Effects of cultivation conditions on the diversity of microbes involved in the conversion of rice straw to fodder

To confirm the optimum cultivation conditions for analyzing lactic acid bacterial communities and to provide the cultivation foundation for lactic acid bacterial communities that were used to convert straw into fodder, fermented rice straw was inoculated into 13 different broths. After 48 h of cultivation, pH values, volatile products, and microbial diversity were analyzed. Except for LAB broth, the pH values of the other broths could decrease to approximately 4.5. GC/MS analysis showed that lactic acid in Tomato MRS broth, MRS broth, LAB broth, and Tomato juice broth was higher than that in the other broths. DNA concentration analysis showed that the counts of microbes in Tomato MRS broth were 2.5 times of those in other broths and that tomato juice favored the reproduction of the microbes. Denaturing gradient gel electrophoresis （DGGE） analysis showed that the number of lactic acid bacterial species in HYA broth, Tomato juice broth, and Tomato MRS broth were higher than those in the other broths.

Enhanced production of elastase by Bacillus licheniformis ZJUEL31410:optimization of cultivation conditions using response surface methodology

Sequential methodology based on the application of three types of experimental designs was used to optimize the fermentation conditions for elastase production from mutant strain ZJUEL31410 of Bacillus licheniformis in shaking flask cul- tures. The optimal cultivation conditions stimulating the maximal elastase production consist of 220 r/min shaking speed, 25 h fermentation time, 5% (v/v) inoculums volume, 25 ml medium volume in 250 ml Erlenmeyer flask and 18 h seed age. Under the optimized conditions, the predicted maximal elastase activity was 495 U/ml. The application of response surface methodology resulted in a significant enhancement in elastase production. The effects of other factors such as elastin and the growth factor (corn steep flour) on elastase production and cell growth were also investigated in the current study. The elastin had no significant effect on enzyme-improved production. It is still not clear whether the elastin plays a role as a nitrogen source or not. Corn steep flour was verified to be the best and required factor for elastase production and cell growth by Bacillus licheniformis ZJUEL31410.

Dissipation Kinetics of Chlorpyrifos in Soils of a Vegetable Cropping System under Different Cultivation Conditions

Dissipation kinetics of chlorpyrifos in the near-neutral paddy soils of a vegetable cropping system under greenhouse, screenhouse and field conditions was studied using a rapid analytical method. The recoveries of chlorpyrifos were between 86.5% and 105.5% with relative standard deviations for repeatability between 6.6% and 9.1% at fortification levels of 0.01, 0.1 and 1 mg/kg in the soil. The limit of detection of the method was 0.004 mg/kg and the limit of quantification was found to be 0.01 mg/kg. The dissipation rates of chlorpyrifos followed the first-order kinetics and the half-life was 6.96, 6.04 and 5.20 days in the soil under greenhouse, screenhouse and field conditions, respectively. The dissipation rates of chlorpyrifos in the soil varied with different cultivation conditions. Chlorpyrifos in the soil dissipated slower in a greenhouse and screenhouse than in the open field, which was likely attributed to the hermetic environment in the greenhouse and screenhouse.

Optimization of cultural conditions for thermostable β-1,3-1,4-glucanase production by Bacillus subtilis ZJF-1A5

The optimization of cultural conditions for β glucanase production by Bacillus subtilis ZJF 1A5 was investigated in flask trials. Temperature had great effect on β glucanase production which maximized at optimal temperature of 37℃ and decreased significantly when temperature was over 37℃.Charge quantity affected β glucanase production significantly. Adding oxygen vector N dodecane or acetic ether benefited β glucanase production, but it depended on the concentration and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were the key factors affecting β glucanase production and the cultivation time span to reach the highest β glucanase activity. The optimal cultural conditions for β glucanase production obtained with CCD were as follows: inoculum age and size (16 h, 3.82%(v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37℃ for 50 h. Repeated experimental results accorded with those predicted by a second order polynomial model. The amount of β glucanase, α amylase and neutral protease produced by B subtilis ZJF 1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and increased significantly when cells entered the stationary phase.

Effect of Different Cover Cultivations in Later Summer on Aroma Constituents of Autumn Tea (Camellia sinensis L.)

Tea plants grown under sunshade net and greenhouse are new methods for coping with high- temperature stress in later summer in middle and south China. Aroma is one of the most important flavors and qualities of tea. In this research the cultivar “Longjing-changye” (LJCY) was grown under sunshade net, greenhouse and open field as treatments to study the changes of aromatic substances by using Head Space Solid Phase-microextraction and Gas Chromatography-Mass Spectrometry (HS-SPME/GC-MS). The results showed that tea plants grown under sunshade net and greenhouse had higher content of aroma substances in autumn tea. Those growing conditions are good for improving the contents of the ester and geraniol with floral and fruity fragrance in autumn tea. Moreover, overshadowing in summer is helpful to improve fragrance of fresh tea leaves quality in autumn tea, particularly the 50% sunshade net.

Cannabis Indoor Growing Conditions, Management Practices, and Post-Harvest Treatment: A Review

Cannabis has attracted a new wave of research attention as an herbal medicine. To deliver compliant, uniform, and safe cannabis medicine, growers should optimize growing environments on a site-specific basis. Considering that environmental factors are interconnected, changes in a factor prompts adjustment of other factors. This paper reviews existing work that considers indoor growing conditions (light, temperature, CO2 concentration, humidity, growing media, and nutrient supply), management practices (irrigation, fertilization, pruning & training, and harvest timing), and post-harvest treatment (drying and storage) for cannabis indoor production.

Key Techniques of Cultivation of Stropharia rugosoannulata

Stropharia rugosoannulata is a straw rotting edible fungus that has developed rapidly in recent years.In the process of cultivation,key technologies have a huge impact on its yield.The key techniques for the cultivation conditions and modes of S.rugosoannulata were summerized to promote the realization of stable and high yield of S.rugosoannulata.

我国设施园艺病虫害发生特点与绿色防控策略

我国设施园艺发展迅速,对促进农业现代化、乡村振兴和都市农业发展具有重要作用。本文结合我国设施园艺产业的发展现状,总结设施环境下病虫害发生特点,并从农业防治、物理防治、生物防治、生态调控、生物技术和科学用药等方面概述了病虫害防治技术,最后对设施园艺病虫害防治提出建议,以期为我国设施园艺的健康可持续发展提供参考。

基于耕地资源质量分类监测的土壤条件变化对粮食产量的影响——以河南省兰考县为例

为突出土壤条件变化对粮食产量的影响,采用趋势分析法和对比分析法,以兰考县耕地资源质量分类监测工作为例,分析土壤监测样点不同年份的土壤条件变化对当地粮食产量造成的影响。研究表明,土壤有机质含量的增加和土壤pH在合理范围内的增加都能够提升粮食产量。建议以测土配方施肥为基础,增加有机肥的使用量,提升土壤有机质含量,并针对当地土壤的实际情况和主要作物类型,提出有针对性的改良土壤pH的措施,以提升粮食产量。

基于广泛靶向代谢组学解析不同树龄及栽培条件的野酿2号腺枝毛葡萄类黄酮差异

【目的】基于广泛靶向代谢组学分析不同树龄及栽培条件的野酿2号腺枝毛葡萄类黄酮差异代谢物情况,为提升葡萄及葡萄酒品质提供理论参考依据。【方法】以不同树龄及栽培条件(地域和架式)的野酿2号腺枝毛葡萄为试材,测定粒重、pH、可溶性固形物、可滴定酸含量及亮度值(L^(*))、红—绿色度值(a^(*))、黄—蓝色度值(b^(*)),并利用超高效液相色谱—串联质谱仪对其成熟期葡萄果实进行广泛靶向代谢组学分析。【结果】不同树龄及栽培条件的野酿2号腺枝毛葡萄理化指标之间存在不同程度的差异,栽培地域对葡萄果实理化指标影响较大,栽种于相思湖葡萄示范基地的果实成熟度更好,但果粒较小、果皮颜色较浅;栽培架式及树龄对葡萄果实的粒重影响较小,对糖酸含量影响较大;同一地域采用篱架栽培的葡萄果实较棚架栽培成熟度更好,且树龄越大,果实成熟度越好。从不同树龄及栽培条件的成熟期葡萄果实中共鉴定出11类789种代谢物,其中黄酮类最多,为187种。12个样品中共存在271个差异代谢物,共聚为7个类群,黄酮类化合物在各亚类中占比最高,特别是第Ⅱ类群,占比高达59%,其次是第Ⅰ类群,占比为49%。利用差异代谢物能明确区分来自不同地域、架式和树龄的葡萄果实样品,其中地域样品间的差异最大,且黄酮类化合物是造成差异的最主要化合物。明阳双季葡萄示范基地栽培较相思湖葡萄示范基地栽培更利于杨梅素、槲皮素、表儿茶素及甲基花翠素等类黄酮化合物的积累,5年树龄较8年树龄更有利于促进山柰酚、儿茶素和花青素的积累,而棚架栽培较篱架栽培更利于黄烷-3-醇、花青素双糖苷和花葵素双糖苷的积累。可溶性固形物含量与黄酮醇中的槲皮素和杨梅素含量呈显著负相关,L^(*)和a^(*)均与杨梅素呈显著负相关。【结论】不同树龄及栽培条件的野酿2号腺枝毛葡萄果实类黄酮代谢物含量存在差异,其中地域影响最明显。

水稻垩白形成机制的研究进展

垩白是评价水稻外观品质的重要指标之一,是一种严重影响稻米碾磨、外观及食味品质的不良性状,对水稻的市场价值评估起到重要作用。本研究主要总结了水稻垩白的形成受生理机制、遗传机制和环境因素的影响,同时指出目前育种工作中改良垩白性状所存在的难点问题,并根据目前的研究成果与相关技术的发展,提出一些改良意见,为优质稻米的生产提供一定的研究基础。

丹东蓝莓种植区气候条件影响分析

利用1991~2020年地面气象观测数据和蓝莓物候观测资料,对丹东蓝莓种植适宜区气象指标进行对比分析,研究温度、水分、光照等气象条件对蓝莓生长的影响,分析各个蓝莓主要种植县的气象条件分布特征。结果表明:丹东蓝莓主要种植区域气候资源较好,除了冬季气温偏低外,基本满足蓝莓生长所需的气候条件。30年间4月平均气温振幅较大,需要防范春季倒春寒对蓝莓产业影响;受气候变化影响,降水集中时段有后延趋势,对于早熟和中熟品种蓝莓,在年景偏差情况下,需要加强水分管理,而对晚熟品种需要做好强降水和连阴雨等灾害性天气防范;光照条件完全满足蓝莓生育期所需,中部地区更有利于蓝莓种植。研究成果将为蓝莓产业发展提供参考。

培养条件对丝状微藻克里藻生长与亚油酸合成的影响

为开发亚油酸生产新资源,对筛选获得的一株丝状微藻克里藻,考察培养基氮浓度、培养基磷浓度、光强、培养温度和环境pH对其生长、氮消耗、油脂含量和油脂脂肪酸组成的影响。结果表明:培养基氮浓度对克里藻生长没有明显影响,但高氮不利于油脂和不饱和脂肪酸的合成;培养基磷浓度过低会抑制细胞生长,过高对细胞有毒害作用;适当提高光强有利于细胞生长,但对细胞内油脂含量影响不大,低光强培养有利于亚油酸等不饱和脂肪酸的合成;培养温度对克里藻生长与油脂积累影响不大,低温培养有利于亚油酸的合成;环境pH对细胞生长、油脂积累和亚油酸合成影响明显,pH 6.0~7.5的弱酸-中性条件下细胞生长最快,油脂含量更高;控制初始氮浓度3~6 mmol/L、磷浓度0.115~0.230 mmol/L、光强100~300μmol/(m^(2)·s)、培养温度15~30℃、环境pH 7.5左右,克里藻细胞可积累42%左右的油脂,油脂中亚油酸含量在65%~75%。综上,丝状微藻克里藻是一种有潜力的亚油酸生产新资源。

桑椹菌核病菌的分离鉴定及室内药剂筛选

【目的】桑椹菌核病是桑果上的一种毁灭性病害,对果桑产业的健康发展和产量稳定构成了严重的威胁。分离鉴定引起江西省乐安县桑椹菌核病的病原菌并筛选抑制其菌丝生长的生物农药,为后续研究该病绿色防控技术提供理论依据。【方法】利用组织分离法和柯赫氏法则对江西省乐安县的发病桑椹进行病原分离和致病性测定;采用形态学和分子生物学手段对分离到的病原菌进行鉴定并优化其培养条件;采用含药平板法测定7种生物农药对病原菌的抑制效果。【结果】从发生桑椹菌核病的种植地采集的菌核分离出的8株真菌在PDA培养基上培养特征一致,以菌株JH21为代表对其ITS和RPB2序列扩增测序,经过同源比对确定JH21为核地杖菌(Scleromitrula shiraiana)。该菌的菌丝在pH为6的绿豆葡萄糖琼脂培养基(MBDA)上12 h/12 h光暗交替、20~25℃培养时生长较好。室内药剂筛选结果表明,0.3%四霉素水剂和0.3%丁子香酚可溶液剂对核地杖菌有较好抑制作用,其EC50分别为0.078μg/mL、0.667μg/mL。【结论】研究确定了在江西省乐安县种植园中的桑椹主要受到由核地仗菌侵染引起的缩小性菌核病的威胁。四霉素和丁子香酚作为生物农药具有绿色、安全的特点,在防治桑椹菌核病方面具有应用潜力。

建环专业洁净空调人才培养改革路径探析——以桂林航天工业学院为例

以芯片制造、生物医药为代表的高新技术产业迅猛发展,有效释放了对洁净室的潜在需求。建筑环境与能源应用工程专业作为研究洁净空调的主要专业之一,在洁净室设计、施工及运维过程中发挥主导作用,但是目前大多数高校建筑环境与能源应用工程专业人才培养体系在洁净空调方面存在较大缺陷,造成人才培养与产业需求不匹配。基于以上现实问题,以桂林航天工业学院建筑环境与能源应用工程专业为例,从人才培养目标、课程体系、教师队伍等方面探索了洁净空调人才培养体系的改革路径,为建筑环境与能源应用工程专业可持续发展注入新动力。

暗褐网柄牛肝菌栽培料的筛选

牛肝菌栽培一直是食用菌生产领域的研究难点,适宜的栽培料是菌丝体生长和子实体形成的重要保障。通过测定暗褐网柄牛肝菌的菌丝长势和栽培过程中理化指标以及胞外酶活性,筛选该牛肝菌菌丝体生长的最佳栽培基质。结果表明,通过测定菌丝体长势,初筛得到5种栽培料配方,分别为C_(1)(杨木屑99%、生石灰1%)、C_(3)(橡木屑99%、生石灰1%)、Y_(1)(杨木屑50%、玉米芯24.5%、麦麸皮24.5%、生石灰1%)、Y_(2)(杨木屑50%、玉米芯24.5%、棉籽壳24.5%、生石灰1%)、X2(橡木屑50%、玉米芯24.5%、棉籽壳24.5%、生石灰1%)。在栽培过程中,Y_(1)和Y_(2)栽培基质总有机碳、全氮含量在菌丝体生长时期均处于较高水平,且营养消耗速率快,Y_(2)栽培基质中羧甲基纤维素酶、半纤维素酶、淀粉酶、蛋白酶和漆酶活性均较显著高于其他组。由此可见,Y_(2)栽培料基质更适合暗褐网柄牛肝菌菌丝体的生长。试验结果为暗褐网柄牛肝菌菌丝体生长提供了理论依据,为暗褐网柄牛肝菌栽培奠定了重要理论基础。

不同栽培模式及生态条件对小麦粒重和粒型的影响

为研究不同栽培模式及生态条件对小麦粒重和粒型的影响,本研究以8个扬麦系列和宁麦系列弱筋小麦品种及2个中筋小麦品种为材料。测定分析参试小麦品种在不同年份、不同试点及不同栽培模式的粒重和粒型的稳定性及差异性。结果表明,小麦粒重和粒型既受品种的遗传特性控制,也受栽培模式及生态条件的影响。千粒重在栽培模式间的差异不显著,参试品种粒型性状在不同试点、年份及栽培模式的变化趋势基本一致。弱筋小麦品种扬麦15和扬麦24及中筋品种扬麦28不同试点、年份及栽培模式的千粒重均较高、粒型比较理想。综上,要获得理想的小麦粒重和粒型,除选用粒型大的品种外,还应选择适宜小麦生长的生态地区,配以合适的栽培模式,保证小麦灌浆期水肥充足。

栽培密度对落叶松人工林生长的影响

为探究栽培密度对落叶松人工林生长的影响,以兰州地区的落叶松人工林为研究对象,考察不同栽培密度下落叶松生长性状及环境状况的差异,探讨栽培密度对落叶松人工林生长的影响。结果显示,不同栽培密度下落叶松种树高、胸径、冠幅、郁闭度、枯落物厚度以及灌草盖度均受到显著影响。随着密度的增加,落叶松树高呈现出先增后降的趋势,处理3的树高最高为18.13 m;胸径呈现逐渐降低的趋势,处理1胸径最大为16.83 cm;冠幅呈现逐渐降低的趋势,这与胸径变化趋势相同,冠幅最大的为处理1(4.16 m),最小的为处理4(2.61 m);落叶松人工林郁闭度呈增加趋势,处理4的郁闭度最高为87.25%;枯落物厚度呈现逐渐增加的趋势,处理4枯落物厚度最大为8.36 cm;灌草盖度呈现出先增后降的趋势,处理3的落叶松灌草盖度最大为72.96%。

麻栎在郴州石漠化地区的栽培试验

研究了不同造林树种在石漠化地区的生长情况和不同海拔高度及土壤母质类型下麻栎的生长情况,结果表明:在郴州石漠化地区,麻栎-柏木混交林中麻栎的树高生长量(210.87~216.87 cm)及地径生长量(22.57~28.80 mm)大于柏木的树高生长量(148.60~188.60 cm)及地径生长量(20.00~22.24 mm);同样,麻栎-光皮树混交林中麻栎的树高生长量(244.83~250.47 cm)及地径生长量(30.34~34.40 mm)也大于光皮树的树高生长量(180.80~235.60 cm)及地径生长量(20.49~29.10 mm),从总体上看麻栎的生长情况表现显著优于柏木及光皮树,而后二者是郴州石漠化地区复绿造林的常用树种,这也表明麻栎适合于郴州石漠化地区的造林推广。另外,栎的树高和地径生长量受到海拔高度和土壤母质类型等立地条件的显著影响,表现为海拔高度越高生长量越小、石灰岩优于砂砾岩优于花岗岩,而对地径生长量的影响会弱于对树高生长量的影响。

仙客来枯萎病病原菌产孢培养基筛选及培养条件优化

为了获得高浓度的仙客来枯萎病病原菌的孢子悬液,通过对不同营养培养基进行初筛,再以初筛营养成分进行正交试验,得到最佳营养配比,进一步通过单因素试验对培养基的pH和培养温度进行筛选。结果表明,马铃薯、绿豆、蔗糖为仙客来枯萎病病原菌产孢培养基的最佳营养成分,最佳配比为绿豆5.0%、蔗糖0.5%、马铃薯20%,培养基最佳pH为6,最佳培养温度为30℃。研究结果明确了仙客来枯萎病病原菌的产孢条件,为仙客来枯萎病的感病机理、防治技术及孢子萌发抑制等研究奠定基础,同时对指导实际生产中科学管理、综合防治病害具有重要意义。