Field control of strawberry fruit rot (Botrytis cinerea Fr.,) by fungicides (II)

Fungicide trials against strawberry fruit rot (Botrytis cinerea Fr.) were conducted in 1968, 1969 and 1970 on cv. Cambridge Favourite. Dichlofluanid was applied at 6 lb a.i./acre/year (6.72 kg/ha), tetrachloroisophthalonitrile at 7.5 lb a.i./acre/ year (8.41 kg/ha) and benomyl at 1.5 lb a.i./acre/year (1.68 kg/ha). The first spray was applied when two or three flowers per plant had opened, and one, two or three subsequent applications were made at approximately 10-day intervals. Three or four applications gave better control than two.

Application of any of the three fungicides reduced fruit rot and resulted in improved yield. Benomyl and tetrachloroisophthalonitrile caused malformation of fewer fruits than dichlofluanid.     

Evaluating weed control and response of newly planted peach trees to herbicides

ABSTRACT

Field experiments were conducted in North Carolina to determine peach response to herbicides. Mesotrione, rimsulfuron, and sulfentrazone did not injure newly planted peach trees. However, halosulfuron at the higher rate caused injury to peach trees, but did not reduce tree cross-sectional area or winter pruning weight. Another field experiment was conducted to determine the effect of herbicide-based programs on weed control. Sulfentrazone alone controlled common lamb’s-quarters and henbit but provided poor control of large crabgrass and yellow foxtail. However, a tank mix of norflurazon or oryzalin with sulfentrazone improved control of these weeds over sulfentrazone alone. Terbacil alone or in tank mix rimsulfuron, and flumioxazin alone gave excellent control of large crabgrass and yellow foxtail.     

48%乐斯本乳油防治桃树蚜虫的效果

１９９９ 年５ 月桃蚜（ Ｍｙｚｕｓ ｐｅｒｓｉｃａｅ Ｓｕｌｚｅｒ） 危害期,用１０００ 倍、１５００ 倍、２０００ 倍４８ ％ 的乐斯本（ 毒死蜱） 稀释液进行防治试验,用２０００ 倍４ ．５ ％ 氯氰菊酯作对照。结果表明,不同稀释倍数的乐斯本对桃蚜的防效均达８０ ％ 以上。     

Effects of combined applications of ammonium thiosulphate and fungicides on fruit load and blossom blight and their phytotoxicity to peach trees

Summary

Timing of bloom sprays of ammonium thiosulphate (ATS) for foliar fertilization and fruit thinning, and of fungicides for disease control, is critical in peach production. Initial observations in commercial orchards indicated that ATS and fungicides, when applied as tank mixes, could cause burn of blossoms and shoots, but not when applied separately. Nine fungicides, alone and in combination with ATS, were evaluated on single tree plots in 1993 and five representative treatments were repeated in 1994 under commercial orchard conditions. Treatments were applied by hand-gun from a 100 litre sprayer in 1993 and by air-blast sprayer in 1994. In 1993, fruit number per tree was affected only by ATS and the numbers of blossom blight cankers per tree only by fungicide, with no interaction between ATS and fungicides. There were however some ATS × fungicide interaction regarding phytotoxicity to blossom and one-year old shoots, but the damage to the latter was slight. In 1994 blossom blight did not occur and there was no evidence of phytotoxicity to shoots or blossoms. Fruit number was not affected by any treatment.     

Response of watersprout growth to fruit load and intensity of dormant pruning in peach tree

Watersprout occurrence and growth were investigated over a two-year period in an early maturing peach cultivar (Alexandra) under different intensities of dormant pruning for fruited and defruited trees. A preliminary study focused on identifying the laws that determine the probability of presence and occurrence of watersprouts in relation to watersprout-bearing shoot (WBS) length. The increase in watersprout probability of presence and occurrence resulting from greater WBS length illustrated the high capacity of peach for sprouting. Watersprout lengths were measured, as well as the lengths of young shoots, one-year-old fruit-bearing shoots (FBSs) and older branches considered as WBS in order to evaluate total shoot growth within the tree. Watersprout number and total length tended to be higher under severe dormant pruning and in fruited trees than under light dormant pruning and in defruited trees. This stimulation of watersprout length appeared to compensate for the concomitant lower total length of young shoots, resulting in a constant overall vegetative growth rate for the whole tree. In the second year of the experiment, watersprouts were either removed by summer pruning or not in order to evaluate watersprout incidence on the rest of the tree. After light and severe watersprout removal (WSR), the annual diametrical growth of FBS tended to be higher and lower, respectively, compared to trees not submitted to summer pruning. Light WSR might favour light interception in the centre of the canopy, thus improving assimilate production and allocation to FBS, whereas severe WSR could prevent carbohydrate export from watersprouts to FBS. Under our conditions, the limit at which WSR intensity became detrimental for FBS diametrical growth appeared to be after approximately 75% of the watersprouts were removed. Severe WSR appeared likely to improve fruit diameter, whereas it had no significant impact on the percentage of soluble solids.     

The effect of preharvest calcium sprays on quality attributes,physicochemical aspects of cell wall components and susceptibility to brown rot of peach fruits (Prunus persica L. cv. Andross)

This study was planned to evaluate the effect of preharvest calcium sprays on physicochemical aspects of cell wall components, activity patterns of pectin-modifying enzymes and susceptibility to brown rot (Monilinia fructicola) of peach fruits (Prunus persica L. cv. ‘Andross’). Six or 10 preharvest calcium sprays were applied with two different formulas (calcium chloride and an ethylenediamine tetraacetic acid (EDTA) chelated calcium form) in equimolar calcium concentration (0.12% Ca, w/v). After harvest, peach fruits were cold stored (0 °C, 95% R.H.) up to 4 weeks. Calcium content increased significantly in the calcium-sprayed peaches both in the peel (25–42%) and in the flesh (11–17%), 1 d after harvest. Calcium chloride sprays were more effective than those of chelated calcium, whereas the increase of calcium content in the fruits seems to be unaffected by the 6 or 10 calcium sprays. The increase of cell wall calcium corresponded to increase of calcium in the insoluble pectin fraction, whereas no differences were detected in the calcium of water-soluble pectin fraction. Ethylene production, respiration rate, uronic acid content and activity of pectin-modifying enzymes did not indicate substantial differentiations by preharvest calcium sprays as ripening progressed after harvest or cold storage. Calcium sprays resulted in significant decrease of brown rot development, although no effect on disease incidence was recorded.     

杧果蒂腐病菌对多菌灵的抗药性测定及其杀菌剂筛选

对来自海南3个地区的86个杧果蒂腐病菌(Botryodiplodia theobromae Pat.)菌株进行了对多菌灵的抗药性测定,结果表明,杧果蒂腐病菌群体中存在着对多菌灵抗性的群体。采用生长速率法进行了23种杀菌剂对4株杧果蒂腐病菌的室内毒力测定,通过EC50值、EC90值及与多菌灵的交互抗性等的综合分析,结果表明,作为防治杧果蒂腐病的首选药剂有咪鲜胺锰盐、丙环唑、氟硅唑、咪鲜胺、异菌脲、苯醚甲环唑、戊唑醇、腈菌唑、吡唑醚菌酯和井冈霉素10种杀菌剂,可选杀菌剂还有百菌清和代森锰锌。杧果蒂腐病菌除对多菌灵产生抗性外,还对甲基硫菌灵、醚菌酯和烯唑醇3种杀菌剂产生了抗药性。通过交互抗性分析,多菌灵、甲基硫菌灵和烯唑醇3种杀菌剂之间存在交互抗性,而醚菌酯与井冈霉素之间存在负交互抗性。为了避免杧果蒂腐病菌对某种杀菌剂产生抗药性,建议上述可选用杀菌剂交替使用。     

苹果轮纹病药剂筛选与药剂配方

为解决苹果枝干轮纹病有效防治药剂缺乏的问题,1998—1999年在富士苹果枝干轮纹病树上开展其病害的药剂配方、浓度、防治次数、时期筛选及病斑不同刮治程度试验,2000—2002年在富士苹果枝干轮纹病树上开展果实轮纹病防治试验,结果表明,5波美度石硫合剂∶硅石粉剂=100∶4或100∶6对苹果枝干轮纹病具有显著的增效作用;1年2次施药效果显著;第1次施药前应采取轻刮,以后防治直接用药;多菌灵与波尔多液交替、多菌灵与石硫合剂∶硅石粉剂交替使用采收期与贮藏期防治果实轮纹病效果均突出;套袋果实轮纹病防效达100%。     

不同杀菌剂对苹果树腐烂病防治效果研究

为了筛选有效防治苹果树腐烂病的杀菌剂,测定了5种化学杀菌剂对苹果树腐烂病菌的室内抑制活性和田间防治效果,并比较了不同"杀菌剂+助剂+刮治"的病疤处理方式在田间的防治效果。室内试验结果表明:5种杀菌剂对苹果树腐烂病菌均具有抑制作用,其中噻霉酮和甲硫·萘乙酸抑菌作用最为显著,抑菌率分别为93.19%和90.07%,丁香菌酯防效最差,抑菌率仅为48.60%;显微观察发现,5种杀菌剂处理能够导致苹果树腐烂病菌菌丝发生不同程度的畸形、顶端膨大和原生质外溢,并且菌丝变形程度随处理时间延长而加重。田间试验结果表明,以"甲硫·萘乙酸+乙基化和甲基化植物油+刮治"的处理方式对苹果树腐烂病菌的防治效果最佳,病疤愈合度大于33%。     

中华寿桃细菌性穿孔病的综合防治技术

阐述了细菌性穿孔病危害中华寿桃的症状、发病条件及侵染循环,提出选地建园条件和通过果实套袋,应用农耕防治和药剂防治相结合的综合防治措施。     

10种杀菌剂防治甜瓜白粉病的效果

白粉病是甜瓜的主要病害,为筛选出安全高效的防治药剂,笔者对立架棚栽甜瓜进行了10种杀菌剂防治白粉病的小区试验。结果表明,62.25%仙生可湿性粉剂500倍液、30%特富灵可湿性粉剂3000倍液和4%朵麦可水剂1500倍液,对甜瓜白粉病的防效分别达88.86%、87.43%和85.30%,且对甜瓜安全无药害,是目前防治甜瓜白粉病较理想的药剂。生产上应抓住白粉病始见期用药,视病情发展每隔7-10d喷药1次;使用剂量:62.25%仙生500倍液,30%特富灵3000倍液,4%朵麦可1500倍液。     

柿顶腐病综合防治技术

柿顶腐病（果农俗称“柿黑屁股病”）是近年发生在广西恭城水柿、华南牛心柿上的一种新病害;该病主要危害果实,可使果实3～5d内快速软化、腐烂,无法加工柿饼和脆柿,许多柿园因此而遭受了严重损失。笔者经过多年研究,初步明确了该病是缺硼为主而引起的生理性病害,     

Field control of strawberry fruit-rot (Botrytis cinerea Fr.) by fungicides

Dichlofluanid effectively controlled strawberry fruit rot (Botrytis cinerea Fr.) in a series of field experiments from 1965 to 1967. Less than 1 % of fruits were infected where 6 lb./acre/year was applied in three sprays (0·1 % a.i. w./w.) at early flower, main flower and late flower stages. Less mildew (Sphaerotheca alchemillae (Grev.) Junnell) developed on fruits of cv. Royal Sovereign after sprays of dichlofluanid than after thiram or difolatan.

Yield of sound fruit was increased by all three fungicides; on cv. Talisman the yield was greatest with dichlofluanid and on cv. Royal Sovereign with thiram. Fruits of Royal Sovereign were damaged by dichlofluanid and to a lesser extent by thiram; the fruits were smaller and more of them were malformed, relative to the unsprayed plants. The fruits of Talisman were undamaged by the standard rates of thiram and dichlofluanid.     

夏季药液刷干技术防控苹果树腐烂病的应用及效果调查

为进一步明确夏季药液刷干技术在我国苹果树腐烂病防治方面的应用范围和效果,我们对陕、甘、豫、晋四省随机选取的110个苹果园按五点取样法进行了调查。结果显示,树龄6～25年的苹果园中,应用该技术的果园占调查果园总数的61.6%;相比未采用该技术的苹果园,发病株率平均降低48.7%。技术应用后,不同树龄苹果园单株新病斑数减少18.5%～50.7%,特别是苹果树主干部位病斑减少30.2%～50.5%。可见,夏季药液刷干技术对于苹果树腐烂病防控具有明显效果。同时应结合监测预警、增强树势、清除病残体等措施,实现该病害的可持续综合防控。     

Conservation of veteran trees within historical gardens (COVE): a case study applied to Platanus orientalis L. in central Italy

Many veteran trees characterize the landscape of Mediterranean historical parks and gardens, representing unique values from ecological, cultural, social and historical points of view. The absence of natural regeneration is one of the main limits for their conservation. The main purpose of this research was to combine theoretical reasoning and practical solutions to maintain this rich tree heritage. A protocol based on an interdisciplinary approach was developed and applied to the plane trees (Platanus spp.) within the formal garden of Villa Lante of Bagnaia (Viterbo, Italy). The COVE analysis consisted of the following four phases: i) selection of veteran tree species after gathering and comparing historical information; ii) taxonomic identification based on morphological and molecular analyses; iii) tree inventory in GIS environment; and iv) vegetative propagation by woody cuttings and micropropagation.The plane trees surveyed grow on three level terraces and significantly differ in size and phytosanitary conditions according to their topographic position. Molecular analyses indicated a genetic uniformity for the plane trees studied and their memberships to P. orientalis species. This evidence suggests that all specimens belong to the original planting dating back to 1576. All individuals showed a high susceptibility to the pathogen Ceratocystis platani even though so far there is no evidence of canker stain attack. Woody cuttings from the most vigorous individual showed 80% rooting rates. In vitro micropropagation using node culture approach provided healthy plants, maintaining the genetic fidelity respect to mother plant after three years of culture. The obtained results represent a successful example of integrated research for germplasm conservation and management of veteran trees within historical villas in Central Italy.     

Growth and yield response of ‘Correll’ peach trees to fumigation with DBCP

A study was conducted to evaluate the effect of the nematicidal soil-fumigant DBCP (1,2-dibromo-3-chloropropane) on a peach (Prunus persica L. Batsch.) orchard planted on a site with high potential for “short life”. ‘Correll’ peach trees on ‘Lovell’ rootstock were planted on a Ruston fine sandy loam soil (Typic Paleudult, fine loamy, siliceous, thermic) on which 2 generations of peach trees had been grown. Increased tree growth and yield occurred when DBCP was applied twice (pre-plant and 1 year post-planting). After 4 years, there were no differences in the nematode populations or foliar nutrient content as a result of fumigation with DBCP.     

Evaluation of the effectiveness of soil-applied plant derivatives of Meliaceae species on nitrogen availability to peach trees

We assessed the effect of soil-applied derivatives of melia (Melia azedarach L.) and neem (Azadirachta indica A. Juss) on nitrogen (N) soil availability, root uptake and peach (Prunus persica L.) growth. First we evaluated the effectiveness of experimentally prepared amendments made with fresh ground melia leaves or commercial neem cake incorporated into the soil as nitrification inhibitors, then we evaluated the effect of fresh ground melia fruits and neem cake on growth and N root uptake of potted peach trees, and on soil microbial respiration. Soil-applied fresh ground melia leaves at 10 and 20 g kg⁻¹ of soil as well as commercial neem cake (10 g kg⁻¹) were ineffective in decreasing the level of mineral N after soil application of urea-N as a source of mineral N, rather they increased soil concentration of nitric N and ammonium N. The incorporation into the soil of fresh ground melia fruits (at 20 and 40 g kg⁻¹) and neem cake (at 10 and 20 g kg⁻¹) increased N concentration in leaves of GF677 peach × almond (Prunus amygdalus) hybrid rootstock alone or grafted with one-year-old variety Rome Star peach trees. An increase in microbial respiration, leaf green color and plant biomass compared to the control trees were also observed. The Meliaceae derivatives did not affect, in the short term (7 days), N root uptake efficiency, as demonstrated by the use of stable isotope ¹⁵N, rather they promoted in the long term an increase of soil N availability, N leaf concentration and plant growth.     

果树钙营养缺乏的补救与防治

植物正常生长需要碳、氢、氧、氮、磷、钾、钙、镁、硫、铁、硼、锰、锌、铜、钼、氯等营养元素,这些元素在植物体内是同等重要的,相辅相成,缺一不可.通常人们把氮、磷、钾称为大量元素,把钙、镁、硫称为中量元素,其他为微量元素.但在水果生产中,有些品种对钙的需求量有时超过钾,由此可见钙在水果生产中的作用非同小可.我们应该加强对钙的研究,注重对缺钙的原因进行探讨,采取积极的补救和防治措施.……     

Root storage of nitrogen applied in autumn and its remobilization to new growth in spring of persimmon trees (Diospyros kaki cv. Fuyu)

This study was conducted to understand the effect of N supply in autumn on its uptake and distribution in tree parts and the utilization of reserve N the following year in persimmon trees (Diospyros kaki cv. Fuyu). The treated trees received 22.5-g N each for two successive years as a 3.5% urea solution from September 18 at 5-day intervals. Trees absorbed about 30% on average of the N applied in autumn. Sixty four to 83% of the N absorbed in autumn was in perennial parts, and 65–72% of that was in roots. Total N in perennial parts of the tree fertilized with N increased by over 4.28 g while leaf N changed little during senescence, indicating that the reserve N was constituted mostly by the N absorbed in autumn. Total N in the new growth was about the same as the amount of N declined in spring from perennial parts, indicating that there was little contribution by soil N to sustain new growth. Total dry weights of new growth the following year in a with-N tree were greater by over 34 g than those in a without-N tree.