Effects of Stable Chlorine Dioxide on Sterilization and Preservation of Fresh-cut Narrow-leaf Cattail

At present, chlorine dioxide has been widely used as a bactericide that may become an alternative to chlorine. In this study, fresh-cut narrow-leaf cattail was soaked with 45, 70 and 95 mg/L chlorine dioxide solution, respectively. Fresh-cut narrow-leaf cattail samples were collected regularly to determine changes in surface microbe amount, cellulose content, Vc content, reduction sugar content and sensory quality of narrow-leaf cattail, thus analyzing the effects of chlorine diox- ide on sterilization and preservation of fresh-cut narrow-leaf cattail. The results showed that all three concentrations of chlorine dioxide solution could significantly reduce the amount of microbes on the surface of fresh-cut narrow-leaf cattail and improve the edible safety of products. The initial sterilization efficiency was im- proved gradually as the concentration of chlorine dioxide increased. In addition, chlorine dioxide treatment postponed the increase of cellulose content of fresh-cut narrow-leaf cattail. However, chlorine dioxide oxidized Vc and reducing sugar, and its bleaching effect also exerted a certain impact on the sensory quality of fresh- cut narrow-leaf cattail. Based on comprehensive comparisons, 45 - 70 mg/L chlorine dioxide solution exerted the best effects on sterilization and preservation of fresh-cut narrow-leaf cattail. This study laid the foundation for the production and application of chlorine dioxide solution and promotion of rapid development of nar- row-leaf cattail industry.

The Biology of <i>Szelenyiopria talitae</i>(Hymenoptera: Diapriidae): Larval Parasitoid of the Leaf-Cutting Ant <i>Acromyrmex subterraneus</i>(Hymenoptera: Formicidae)

The biology of a koinobiont parasitoid of leaf-cutting ant larvae, Szelenyiopria talitae (Hymenoptera: Diapriidae), was studied from naturally infested Acromyrmex subterraneus (Hymenoptera: Formicidae) nests. Nests were collected in the field from the Atlantic rainforest biome in the state of Rio de Janeiro. A total of fifty-three nests were collected from 2015 to 2018. Parasitized nests were only found during the months of September and October. Approximately 22% of the nests collected over a four-year period were found to have been parasitized by S. talitae. The mean within-nest parasitism rate was 66.3%. This diapriid displayed both solitary (14%) and gregarious parasitism (86%), with up to a maximum of 12 parasitoids developing within a single host. Gregarious parasitism with two (29%) or three (21%) S. talitae per host was most frequently observed. There was a positive correlation between the number of parasitoids per host and host size (dry weight), indicating that S. talitae females oviposited a higher number of eggs in larger hosts. There was also a negative correlation between S. talitae pharate adult size and the number of parasitoids per host, which could have been caused by sibling competition for limited host resources. The high levels of parasitism seen here had a debilitating effect on the colonies. Acromyrmex subterraneus is a serious pest in Brazil, and these studies lay the foundation for understanding the impact of S. talitae on ant populations.

Attractivity or Repellence: Relation between the Endophytic Fungi of <i>Acalypha</i>, <i>Colocasia</i>and the Leaf-Cutting Ants—<i>Atta sexdens</i>

Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can be a defense mechanism against the attack by the leaf-cutting ants. Ants of the genus Atta are known as leaf-cutting ants and have an obligatory association with the fungus Leucoagaricus gongylophorus, cutting pieces of leaves and bringing them back to the colony to the fungus. The present study aimed to find out the endophytic fungi community of an attractive plant (Acalypha wilkesiana) and a less attractive plant (Colocasia esculenta) to the ants Atta sexdens. We found out that the communities are different in quantity and in composition and 73% of the isolated fungi were from A. wilkesiana, which has fungi known as attractive to leaf-cutting ants, such as genus Colletotrichum, Pestalotiopsis, Phomopsis and Xylaria. On the other hand, in C. esculenta, there was found the genus Fusarium, known to be reject by the leaf-cutting ants, and less fungal diversity than in the attractive plant A. wilkesiana. Therefore, our data suggest that attractivity or repelence of a plant to the leaf-cutting ants could be related to presence or ausence of determinated fungi more than the quantity of fungi present in a leaf.

Spatial Statistics and Age Structure of Leaf Cutting Ant Nests

In this study, we investigated the spatial aggregation of old and incipient nests of Atta sexdens rubropilosa by fitting Poisson and Negative binomial models to nest abundance data. Our aim is to analyse the distribution of ant nests in eucalypt regrowth, Cerrado and native forest fragment. We also investigated the correlation between nest abundance and climatic factors, as well as different nest ages. When comparing nests of different ages we observed an aggregated pattern for both old and incipient nests. On the other hand, analysing the distribution of nests separately, only taking into account the different areas and respective borders, old nests exhibited an aggregated pattern and incipient nests showed a random pattern, except for native forest with ants exhibiting only an aggregated pattern. The levels of aggregation changed in response to different areas and border gradients, with more external borders showing higher aggregation than more internal borders. Temperature was the variable showing the highest correlation with nest abundance and the correlation between nests of different ages was totally depending on the different areas.

不同剪梢程度对农桑14号春季经济性状及产叶量构成的影响

[目的]分析不同剪梢程度对农桑14号春季经济性状和桑叶产量及其构成的影响,为农桑14号的春季剪梢提供技术参考。[方法]对桑树枝条进行1/4、1/3、1/2剪梢处理,调查不同处理的发育历期、止芯芽性状、生长芽性状、枝条长度及桑叶产量表现。[结果]在发育时间上,剪梢1/4、1/3与剪梢1/2的处理从膨芽期到雀口期,发育历期呈增大趋势;在开叶阶段,发育历期呈缩短趋势;到桑叶成熟期,发育历期呈增大趋势。在桑叶产量及其构成上,剪梢1/4处理平均产量2.413 kg/株,其中生长芽叶重2.068 kg/株,占85.70%,止芯芽叶重0.345 kg/株,占14.30%;剪梢1/3处理平均产量3.042 kg/株,其中生长芽叶重2.612 kg/株,占85.86%,止芯芽叶重0.345 kg/株,占11.34%;剪梢1/2处理平均产量2.172 kg/株,其中生长芽叶重1.875 kg/株,占86.33%,止芯芽叶重0.297 kg/株,占13.67%。[结论]采用1/4或1/3剪梢处理,大蚕用叶可提前到4月28日,且桑叶产量高于1/2剪梢处理,对全年多批次养蚕的时间调控和桑叶保障更加有利。

Effect of Leafy and Leafless Greenwood, Softwood and Hardwood Cuttings Success of <i>Garcinia kola</i>(Heckel)

Garcinia kola Heckel, called “petit cola” in Côte d’Ivoire and “bitter kola” in Nigeria, is a Non-Timber Forest Product of great socioeconomic importance. Unfortunately, this species is threatened due to overexploitation and deforestation. This study tested the effect of leaf area on stem cuttings to regenerate vegetatively in a non-mist poly-propagator without using exogenous hormones. Three stem cuttings types: greenwood, softwood and hardwood (12 - 15 cm in length) were collected from 24-month years old seedlings. The two top leaves of each cutting type were conserved at different leaf area: 0 cm2, 28.25 cm2, 56.5 cm2, 84.75 cm2 and 113 cm2 (entire leaf area). Observations were made on rooting, sprouting and leafing abilities of cuttings depending to treatments applied. Results showed that all cutting types have presented good ability to shooting and rooting. Cuttings with 113 cm2 leaf areas presented the best rooting (94.44% ± 2.42%) and shouting (95.55% ± 2.42%) percentage and longest primary root length (12.03 ± 0.50 cm). Hardwood, softwood and greenwood cuttings with 113 cm2 leaf area had the best rooting percentage (96.66% ± 3.33%, 96.66% ± 5.77% and 90.00% ± 5.77% respectively). The longest primary root length (13.50 ± 0.97 cm) was observed to greenwood cuttings with 113 cm2 leaf area. Regenerated plants in the forest presented well survival percentage (96.66%). This study shows that it is possible to regenerate entire plants by cuttings without using external hormones in non-mist poly-propagator.

黑果腺肋花楸扦插生根特性及不定根发生模式研究

【目的】为了解黑果腺肋花楸扦插不定根起源及发育过程,揭示其扦插生根机理。【方法】以‘福康源1号’当年生半木质化插穗为研究材料,利用水培扦插技术和石蜡切片法对不定根形成过程中插穗内部组织结构及外部形态的变化规律进行观察。【结果】在水培条件下,IBA处理扦插生根期为30~40 d,扦插过程中皮孔处在10~15 d出现不定根,插穗切口处在15~20 d出现不定根,生根速度、不定根数量及根长均优于对照,外源诱导可显著提高生根率和生根质量。扦插前的插穗内无潜伏根原基存在,不定根原基在插后形成;不定根形成为愈伤组织生根型和内部分生组织生根型。皮部产生的不定根起源于维管形成层、韧皮薄壁细胞或皮层;愈伤组织产生的不定根是由愈伤组织内的薄壁细胞团特化而成;叶隙或枝隙是形成不定根原基和产生愈伤组织的主要区域。【结论】扦插生根属于多位点发生模式,属于诱导生根型。

莓叶委陵菜叶插繁殖技术研究

莓叶委陵菜(Potentilla fragarioidis)作为我国北方地区极具开发潜力的乡土地被植物,存在着有性繁殖材料不易获得且繁殖系数较低的问题。而扦插繁殖作为一种无性繁殖手段,能为莓叶委陵菜的快速繁殖提供新的途径。本研究以莓叶委陵菜生长健壮、无病虫害的叶为试验材料,通过正交试验针对不同扦插基质、激素种类及其浓度对莓叶委陵菜叶插生根效果的影响进行探究。结果表明,莓叶委陵菜插穗在扦插45 d后能够形成根系,不同处理水平的扦插基质、激素种类及其浓度间的交互效应对插穗生根效果的影响具有显著差异(P<0.05)。扦插基质是影响莓叶委陵菜叶插生根率的主导因子,而激素种类是影响平均单株生根数、平均单株总根长、最长根长和根系效果指数的主要因素。以草炭+珍珠岩+蛭石(1:1:1)为基质,扦插前使用300 mg·L^(-1)的IBA对插穗进行处理生根效果最佳,该处理方式下扦插生根率达63.33%,平均单株生根数为6.90条,平均单株总根长为27.98 cm,最长根长13.83 cm,根系效果指数达20.50。本研究结果可为莓叶委陵菜无性系繁殖体系的快速建立提供理论依据。

4TQ-2A型甜菜切顶机的设计与试验

针对现有分段式甜菜切顶机切顶效率低、效果差等问题,设计了4TQ-2A型甜菜切顶机,采用两回转轴对向旋转方式清理缨叶,并通过单因素试验确定了橡胶条型号和最佳工作转速。同时,通过对切顶装置结构及其在工作过程中运动特性分析,确定了切顶装置的关键尺寸和最佳切割角度。田间试验表明:4TQ-2A型甜菜切顶机设计合理,当前进速度为1m/s、清缨装置转速为800r/min、切顶装置切割角为30°时,经过5次重复试验得到切顶合格率平均值为95.56%,甜菜损伤率平均值为2.6%,有效解决了甜菜缨叶清理不净、切刀易堵塞等问题,降低了作业过程中甜菜的损伤率,提高了切顶质量及合格率,满足甜菜机械化切顶作业要求。研究可为甜菜机械化收获装备的进一步研究奠定基础。

非遗文化黄梅挑花对地方特产的包装设计研究——以黄梅荷叶茶为例

黄梅挑花作为湖北省黄梅县非物质文化遗产,具有独特的地域特征和艺术价值。黄梅荷叶茶历史悠久,是黄梅县当地的特色产品。本文对黄梅挑花装饰艺术进行分析,将黄梅挑花的艺术形式运用到黄梅荷叶茶的包装设计中,旨在探索出一条将非遗文化与地方特产相结合的包装设计方法,为助力乡村振兴和弘扬非物质文化寻求新的路径。

Effect of Synthetic Hormone Substitutes on Rooting of Vine Cuttings in Water Yam (Dioscorea alata L.)

The use of yam vine cuttings as propagules with appropriate synthetic rooting hormones such as IBA (Indole-Butyric Acid) and NAA (Naphthalene Acetic Acid) has previously been reported as successful but expensive. To source for cheaper alternatives, this study compared the effect of some natural and synthetic hormones on rooting of vine cuttings in two varieties of Dioscorea alata. Vine cuttings from three months old water yam varieties were treated separately with 1%, 3% and 5% concentrations of each of the following: neem leaf ash, coconut water, 2,4-D and IBA with water as control. Treated cuttings were planted in triplicates in polythene bags using the completely randomised design and watered once in two days for 49 days. Data collected on rooting percentage, number of roots per plant, mean root length, number and length of new vines were subjected to analysis of variance tests and the means separated using least significant difference tests. A 100% rooting was observed in vines treated with 1% or 3% coconut water and neem ash. These vines also generated significantly greater number of new vines (P < 0.05) compared to those from synthetic hormones. Vines treated with 5% neem produced the highest number of roots (145.33 ± 9.21;P < 0.001) while those treated with 3% neem produced the longest roots (45.3 ± 9.23 cm) followed by those treated with 3% coconut water (24.3 ± 3.48). The study reveals that neem leaf ash and coconut water are better root promoting agents for water yam vines than 2,4-D and IBA and could be tested further for use as natural hormonal substitutes to the synthetic hormones.

永福报春苣苔叶片扦插过程中内源激素含量的动态变化

【目的】探明永福报春苣苔(Primulina yungfuensis)叶片在扦插过程中内源激素含量的变化,为其扦插繁育技术和外源激素调控研究提供理论依据。【方法】以永福报春苣苔叶片为插穗,采用高效液相色谱串联质谱法(HPLC-MS/MS),测定其扦插过程中内源激素吲哚乙酸(IAA)、吲哚丁酸(IBA)、异戊烯基腺苷(IPA)、脱落酸(ABA)、玉米素(ZT)、反式玉米素核苷(TZR)及赤霉素(GA1,GA4,GA7)含量的变化,并观察其生根发芽情况。【结果】永福报春苣苔叶片插穗生根类型主要为愈伤组织生根型。插穗扦插过程中叶片各种内源性激素呈不同的变化趋势,生长素IAA、IBA和IPA含量整体呈先升后降趋势,细胞分裂素ZT和TZR含量呈下降-上升-下降趋势,ABA含量呈上升-下降-上升趋势,GA1含量呈微降-迅速上升-下降趋势;GA4和GA7含量整体呈下降趋势。相关性分析和主成分分析表明,激素含量的变化均存在一定关联性,主成分因子PC1和PC2的累计贡献率达92.73%,主成分因子PC1中,载荷最高且为正值的因素为IAA,载荷值为0.762;主成分因子PC2中,载荷最高且为正值的因素是ZT和TZR,载荷值分别为0.454和0.329。不定根开始发生阶段IAA和TZR的含量达峰值,其后通过消耗实现不定根的大量生长;ZT在不定根大量发生阶段达到峰值,随后降低。【结论】在永福报春叶片扦插过程中,多种激素协同作用促进扦插生根,IAA、ZT和TZR是永福报春苣苔叶片插穗生根进程中的关键植物激素,对插穗生根进程中多种植物激素含量的变化存在重要影响。

打叶加工中大片率控制对卷烟生产的影响

为探明打叶加工过程中叶片结构控制对卷烟生产的影响,研究了不同大片率的片烟原料对卷烟制丝及卷包生产的影响,其中T1处理的大片率均值为65.49%,T2处理的大片率均值为45.41%,T3处理的大片率均值为33.61%。结果表明:打叶加工过程中大片率过高,制丝环节烟丝缠绕严重,超长丝偏高;当大片率控制过低时,制丝后碎丝率偏高,超出新版卷烟供应规范中的相关规定,不利于后续的卷烟生产;打叶加工过程中的大片率与制丝环节整丝率、长丝率存在一定的正向关系,与碎丝率存在一定的反向关系;打叶加工过程中大片率控制适宜,有利于提升卷制烟支的物理质量,提高卷制烟支质量、吸阻等物理指标的稳定性;就落头倾向而言,各处理片烟卷制常规烟支均优于常规卷烟A,而对细支烟的落头倾向除T1处理外,其他2个处理与对应规格的细支卷烟B相当。因而,在打叶加工中采用适宜的措施,优化加工后成品片烟的叶片结构,能够有效提升打叶加工加工后片烟叶片结构与制丝、卷包工艺的契合度。

丘陵山区榨菜机械化收获关键技术探讨

当前榨菜收获仍大量依靠人工,作业效率低、人高成本高,实现机械化收获是急需解决的问题。基于榨菜收获装备研究现状,指出现有科研样机应用中存在复杂环境适应性差、作业质量稳定性差、经济效益提高不显著等问题,系统分析作业环境、农艺多样性、技术支撑等机械化收获制约因素。提出动力底盘与收获部件动力参数匹配与协同控制技术、自动对行技术、切割高度自动调节技术、仿形除叶技术和关键作业参数实时监测技术等可供榨菜收获机提升改进的建议,以期为丘陵山区榨菜机械化收获装备的研制提供参考。

金花茶回归苗木的生长、光合特性和叶片形态特征

金花茶(Camellia nitidissima)为国家二级重点保护野生植物,具有重要的观赏、药用和科研价值,但其野生资源遭到极为严重的破坏,有濒临灭绝的风险,因此开展金花茶的回归引种,可有效保护该物种。为探究金花茶实生苗、扦插苗回归引种到原生境近7年后在生长和光合生理特性方面的差异,本研究对其生长状况、成活率、光合特性和叶片形态特征等进行测定。结果表明:金花茶回归苗木实生苗比扦插苗具有更大的生长量和更高的成活率;实生苗最大净光合速率(P_(max))、光饱和点(LSP)、表观量子效率(AQY)均显著高于对应点的扦插苗(P<0.05),其光能利用范围也大于对应点的扦插苗;实生苗的叶绿素a(Chl a)、叶绿素b(Chl b)和类胡萝卜素(Car)含量均显著低于对应点的扦插苗(P<0.05),但叶片厚度、海绵组织厚度、中脉导管直径和叶面积则均显著大于对应点的扦插苗(P<0.05);双因素方差分析结果表明,回归点和苗木类型分别对金花茶的株高、地径、成活率、P_(max)、LSP、叶绿素含量和叶面积均有极显著影响(P<0.01)。因此,在开展金花茶回归引种中宜优先选用实生苗种植,并选择具有中等遮阴环境的野外生境进行回归。

适宜毕节烤烟的打叶留茎技术筛选与研究

[目的]为筛选适宜毕节烟区最优的打叶留茎技术。[方法]以烤烟品种云烟87为材料,采用随机区组试验设计方法,比较分析不同留叶数水平下打叶留茎打顶方式与常规方式的烟叶产质量、化学成分和感官质量差异。[结果]第10叶位叶面积以留叶数14片常规打顶(A1)最优,留叶数18片打叶留4个节位茎秆(C3)最差。产量以留叶数18片打叶留4个节位茎秆(C3)最高,产值、上等烟比例和均价则以留叶数16片打叶留2节位茎秆(B2)最优,以留叶数14片常规打顶(A1)最差。主要化学成分协调性以留叶数16片打叶留2节位茎秆(B2)最好,以留叶数14片常规打顶(A1)最差。感官质量评吸得分以留叶数16片打叶留2节位、4节位茎秆(B2、B3)最好,以留叶数14片常规打顶(A1)最差。[结论]留叶数16片打叶留2个节位茎秆和4节位秸秆组合较好。

红花荷嫩枝扦插技术研究

为筛选出多年生红花荷嫩枝扦插繁育的适宜方法,本研究采用L9(34)正交试验设计方法,对插条消毒方法、叶面施肥方法进行扦插试验。结果表明:生根率最高的是处理4(500 mg·L^(-1)多菌灵消毒,不喷施叶面肥);SPAD值最高的是处理8(0.1%高锰酸钾消毒,喷施尿素);处理6(500 mg·L^(-1)多菌灵消毒,喷施磷酸二氢钾)的生根数量最多。方差分析结果表明,消毒方式对存活率及生根率影响最显著,叶面施肥方法对生根率、生根数量和叶绿素含量的影响达到显著水平。因此,试验前用500 mg·L^(-1)多菌灵消毒20 min,消毒后扦插前采用200 mg·L^(-1) NAA溶液浸泡红花荷插条2 h,扦插后不施肥更有利于红花荷嫩枝扦插生根。

剪叶对双季茭白秋茭病害发生及采茭期、产量等主要性状的影响

为明确双季茭白秋茭的适宜剪叶方式,以双季茭品种浙茭3号为试材,于6月15日定植,以不同离地高度设重剪(离地高10 cm)、中剪(离地高25 cm)、轻剪(离地高40 cm)3个剪叶处理,以不剪叶为对照,比较分析不同剪叶处理对胡麻斑病、锈病的控制效果及植株分蘖、采茭期、产量等主要性状表现。结果表明,剪叶后植株病情指数显著降低,对胡麻斑病、锈病防治效果分别为43.95%~49.91%、41.06%~47.69%;重剪、中剪处理提高了植株分蘖数、有效分蘖数及小区产量,净茭率分别显著提高6.53%、5.58%,一级茭率分别显著提高5.43%、4.46%。双季茭秋茭以离地高10~25 cm剪叶为宜。

湖南郴州中低等烟叶分切技术研究

为了研究中低等烟叶的质量分布规律,以2020年桂阳C4F烟叶为材料,通过对选取的标准C4F叶片进行切段,对切后每段样品的物理指标、化学成分、感官质量、配方应用进行测定和评价。结果表明:桂阳C4F烟叶自L 1~L 10每段含梗率逐渐下降,含叶率L 6~L 8段较高,L 1、L 2段含梗率较大,使用价值较小;总糖、还原糖、烟碱含量L 1~L 10逐渐增加,总氮含量在L 1、L 2含量高于其他段,其他段间无显著变化,L 1~L 8段的烟叶感官质量逐步上升,L 9、L 10段有所下降。L 1、L 2烟叶感官质量较差,对整体感官质量有明显负向作用,切后烟叶感官质量提升明显,应用于上等级烟叶模块后可改善香气质和余味,工业适用性进一步提升。

烟叶不同区段质量指标差异研究进展

随着成熟进程的推进,烟叶中的养分在烟株内部会发生迁移,造成烟叶不同区段物质含量存在差异。烟叶不同区段各项质量指标的差异影响其卷烟配方的可用性,研究烟叶不同区段质量指标差异对提高卷烟质量和生产效益具有重要意义。本文综述了烟叶不同区段外观质量、物理特性、化学成分、感官质量等指标差异的研究进展,认为通过合理的分切可以实现烟叶的最优化利用,从而提高烟叶可用性,缓解优质原料紧缺现状。