Effect of Butternut Squash (Cucurbita moschata) Seed Powder on the Chemical and Rheological Properties of Stirred Cultured Camel Milk and Yoghurt

Research shows that producing fermented camel milk is hard because of the milk’s inability to form a firm coagulum, attributed to low levels of κ-casein and ꞵ-lactoglobulin and the large casein micelle size, leading to a weak network of casein formation. In an effort to address this issue, researchers turned to corn starch as a thickening agent, discovering that a concentration of 2.0% effectively improved the viscosity and significantly reduced syneresis in stirred camel milk yoghurt and cultured camel milk. This study explores alternatives to corn starch, focusing on butternut squash seeds as a promising substitute due to their hydrocolloid composition. By incorporating butternut squash (Cucurbita moschata) seed powder (BSSP) as a thickening agent, this study aimed at enhancing the chemical and rheological properties of stirred camel milk yoghurt and cultured camel milk. Fermented camel milk was prepared using 4 litres of camel milk, 2% starter cultures (thermophilic culture for yoghurt and mesophilic aromatic culture for stirred cultured camel milk) and BSSP 0.0% (negative control), 0.4%, 0.8%, 1.2%, 1.6%, 2.0% mixed with 0.4% gelatin. 2.0% corn starch mixed with 0.4% gelatin was used as a standard for comparison. Results showed that increasing the BSSP level significantly (p < 0.05) decreased the moisture content while increasing the total solid content of stirred fermented camel milk products. There was an increase in ash content with an increase in BSSP levels. There was a significant (p < 0.05) reduction in the pH, with an increase in BSSP levels in stirred fermented camel milk samples. Increasing the concentration of BSSP from 0.4% to 2.0% resulted in a significant (p < 0.05) increase in viscosity and a reduction in syneresis of stirred camel milk yoghurt and stirred cultured camel milk samples. This study demonstrated that BSSP effectively enhances the viscosity, reduces syneresis and increases acidity in stirred fermented camel milk products during storage.

Effect of travel speed on seed spacing uniformity of corn seed meter

Both seeding performance of seed metering unit and travel speed of seed planter have significant effects on seeding quality,thereby affecting crop growth and yields.In order to determine the effects of different travel speeds on seed spacing uniformity,four different types of seed meters were evaluated at five different travel speeds on seed meter test bench and in field.The tested seed meters included a finger pickup seed meter,a scoop-wheel seed meter,an air-pressure type seed meter and an air-blowing type seed meter.The seeding performance of the horizontal distribution of seeds within a row was described by using the coefficient of variation,the quality of feed index,the multiple index and the miss-seeding index.Experiments were performed in laboratory and field,respectively.Results indicated that different travel speeds have statistically significant effects on seed spacing uniformity.The four types of seed meters performed better on the seed meter test bench than in the field.Coefficient of variation increases and quality of feed index decreases as the travel speed of seed planter increases.The best seed spacing uniformity was obtained with the air-pressure type seed meter,followed with the air-blowing type seed meter,the finger pickup seed meter and the scoop-wheel seed meter.There were considerable differences between the performances of the scoop-wheel seed meter in the bench test and field test;the seeding qualities were much better in the bench test than in the field test.The scoop-wheel seed meter is more sensitive to vibration than the other types of seed meters.

Identification of damaged corn seeds using air-coupled ultrasound

Corn,an important staple in many countries around the world,is subject to a very inefficient germination rate due to worm-damaged seeds.However,air-coupled ultrasound is a rapid,safe and widely accepted method for the early detection of such damage.In this study,the current effectiveness and future prospects of this technique for identifying damaged seeds were explored.The presented procedure started with drawing a sample of 810 seed particles,consisting of 400 that were intact,400 manually damaged and 10 damaged by worms.Then the principal component analysis(PCA)method was used to reduce the dimensions of air-coupling ultrasonic information and extract the top ten principal components.Finally,a KNN decision tree by using SIMCA software and a Fisher recognition model by using MATLAB software were constructed.The pattern recognition was established by using KNN,which has the most accurate recognition rate.The correct recognition rate of modeling for the front and back data of the intact particles was 98%and 100%,respectively;and for the manually damaged particles,99%and 97%,respectively.The results show that the model developed by using air-coupled ultrasonic data can classify corn seed particles both with and without holes to provide a basis for the development of a seed selection system,which has a significant role in improving the clarity and the germination rate.

Effect of Wood Vinegar on Seed Germination and Water Implantation of Corn

To analyze the effect of wood vinegar on seed germination and seedling growth, the seeds of corn are dipped in wood vinegar of different densities. The results showed that significant effects were found through all the treatments on the seed germination rate, the seed germinating energy and the germinating index. The regress CUBICS curves were developed to describe the relation. The reasonable parameters range was obtained. At the same time, the corn was cultivated by wood vinegar of different densities, aiming to study the effect of wood vinegar on biomass. It showed that all treatments had obvious effects on the seedling length and dry weight aboveground, the chlorophyll and dry weight underground were not included. The research results could be used to direct the wood vinegar deeply refining process and product development.

Seed Health Status of Sweet Corn (Zea mays L. saccharata Sturt) from Five Areas in China and Effect on Field Seedling Emergence

The health status of 18 sweet corn (Zea mays L. saccharata Sturt) hybrids classified to two types, collected from five areas in China, was examined by PDA method, and factors influencing seed health and relationships between seed health and field seedling emergence were studied. Seventeen fungal genera were isolated and Fusarium was the most frequently isolated. There were significant differences both in incidence of Fusarium and in percentage of infected seeds among 18 hybrids. Research also showed that significant and consistent differences both in seed-borne fungal taxa and in percentage of infected seeds existed between two types of sweet corn. Sugar enhanced corn is more slightly infected than super sweet corn both in fungal taxa (13 and 16, respectively) and in percentage of infected seeds (62.0 and 79.2%, respectively). There were also significant differences both in seed-borne fungal taxa and in percentage of infected seeds among five areas. Seeds from South China were most severely infected, for there were 14 fungal genera detected and the percentage of infected seeds was highly 99.1% while those from Northwest China were slightly infected, for there were 10 fungal genera detected and the percentage of infected seeds was only 14.3%. Further research showed that there were significant negative correlations both between incidence of Fusarium and percentage of field seedling emergence and between percentage of infected seeds and percentage of field seedling emergence. Percentage of field seedling emergence could be estimated by regression equations built by regression analysis.

Soybean seed protein, oil, fatty acids, and mineral composition as influenced by soybean-corn rotation

Effects of crop rotation on soybean (Glycine max (L) Merr.) seed composition have not been well investigated. Therefore, the objective of this study was to investigate the effects of soybean-corn (Zea mays L.) rotations on seed protein, oil, and fatty acids composition on soybean. Soybeans were grown at Stoneville, MS, from 2005 to 2008 in five different scheduled cropping sequences. In 2007, following three years of rotation with corn, seed oleic acid percentage was significantly higher in any crop rotation than continuous soybean. The increase of oleic fatty acid ranged from 61 to 68% in 2007, and from 27 to 51% in 2008, depending on the rotation. The increase of oleic acid was accompanied by significant increases in seed concentrations of phosphorus (P), iron (Fe), and boron (B). In 2007, the increase of P ranged from 60 to 75%, Fe from 70 to 72%, and B from 34 to 69%. In 2008, the increase of P ranged from 82 to 106%, Fe from 32 to 84%, and B from 62 to 77%. Continuous soybean had higher linoleic:oleic ratio and linoleic: palmitic + stearic + oleic ratio, indicating that relative quantity of linoleic acid decreased in rotated crops. The total production of protein, oil, stearic and oleic fatty acids was the lowest in continuous soybean. The total production of palmitic acid was inconsistent across years. The results show that soybean- corn rotation affects seed composition by consistently increasing seed oleic fatty acid, P, Fe, and B concentrations. Higher oleic acid, unsaturated fatty acid, is desirable for oil stability and long-shelf storage. The mechanisms of how these nutrients are involved are not yet understood.

玉米种子真空冷冻干燥微观实验研究及模型分析

目的 探究真空冷冻干燥技术对玉米种子的影响。方法 基于光学显微镜成像及真空冷冻干燥技术探究各冻干条件(冻结终温、升华干燥温度、解析干燥温度)对玉米种子细胞微观结构的影响。对比分析细胞形态学参数(当量直径、周长、面积、圆度)和含水率的变化规律,建立真空冷冻干燥条件与细胞形态学参数变化率之间关联的数学拟合模型。结果 细胞形态学参数变化率和含水率与冻结终温呈负相关趋势,随升华干燥和解析干燥温度的升高呈现先减少后增大的趋势,且升华干燥温度对玉米种子形态学参数变化率影响最大。在冻结终温为-25℃、升华干燥温度为5℃、解析干燥温度为40℃下,含水率(12.81%)最低。在细胞的当量直径(9.2%)、周长(8.4%)、面积(17.68%)的变化率最小且圆度(1.78%)小于4%时,干燥效果最好。采用二次多项式模型,决定系数R2均接近于1,FSSE和FRMSE均接近0。结论 该数学模型能较好地描述各真空冷冻干燥条件对玉米种子细胞形态学参数的影响,可在一定范围内对玉米米种子真空冷冻干燥后的品质进行控制。

夹持式玉米膜上精密穴播轮的参数优化及试验

为优化提高玉米膜上穴播轮的播种精度,针对目前玉米膜上精密穴播轮装置单粒率低、空穴率较高等问题,根据玉米播种时的特殊要求,优化设计了一种农机与农艺深度结合的玉米膜上精密穴播轮。系统介绍了所设计装置的机械结构及工作原理,并通过对穴播轮的结构和工作原理分析,确定将取种器中夹种板板长、夹种板偏角及夹种板与接种杯间距为作为影响试验结果的关键试验因素,将单粒率和空穴率作为目标值,通过数学软件对影响单粒率Y1和空穴率Y2的因素进行数据处理并全面优化,得到影响单粒率Y1的显著因素顺序为夹种板与接种杯间距X_(3)>夹种板板长X_(1)>夹种板偏角X_(2),影响空穴率Y2的显著因素顺序为夹种板与接种杯间距X_(3)>夹种板偏角X_(2)>夹种板板长X_(1)。优化分析与试验验证结果表明:当取种器中夹种板板长X_(1)为17mm、夹种板偏角X_(2)为40°、夹种板与接种杯间距X_(3)为32mm时,单粒率Y1为92.09%,空穴率Y2为3.35%,与优化结果的相对误差分别为1.57%、3.74%,数值上均小于5%,满足玉米精密排种的作业要求。

新疆制种玉米生产机械化技术——种植与田间管理

新疆制种玉米在种植过程中,玉米父本和母本播种时间不同,通常情况下,制种玉米父本需要播种2次。制种玉米田间管理需要放苗、除草、中耕、间苗、去除杂株、去除玉米母本雄穗和去除玉米父本。在去除杂株、去除玉米母本雄穗和去除玉米父本环节,需要专用的农业机械,但是针对上述环节的专用农机具尚不成熟或没有相应的农机具,制约了新疆制种玉米种植技术水平的发展,影响了制种玉米种植收益。为此,应制定制种玉米种植技术规范对广大种植户进行技术培训,加快研制制种玉米种植专用农机具,政策引导制种玉米有序规范种植。

真空冷冻干燥升华温度对玉米种子品质的影响

本文采用真空冷冻干燥机对玉米种子进行冷冻干燥处理,研究不同升华温度(3℃、5℃、7℃、9℃)条件下其物性指标(含水率、容重、出碴率、颗粒度指数、裂纹率、最大力、最大力点变形)和活性指标(发芽率、呼吸强度、相对导电率)的变化规律。研究结果表明:玉米种子的含水率、容重、出碴率、最大力、最大力点变形随升华温度升高先降低后升高,颗粒度指数随升华温度升高先增大后减小,裂纹率、相对电导率随升华温度升高先升高后降低。不同升华温度的玉米种子活性都有所下降,发芽率也都有所下降。在升华温度5℃下玉米种子呼吸强度最小,最适宜储存。

基于四行精密播种的玉米直播机设计与试验

为了解决播种玉米种子精度低的问题,设计了一款基于四行精密播种的玉米直播机,可实现玉米种子快速、精准播种。试验表明:该玉米直播机移动性能好、播种速度快、种植深度和每穴种子数量更加准确,封土情况也大幅改善,符合设计需求,具有较高的可靠性和可行性。

玉米免耕播种机振动特性及对排种器排种性能的影响

为研究玉米免耕播种机振动特性以及振动对排种器漏播指数和重播指数的影响,搭建一套由振动加速度传感器、电荷放大器、USB采集卡组成的播种作业振动测试系统,在玉米免耕播种机免耕地表作业时进行振动测试采集播种作业的振动信号。因田间工作环境复杂,使用经典滤波法中的IIR滤波器滤除所采集振动信号中其他高频干扰信号,对田间采集振动信号进行时域分析,均方值作为时域分析指标值。结果表明:振动加速度均方根随着作业速度和旋耕机转速的增加呈线性增加,旋耕机转速和作业速度是引起玉米免耕播种机振动的主要因素,影响顺序为:旋耕机转速>作业速度。使用二次积分法对田间采集信号进行分析,得出播种机作业时最大振动位移为16.004mm,对振动信号进行频域分析,使用直接法求出功率谱密度。结果表明:玉米免耕播种机振动频率主要在0~100Hz之间,频率分布与旋耕机转速影响较大。根据田间振动信号所得工作参数搭建振动试验台,以播种机振动频率、振动幅值、作业速度为试验因素,合格指数、漏播指数为评价指标进行3因素3水平响应面试验。结果表明:作业速度、振动幅值和振动频率对合格指数和漏播指数影响较为显著。各因素对合格指数影响顺序为:振动幅值、作业速度、振动频率;各因素对漏播指数影响顺序为:振动幅值、振动频率、作业速度。研究结果可为降低玉米免耕播种机振动和优化指夹式排种器提供理论参考。

微生物种衣剂的研制及其对玉米茎腐病的防效评价

本研究通过平板对峙、种子发芽性状和室内盆栽试验,筛选对玉米茎腐病防效优良的木霉菌株,通过助剂理化性质测定、生物相容性分析及正交试验,明确助剂种类、用量和最佳组合,研制生物种衣剂,并进行玉米茎腐病防效验证。结果表明:从实验室保存的109株木霉中,筛选到17株木霉对禾谷镰孢具有较好拮抗活性,抑制率均>70%,6株木霉菌株对苗期茎腐病的防治效果最佳,防效80.33%~85.64%。分别以筛选的棘孢木霉Tr34和非洲哈茨木霉Tr35为活性成分,10^(6)厚垣孢子数/mL,辅以黄原胶0.2%,木质素磺酸钠2%,北农成膜剂1,5%,100 mg/mL链霉素1%,制备100万孢子/mL棘孢木霉生物种衣剂(简称Tr34生物种衣剂)和100万孢子/mL非洲哈茨木霉生物种衣剂(简称Tr35生物种衣剂)。两种生物种衣剂药种质量比例分别为1:200和1:100时,对苗期茎腐病的防效最好,分别为81.14%和83.18%。本研究研制的Tr34生物种衣剂和Tr35生物种衣剂可以有效降低玉米茎腐病的发生,为进一步田间应用奠定基础。

新疆制种玉米生产机械化技术——去雄

新疆是我国重要的制种玉米种植区,玉米母本的雄穗去除是制种玉米种植的关键环节之一。受种植模式和去雄技术要求的影响,不同地区在去雄方法、机械去雄使用情况上存在不同。人工去雄可以根据雄穗的生长情况,选择性的去除,整个去雄期需要进行5~6次抽雄。机械去雄采用直接抽雄或者先切顶然后抽雄两种方法,抽净率为80%~95%,机械去雄对叶片的损伤较大,机械去雄后需要人工检查并对未去雄玉米母本再次抽雄。为了全面推广应用机械去雄技术,应进一步规范和提高适于机械化作业的种植模式、机械抽雄技术以及去雄机的整机性能。

中波紫外线辐照对甜玉米种子萌发的影响及转录组分析

【目的】研究中波紫外线(UV-B)辐照处理对甜玉米种子萌发及相关基因表达的影响,为解析UV-B辐照促进种子活力的分子机理奠定基础。【方法】以甜玉米自交系T28种子为材料,设置0(CK),0.5,1,2,4和8 h共6个不同时长的UV-B辐照处理,对处理和对照(CK)种子萌发相关的表型指标、生理指标进行分析,同时借助转录组测序技术筛选促进玉米种子萌发的差异表达基因。【结果】UV-B辐照处理1 h时甜玉米自交系T28种子的发芽率最高,发芽势、发芽指数和活力指数随着UV-B处理时间的延长均呈先上升后下降的趋势,且在UV-B辐照处理1 h时达到最高。UV-B辐照处理1和2 h的甜玉米种子萌发72 h后,萌发种子的CAT、POD活性和游离脯氨酸含量均高于CK。对0(CK),1和2 h辐照处理下的差异表达基因进行趋势表达分析,获得8个不同趋势的基因集profile(0-7),其中profile2中1 716个转录本表达量呈先下降后上升趋势,profile5中919个转录本表达量呈先上升后下降趋势。GO富集分析表明,在生物过程、细胞组分、分子功能类别中,profile2基因集中富集最显著的分别为蛋白磷酸化、膜整体组件、转移酶活性和转移己糖基,profile5基因集中富集为翻译、核糖体、核糖体的结构组分。KEGG富集分析发现,profile2基因集中显著富集的通路主要注释在苯丙素类生物合成、次生代谢物的生物合成、代谢途径等;profile5基因集中显著富集的通路为淀粉和蔗糖代谢、氧化磷酸化及蛋白酶体。淀粉和蔗糖代谢通路中13个基因与各样本表达量聚类分析表明,在处理1 h样本中这些基因的表达显著上调。【结论】UV-B处理可以提高甜玉米种子的活力,处理时长1 h的效果最显著,推测不同时长处理下的差异表达基因与种子活力密切相关。

近红外光谱分析技术在玉米品质检测中的应用研究进展

玉米是我国重要的粮食作物和动物饲料来源。为实现精准化营养和自动化加工,在玉米种植、仓储、深加工、饲用等领域,玉米的营养品质、安全指标及种子质量等备受关注。传统的化学检测方法会对样品产生破坏,耗时耗力,并且需要专业的技术人才进行操作,难以满足日益增长的玉米检测需求。近红外光谱分析技术具有检测速度快、操作简单、多组分同时分析等优点。本文主要综述近红外光谱分析技术在检测玉米的化学成分、安全指标、种子质量等方面的研究进展,旨在为近红外光谱分析技术在玉米的品质评价、种质选择等方面的检测应用提供参考。

基于高速摄像的玉米排种器性能测试

随着现代农业对高效、精确播种技术需求的增加,传统的排种器性能测试方法已经难以满足要求。该文基于高分辨率高速摄像机,在不干扰排种器正常工作的情况下实时捕捉和分析排种过程,通过获得排种器在高频率下的连续图像了解种子在被排出瞬间的运动轨迹和分布情况。试验结果表明,该方法可以准确地检测排种器的排种速度、排种均匀性和漏播率,为优化和改进玉米排种器设计提供了可靠的数据支持。通过该技术手段,可以大幅度提升玉米播种器的效率和质量,不仅有助于提高玉米的播种质量和效率,还可以为农业生产提供重要的技术支持和保证。

指夹式亚高速玉米播种不同导种管种子运移轨迹对比

为了解决玉米亚高速播种机作业速度为8~12km/h条件下,指夹排种器导种管选型问题,以14°和16°两种角度的导种管为研究对象,通过自制试验台架并利用高速摄像技术对玉米种子在不同导种管中的运动过程进行追踪拍摄,描述了指夹排种器分别在作业速度8~12km/h、倾斜角度0°~30°、离地高度2~4cm 3种因素下,种子落入不同导种管的位移轨迹,结果表明:种子在16°导种管比在14°导种管中弹跳剧烈。

制种玉米去雄无人机旋切装置设计与试验

针对制种玉米母本植株由地面去雄机械去雄后存在遗漏雄穗及机械化补漏去雄装备缺乏等问题,提出了一种适配四旋翼无人机的旋切装置。基于去雄无人机作业特点与稳定性影响因素,分析了刀具切割雄穗时的受力及其对无人机反扭力矩的影响,并轻量化设计了旋切装置总体结构,确定了旋切装置的旋切范围为44~150 mm,可展范围为541~1318 mm,总质量为4.03 kg。通过旋切部件切割建模与仿真,选取了竖直进给切割的旋切方式,并由台架试验得到了旋切装置切割反扭力矩最小时的最优参数组合。在上述基础上将旋切装置与无人机集成开展田间试验。研究表明,当旋切转速3954 r/min、竖直进给速度5.9 mm/s、刀具刃角32°时,旋切装置单位切割力为10.54 MPa,能完全切除雄穗,去雄无人机田间叶片损伤率为14.58%,高度波动率为1.88%,满足制种玉米去雄要求。

干旱胁迫下两种芽胞杆菌对玉米幼苗促生作用研究

供试玉米品种为‘先玉335’(XY335),供试菌株为NECC11322(Bacillus subtilis)枯草芽胞杆菌、NECC11324(B.megaterium)巨大芽胞杆菌。试验设4组处理:Con(无菌水浸种,干旱胁迫),C1(无菌水浸种,正常供水),C2(NECC11322菌液浸种,干旱胁迫),C3(NECC11324菌液浸种,干旱胁迫),测定了浸种后盆栽玉米幼苗的生长状况、抗性生理指标及植株的N、P、K含量。结果表明:在干旱胁迫下接种NECC11322、NECC11324后,玉米幼苗叶片及根系SOD、POD、CAT、APX活性较Con均不同程度升高,其中接种NECC11322根系POD活性增长最为显著,较Con增长67.78%;植株叶片及根系可溶性蛋白含量、可溶性糖含量较Con均呈上升趋势,其中接种NECC11322叶片可溶性糖含量增长最为显著,较Con增长152.10%;与Con相比,植株叶片及根系全氮、全磷、全钾养分含量均有所提升,接种NECC11322后叶片全氮含量升高最为显著,较Con增长88.47%;干旱胁迫下接种两种芽胞杆菌后,植株叶片及根系丙二醛含量较Con均显著降低,接种NECC11322后根系降幅最为显著,较Con降低51.03%。综上可知,干旱胁迫下接种两种芽胞杆菌均可降低干旱胁迫对玉米幼苗生长的抑制,其中NECC11322菌株更具有抗旱性。通过提高保护酶活性、可溶性蛋白、可溶性糖含量、叶绿素含量以及植株养分含量提高玉米幼苗抗旱性,促进玉米幼苗生长。