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1.
The varied diet of European starlings (Sturnus vulgaris L.) can present challenges when working with starlings in experimental testing and holding situations and should be taken into account when testing repellents applied to food. Our purpose was to evaluate an anthraquinone-based repellent (Arkion Life Sciences, New Castle, DE, USA; active ingredient 50% 9,10-anthraquinone; hereafter anthraquinone) and SucraShield™ (Natural Forces, Davidson, NC, USA; active ingredient 40% sucrose octanoate esters) repellent for non-lethal protection of specialty crops (i.e., fruit, sweet corn) and grains. Our objectives were to evaluate (1) laboratory efficacy of anthraquinone applied topically to blueberries and sweet corn, (2) laboratory efficacy of anthraquinone applied to two pellet matrices, and (3) laboratory efficacy of SucraShield™ as a chemical repellent for European starlings. We found that anthraquinone was not an effective repellent for blueberries or sweet corn, although consumption of each matrix varied potentially due to sucrose content. Anthraquinone was an effective repellent on CU Bird Carrier pellets with 6275 ppm needed to achieve 80% repellency, whereas up to 35,000 ppm anthraquinone was not effective when the anthraquinone was not topically applied. SucraShield was not an effective repellent for starlings and in fact increased consumption of CU Bird Carrier as concentration increased. 相似文献
2.
Dale L. Nolte James P. Farley Dan L. Campbell Gisela M. Epple J. Russell Mason 《Crop Protection》1993,12(8):624-626
Mountain beaver (Aplodontia rufa) damage to trees in the Pacific Northwest is economically serious. At present, few strategies are available to control damage, and new chemical repellents are being sought. Samples of two preferred plants, Douglas fir (Pseudotsuga menziesii) and salal (Galtheria shallon), were treated with mink urine, coyote urine, o-aminoacetophenone, or denatonium benzoate and presented to mountain beavers. All treatments reduced clipping (p < 0.05) of salal, but mink and coyote urines were most effective. Mink and coyote urines were the only treatments to significantly reduce clipping (p < 0.05) of Douglas fir. 相似文献
3.
An alternate-row treatment of the bird repellent methiocarb (CA chemical name 3, 5-dimethyl-4-(methylthio)phenyl methylcarbamate; Mesurol® was evaluated for protecting entire cherry orchards from damage by European starlings, American robins, house finches, common grackles and other birds. Half of each orchard was randomly selected for treatment with methiocarb (1·7 kg/ha) applied to trees in every other row. The other half of each orchard was used as a control. Estimated loss of cherries to birds at the time of damage assessment was significantly lower in the six partially sprayed blocks (6·5%) than in the six unsprayed, control blocks (8·8%) (P = 0·03). However, the level of bird damage and the magnitude of the reduction were insufficient to provide a favourable benefit:cost ratio: there was a return of only $0·80 in cherries saved for every $1·00 spent on application and chemical costs. The overall lower damage in the partially sprayed blocks appeared to result primarily from reduced feeding by birds in the sprayed trees, which averaged 4·6% loss compared with 8·4% loss for unsprayed trees within the same block (P = 0·22). That this difference was not statistically significant indicates that birds had to sample a substantial number of berries before discriminating between sprayed and unsprayed fruit. It is not clear how birds detected berries sprayed with the repellent. Suggestions for evaluating other partial treatments of bird repellents in cherry orchards are discussed. 相似文献
4.
The present experiments were designed to identify inexpensive substitutes for
-pulegone, an effective vertebrate repellent. In experiment 1, European starlings (Sturnus vulgaris) were presented with
-pulegone and 12 additional menthone derivatives in one-cup tests. No derivative was as effective as
-pulegone. In experiment 2, starlings were presented with
-pulegone,
-pulegone and
-pulegone in onecup tests.
-pulegone was as aversive as
-pulegone, and both
-pulegone and
-pulegone were more aversive than
-pulegone. More extensive evaluation of
-pulegone as a vertebrate repellent appears warranted. 相似文献
5.
Effects of formic acid, formaldehyde and two levels of tannic acid on changes in the distribution of nitrogen (N) and plant enzymatic activity during ensilage of lucerne (Medicago sativa) were studied. Lucerne [300 g dry matter (DM) kg?1 forage] silages were prepared untreated (control) and with formic acid (4 g kg?1 DM), formaldehyde (1 g kg?1 DM) and two levels of tannic acid (20 and 50 g kg?1 DM) as additives. Inhibition of proteolysis by formic acid was more effective than the other additives during the first 7 d of ensiling. Tannic acid was as effective at inhibiting production of non‐protein‐N, ammonia‐N and free amino acid‐N as formic acid and formaldehyde. However, increased concentrations of non‐protein‐N and free amino acid‐N in silage from day 1 to 35 of ensiling were less with the higher level of tannic acid than that in the control and other additive‐treated silages. Carboxypeptidase lost its activity slowly with increasing time of ensiling. At day 2, it still had 0·79 of the original activity in the control silage. After 21 d of ensiling, high levels of carboxypeptidase activity, proportionately 0·41, 0·49, 0·10, 0·35 and 0·30 of the original activity, remained in the control silage, and silages made with formic acid, formaldehyde, and low and high levels of tannic acid respectively. There were higher levels of activity of acid proteinase in formic acid‐treated silage than in the control silage until day 2 of ensilage indicating that the reduction of proteolysis by formic acid was probably due to acidifying the forage below the pH optima of plant protease. Aminopeptidase activity in all silages declined rapidly after ensiling. 相似文献
6.
Quinoa (Chenopodium quinoa Willd) is a Latin American food staple readily available in large quantities in Peru, Bolivia and Ecuador. The outer husk of the grain is removed prior to consumption to reduce its bitter taste. At present, quinoa husks are considered as a by-product with no commercial value, despite its high content of triterpenoid saponins (20–30%). Due to this, the present work was undertaken to test if quinoa saponins have antifungal properties against Botrytis cinerea and if this activity is enhanced after alkaline treatment, since recent reports indicate that alkaline treatment of quinoa saponins increase their biological activity. Six products were tested against B. cinerea: (1) non-purified quinoa extract, (2) purified quinoa extract, (3) alkali treated non-purified quinoa extract, (4) alkali treated purified quinoa extract, (5) non-purified quinoa extract treated with alkali but without thermal incubation and (6) purified quinoa extract treated with alkali but without thermal incubation.
Untreated quinoa extracts showed minimum activity against mycelial growth of B. cinerea. Also, no effects were observed against conidial germination, even at 7 mg saponins/ml. However, when the saponin extracts were treated with alkali, mycelial growth and conidial germination were significantly inhibited. At doses of 5 mg saponins/ml, 100% of conidial germination inhibition was observed, even after 96 h of incubation. Fungal membrane integrity experiments based on the uptake of the fluorogenic dye SYTOX green showed that alkali treated saponins generate membrane disruption, while non-treated saponins had no effects.
The higher antifungal activity of alkaline treated saponins is probably due to the formation of more hydrophobic saponin derivatives that may have a higher affinity with the sterols present in cell membranes. 相似文献
7.
Altering the relative sugar content in fruit is a potential alternative to chemical, aural and visual repellents to control bird damage to cultivated fruit crops. Some frugivorous birds, such as the American robin (Turdus migratorius), lack the digestive enzyme sucrase, and therefore cannot digest sucrose. It was predicted that robins would avoid consumption of foods that contain sucrose. When offered sweetened agar cubes that contained glucose, fructose, sucrose, or a hexose mixture, total consumption was significantly lower and faecal sugar concentration higher in the sucrose tests. In tests involving two sugars, mean total consumption was reduced when sucrose was eaten. Development of high-sucrose fruits warrants further investigation as a means to mitigate bird damage to certain fruit crops. 相似文献
8.
A specifically-synthesized water-soluble photochromic acid dye has been applied by screen printing on to silk, wool and nylon.
The influence of processing parameters and the nature of the substrate on the photochromic response of the printed materials
has been evaluated using specifically-developed colour measurement methodology. The printed substrates show photochromic colour
change from weakly coloured to an intense blue colour under sunlight or UV irradiation. In most cases, the photochromic colour
build up is higher on wet substrates than after drying. Computer aided molecular modelling techniques have been used to explain
aspects of the photochromic behaviour. 相似文献
9.
Between November 1998 and March 1999, bands of nymphs of Locusta migratoria were aerially treated using a ULV oil formulation of strain FI-985 of Metarhizium anisopliae var. acridum. At a dose of 3–4×1012 conidia/ha, there was <10% survival of locusts in treated sorghum crops, open grassland or open woodland with grass. Decline was less at lower doses or in dense woodland. During the first week after treatment, bands showed little change in numbers, but then rapidly declined in size and rate of movement. The decline was slower where vegetation was tall or dense, or where bands were large and moved out of the treated area a few days after spraying. In areas where bands were treated with Metarhizium, populations were suppressed in that few adult swarms formed. Adjacent untreated areas had many adult swarms which had to be controlled using chemical insecticides. Preventive locust control, as currently practised in Australia, involves beginning treatment when areas of band and swarm are small and the potential for direct damage limited. The clear demonstration that Metarhizium can suppress small local populations of L. migratoria indicate that it could be a valuable component of preventive control programmes against this species. The delay in mortality when treating with Metarhizium would be no impediment to its use in such programmes. 相似文献
10.
R. W. Summers 《Crop Protection》1985,4(4):520-528
A study was carried out on the behaviour of starlings (mainly juveniles) which are pests in cherry orchards where they eat ripening fruit. Observations on 17 radio-tagged starlings during the cherry-picking season showed that most individuals continued to feed in the orchards on consecutive days despite the use of a variety of scarers. Distress calls of starlings played through loudspeakers were effective in that they temporarily scared starlings, but birds returned during the periods when no distress call was played. However, starlings no longer responded to these distress calls after the period between days 7 and 13. Captive starlings could not maintain their weight on a diet of cherries and the maximum daily intake was 25 cherries, amounting to 1·5 times the bird's own weight. The length of time spent in the orchards by radio-tagged birds (on average 2·8 hours) was far longer than the time needed to eat 25 cherries. It is concluded that the present arrangement of scarers was inefficient and that the netting-in of an orchard would be more effective. 相似文献
11.
由尖孢镰刀菌古巴专化型热带4号生理小种（Fusarium oxysporum f. sp. cubense tropical race 4, TR4）引起的香蕉枯萎病严重阻碍我国香蕉产业的绿色可持续发展。外源水杨酸（SA）处理能诱导香蕉体内SA合成及信号传导途径关键酶基因上调表达,激活香蕉植株内系统获得抗性,增强对各种生物和非生物胁迫的抵抗能力,在此基础上,本研究对香蕉感病品种‘巴西蕉’和抗病品种‘农科1号’进行SA诱导处理,随后接种TR4,结果显示2个品种的病情指数均降低。为了进一步探究水杨酸信号途径下游的苯丙烷类途径在SA诱导的香蕉植株抗病过程中的作用,本研究运用实时荧光定量PCR技术（RT-qPCR）,对SA处理的感病品种‘巴西蕉’和抗病品种‘农科1号’中苯丙烷类途径关键基因的表达情况进行分析,结果发现分支途径中常规苯丙烷类途径关键酶基因C4H和4CL、木质素合成途径关键酶基因CAD和CCoAOMT、黄酮类物质生物合成途径关键酶基因CHS和CHI,对SA处理和TR4接种均有响应。在仅接种TR4的情况下,‘巴西蕉’相关基因主要表现为显著下调表达,而‘农科1号’相关基因主要表现为上调表达;仅用SA处理时,2个品种的C4H和4CL被诱导上调表达;SA处理并接种TR4,2个品种C4H和4CL依然保持上调表达的趋势,变化幅度在‘农科1号’中偏高;‘巴西蕉’CAD经SA诱导上调表达,但在接种TR4后,CAD相对表达量降低,而‘农科1号’CAD被SA诱导显著上调表达,SA和TR4共同作用下,表达水平亦显著升高;‘巴西蕉’CCoAOMT被TR4诱导显著上调表达,在SA处理并接种TR4的‘巴西蕉’植株中也表现为上调表达,‘农科1号’CCoAOMT在SA处理或SA、TR4共同作用下表现为强烈上调表达;CHS和CHI在SA处理的2个品种中主要表现为上调表达,SA和TR4双重作用下,依然表现为上调表达。结果表明外源SA处理可诱导感病和耐病香蕉根组织中苯丙烷类途径关键酶基因上调表达,该途径在SA诱导的香蕉抗枯萎病过程中起着重要作用。 相似文献
12.
Summary Tubers of twelve cultivars ofSolanum tuberosum L., with a varying content of reducing sugars (0.49–2.30 g/100 g fresh weight), were sliced and fermented for up to 48 h
by lactic acid bacteria in a brine of 1.5% NaCl, prior to frying. The content of reducing sugars decreased by 80 to 100%,
depending on the initial sugar level. Colour of chips was measured using the CIE (1976) L*a*b* colour system, where L* is lightness, a* is redness and b* is yellowness of the material and by IBVL colour cards, photographs used for grading the colour of potato chips. L*-values were the best measurement of chip colour. The scale of the IBVL colour cards was too narrow (scale 1–9) for this study,
as chips from eight of the cultivars were scored lighter than IBVL 9 after 48 h of fermentation.
Lighter coloured chips significantly correlated with lower contents of reducing sugars. The sugar content decreased as fermentation
time increased. Fermentation time can thus be used to control potato chip colour, and all the cultivars tested can be used
for production of chips with regard to colour. 相似文献
13.
为充分利用山胡椒的果、茎、叶,本研究通过GC-MS方法比较它们的化学组成差异,综合评价各自的特点,以期为拓宽山胡椒的应用提供依据。对采自云南怒江州3个地区山胡椒的果、茎、叶均采用二氯甲烷超声进行提取相应挥发性成分,通过GC-MS分析比较二氯甲烷提取物中各挥发物成分的含量差异,以期发现具有潜在应用价值的化学成分。结果发现,不同地区的山胡椒所含挥发物种类和含量均有差异,同地区山胡椒的不同部位之间所含挥发物种类和含量差别大。亚坪山胡椒的果、茎、叶中存在挥发物种类更多、更为丰富,各含有254、66、60个挥发物,金顶山胡椒的果、茎、叶中各含有192、60、76个挥发性化合物,姚家坪山胡椒的果茎叶各含有251、43、55个挥发物;3个地区山胡椒的果实间共同挥发物有43个,茎之间的共同挥发物有21个,叶之间的共同挥发物有24个。山胡椒的果实中醛类含量最多,其次含量较多的是有机酸类化合物;茎中多数为酯类化合物,其次是烷烃类化合物,叶片中多数为烷烃类、烯烃类化合物。在金顶和亚坪地区的山胡椒中,棕榈酸、正癸酸、月桂酸、油酸和亚油酸含量较高;在姚家坪地区的山胡椒中,4,8-dimethyl-3,7-nonadien-2-ol、epoxy-linalooloxide、geranic acid、(Z)-3,7-二甲基-2,6-辛二烯醛、2-甲基-5-(1-甲基乙烯基)环己酮、3-甲基-2-环己烯-1-酮这几种物质含量较高。上述物质在化工、医药等领域都有较大应用,3个地区山胡椒不同部位化学成分及含量的差别会导致其在应用上存在差别,该研究将为云南怒江州不同地区山胡椒果茎叶的开发利用提供一定科学依据。 相似文献
14.
为充分利用3种姜科植物的地上茎叶部分,本研究采用GC-MS和LC-MS方法比较了其化学组成差异,综合评价各自的特点,以期为拓宽姜科植物茎叶的应用提供依据。对采自云南怒江州的3种姜科不同香料植物草果、春砂仁、艳山姜地上部分的茎、叶分别采用80%甲醇、正己烷超声进行提取相应化学成分。采用LC-MS方法分析比较甲醇提取物中主要的6种姜科植物中具有抗癌抗炎等活性成分的含量差异,以评价地上部分在药理应用上的潜力。结果发现,各活性化合物在3种姜科植物茎叶中的含量均差异显著,春砂仁和艳山姜的茎中表儿茶素含量丰富,而草果茎以庚二醇为主。草果和艳山姜叶中奎尼酸和莽草酸含量较高,草果叶片中还有较低含量的庚二醇,艳山姜叶中有远高于另外两者的表儿茶素,而春砂仁叶片中仅检测到较低含量的奎尼酸。采用GC-MS方法分析正己烷提取物,综合分析3种姜科植物茎、叶的整体化学成分,以期发现具有潜在应用价值的化学成分。结果发现,三者茎、叶整体化学成分在数量和种类上均有明显差异。在春砂仁茎叶中发现有多种很高含量的香料成分或前体物质,如龙涎酮、桃金娘烯醇、β-蒎烯、法尼基酮等物质。在艳山姜茎叶中发现有较高含量的维生素E和去甲氧基醉椒素等活性物质。草果叶片中也含有一定量的己酸。上述物质在化工、医药等领域都有较大应用,该研究将为3种姜科植物茎叶的开发利用提供一定科学依据。 相似文献
15.
I. A. Adeyemi E. O. Soluade 《Plant foods for human nutrition (Dordrecht, Netherlands)》1993,44(3):213-220
Pawpaw-ogi was evaluated for proximate and chemical composition, amylograph pasting viscosity, colour and acceptability. The addition of pawpaw to maize ogi slurry had no significant effect on protein and fat contents nor on amylograph pasting characteristics but resulted in significant increases in ash, ascorbic acid, sugars and mineral contents. The Munsell colour notations indicated that the addition of pawpaw improved the colour of ogi. Taste panel evaluation showed that both the powder and porridge of pawpaw-ogi were acceptable. 相似文献
16.
Coloured potatoes (Solanum tuberosum L.) rich in anthocyanins are gaining increasing interest on the markets, mainly due to beneficial health effects. Potato
varieties containing colour pigments are therefore utilized more and more in actual breeding programmes. In this study, 10
purple-fleshed potato cultivars were compared in their resistance to soft rot caused by Pectobacterium carotovorum (Pc) with 10 white/yellow-fleshed potato cultivars. The results revealed that coloured potato cultivars exhibited on average
better resistance to soft rot than white/yellow-fleshed potato cultivars. On tuber halves of purple-fleshed cultivars, the
extent of rotting caused by Pc was on average 28.6% lower than on white/yellow-fleshed cultivars. The greater resistance of
coloured potatoes coincided with the presence of anthocyanins, higher concentrations of soluble phenols and elevated polyphenol
oxidase activity in tuber tissue. These three components were significantly correlated with the extent of rotting caused by
Pc. However, coloured and white/yellow-fleshed cultivars were not very different in phenylalanine ammonia-lyase and peroxidase
activity. There were also no significant differences in concentrations of dry matter, starch, crude protein and glycoalkaloids.
Key findings reveal that total soluble phenols and anthocyanins contributed crucially to resistance expression in tuber tissue
of coloured potato cultivars. 相似文献
17.
了解不同植物对植食性昆虫生物学特性的影响是昆虫-植物互作研究的基础,对制定有效的害虫防控策略具有重要意义。入侵害虫草地贪夜蛾（Spodoptera frugiperda）可能危害的植物多达353种,但大多数寄主植物对其生物学特性的影响尚不清楚。采集植物新鲜叶片饲喂植食性昆虫幼虫是研究的通用方法,而此方法受气候、地理位置、植物生长周期等条件的限制。以玉米（Zea mays）为参照,选取玉米农田及其周边的6种作物和杂草为试验材料,包括大豆（Glycine max）、豇豆（Vigna unguiculata）、番薯（Ipomoea batatas）、艾草（Artemisia argyi）、油麦菜（Lactuca sativa）和黄瓜（Cucumis sativus）。将上述植物的新鲜叶片统一采集、磨成粉末,按1%比例掺入人工饲料中,分别用这些饲料喂养草地贪夜蛾幼虫,观测其存活（幼虫存活率、化蛹率、羽化率）、生长（幼虫增重、蛹重、相对生长率）、发育历期（幼虫期、预蛹期、蛹期）和食物利用情况（相对消耗率、近似消化率、食物转化率、消化转化率）等,探究草地贪夜蛾取食这7种植物后的生物学特性。为验证植物叶片粉末饲料喂养方法的可行性,同时采集上述植物的新鲜叶片分别喂养草地贪夜蛾幼虫。结果显示大豆、豇豆是草地贪夜蛾适宜的寄主植物;而番薯、艾草、油麦菜对草地贪夜蛾的生长发育具有抑制作用,若将其运用于玉米间作系统中,可减轻草地贪夜蛾的为害。运用层次分析法建立指标评价体系进行量化评分,结果表明,植物粉末饲料和新鲜叶片喂养的效应一致,且前者限制条件少、操作简便,可较好地评估农田植物对草地贪夜蛾生物学特性的影响。 相似文献
18.
Bradley N Metz Priyadarshini Chakrabarti Ramesh R Sagili 《Journal of insect science (Online)》2021,21(6)
Honey bee larvae are dependent on the social structure of colony for their provisioning and survival. With thousands of larvae being managed collectively by groups of foragers (collecting food resources) and nurse bees (processing food and provisioning larvae), coordination of colony efforts in rearing brood depends on multiple dynamic cues of larval presence and needs. Much of these cues appear to be chemical, with larvae producing multiple pheromones, major being brood ester pheromone (BEP; nonvolatile blend of fatty acid esters) that elicits both short-term releaser effects and long-term primer effects. While BEP can affect colony food collection and processing with the signaling of larval presence, it is unclear if BEP signals individual larval needs. To understand this aspect, in a series of experiments we manipulated larval feeding environment by depriving larvae from adult bee contact for 4-h period and examined (1) nurse bee interactions with contact-deprived and nondeprived larvae and larval extracts; (2) forager bee responses to contact-deprived and nondeprived larval extracts. We also characterized BEP of contact-deprived and nondeprived larvae. We found that nurse honey bees tend to aggregate more over contact-deprived larvae when compared with nondeprived larvae, but that these effects were not found in response to whole hexane extracts. Our analytical results suggest that BEP components changed in both quantity and quality over short period of contact deprivation. These changes affected foraging behavior, but did not appear to directly affect nursing behavior, suggesting that different chemical cues are involved in regulating nursing effort to individual larvae. 相似文献
19.
Antagonistic bacteria were evaluated for their effectiveness in postharvest control of grey mould on fresh-market tomatoes. Grey mould was reduced in fresh-market tomatoes treated with antagonists and artificially inoculated with Botrytis cinerea, and stored at 20 °C for at least 7 days. One strain, 5PVB (Bacillus amyloliquefaciens) was particularly effective. This strain apparently did not produce extracellular antibiotic substances, yet was highly active against the pathogen on both mature-green and red tomatoes. Treatment with 5PVB before storage at 10 °C showed only fungistatic activity against grey mould. Chilling-injured mature-green tomatoes were more susceptible to B. cinerea. On chilled fruits the bacterial antagonist completely controlled the pathogen if the treatment was applied immediately after storage at 2 °C. In fermentation tests on four industrial waste materials, B. amyloliquefaciens grew well and maintained its antagonistic activity when grown in two of them. In pilot experiments with wounded fruits dipped in the bacterial cell and pathogen suspension, the development of decay was effectively inhibited. 相似文献
20.
Emergence and plant performance were equivalent when peanut seed was treated with either a standard dust or with mixtures of liquid (suspension concentrate) formulations of fungicides applied at rates required to control soil- and seed-borne fungi. Liquid formulations do not pose the health and mechanical problems associated with dusts, so their use should be encouraged and adopted. A suitable treatment consists of a combination of captan 300g/l, dicloran 300g/l, an oil extender and rhodamine dye in acetic acid at 188, 247, 341 and 4 · 6 ml respectively per 100 kg of seed. 相似文献