Fungicides for the control of Mycogone perniciosa (Magn.), the cause of wet bubble on the cultivated mushroom

Two formulations of chlorothalonil (as Daconil 2787) were compared for their activity against Mycogone perniciosa Magn. on the cultivated mushroom Agaricus bisporus (Lange) Imbach. At the same does rates, the flowable formulation was more toxic than the wettable powder to both pathogen and host, but more marketable mushrooms were obtained from diseased plots treated with the flowable formulation at each dose rate (1.0, 0.5 and 0.1 g ai m^?2). Levels of disease control were related to dose rates, making it impracticable to lessen toxicity to mushrooms by reducing the dose rate. Fluotrimazole was less active than chlorothalonil against M. perniciosa and was more toxic to mushrooms.     

The use of chlorothalonil for the control of benzimidazole tolerant strains of Verticillium fungicola (Preuss) Hassebr. on the cultivated mushroom

Chlorothalonil (as Daconil 2787, 75 % a.i., w.p.), applied as a drench, reduced the incidence on mushrooms of Verticillium fungicola which was tolerant to certain benzimidazole fungicides. Compared with zineb, chlorothalonil gave better disease control, required only one application and did not stain sporophores. Incorporation of chlorothalonil into the casing layer caused toxicity to the crop and depressed the yield. Where tolerance was not a problem, benomyl gave better disease control than chlorothalonil.     

Relation between the initial nitrogen content of mushroom compost and the duration of composting

With a 3-day duration of Stage I of composting, an initial nitrogen (N) content of about 1.4% of the dry matter resulted in a shorter time in Stage II and a 14-day earlier start to cropping than a 2.4% N content. In 6 weeks cropping from each compost, the yields of mushrooms were similar.Following 13 and 23 days in Stage I, initial N content had little or no effect on the duration of Stage II or on the start of cropping, but the yield of mushrooms was greater from composts with the higher N content. These results support the proposition that with increasing duration of composting a higher initial N content of the compost is acceptable, and probably desirable, for preparing a successful compost.A direct relation between duration of composting and losses of water and dry matter from the compost was confirmed.The occurrence of Coprinus spp. (ink caps) fruit bodies during mushroom cropping was not a good indication of subsequent yield of mushrooms.     

The yield gap of mango in Phrao,Thailand, as investigated through comparative performance evaluation

Farmers in Phrao, north Thailand, have often, on a “trial-and-error” basis, planted mango (Mangifera indica L.) in orchards composed of mango, lychee (Litchi chinensis Sonn.) and longan (Dimocarpus longan Loureiro). This met with varying success. In 1993, a comparative performance analysis (CPA) of 45 orchards containing mango was done to identify land and management aspects that condition the level of the mango productivity. The orchards were often situated on podzolic soils on hills, footslopes, and terraces that dry out deeply during the dry season. Yields were expressed in farm-gate prices since middlemen purchased the produce from farmers “on the tree”. With many orchards having “low” yields and 18 having “0” yield, the yield data had a loglinear distribution. Using data from all sites, a final model that estimates Ln(yield+1) was derived; it quantifies contributions to the total yield gap for each identified specific yield constraint. It suggests that yields increased if: (i) it was not an “off” year (caused by the biennial bearing behaviour of mango; use of growth regulators may remedy this); (ii) the orchard was situated on a hill or on soils with a relatively high pH or poor water holding capacity (mostly shallow soils with SCL topsoil; water stress causes crop dormancy and induces flower initiation); (iii) the possibility existed to apply supplemental irrigation water (orchards having a growth flush or in a fruit bearing stage require adequate water management possibly including supplemental irrigation); (iv) in established orchards weeding by tractor was practised (this causes root pruning that affects the trees physiological cycle); (v) pruning was practised (this was normally done to remove branches damaged by stem boring caterpillars, all orchards suffered from this serious problem); (vi) spraying by motor sprayer was done that dispenses pesticides, preferably Azodrin (monocrotophos), deep into the canopy. Based on data covering one production season only, the model suggests that environmental factors (location and pH) account for some 30% of the yield gap defined by the difference of the average production situation with the anticipated best one, that management factors account for 49% and the year effect (species attribute) for 21%. Management of mango orchards requires use of up-to-date technology since responses provide exponential returns. It not only demands that farmers are knowledgeable and experienced but also that a well-informed extension service collaborates closely with researchers.     

Vergleich von Anbausystemen beim Apfel in Abhängigkeit von Sorte und Unterlage: Schlanke Spindel und Güttinger-V-System

To the 11th leaf the influence of two planting systems on yield and fruit size of apple cultivars ‘Golden Delicious, Weinsberg’ and ‘Jonagold, Rubinstar’ grafted on the dwarfed rootstocks M 9 and P 16 was investigated. The planting systems “Slender Spindle” (3.25 × 1.25 m) and “Güttinger-V-System” (3.50 × 0.60 m) were compared. In average of both cultivars and rootstocks the “Güttinger-V-System” let to significantly higher yields than the planting system “Slender Spindle”. The difference between the planting systems amounted to 121.7 t/ha from the 3rd to the 11th leaf. In this period the annual per-hectare yield of the “Güttinger-V-System” was in average 13.5 t higher than the yield of the “Slender Spindle”. The simple fruit weight of the 3rd to the 11th leaf was affected by the planting system. For both rootstocks and cultivars the simple fruit weight of the “Slender Spindle” was significantly higher than that of the “Güttinger-V-System”. However the fruit size sorting showed for both cultivars no mentioning differences between the planting systems. To the additional yield of the “Güttinger-V-System” face additional costs for the installation of the orchard and for the formation of crown. Thus the decision for this planting system will be influenced in a high measure from the producer price.     

Einfluss organischer N-Dünger auf die Ertrags- und Wuchsleistung der Apfelsorte ‘Jonagold’

In the organic production of fruits there are 30% lower yields than in the conventional or integrated production. Changes concerning plant protection, weed control and N-fertilization are discussed to be possible causes. In the presented trials the influence of organic N-fertilizers on growth and yield of the apple-variety ‘Jonagold’ is investigated. The organic fertilizers “Vinasse” (product resulting from the converting of sugar-beet molasses), “Haarmehlpellets” (pellets of grounded pig bristles), “Rizinusschrot” (grist of the seed of Ricinius communis), “Rapsschrot” (coarse colza meal), “Phytopearls” (residue of maize converting), “Maltaflor” (malt germs and “Vinasse”) and manure were proved. Also the mineral N-fertilizers calcium-ammonium-nitrate and compost were used. The tests were made both in an orchard with integrated production (location Osnabrück) and in an orchard with organic production (location Jork). All tested fertilizers had no influence on the growth and yield of the apple variety ‘Jonagold’. The annual N-uptake of apple-trees in their years of highest yield adds up to 90 and 100?kg?N/ha. This consumption was met by the N-supply of the soil (N_min in Feb./March + N-mineralisation) on both locations. To prevent a possible temporary N-deficit in the first half of the vegetation period a fertilization (30?kg?N/ha) is suggested with organic fertilizers, which release a high N-amount at the latest from the second year of utilization.     

不同地区有害疣孢霉菌株对一些杀菌剂的敏感性测定

从上海、浙江、江苏、福建的蘑菇菇房中采集了有害疣孢霉(Mycogone Perniciosa)19株,并从国外收集了7株,其中一株为红丝菌疣孢霉(M.rosea),进行室内杀菌剂敏感性测定,结果表明,江、浙、沪一带分离的有害疣孢霉菌株对苯并咪唑类杀菌剂已产生一定的耐药性,而对施保功仍敏感。其它地区有害疣孢霉菌株对所试杀菌剂均敏感。     

Emergence and seedling growth of pepper as influenced by soil compaction,nutrient status and moisture regime

Studies on the influence of seed-bed condition on the emergence and development of pepper seedlings (Capsicum frutescens L.) revealed that seed-bed compaction delayed and reduced seedling emergence. High nutrient and organic matter content accentuated the severity of soil compaction, regardless of whether the soil moisture was low or high. Influence of compaction was less on “dry” poor soil. Best seedling emergence was obtained from “moist” crumbly “rich” soil. However, “moist” crumbly “poor” soil, moist compacted poor soil, “dry” crumbly rich soil and “dry” crumbly poor soil also gave very high seedling emergence. The dry compacted rich soil gave the poorest cumulative emergence figures. High soil moisture regime and high nutrient content reduced the severity of soil compaction on seedling root and shoot development. Soil compaction also caused abnormal hypocotyl morphology in seedlings that germinated but failed to emerge.     

七种食用菌消毒剂抑制霉菌效果的比较研究

在PDA平板培养基上对7种常见食用菌消毒剂的抑制霉菌效果进行比较研究。结果表明。在同等条件下甲醛对霉菌抑制效果最好，多菌灵效果次之，之后是克霉灵。百菌清、甲基托市津、甲霜灵、代森锰锌均不太适宜在平菇生产中当作防霉剂使用。     

N-Freisetzung von organischen N-Düngern unter überdachten Bracheparzellen

In a two years lasting trial the N-release of organic N-fertilizers should be analysed under covered fallow plots during the vegetation period. The following fertilizers were proved: cattle manure from two locations, “Vinasse” (product resulting from the converting of sugar-beet molasses), “Haarmehlpellets” (pellets of grounded pig bristles), “Rizinusschrot” (grist of the seed of Ricinius communis), “Rapsschrot” (coarse colza meal), “Phytopearls” (residue of maize converting), “Maltaflor” (malt germs and “Vinasse”), “Agrobiosol” (biomass from Penicillium) and “Horndünger” (horn parings in different fractions). In comparison with these organic fertilizers the mineral N-fertilizer calcium-ammonium-nitrate was used. With the exception of the control all variants got an annual N-fertilization of 90?kg?N/ha. The N-mineralisation of the soil caused by the organic substance, which was in the soil before the trial started, amounted to 84?kg?N/ha in the first and to 59?kg?N/ha in the second year of experience. In both years the N-mineralisation was higher in the second half of the vegetation period (July–November) than in the first half (March–July). In the first year the amount of N-release was clearly less than the given quantity of the N-fertilizer with the exception of “Agrobiosol”. Especially the two manure-variants showed N-immobilisation. “Agrobiosol” showed the highest N-release of the tested organic N-fertilizers. In the second year the N-release both of the two manure-variants and of “Rapsschrot”, “Phytoperls”, “Maltaflor”, “Agrobiosol” and “Horndünger” increased clearly. It was between 51 and 101% of the N-quantity given in the second year. N-release was particularly high by “Agrobiosol”, “Horndünger” and “Rapsschrot”. This increase could be traced to the mineralisation of the remained organic substance given in the first year. The variants “Haarmehlpellets” and “Rizinusschrot” had the same N-release as in the first year. The application of “Vinasse” showed a clear decrease. When “Rapsschrot”, “Phytoperls”, “Maltaflor”, “Agrobiosol”, “Horndünger” or manure are given for many years, one can consequently count on an increase of the annual N-mineralisation. Considering the results of both years of the trial the organic fertilizers “Agrobiosol”, “Horndünger” and “Maltaflor” can be classified as quickly effectiveN-fertilizers, “Haarmehlpellets”, “Rizinusschrot” and “Phytopearls” as moderately effective and “Rapsschrot” and “Vinasse” as slowly effective ones.     

Guazatine control of sour rot in lemons,oranges and tangors under various storage conditions

Guazatine (1-17-diguanidino-9-aza-heptadecane acetate) was compared with sodium orthophenylphenate (SOPP), sec-butylamine (2-AB), benomyl and tridemorph for the control of citrus sour rot (Geotrichum candidum) under local marketing, export, and ethylene (C₂H₄) degreening storage conditions. Guazatine at 25–125 mg/l gave better control than 20 g/l SOPP, 10 g/l 2-AB and 250 mg/l benomyl in artificially inoculated ‘Eureka’ lemons stored at 27° C and high humidity for 6 days. At 500 mg/l, guazatine gave better control than 20 g/l SOPP, 10 g/l 2-AB or 500 mg/l benomyl in dip-inoculated ‘Eureka’ lemons, treated and packaged as for export and stored at 7° C for 2 or 10 weeks. At 250 mg/l, guazatine provided better control than 20 g/l SOPP, 5 g/l 2-AB, 250 mg/l benomyl or 1000 mg/l tridemorph in artificially inoculated ‘Washington’ navel oranges held for 4 days under degreening-conditions of 27° C and 90% RH with added C₂H₄.     

Factors Controlling Flowering in Seed-Raised Freesia Plants

The effect of plant age, temperature and day-length on flower initiation and development in “ K. & M. Super ” freesias has been studied.

The flowering response decreased with increasing temperature and the critical temperature for flower initiation was found to be about 21°C. An interaction of plant age, temperature, and duration of treatment was present. Short days (9 hrs.) slightly stimulated flower initiation in“ Yellow K. & M. Super” but delayed it in “ Blue K. & M. Super” freesias. Short-day treatment in the open during the summer had no significant effect, whereas shading markedly hastened flowering.

Flowering could be initiated at an early stage, but older plants were more responsive, especially those of “Blue K. & M. Super”. Optimum temperatures for flower initiation were 12-15°C., applied for 6-9 weeks after the plants had formed about seven visible leaves.

Abnormal inflorescences in freesias, recognized by enlarged bracts and irregular spacing of the florets (so-called “gladiolus-like flowers”), appeared to result from incomplete flower initiation. In extreme cases flower stalks without any flowers were formed. In order to avoid such abnormal flowering it was important that the first floret in the inflorescence should have reached a certain stage (P₂) of development before low-temperature treatment was discontinued.     

Vergleich von Anbausystemen bei der Birne in Abhängigkeit von Sorte und Unterlage: Schlanke Spindel und Güttinger-V-System

To the tenth leaf the influence of two planting systems on yield and fruit size of pear cultivars ‘Conference, 202’ and ‘Alexander Lucas’ grafted on the rootstocks Quince A (MA) and Quince C (MC) was investigated. The planting systems “Slender Spindle” (3.25?×?1.25 m) and “Güttinger-V-System” (3.50?×?0.60 m) were compared. The “Güttinger-V-System” led to higher yields than the planting system “Slender Spindle”. In average of both cultivars and rootstocks the difference between the planting systems amounted to 75.9 t/ha from the third to the tenth leaf. To the additional yield of the “Güttinger-V-System” face additional costs for the installation of the orchard and for the formation of crown. Thus the decision for this planting system will be influenced in a high measure from the producer price.     

“互联网+”助力食用菌产业升级

食用菌不仅味道鲜美、营养价值也很丰富,越来越受到人们的喜欢。食用菌产业近年来不断扩大以此来满足人们的需求,其前景是非常可观的。尤其是近年来科技的不断创新,互联网的大面积普及,形成了新的产业模式,"互联网+"有着开放性、共享性、去中心化的特征,食用菌产业由"互联网+"带动,利用互联网集成大数据的特点,能够很好地带动食用菌转向产业化。     

Eradicant action of fungicides applied to dormant peach trees for control of brown rot (Monilinia fructicola)

There is evidence to suggest that the eradication of Monilinia fructicola in infected peach peduncles in winter may reduce brown rot during the subsequent season. In a series of experiments, in which treatments were applied in the field and the results assessed in the laboratory, benomyl and arsenic or mercury compounds were more effective in suppressing sporulation from overwintering infections than any of the other materials tested. Benomyl effectively suppressed sporulation from infected peach peduncles and mummified peach fruits and was not phytotoxic. Sodium arsenite was an effective eradicant of M. fructicola in peach peduncles and mummified peach fruit at 0·1% and 0·3%, but it was phytotoxic to both peach and apricot trees at rates as low as 0·01% whether applied in mid-winter or at early bud-swell. Phenylmercury chloride (PMC), mercury acetimide at 0·06% Hg and phenylmercury dimethyldithiocarbamate at 0·015% Hg were effective eradicants. At lower rates the mercurials were unsatisfactory. No phytotoxicity was observed following dormant applications of the mercury compounds.

Lime-sulphur plus oil was the best of the remaining materials. DNOC performed about as well as lime-sulphur on peduncles but failed to suppress sporulation on mummified fruits and was occasionally phytotoxic.

Sodium pentachlorophenate was superior to pentachlorophenyl acetate at the same rate, and, in contrast with some overseas experience with peaches and apricots, was not phytotoxic in these tests.

Bordeaux mixture, fentin acetate, N.C.I584, captan, captafol and dichlone, although not phytotoxic, did not show significant eradicant or antisporulant action.

There was some evidence that PMC acted both as an eradicant and an antisporulant.     

Fast germination of parsley seeds

The time from sowing to 50% radicle protrusion of parsley seeds (Petroselinum crispum L.) was about 1 month at 5°C and about 1 week at 15°C. Osmotic pre-treatment (“priming”) with a polyethylene glycol “6000” solution of ?12 bars water potential (302 g PEG “6000” per 1 kg distilled water) at 15°C for 3 weeks under aerobic conditions reduced this median radicle protrusion time at 15°C to 1 or 2 days for seeds which had been surface-dried after treatment, 2 or 3 days when they had been air-dried and stored for 1 week, and 3 or 4 days after 10 weeks' dry storage. The uniformity in germination time of an untreated seed population was usually good, and care was needed not to make this worse by “over-priming”. An appropriate pre-treatment could, however, slightly improve the uniformity. Germination percentage remained unaffected but the pre-treatment could appreciably improve the emergence percentage of seeds sown in wet soil. In a small-scale experiment out of doors, the weight of plants from certain seed treatments was significantly greater after 14 weeks' growth than that from untreated seeds.     

Phytotoxic properties of Drosophyllum lusitanicum leaf extracts and its main compound plumbagin

The aim of this work was to evaluate the phytotoxic properties of aqueous and hexane extracts from the insectivorous plant Drosophyllum lusitanicum (L.) Link using lettuce and bread wheat as model species. The results obtained confirmed that both germination and seedling growth bioassays were sensitive and able to detect the heterotoxicity potential of D. lusitanicum extracts. Aqueous and hexane extracts at several concentrations significantly inhibited the seed germination of lettuce and wheat, although wheat was less sensitive. The inhibitory effects of plumbagin, the major compound found in D. lusitanicum hexane extracts, were also evaluated. Comparing the results of the assays obtained with extracts and plumbagin it was postulated that plumbagin is the principal compound responsible for the phytotoxic effects of the extracts on lettuce but not on wheat. Therefore, although the phytotoxic potential of D. lusitanicum was demonstrated, further studies are needed to clearly specify the compounds responsible for the inhibitory effects and to ensure if the results obtained with the model species are reproducible to weed species in field conditions.     

Accumulation of phytotoxic organic acids in reused nutrient solution during hydroponic cultivation of lettuce (Lactuca sativa L.)

Proper nutrient solution management in the root zone is the first consideration for the adoption of a closed hydroponic system. Plant roots often exude numerous organic acids, which are known to inhibit growth. To investigate the accumulation of these phytotoxic organic acids as root exudates, lettuce (Lactuca sativa L.) was hydroponically grown in reused nutrient solution. Organic acids were extracted with diethyl ether from the reused nutrient solutions (RNS), root residues, and activated charcoal (AC) then quantified by GC/MS. Five individual organic acids were identified from the root residues and seven from the reused nutrient solutions. After 90 days of lettuce cultivation, in the treated AC in 3RNS, benzoic, phenylacetic, cinnamic, p-hydroxybenzoic, lauric, phthalic, vanillic, palmitic, and stearic acids were identified. In contrast, little or no organic acids were detected in the 3RNS treated with AC (3RNS/AC). Artificially applied pure organic acids ranging from 25 to 200 μM inhibited lettuce growth in a concentration-dependent manner. Lettuce growth was also greatly reduced in the nutrient solutions containing a externally applied, simulated mixture of the organic acids as in the 3RNS. Lettuce growth was not inhibited following the addition of AC (2.5 g/L) to the nutrient solution containing the mixture of organic acids. Our results demonstrated that organic acids were accumulated in reused nutrient solutions and were phytotoxic to lettuce growth. Also, this study showed that the addition of AC reduces the phytotoxic effects by eliminating the organic acids.     

Effect of Time of Application of Fertilizer Nitrogen on the Growth,Flower Development and Fruit Set of Maiden Apple Trees,Var. Lord Lambourne,and on the Distribution of Total Nitrogen Within the Trees

Fertilizer nitrogen was applied to pot-grown trees during the year of initial scion growth either as “spring N”, “summer N” or “autumn N”, while other trees were left untreated—“minus N”. Tree performance was followed until fruit set the following summer.

At regular intervals whole trees were sampled, divided into as many as seven different parts, which were separately weighed, dried and analysed for total nitrogen. Specimens were also taken for histological examination of flower bud development.

The large amount of fertilizer given as “spring N” resulted in extensive root damage from which the trees did not recover fully; nevertheless they produced large, vigorous scions. After “spring N” and “summer N” at lower dosages the total N content of all parts increased substantially and rapidly. “Autumn N” was absorbed more slowly and remained largely in the roots during the winter, when a considerable amount of root growth took place.

Flowers were initiated in late July or early August on all trees except those given “spring N”, on which flower primordia were not initiated until September. The development of flower buds was accelerated during September on “summer N” trees compared with those left untreated. From the end of November until the end of March no further differentiation took place on “minus N” or “spring N” trees, but it continued on the other treatments, especially following “autumn N”.

“Summer N” and “autumn N” trees were 4–5 days in advance of the others in flowering. “Summer N” trees had large flowers and large green primary leaves, whereas those on “autumn N” trees were smaller and the leaves were initially pale, though turning dark green during blossoming.

When the blossoms were self-pollinated under controlled conditions virtually no fruit was set on “minus N” and “spring N” trees, but “summer N” gave an appreciable set and “autumn N” a heavy set. Only the “summer N” and ”autumn N” flowers had ovules that remained viable six days after anthesis, which was the minimum period found necessary for the pollen tubes to effect fertilization.

It is suggested that fertilizer nitrogen stimulates the synthesis of a kinin-like factor in the roots and that the difference in response to applications at different times of year depends upon the stage of development of the flower buds when this factor reaches them.     

Post harvest treatments to control eggplant deterioration during storage

Eggplant (Solatium melongena L.) fruits deteriorate rapidly during prolonged storage, mainly due to accelerated senescence of the calyx. Dipping the calyx in a solution containing 200 ppm NAA and 900 ppm prochloraz (active ingredient) retarded calyx senescence and controlled decay. At the end of the growing season in Israel (March-May), dipping the whole fruit in the above solution gave better results than dipping the calyx only. After 14 d of storage at 12°C and 3 d at 20°C, the calyx appeared fresh and green and the fruit was firm. Decay incidence did not exceed 5%. The residual level of prochloraz in fruits that were wholly dipped was less than 0.34 mg 1“'.