Development

The differential scanning calorimetry (DSC) and rapid visco-analyzer (RVA) were used to determine the starch gelatinization characteristics during the growth of three sweetpotato cultivars. The results showed that the starch contents of three sweetpotato cultivars all decreased as growth progressed. Changes of the amylose contents differing in harvesting dates should be discriminated according to the cultivars. At the early harvests amylose contents of Xushul8 and Zheda9201were relatively high, but those of Zhe3449 were low. As the growth duration of sweetpotatoes prolonged, the peaks of DSC thermograms tended to occur at a low temperature and not to be so obstrusive with the increased width of the peak.Obvious decreases were observed, values of onset, peak and conclusion temperatures, as well as enthalpy of phase transitions, as growth time lengthened. The peak viscosities, as determined through RVA, showed a rising tendency as growth progressed. In addition, statistical analysis revealed that there were correlations between the amylose content and gelatinization characteristics to some extent, which were affected by genotypes evidently.     

甘薯花青素的提取及其抑菌效果分析

 建立了甘薯块根花青素（sweetpotato anthocyanin,SPAC）的大孔树脂吸附制备技术，分析了其抑菌作用和机理。结果表明，在0.8%柠檬酸、物料比1∶200，60℃温水浴提取2 h的条件下可获得最大的提取率3.81 mg·g-1。 粗提物经AB-8大孔树脂过柱纯化后可获得色价为225.1E的纯品，色价提高6倍。研究发现SPAC对3种常见致病菌均有抑菌作用，并与其浓度呈正相关。通过电镜观察、SDS-PAGE分析及生长曲线比较表明，SPAC抑菌机理是通过SPAC与细胞中的蛋白或酶结合，使其变性失活，抑制对数生长期的细胞分裂，而后使细胞质固缩、解体，导致细胞死亡。SPAC具有色素和抑菌双重功能，是理想的功能性天然色素。     

Enlargement of the variances in amount and composition of anthocyanin pigments in sweetpotato storage roots and their effect on the differences in DPPH radical-scavenging activity

To investigate the effect of differences in anthocyanin composition on radical-scavenging activity in the purple-fleshed sweetpotato storage root, 124 sweetpotato clones with various compositions of anthocyanin were produced by crosses among superior sweetpotato genetic resources, and were analyzed for anthocyanin composition and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity (RSA). The highest content of anthocyanin among the clones was twofold higher than the content of cv. Ayamurasaki, which has been released for use in industrial pigment production in Japan. The range of variance in anthocyanin composition was very wide, as the ratio of peak areas of cyanidin-based anthocyanins to total anthocyanin peak areas ranged from 85.7% to 6.0%. The relationship between anthocyanin content and RSA was positively correlated. Correlation coefficients between RSA and the HPLC peak areas of cyanidin-based anthocyanins ranged from 0.606 to 0.687, whereas those of peonidin-based anthocyanins were 0.124–0.271. These results clearly demonstrated that cyanidin-based anthocyanins are closely related to DPPH RSA in sweetpotato storage roots.