沼渣与化肥配施对马铃薯产量与品质的影响

为探究黑龙江省马铃薯合理施肥水平,提高其产量,以马铃薯品种克新18为材料,采用田间试验方法,研究沼渣与化肥不同比例配合施用对马铃薯产量和品质的影响。结果表明:沼渣和化肥配合使用可以促进马铃薯的生长发育,使马铃薯的现蕾期提前4~5d,块茎膨大期提前3~4d;马铃薯的生理指标在沼渣施用量15~30t时,随着沼渣施用量的增加呈现明显的正相关。沼渣可以提高马铃薯产量2.3%~11.8%;配合施肥能够提高马铃薯的品质,使其淀粉提高了0.05%~0.04%,还原糖增加了0.02%~0.03%。     

我国马铃薯比较优势和出口竞争力分析

以世界马铃薯生产、贸易的历史及现状为背景,论述了我国马铃薯生产和国际贸易的现状,着重分析了我国马铃薯生产的比较优势,比较了世界各国和我国马铃薯的出口竞争力,得出了自己的结论并在此基础上提出了对策建议。     

番薯农谚浅析

番薯自明万历年间传入我国以来,距今已有四百多年的历史,其救灾备荒的属性广为人知。明至民国时期,天灾人祸频发,劳动人民食不果腹,番薯凭借产量大,对种植条件要求低等特点,迅速成为时代的“网红农作物”。新中国成立以来,番薯的产量占农作物的比重也越来越高,番薯的种植面积和产量均居世界第一位。在长期的培育番薯的过程中,劳动人民总结了许多技巧和经验,各地都产生了关于番薯的诸多谚语,涉及育种、藏种、田间管理、插秧技巧和储藏等多个方面。这些农谚不仅对当时的农业生产有指导意义,而且对现在番薯的培育仍有借鉴意义。     

Studies of the evaluation of different genotypes of potato (Solanum tuberosum L.) for yield and mineral contents

Six genotypes of potato were compared with two commercial cultivars, Kufri Chandramukhi and Kufri, Chamatkar for their yield and mineral contents (i.e., iron, copper, zinc, sodium, calcium, magnesium and phosphorus). There were significant differences amongst different genotypes with respect to yield and mineral contents. The cultivar Kufri Chandramukhi, which gave also significantly highest tuber yield during both years, was found to be richest in copper, zinc and potassium. The genotypes EM/B-1601 and JF-4835 were found to be highest in iron content. The highest quantities of sodium, potassium, and magnesium were detected in the cultivar Kufri Chamatkar. The genotype J.F. 5106 was also found to be rich in magnesium content which was comparable to Kufri Chamatkar. The highest quantities of phosphorus and calcium were found in genotypes J.F. 4835 and EM/B-859 respectively. The genotype J.F. 547 was found to be poorest in iron, copper, zinc, sodium and potassium.     

基于流形学习算法的马铃薯机械损伤机器视觉检测方法

针对马铃薯表面芽眼和凹凸不平的影响,使之马铃薯机械损伤难以检测的问题,该文提出了一种基于流形学习算法的马铃薯机械损伤检测方法。首先利用马铃薯图像的显著图分割出马铃薯区域,然后利用主成分分析(principal component analysis,PCA)、等距映射(isometric mapping,Isomap)和局部线性嵌入(locally-linear embedding,LLE)3种流形学习方法提取马铃薯区域图像特征参数,然后分别建立基于3种流形特征的支持向量机(support vector machine,SVM)分类模型PCA-SVM、Isomap-SVM和LLE-SVM,利用网格搜索法(grid search)、遗传算法(genetic algorithm,GA)以及粒子群算法(particle swarm optimization,PSO)3种模型参数优化方法,优化支持向量机模型的惩罚参数c和RBF核参数g,以建立最优分类模型,最后比较3种分类模型的识别效果,确定最优分类模型。研究结果表明,PCA-SVM分类模型对训练集识别率为100%,测试集识别率为100%;Isomap-SVM分类模型对训练集识别率为100%,测试集识别率为91.7%;LLE-SVM分类模型对训练集识别率为100%,测试集识别率为91.7%,表明PCA、Isomap和LLE 3种流形学习方法用于马铃薯机械损伤检测是可行的,其中PCA-SVM分类模型检测效果最优。     

Changes in seed tubers after planting

Summary The changes after planting in weight and dry matter content of seed tubers were studied. The weight was found to increase after planting owing to uptake of water from the soil. The dry matter content decreased rather rapidly. The changes in weight varied within wide limits for individual tubers, showing great differences in water uptake between the tubers. These differences were also demonstrated in a soaking experiment. The variation in water uptake between tubers could partly be explained by variations in the soil but the variation between the seed tubers seemed to be more important.     

Inhibition of aflatoxin-producing fungi by ethyl acetate extracts from gamma-irradiated potatoes

Summary Ethyl acetate extracts prepared from potatoes exposed to a sprout-inhibiting dose (10 krad) of gamma-irradiation were tested for inhibitory activity towardsAspergillus flavus andA. parasiticus. The treatment did not adversely affect the naturally occurring compounds which inhibit growth of these aflatoxin-producing fungi and which were still evident 4 weeks after irradiation following storage at 15°C.     

电流体动力学作用下马铃薯切片的干燥特性变化

电流体动力学干燥作为一种新型干燥技术,以成本低、干燥均匀、高效节能等优势,为热敏性物料的干燥提供了新的方法。为探究电流体动力学作用下马铃薯切片的干燥特性和理化特征,该研究将马铃薯切片在0、14、18、22、26 、30 kV的交流电压下进行干燥,利用红外光谱和低场核磁共振技术分析电流体动力学干燥对马铃薯切片中分子结构、水分迁移的影响。结果表明,马铃薯切片在30 kV电压下的平均干燥速率、有效水分扩散系数、复水比分别为0.9227 g/g·h、2.2653×10^?10 m²/s、4.78,明显优于其他电压下的试验数据。电流体动力学干燥后,马铃薯切片中的官能团没有发生明显变化,蛋白质以β-折叠结构为主。干燥可提高马铃薯切片内部自由水的流动性和降低组织对不易流动水的束缚力,从而促进水分的去除和迁移。电流体动力学干燥技术较好地保留了马铃薯的营养成分,该研究结果为马铃薯切片的干燥提供了理论依据。     

中国马铃薯贸易与营销策略分析

马铃薯贸易和营销对促进马铃薯消费、发展马铃薯产业具有重要的作用。从贸易和销售的角度出发,分析了在新常态和新形势下中国马铃薯产业发展的特点,提出了促进马铃薯产业健康发展的贸易策略和营销策略。研究结论表明：（1）中国是马铃薯生产和消费大国,贸易小国,出口以鲜薯为主。（2）中国马铃薯生产价格底线约为0.82元/kg。（3）马铃薯市场价格波动频繁,价格季节波动明显。（4）马铃薯营销方式传统,营养价值认识不足,消费形式单一,制约国内马铃薯消费。（5）营造良好的贸易发展环境,积极开拓国际市场,推动马铃薯主食化和综合利用产品的消费,促进马铃薯贸易和消费。     

Breeding for apomixis in potato: Pursuing a utopian scheme

Summary Apomictic propagation in potato holds a great promise for the new technology of growing potatoes from botanical seeds in stead of tubers. It is explained that apomixis results from the combination of abnormal meiosis, abnormal fertilization and parthenogenesis.An ideal scheme is given for growing potatoes from true seeds. This scheme remains utopian when autonomous apomixis is not available. Autonomous apomixis occurs when the reduction division is lacking (no gene recombination, no reduction of chromosome number) and the resulting 2n egg cell develops parthenogenetically without fertilization of the central nucleus. The first best approach is pseudogamous apomixis, which differs from autonomous apomixis in the necessity of fertilization of the central nucleus. Second best is the parthenogenetic development of 2n eggs, since these have originated through an abnormal type of reduction division. This type is characterized by the lack of formation of a reduction cell wall and fusion of the two spindles at metaphase II of meiosis (first division restitution).Apomixis in the narrow sense, either pseudogamous or autonomous, is defined. It has not been found in potato species or species hybrids. On the basis of our knowledge about characteristic features of existing apomictic species, about genetics and evolution of apomixis and about the occurrence of particular elements of apomixis in potato the possibility of introducing apomixis into potato from existing elements is discussed along with methods to induce missing elements. Some tentative approaches are suggested which in the long run may lead to the detection of potato genotypes with apomictic propagation.Edited version of a paper presented at the 19th Planning Conference of the International Potato Center (CIP) in Manila, Philippines in September 1979 on production of potatoes from true seed. Published with the consent of CIP.