3种处理剂对贮藏甘薯的保鲜效果

为研究1-甲基环丙烯(1-MCP)、水杨酸(SA)、草木灰浸出液对甘薯贮藏的影响,使用不同浓度1-MCP、SA、草木灰浸出液处理薯块,测定贮藏期间相关品质及酶活性,评价甘薯的贮藏效果.结果表明:1.0μL/L 1-MCP处理和0.10 g/L SA处理能有效减缓贮藏薯块中可溶性糖、淀粉、可溶性蛋白、Vc含量的下降,并保...     

新型香蕉果实贮藏保鲜处理剂--1-MCP

香蕉果实为呼吸跃变型果实,采后5～8天自然后熟,极易发生腐烂;若经外源乙烯处理,果实能够迅速后熟,色,香、味俱佳,但货架期短,很快便失去食用和商品价值。     

甘薯保鲜贮藏技术小结

甘薯是无性繁殖的粮食作物。自古以来就有薯种贮藏方法。落实生产责任制、土地联产承包以后，粮食连年增产，在我县吃地瓜米的人没有了，甘薯只充当饲料，近年来随着土地承包经营的流转，大量农村劳动力转移。而甘薯由于有补虚、益气、健脾、强肾等功能，     

低温贮藏下两种甘薯的品质变化研究

研究了甘薯品种宁紫1号和宁选1号在6~7℃、相对湿度85%~90%条件下贮藏105 d期间的品质变化。结果表明:低温贮藏能较好的保持两种甘薯的总淀粉、可溶性蛋白质和黄酮甙含量,但低温下两种甘薯的累计腐烂率均较高。另外,宁选1号在6~7℃低温下的贮藏品质总体上优于宁紫1号。     

不同贮藏温度对甘薯品质的影响

为明确贮藏温度对甘薯品质的影响,以甘薯品种‘心香’为试验材料,研究了贮藏温度（8,12,15,20,22℃）对甘薯食味品质、可溶性总糖、可溶性固形物、失重率、腐烂率、发霉率和发芽率的影响。结果表明：8℃贮藏可以显著提高甘薯贮藏前期食味品质及可溶性总糖含量,但甘薯易受冷害,贮藏后期腐烂率较高;12℃贮藏可以显著降低甘薯失重率和腐烂率,且贮藏84 d内无发芽、发霉现象;15℃甘薯发霉率、20℃发芽率显著高于其他处理,22℃易使薯块失水萎蔫,均不利于甘薯的保鲜。综合来看,短期贮藏（28 d内）时,8℃贮藏可以较快提高甘薯食味品质;长期贮藏时（84 d内）,12℃贮藏效果最好。     

两种甘薯在中后期贮藏期间的品质变化研究

研究了黄心甘薯和白心甘薯在室温(7～22℃),相对湿度80%～88%条件下贮藏60～165 d期间的品质变化。结果表明:室温贮藏下甘薯的腐烂率和失重率逐渐增加;含水量、可溶性蛋白质、可溶性总糖、总淀粉总体呈下降趋势;明度、红度和黄度较为稳定,α-淀粉酶、β-淀粉酶和总淀粉酶活性呈波动起伏状态。总的看来,两种甘薯的腐烂快速上升期出现在贮藏120～135 d期间,营养劣变加速期出现在贮藏120～135 d后,淀粉酶活高点期出现在贮藏105 d后。此外,白心甘薯在室温下的贮藏品质总体上明显优于黄心甘薯。     

1-MCP处理MA贮藏对采后香梨贮藏品质的影响

以新疆库尔勒香梨(Pyrus sinkiangensis Yu)为试材,研究1-甲基环丙烯(1-MCP)处理后MA贮藏对采后果实呼吸速率、乙烯产生、可溶性固形物(SSC)含量、硬度、果皮色调角变化的影响.结果表明:1-MCP结合MA贮藏明显降低了香梨果实的呼吸速率,显著抑制果实乙烯的产生,推迟乙烯高峰的出现;处理果实保持了较高的SSC,抑制果实硬度的下降,减缓果皮色调角的下降.在货架期,1-MCP明显抑制果皮色调角的下降,保持果实品质.     

Regulation of Anthocyanin during Storage Root Development Stage in Sweet Potato(Ipomoea batatas(L.) Lam.)

Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic genes by semi-quantitative RT-PCR. Anthocyanin concentration in sweet potato cvs Jishu 18 and Ayamurasaki increased steadily during storage root development stage. The accumulation rate in two genotypes peaked at 50 to 65 d after transplanting, and then declined rapidly. During storage root development of Ayamurasaki, the anthocyanin biosynthesis gene, IbCHS, was constitutively expressed, the genes IbF3H, IbDFR, IbANS were induced steadily, reaching a maximum at the later stage of root thickening, and IbPAL steadily decreased. Therefore, the mechanism of anthocyanin accumulation differed between the two cultivars, and anthocyanin biosynthesis was regulated through regulation of its synthetic enzymes.     

Postharvest Quality and Physiological Behavior of Sweet Potato （Ipomoea batatas Lam.） Leaf Stalks Under Three Temperatures

Sweet potato （Ipomoea batatas Lam.） leaf stalks were cut into 20 cm length, and stored at 20, 6, and 2℃. The respiration rate, ethylene production, ascorbic acid, free amino acid, total chlorophyll content, freshness, and shelf life were determined during storage to investigate the effect of storage temperatures on the quality and physiological responses in sweet potato leaf stalks. Wound responses were observed as high respiration rate and ethylene production immediately after cutting. Sweet potato leaf stalks were found to be sensitive to chilling injury manifested as browning and water-soaking on the surface at 2℃. In contrast, sweet potato leaf stalks were susceptible to senescence, exhibited by etiolating and yellowing, at 20℃. Loss in weight and chlorophyll was minimized under low temperatures. High temperatures also caused the accumulation of amino acids with a significant loss of ascorbic acid and chlorophyll. Sweet potato leaf stalks had a storage life of 16 days at 6℃, 8 days at 2℃, and 6 days at 20℃, respectively.     

Cloning and Analysis of NBS-LRR Type Resistance Gene Analogues in Sweet Potato ( Ipomoea batatas)

The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disense-resistance genes. A fragment of about 500 bp was amplified from genomic DNA of sweet potato using the specifically designed degenerate primers. After cloning and sequencing, 20 NBS-LRR type of disoase-resistance gene analogue (RGAs) in sweet potato were observed. The deduced amino acid sequence of DNA fragment contains the conserved motifs of NBS-LRR type RGAs, such as P-loop, Kinase-2α, Kinase-3α and GLPL domain. The 20 RGAs could be sorted into two subclasses, namely TIR-NBS-LRR type and non-TIR-NBS-LRR type. Compared with the known resistance genes including N, L6 and M, the percentages of homologous amino acid sequence in 10 TIR-NBS-LRR range between 21% -44%. While other 10 non-TIR-NBS-LRR assume 15% -46% homology with the known resistance genes (Prf, RPM1, RPS2, etc.). Consequently the RGAs may further be used as molecular marker for screening the candidate disease-resistauce genes in sweet potato.     

甘薯中NBS-LRR类抗病基因同源序列的克隆及序列分析

以高抗根腐病的“徐薯18”总DNA为模板进行PCR扩增,获得其抗病基因同源序列RGAs,对其氨基酸序列进行聚类分析和同源性比较分析,为进一步在甘薯中克隆R基因奠定基础。     

Cloning and Analysis of NBS-LRR Type Resistance Gene Analogues in Sweet Potato (Ipomoea batatas)

The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disease-resistance genes. A fragment of about 500 bp was amplified from genomic DNA of sweet potato using the specifically designed degenerate primers. After cloning and sequencing,20 NBS-LRR type of disease-resistance gene analogue (RGAs) in sweet potato were observed. The deduced amino acid sequence of DNA fragment contains the conserved motifs of NBS-LRR type RGAs,such as P-loop,Kinase-2α,Kinase-3α and GLPL domain. The 20 RGAs could be sorted into two subclasses,namely TIR-NBS-LRR type and non-TIR-NBS-LRR type. Compared with the known resistance genes including N,L6 and M,the percentages of homologous amino acid sequence in 10 TIR-NBS-LRR range between 21%-44%. While other 10 non-TIR-NBS-LRR assume 15%-46% homology with the known resistance genes (Prf,RPM1,RPS2,etc.). Consequently the RGAs may further be used as molecular marker for screening the candidate disease-resistance genes in sweet potato.     

甘薯中NBS-LRR类抗病基因同源序列的克隆及序列分析(英文)

The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disease-resistance genes. A fragment of about 500 bp was amplified from genomic DNA of sweet potato using the specifically designed degenerate primers. After cloning and sequencing,20 NBS-LRR type of disease-resistance gene analogue (RGAs) in sweet potato were observed. The deduced amino acid sequence of DNA fragment contains the conserved motifs of NBS-LRR type RGAs,such as P-loop,Kinase-2α,Kinase-3α and GLPL domain. The 20 RGAs could be sorted into two subclasses,namely TIR-NBS-LRR type and non-TIR-NBS-LRR type. Compared with the known resistance genes including N,L6 and M,the percentages of homologous amino acid sequence in 10 TIR-NBS-LRR range between 21%-44%. While other 10 non-TIR-NBS-LRR assume 15%-46% homology with the known resistance genes (Prf,RPM1,RPS2,etc.). Consequently the RGAs may further be used as molecular marker for screening the candidate disease-resistance genes in sweet potato.     

甘薯中NBS-LRR类抗病基因同源序列的克隆及序列分析

根据已知的NBS-LRR类抗病基因蛋白质的保守序列设计简并引物,用以扩增甘薯基因组中的抗病基因同源序列,获得一条大小约500 bp的扩增片段,克隆测序后得到20个NBS-LRR类抗病基因同源片段RGAS。其推导的氨基酸序列均具有P-loop、Kinase-2a和Kinase-3a及GLPL区等几个保守区,并且可分为TIR-NBS-LRR和non-TIR-NBS-LRR两个亚类。其中10个TIR亚类RGAS与已克隆的N、L6、M等抗病基因相应区段的氨基酸序列的同源性为21%-44%,而10个non-TIR亚类RGAS与已克隆的Prf、RPM1、RPS2等抗病基因相应区段的氨基酸序列的同源性为15%-46%。这些抗病基因同源片段(RGA)可做为分子标记筛选甘薯的抗病候选基因。     

甘薯内源激素和化学调控研究进展

本文综述了内源激素在甘薯功能叶片活性差异、同化物运输、尤其是块根的形成和发育中的作用,分析了外源化学调控在促进甘薯增产和抗逆方面的研究进展,并展望了内源激素和化学调控在甘薯上的发展方向。