A biosystematic study of the origin of the cultivated diploid potato,Solanum x Ajanhuiri Juz. et Buk.

Summary The origin and nature of the diploid cultivated potato species S. ajanhuiri Juz. et Buk. was studied. Several lines of evidence indicate that S. ajanhuiri might be derived from natural crosses between primitive cultivars of the diploid species S. stenotomum and the wild species S. megistacrolobum. Morphological comparisons were made between S. stenotomum x S. megistacrolobum F₁ hybrids and naturally occurring S. ajanhuiri to investigate this hypothesis. Comparisons were also made between S. ajanhuiri x S. stenotomum crosses and the F₂ generation of the first-mentioned cross.Crosses between the two major groups of S. ajanhuiri cultivars, Ajawiri and Yari, showed not only genetic breakdown but also a wide range of phenotypic variation similar to those of artificial F₂ families of S. stenotomum x S. megistacrolobum. Furthermore, there was strong evidence showing that the Yari group of S. ajanhuiri could almost certainly be an F₁ S. stenotomum x S. megistacrolobum hybrid, whereas the Ajawiri group could be a backcross of an F₁ hybrid to S. stenotomum. These results added further support to the hypothesis of a hybrid origin of S. ajanhuiri, as well as indicating its putative parents. It is suggested that this hybridogenic taxon be retained at the species level under the name Solanum x ajanhuiri.     

甘薯淀粉白度的研究

用石灰水调整磨浆液ｐＨ值至７．５～８．５，（３０００－４０００ｒ／ｍｉｎ）离心分离和沉淀，能有效改善甘薯淀粉白度。     

紫甘薯初加工产品糊化过程中花青素的浸出特性

[目的]探索紫甘薯高效开发利用的方法。[方法]对2种特定温度下烘干的紫甘薯初加工试样进行模拟糊化,测定糊化不同阶段糊化醪中花青素的浸出量。[结果]紫甘薯粉在糊化时,90℃程序升温至95℃过程,花青素的浸出速率最大。95℃保温结束时,达到最大浸出量。相比110℃烘干,紫甘薯60℃烘干试样花青素保留量大,最大浸出量大,最大浸出率高。[结论]紫甘薯通过较低温度烘干加工,同时适当缩短90℃程序升温前的糊化程序有利于花青素的保留与浸出。     

不同采摘期甘薯茎尖中的硝酸盐 亚硝酸盐和VC含量分析

测定了鲜甘薯茎尖4个品种(胜利100号,卢选1号,一窝红,红腿)不同采摘期的硝酸盐、亚硝酸盐及VC含量。结果表明,4种甘薯茎尖不同采摘期的硝酸盐和亚硝酸盐含量均较低。其中亚硝酸盐含量低于4.0mg/kg,符合我国无公害蔬菜亚硝酸盐的限量标准,硝酸盐含量符合一级蔬菜限量标准,VC含量丰富,均为品质上乘的蔬菜。     

淀粉型甘薯施用烟茎生物有机肥部分替代化肥试验

以渝薯27为材料,采用田间试验方法,研究烟茎生物有机肥部分替代化肥对甘薯的生长和鲜薯产量的影响。以不施肥F1和常规施肥F2作对照,生物有机肥设置8个梯度,生物有机肥从2400 kg·hm-2-1000 kg·hm-2每一梯度递减200kg·hm-2,对应8个梯度的复合肥0-1067 kg·hm-2,复合肥从F4开始每一梯度增加133·hm-2。结果表明：施用烟茎生物有机肥替代22.3%的复合肥,即F9施复合肥933kg·hm-2+生物有机肥1200 kg·hm-2的鲜薯产量最高达39759.7kg·hm-2,鲜薯蔓产量最高达31555.kg·hm-2,淀粉产量9464.7kg·hm-2,是最佳的搭配施肥组合。     

Impact of irrigation with treated low quality water on the heavy metal contents of a soil-crop system in Serbia

Water availability for irrigation is a limiting factor for agriculture in Mediterranean countries. An upcoming strategy for increasing water supply is to use treated wastewater for irrigation. A principal drawback of irrigating with wastewater is the potential heavy metal accumulation in soil and foodstuff.Accumulation of heavy metals in soil and potato plants (Solanum tuberosum L.) irrigated with treated low quality surface water was studied in a three years experiment. The low quality surface water used for irrigation experiments contained a significant proportion of urban sewage and was spiked with selected heavy metals (Cd, Cr, Cu, Pb) and arsenic before treatment for years 2 and 3.The experiments were carried out during the growing seasons of 2006, 2007 and 2008 on a humogley soil of a commercial vegetable farm, 10 km north of Belgrade, Serbia. The growing seasons started in April/May and finished in August. Irrigation water was treated using (1) a conventional sand filter treatment, and (2) a sand filter combined with a specific filter for heavy metal removal treatment.Irrigation water composition was highly variable and cases both of enrichment and depletion of the measured inorganic trace elements were observed in the treated water, compared to the low quality feed water.In spite of this variability of the irrigation water composition, the soil contents in inorganic elements at the end of the three irrigation years are similar to the initial state. After the third harvest, no impact of the irrigation water on potato quality could be detected except for total sugar and sugar in total solids. Statistical tests (ANOVA) were performed to assess similarities between the different set of samples.The principal conclusion of this investigation is that, when appropriately treated, low quality feed waters with high heavy metal contents can be used for irrigation over several years without significant degradation of soil and produces. Even though, long-term cumulative effects in other pedologic and hydroclimatic settings, irrigation and cropping conditions cannot be excluded.     

马铃薯泥鼓风冷冻数值模拟与实验

为掌握马铃薯泥在鼓风冷冻过程中的温度变化规律,建立了短圆柱状马铃薯泥鼓风冷冻的三维数值模型,进行了三维非稳态数值模拟,并结合流场及不同时刻的温度场对马铃薯泥的冷冻过程进行了分析。实验验证表明该模型与实际情况吻合较好,冷冻时间相对误差为3.9%。以此为基础,研究了送风速度和温度对马铃薯泥冷冻过程的影响。结果表明,随着风速的提高,冷冻时间缩短,马铃薯泥内外温差增大,冷冻结束时马铃薯泥中心温度之间的差异先减小后增大。降低送风温度可以缩短冷冻时间,增大马铃薯泥中心温度之间的差异性和马铃薯泥内外温差。送风速度和温度对相变阶段的影响大于预冷段和深冷段。     

温度、pH对马铃薯多酚氧化酶活性的影响

对加工型马铃薯试管苗、茎段愈伤组织、块茎及块茎芽在不同温度、不同 pH条件下PPO活性的检测结果表明 :pH对马铃薯PPO活性具有明显的影响 ,块茎芽以及愈伤组织PPO活性均在 pH 5～ 5 5之间最高 ,分别为 94 2 0及 2 0 4 0 (0 0 1ΔOD/min) ,而试管苗在培养基 pH为 8时PPO活性最高 (19 80 (0 0 1ΔOD/min) )。不同温度下不同品种PPO活性表现不同 ,甘农薯 1号、Atlantic试管苗PPO活性在 18～ 2 5℃之间达到高峰 ,分别为 16 80和 37 2 0 (0 0 1ΔOD/min) ;Shep ody、Snowden试管苗在 5℃下PPO活性较高 ;除此之外 ,不同品种贮藏块茎PPO活性均在 2 5℃表现最高。     

PGPR菌肥对马铃薯产量与肥料利用率影响的初步研究

采用单因素随机区组设计,在辽宁省葫芦岛市绥中县通过大田试验研究了PGPR菌肥对马铃薯产量和土壤氮磷钾养分的影响。结果表明,增施促生菌肥比常规施肥,地下块茎部分钾素吸收率高出9.98%,氮素吸收率高出19.61%,磷素吸收率高出20.1%。马铃薯产量比常规施肥提高12.4%,明显提高肥料利用率,证明在配施生物菌肥的条件下提高马铃薯产量是可行的。     

干旱区脱毒马铃薯高产栽培关键技术

干旱区脱毒马铃薯栽培关键技术是：优化选地整地、优化选种、优化种薯处理、优化播种、优化施肥、优化病虫害防治、优化收获贮藏,重点介绍了垄作覆膜栽培技术、膜侧沟播栽培技术、全膜双垄沟播栽培技术,同类地区有参考价值。