Granule structure and distribution of allomorphs in C-type high-amylose rice starch granule modified by antisense RNA inhibition of starch branching enzyme

C-type starch, which is a combination of both A-type and B-type crystal starch, is usually found in legumes and rhizomes. We have developed a high-amylose transgenic line of rice (TRS) by antisense RNA inhibition of starch branching enzymes. The starch in the endosperm of this TRS was identified as typical C-type crystalline starch, but its fine granular structure and allomorph distribution remained unclear. In this study, we conducted morphological and spectroscopic studies on this TRS starch during acid hydrolysis to determine the distribution of A- and B-type allomorphs. The morphology of starch granules after various durations of acid hydrolysis was compared by optical microscopy, scanning electron microscopy, and transmission electron microscopy. The results showed that amorphous regions were located at the center part of TRS starch subgranules. During acid hydrolysis, starch was degraded from the interior of the subgranule to the outer surface, while the peripheral part of the subgranules and the surrounding band of the starch granule were highly resistant to acid hydrolysis. The spectroscopic changes detected by X-ray powder diffraction, 13C cross-polarization magic-angle spinning NMR, and attenuated total reflectance Fourier transform infrared showed that the A-type allomorph was hydrolyzed more rapidly than the B-type, and that the X-ray diffraction profile gradually changed from a native C-type to a CB-type with increasing hydrolysis time. Our results showed that, in TRS starch, the A-type allomorph was located around the amorphous region, and was surrounded by the B-type allomorph located in the peripheral region of the subgranules and the surrounding band of the starch granule. Thus, the positions of A- and B-type allomorphs in the TRS C-type starch granule differ markedly from those in C-type legume and rhizome starch.     

一种管道水培叶菜变方位包络定心抓取方式

将不同位姿的水培叶菜包络定心夹持到种植孔中心取出，是实现茎秆精准根切，避免根部残留在管道内的关键。针对定方位抓取方式在一些方位上对叶菜向心包络扶起作用小，抓取成功率低的问题，提出一种在夹持过程中使夹手相对种植孔中心转动的变方位抓取方式。以水培绿宝芥蓝为抓取对象，建立夹手张开伸入、绕种植孔中心转动及闭合夹紧时的尺寸参数关系模型；构建包络定心夹持多刚体动力学仿真模型，对初始倾角为50°、65°和80°，相对种植孔边缘均布的8个方位P₁～P₈上的芥蓝进行包络夹持过程仿真分析；搭建抓取试验平台，对初始倾角为45°～60°、>60°～75°和 >75°～90°，方位为P₁～P₈的芥蓝进行抓取试验。分析确定两手指初始张开角为15°，闭合夹角为30°，夹手变方位转动角为45°，夹手转动速度为两手指转动速度的2倍。仿真获得的变方位夹持倾角为82.18°～88.96°，优于定方位夹持倾角80.32°～88.57°；抓取试验获得的变方位抓持倾角为82.83°～89.65°，优于定方位抓持倾角70.70°～89.27°，仿真与试验结果具有较好一致性，表明变方位夹持不同位姿芥蓝的向心包络扶起作用效果更好。3种初始倾角的变方位抓取试验获得的成功率均值分别为91.67%、95.83%和100.00%，定方位抓取成功率均值分别为87.50%、91.67%和100.00%，表明初始倾角越大抓取机构可获得的抓取成功率越高，变方位抓取初始倾角小的芥蓝可获得更高的成功率；不计P₂方位双层手指伸入碰倒芥蓝样本，变方位抓取获得的最小抓取成功率均值为91.70%，相比定方位在P₁～P₈方位上均具有更好的包络定心抓取效果。研究可为管道水培叶菜采收装备的研制提供依据。     

亚热带禾本科牧草闽牧42的植物学特征和利用价值

主要介绍了闽牧42的植物学特征和利用价值。闽牧42是福建省农业科学院甘蔗研究所以丰产、适应性广的甘蔗栽培品种Co419为母本，以大茎野生蔗的杂种后代PT43-52为父本，经有性杂交选育出用作饲草的新型的C     

安定在碳糊电极上的电化学特性

在０．０５０ｍｏｌ／Ｌ ＨＣｌ和０．０１５ｍｏｌ／Ｌ ＫＮＯ３溶液中，安定在碳糊是极上于－０．７７Ｖ左右产生一灵敏的吸附阴极溶出伏安峰。线性范畴为１．０×１０＾－７￣４．０×１０＾－５ｍｏｌ／Ｌ，检测下限为５．０×１０＾－８ｍｏｌ／Ｌ，测定了血清中的安定含量，结果满意，循环伏安实验结果证实安定在碳糊电极上的吸附为反应物吸附。     

14C-水杨酸在葡萄植株中的运输和分配

将14C标记的水杨酸(salicylic acid,SA)通过涂抹叶片背面引入葡萄幼苗.试验结果表明,水杨酸不易向外运输,具有以韧皮部运输为主、向下运输为主的特点.     

NaCl对转P5 CS基因水稻种子萌发的影响

脯氨酸是植物体内非常重要的渗透调节化合物,它的积累可增加植物对干旱、盐碱的耐受能力。P5CS(Δ1-吡咯啉-5-羧基合成酶基因)在植物中催化脯氨酸生物合成的前两部反应,其活性受到脯氨酸含量的反馈抑制。本研究对转P5CS基因的水稻T4代种子与对照在不同浓度的NaCl胁迫下的萌发进行试验。结果表明,随着NaCl浓度的增高,种子萌发受到的抑制越大,但在100 mmol/L时转P5CS的种子萌发率、生理指标、ABA、脯氨酸和可溶性糖的含量显著高于对照,但可溶性蛋白低于对照。说明转P5CS基因的水稻有显著的耐NaCl胁迫作用。     

日光温室冬春茬番茄套种生菜—夏秋茬黄瓜高效栽培模式

日光温室冬春茬番茄套种生菜，紧接夏秋茬黄瓜，采用“倒栽移苗”等新技术，每667 m² 年产值3.8 万元，纯效益3.2 万元，经济效益显著。     

寒地李和杏遗传多样性SSR分析

以27份适宜北方生长的李、杏品种为试材,采用SSR分子标记技术对其进行遗传多样性分析,并运用UPGMA聚类分析法,分析了27份试材的亲缘关系,为寒地李、杏种质资源保存和品种选育提供分子生物学依据。结果表明:筛选的25对SSR多态性引物共扩增等位位点245个,其中多态性位点240个,多态性比率为97.96%。每对引物的等位基因数量为4~13,平均值为9.8。有效等位基因数平均值为2.740 5,Shannon′s信息指数平均值为1.052 0,多态性信息含量平均值为0.595 5,表明试材具有较高的遗传多样性。聚类分析结果表明,在遗传相似系数0.612处,27份试材可以分为李和杏两大类群。     

BP神经网络结合正交试验法优化Bacillus velezensis Z-27菌株培养基组分

将BP人工神经网络(Artificiai neural network)技术与传统的正交试验方法相结合,提出一种新的试验分析和处理方法,利用神经网络特有的自学能力,对主要影响因素进行仿真优化,获得Bacillus velezensis Z-27菌株培养基组分,即玉米粉2.0％、豆饼粉1.5％、MnSO4· H2O 0.07％,起始pH为7.0、接种量为2.0％,应用优化得到的培养基组分进行验证试验,取得了较好的效果.     

Histopathological observation of cerebral cortex and hippocampus in the mouse with synthetic vascular dementia

AIM:To observe pathomorphological changes in cerebral cortex and hippocampus in the mouse with synthetic vascular dementia.METHODS:The synthetic vascular dementia model was produced in the mouse. Animals were killed 7 d, 15 d, and 30 d after the operation, brain tissues were removed and embedded in paraffin. Section of 8μm thickness were stained with hematoxylin-eosin(HE)and Nissl methods, and observed with light microscope.RESULTS:The cerebral cortex in the mouse became thinner on the seventh day, karyopyknosis in partial nervous cells was formed, the number of local neurons was reduced, sieve structure was observed, and glial cells pro liferated, with the similar results 15 d and 30 d afteroperation.Model mouseπs hippocampal cells in CA₁ area were reduced and almost disappeared 30 d after operation.At the same time, glial cells were abundantly proliferated, tu bercles were formed.Cells in CA₂, CA₃ area were also reduced and hippocampal sclerosis occurred.CONCLUSION:Delayed necrosis of hippocampal pyramidal cells may be the pathological basis of ischemia cerebral vascular dementia.