scholarly journals Reaction of families and lines of melon to powdery mildew

2011 ◽  
Vol 29 (3) ◽  
pp. 382-386 ◽  
Author(s):  
Rui Sales Júnior ◽  
Glauber HS Nunes ◽  
Sami J Michereff ◽  
Elaíne WL Pereira ◽  
Izabel M Guimarães
Keyword(s):  
Powdery Mildew ◽  
Genetic Variability ◽  
Podosphaera Xanthii ◽  
Severity Scale ◽  
Simple Lattice ◽  
Randomized Design ◽  
Race 1 ◽  
Completely Randomized Design ◽  
Brazilian Northeast ◽  
Important Disease

Powdery mildew, caused by Podosphaera xanthii, is an important disease of melon in the Brazilian Northeast. The objective of this work was to evaluate the reaction of families, lines and cultivars of melon to P. xanthii. Two experiments in simple lattice were carried out under field conditions in the municipalities of Mossoró and Baraúna to evaluate 144 families. In a greenhouse, an experiment was carried out in a completely randomized design to evaluate 19 lines and the cultivars Yellow Queen, Chilton and Hy Mark. Disease was assessed by a severity scale. There was genetic variability among families. The families 4, 5, 11, 14, 18, 23, 33, 42, 101, 112 and 140 were identified in both sites as resistant. The lines LOF-027, LOF-105, LPS-124, MEL-008 and cultivar Chilton showed resistance to race 1 of the fungus.

scholarly journals EMISSÃO DE ÓXIDO NITROSO ASSOCIADO AO USO DE UREIA NO CULTIVO DE MELÃO AMARELO

Nativa ◽  
2018 ◽  
Vol 6 (6) ◽  
pp. 600
Author(s):  
Vanessa Cláudia Vasconcelos Segundo ◽  
Renato Innecco ◽  
Ebenézer De Oliveira Silva
Keyword(s):  
Leaf Area ◽  
Aerial Part ◽  
Dry Mass ◽  
Nitrogen Fertilizers ◽  
Root Part ◽  
Randomized Design ◽  
Number Of Leaves ◽  
Completely Randomized Design ◽  
Brazilian Northeast ◽  
Total Soil Nitrogen

O meloeiro tem grande importância econômica para o Nordeste brasileiro. Entretanto, em seu cultivo utiliza-se insumos que podem prejudicar o ambiente; como, os fertilizantes nitrogenados. Objetivou-se avaliar a emissão de N2O em cultivo de meloeiro amarelo ‘Goldex’. O experimento foi instalado em delineamento inteiramente casualizado, com cinco repetições. Os tratamentos foram: 0 (controle), 1,0; 1,5 e 2 vezes a quantidade de nitrogênio recomendada para cada estádio. Foi analisado o fluxo de N2O, área foliar, número de folhas, massa seca da parte aérea, massa seca dos frutos, massa seca da parte radicular, nitrogênio total do solo, das plantas e N (NH4+ e NO3-) do solo. O fluxo de N2O teve comportamento temporal irregular durante a fase de plântulas e crescente na floração. Os tratamentos afetaram significativamente a área foliar, número de folhas, massa seca da parte aérea, massa seca da parte radicular, nitrogênio da parte aérea e parte radicular das plantas e do solo. A aplicação de nitrogênio, em dosagens superiores à recomendada, não aumentou a produção do meloeiro. E o cálculo do fator de emissão mostrou que a emissão do N2O não atingiu valores prejudiciais ao ambiente.Palavras-chave: fator de emissão, efeito estufa e nitrogênio. NITROUS OXIDE EMISSION ASSOCIATED WITH UREA USE THE YELLOW MELON CROP ABSTRACT: The melon has great economic importance for the Brazilian Northeast. However, in its cultivation uses inputs that can harm the environment; Such as nitrogen fertilizers. The objective of this study was to evaluate the emission of N2O in yellow 'Goldex' cultivar. The experiment was installed in a completely randomized design with five replications. The treatments were: 0 (control), 1.0; 1.5 and 2 times the amount of nitrogen recommended for each stage. N2O flux, leaf area, leaf number, shoot dry mass, fruit dry mass, dry mass of the root portion, total soil nitrogen, of the plants and N (NH4 + and NO3 -) of the soil were analyzed. The flow of N2O had irregular temporal behavior during the seedling phase and increased in flowering. The treatments affected significantly the leaf area, number of leaves, dry mass of the aerial part, dry mass of the root part, nitrogen of the aerial part and root part of the plants and the soil. The application of nitrogen, in dosages higher than the recommended one, did not increase the production of the melon. And the calculation of the emission factor showed that the emission of N2O did not reach values harmful to the environment.Keywords: emission fator, greenhouse and nitrogen.

scholarly journals Tingkat Ketahanan 70 aksesi Plasma Nutfah Kenaf terhadap Fusarium oxysporum Schletch; Assessment of Kenaf Germplasm Against Fusarium oxysporum Schletch

2017 ◽  
Vol 8 (2) ◽  
pp. 65
Author(s):  
Supriyono Supriyono ◽  
Titiek Yulianti
Keyword(s):  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Spore Suspension ◽  
Randomized Design ◽  
Resistant Accession ◽  
New Varieties ◽  
Completely Randomized Design ◽  
Screen House ◽  
Important Disease ◽  
Research Institute

<p>Salah satu penyakit penting yang sangat merugikan tanaman kenaf adalah penyakit layu Fusarium yang disebabkan oleh <em>Fusarium oxysporum</em> Schlecht. Tujuan penelitian ini adalah untuk mengevaluasi tingkat ketahanan aksesi kenaf terhadap jamur <em>Fusarium oxysporum</em>. Penelitian dilakukan di laboratorium dan rumah kasa Balai Penelitian Tanaman Pemanis dan Serat, Malang menggunakan rancangan acak lengkap) yang diulang tiga kali. Dalam evaluasi ini digunakan 70 aksesi dan 1 aksesi tahan (BG-52-135) yang digunakan sebagai kontrol. Inokulasi dilakukan pada 7 hari setelah tanam (HST) menggunakan suspensi spora dengan kerapatan10<sup>5</sup>/ml sebanyak 100 ml setiap bak. Pengamatan intensitas serangan dilakukan mulai 10–40 hari setelah inokulasi (HSI) dengan interval pengamatan lima hari. Pengamatan persentase diskolorisasi batang dilakukan sekali pada 50 HSI. Hasil pengujian memperoleh 1 aksesi (FJ/017) sangat tahan dengan intensitas serangan terrendah (0,83%) dan 14 aksesi tahan dengan intensitas serangan <span style="text-decoration: underline;">&lt;</span>10%, 28 aksesi dengan ketahanan moderat, dan 27 aksesi yang rentan terhadap infeksi <em>F. oxysporum</em>. Aksesisi FJ/017 (aksesi yang sangat tahan) dan 14 aksesi yang tahan: 1064(SUC/012), 1061(SRB/082), 1035(FJ/005), 839(PARC/2709), 955(FJ/003), 842(PARC/2712), 1095(SUC/003), 838(PARC/2708), 957(FJ/ 007), 1065(SUC/023), 1042(CHN/056), 145(BL/118), 1036(FJ/006), dan 778(PARC/2466) dapat digunakan sebagai sumber ketahanan pada perakitan varietas baru.</p><p> </p><p>One of the important disease that very detrimental to kenaf is Fusarium wilt caused by <em>Fusarium oxysporum</em> Schlecht. The purpose of this study was to evaluate the response of 70 kenaf germplasm<span style="text-decoration: line-through;">s</span> accessions against <em>F</em><em>.</em><em> oxysporum</em>. The study was conducted at the Phytopatology Laboratory and screen house of Indonesian Sweetener and Fiber Crops Research Institute, Malang using completely randomized design with three replicates.  Seventy accessions and one resistant accession as control (1267 (BG-52-135) were used in this study.  Inoculation of <em>Fusarium</em> was done 7 days after sowing (das) by sprinkling 100 ml of spore suspension into the soil.  Observation of disease intensity started at 10–40 days after inoculation (dai) and repeated every five days.  Percentage of stalk discolorization was estimated at 50 dai.  The results showed that accession 1040 (FJ/017) had the lowest disease intensity (0.83%), hence was categorized as a highly resitant accession. Fourteen accessions were categorized as resistant with disease intensity below or equal to 10%; 28 accessions were moderate resistant; and 27 accessions were susceptible.  FJ/017 (the highset resistant accession) and 14 resis-tant accessions (1064(SUC/012), 1061(SRB/082), 1035(FJ/005), 839(PARC/2709), 955(FJ/003), 842(PARC/ 2712), 1095(SUC/003), 838PARC/2708), 957(FJ/007), 1065(SUC/023), 1042(CHN/056), 145(BL/118), 1036 (FJ/006), dan 778(PARC/2466)) could be used as resistant  genetic sources  in developing new varieties.</p>

scholarly journals FIELD EVIDENCE FOR A NEW RACE OF POWDERY MILDEW ON MELON

HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 888a-888 ◽  
Author(s):  
James D. McCreight ◽  
Michael D. Coffey ◽  
Thomas A. Turini ◽  
Michael E. Matheron
Keyword(s):  
Powdery Mildew ◽  
Powdery Mildew Resistance ◽  
Genetic Resistance ◽  
Podosphaera Xanthii ◽  
Sphaerotheca Fuliginea ◽  
Imperial Valley ◽  
Field Evidence ◽  
Race 1 ◽  
New Race ◽  
The U.S

Races 1 and 2 of Podosphaera xanthii (syn. Sphaerotheca fuliginea) were defined in Imperial Valley, Calif. 1938 when P. xanthii overcame genetic resistance in `PMR 45'. Race 3 was first observed in the U.S. in 1976 in Texas; 15 additional races of P. xanthii have been reported in the literature since 1996. Races 1 and 2 have been common in Arizona and California based upon the effectiveness of the powdery mildew resistance genes in commercially available melon cultivars grown in these states. Field data from 11 commonly used melon P. xanthii race differentials in 2001 and 2002 indicated the presence of race 1 in the Imperial Valley and San Joaquin Valley of California, and Yuma, Arizona. In spring 2003, the powdery mildew race situation changed. The first evidence was the occurrence of a severe and widespread infection of powdery mildew in a commercial cantaloupe field. The 11 powdery mildew race differentials were susceptible to powdery mildew in a nearby replicated field test. PI 313970, a melon from India, was resistant to this apparent new race of powdery mildew.

scholarly journals Yields Losses Caused by Basal Plate Rot (Fusarium oxysporum f.sp. cepae) in Some Shallot Varieties

2020 ◽  
Vol 35 (2) ◽  
pp. 250
Author(s):  
Hadiwiyono Hadiwiyono ◽  
Kumala Sari ◽  
Susilo Hambeg Poromarto
Keyword(s):  
Correlation Analysis ◽  
Fusarium Oxysporum ◽  
Disease Severity ◽  
Basal Plate ◽  
Yield Losses ◽  
Crop Losses ◽  
Independent Variables ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Important Disease

Basal plate rot or moler caused by <em>Fusarium oxysporum</em> f. sp. <em>cepae</em> (FOCe) is the most important disease of shallot. However, the information of crop losses attributed to the pathogen is still limited, especially related to resistance of shallot. This paper discusses the correlation between disease severity and resistance of some shallot varieties to yield losses. The experiment was arranged by Completely Randomized Design (CRD) with six varieties of shallot as treatments, each of which consisted of 20 shallots, with three times of replications. The independent variables were the disease severity of twisting leaf and rotting of shallot bulb. The association of disease severity versus yield losses in different varieties was based on the correlation analysis. The results showed that both variables were positively correlated to yield losses, which were significantly affected by the level of resistance. Yield losses in resistant and moderate varieties were at the ranges of 2.13-4.38 and 15, 27.26-40.04, respectively.

scholarly journals TOXICITY OF INSECTICIDES USED IN MUSKMELON ON FIRST-INSTAR LARVAE OF Chrysoperla genanigra FREITAS (NEUROPTERA: CHRYSOPIDAE)

2017 ◽  
Vol 30 (3) ◽  
pp. 662-669 ◽  
Author(s):  
BÁRBARA KARINE DE ALBUQUERQUE SILVA ◽  
MAURÍCIO SEKIGUCHI DE GODOY ◽  
ALRICÉLIA GOMES DE LIMA ◽  
ANNA KÉZIA SOARES DE OLIVEIRA ◽  
PATRIK LUIZ PASTORI
Keyword(s):  
Sublethal Effects ◽  
Insect Pests ◽  
Mass Rearing ◽  
First Instar ◽  
Randomized Design ◽  
Lambda Cyhalothrin ◽  
Class 1 ◽  
Completely Randomized Design ◽  
Brazilian Northeast ◽  
Cucumis Melo L

ABSTRACT Brazil is one of the world's largest producers of melon (Cucumis melo L.), and Rio Grande do Norte and Ceará are the largest producers states of the country (99% of exports). This crop had great socio- economic importance in the Brazilian Northeast, however, it is affected by insect pests and consequently, large amounts of pesticides are applied to it, which greatly affect beneficial organisms, such as Chrysopidae. This bioassay evaluated the toxicity of nine insecticides used in commercial crops of muskmelon, applied to first- instar larvae of Chrysoperla genanigra of up to 24-hour-old, from mass rearing cultures. Sublethal effects were evaluated, classifying the insecticides into the toxicity classes recommended by the IOBC. A completely randomized design was used, consisting of ten treatments (clothianidin, pymetrozine, lambda-cyhalothrin, chlorantraniliprole, indoxacarb, pyriproxyfen, beta-cyfluthrin+imidacloprid, imidacloprid, beta-cypermethrin and a control consisted of distilled water). The treatments consisted of exposure of thirty larvae to dry residues of each product in Petri dishes, assessing their mortality, duration of instars, sex ratio, fecundity and viability of eggs from adults of the insects evaluated. The products were classified in toxicity classes as harmful (Class 4) (clothianidin, pymetrozine, indoxacarb, lambda-cyhalothrin, beta-cyfluthrin+imidacloprid, imidacloprid, beta- cypermethrin and pyriproxyfen) and innocuous (Class 1) (chlorantraniliprole) to first -instar larvae of C. genanigra, by calculate their total effect. Based on this work, chlorantraniliprole is the only recommended insecticide for use in integrated pest management (IPM) programs in muskmelon crops.

scholarly journals First report of powdery mildew caused by Podosphaera xanthii race 1 on watermelon in China

2021 ◽  
Author(s):  
Haonan Cui ◽  
Zicheng Zhu ◽  
Zhuo Ding ◽  
Yuanzuo Lv ◽  
Lei Sun ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Podosphaera Xanthii ◽  
First Report ◽  
Race 1

scholarly journals INDUKSI DAN REGENERASI KALUS KELADI TIKUS (Typonium flagelliforme. Lodd. ) SECARA IN VITRO

2020 ◽  
Vol 13 (4) ◽  
pp. 142 ◽  
Author(s):  
SITTI FATIMAH SYAHID ◽  
NATALINI NOVA KRISTINA
Keyword(s):  
Tissue Culture ◽  
Genetic Variation ◽  
Carbon Source ◽  
Genetic Variability ◽  
In Vitro Culture ◽  
Basic Medium ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Group B

<p>ABSTRAK<br />Keladi tikus umumnya diperbanyak secara vegetatif sehingga ragam<br />genetiknya sempit. Penelitian peningkatan keragaman genetik pada keladi<br />tikus melalui kultur in vitro telah dilakukan di Laboratorium Kultur<br />Jaringan, Balai Penelitian Tanaman Obat dan Aromatik (Balittro) Bogor<br />pada bulan April sampai Desember 2005. Bahan tanaman yang digunakan<br />adalah daun steril keladi tikus in vitro. Media dasar yang digunakan adalah<br />Murashige and Skoog (MS) yang diperkaya vitamin dari group B. Sebagai<br />sumber energi digunakan sukrosa sebanyak 30 g/l. Penelitian terdiri dari<br />dua tahap yaitu induksi dan regenerasi kalus. Perlakuan yang diuji pada<br />tahap I adalah beberapa taraf konsentrasi auksin (2,4-D) secara tunggal<br />maupun kombinasi dengan sitokinin (kinetin) terhadap induksi kalus yaitu<br />: 2,4-D 0,1 mg/l; 2,4-D 0,5 mg/l; 2,4-D 1,0 mg/l; 2,4-D 0,1 + kinetin 0,1<br />mg/l; 2,4-D 0,5 mg/l + kinetin 0,1 mg/l; 2,4-D 1.0 mg/l + kinetin 0,1 mg/l;<br />2,4-D 0,1 mg/l + kinetin 0,3 mg/l; 2,4-D 0,5 mg/l +kinetin 0,3 mg/l dan<br />2,4-D 1,0 mg/l + kinetin 0,3 mg/l. Tahap II adalah beberapa taraf<br />konsentrasi benzyl adenin untuk regenerasi kalus. Penelitian disusun<br />menggunakan rancangan acak lengkap dengan pola faktorial dan lima<br />ulangan, dan setiap ulangan terdiri dari satu eksplan. Faktor pertama<br />adalah asal kalus dan faktor kedua adalah beberapa taraf konsentrasi BA<br />yaitu : BA 0,1 mg/l ; BA 0,3 mg/l dan BA 0,5 mg/l. Parameter yang<br />diamati adalah waktu inisiasi kalus, struktur dan warna kalus, jumlah<br />tunas serta penampilan kultur secara visual. Hasil penelitian menunjukkan<br />bahwa kalus asal eksplan daun dapat diinduksi pada perlakuan 2,4-D 1,0<br />mg/l + kinetin 0,1 mg/l dan 2,4-D 1,0 mg/l + kinetin 0,3 mg/l dengan<br />waktu inisiasi 8 sampai 10 minggu setelah perlakuan. Regenerasi kalus<br />terbaik diperoleh pada medium 2,4-D 1,0 mg/l + kinetin 0,3 mg/l<br />mengandung BA 0,3 mg/l dengan rata-rata tunas dan daun yang dihasilkan<br />sebanyak 13,2 tunas dan 4,4 daun.<br />Kata kunci : Keladi tikus, Typonium flagelliforme Lodd., induksi,<br />regenerasi kalus, in vitro</p><p><br />ABSTRACT<br />Induction and regeneration of Rodent tuber calli through<br />in vitro culture<br />Rodent tuber plant (Typonium flagelliforme Lodd) is commonly<br />propagated vegetatively, the repro its genetic variation is narrow. A<br />research to increase the genetic variability of the plant was conducted in<br />Tissue Culture Laboratory of the Indonesian Medicinal and Aromatic<br />Research Institute, Bogor from April to December 2005. The leaf of<br />Rodent tuber in vitro used as an explants. Murashige and Skoog (MS)<br />medium used as basic medium, supplemented with vitamin from B group,<br />sucrose 30 g/l was added into the medium as carbon source. The research<br />consist of two steps : 1) calli induction and 2) calli regeneration. The<br />treatment tested in first step : 2.4-D 0.1 mg/l; 2.4-D 0.5 mg/l; 2.4-D 1,0<br />mg/l; 2.4-D 0.1 + kinetin 0.1 mg/l; 2.4-D 0.5 mg/l + kinetin 0.1 mg/l; 2.4-<br />D 1.0 mg/l + kinetin 0,1 mg/l; 2.4-D 0.1 mg/l + kinetin 0.3 mg/l; 2.4-D 0.5<br />mg/l + kinetin 0.3 mg/l and 2.4-D 1.0 mg/l + kinetin 0.3 mg/l. In the<br />second steps, several concentration of BA were tested i.e: BA 0,1 mg/l ;<br />BA 0,3 mg/l and BA 0,5 mg/l. The experiment was arranged in<br />completely randomized design with factorial pattern. Each treatment<br />consist of five replications. The parameters observed were time of calli<br />initiation, texture, colour of calli and number of shoot and leaves in<br />regeneration. The result showed that calli can be induced on 2.4-D 1.0<br />mg/l + kinetin 0.1 mg/l and 2.4-D 1.0 mg/l + kinetin 0.3 mg/l, eight to ten<br />weeks after culture. The best medium for shoots regeneration contains 2.4-<br />D 1.0 mg/l + kinetin 0.3 mg/l with 0.3 mg/l BA, with mean result of 13.2<br />shoots and 4.4 leaves.<br />Key words : Rodent tuber, Typonium flagelliforme Lodd. bl , induction,<br />regeneration, calli, in vitro</p>

scholarly journals Evaluación de la resistencia a la mustia hilachosa (Thanatephorus cucumeris (Frank), Donk). en líneas y variedades de frijol. Caisán. Panamá, 1997.

2006 ◽  
Vol 10 (2) ◽  
pp. 51
Author(s):  
Emigdio Rodríguez ◽  
Francisco González
Keyword(s):  
Common Bean ◽  
Thanatephorus Cucumeris ◽  
Lattice Design ◽  
Simple Lattice ◽  
Randomized Design ◽  
Susceptible Control ◽  
Hyper Sensitivity ◽  
Completely Randomized Design ◽  
Web Blight ◽  
The Web

This study was carried out with the purpose of identifying genotypes of common bean, with a greater level of resistance to the web blight, in Caisán, Panama. 4335 lines and varieties of common bean were evaluated from seven experiments. A completely randomized design and a simple lattice design were utilized according to the experiments. Experiment repetitions varied from one, two or three depending on the amount of seed available. 62 materials showed an inferior reaction to the web blight in relation to that of the resistant Talamanca control (5 grade). The Barriles susceptible control showed grade reaction of 8. In several lines it was observed an apparent reaction of hyper-sensitivity to the web blight.

scholarly journals Pre-harvest Sprouting Tolerance of Triticale Genotypes in Brazil

2020 ◽  
Vol 13 (1) ◽  
pp. 53
Author(s):  
Carlos Henrique dos Santos Fernandes ◽  
Klever Márcio Antunes Arruda ◽  
Inês Cristina Batista da Fonseca ◽  
Claudemir Zucareli ◽  
Juliana Sawada Buratto
Keyword(s):  
Genetic Variability ◽  
Germination Percentage ◽  
Experimental Unit ◽  
Falling Number ◽  
Growing Seasons ◽  
Randomized Design ◽  
Main Factors ◽  
Completely Randomized Design ◽  
Triticosecale Wittmack ◽  
X Triticosecale Wittmack

Pre-harvest sprouting (PHS) represents one of the main factors, which causes yield, technological and physiological losses in triticale seeds (X Triticosecale Wittmack). This work aimed to rate the variability and identify potential pre-harvest sprouting tolerant sources in triticale genotypes. Based on that, 32 triticale and three wheat genotypes were sown in 2016, 2017 and 2018 growing seasons, in Londrina-PR, Brazil. After the ears harvesting, these were submitted to simulate raining, for sprouting induction, through nebulization in a greenhouse. After nebulization, ears were sun dried, later hand threshed to determain, grain germination percentage (GERM) and hectoliter weight (HW). Additionally, it was determined grains HW of ears, whom were not submitted to nebulization, as well as the whole meal flour falling number (FN). The experiment design was completely randomized design, with two replications, and the experimental unit was made of 20 ears. The data collected were subjected to analysis of variance (ANOVA) and Scott-Knott test. Frontana, ND 674 and Quartzo are a source of tolerance to PHS in wheat. In triticale genotypes, genetic variability was observed for GERM, FN, and HW prior and after nebulization. The triticale genotypes BRS Netuno, BRS Saturno, TCL 15116, X 092181, Tiguera 1 and Tiguera 8, where tolerant towards PHS.

scholarly journals Evaluation of Soybean Oil Formulations for Effects on Powdery Mildew and Net Photosynthetic Rates of Dogwoods

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 792A-792
Author(s):  
Adriane Cannon* ◽  
Dennis Deyton ◽  
Carl Sams ◽  
William Klingeman
Keyword(s):  
Experimental Design ◽  
Powdery Mildew ◽  
Gas Analyzer ◽  
Initial Exposure ◽  
Commercial Formulation ◽  
Randomized Design ◽  
Soy Bean Oil ◽  
Completely Randomized Design ◽  
One Year ◽  
Infrared Gas Analyzer

Two experiments were conducted in a greenhouse to evaluate soy-bean oil (SO) formulations for effects on powdery mildew (PM) and photosynthesis of dogwood trees. In the first experiment, one-year-old potted trees were sprayed with different formulations of 2% SO one day before exposure to PM. The formulations were emulsified with: teric/termul, lauriciden, lecithin, lecithin/MD 1, lecithin/MD 2, or Latron B-1956. A commercial formulation of Golden Natur'l was also used. The trees were arranged in a completely randomized design with six replications and eight treatments. In the second experiment, trees were sprayed 4 days after initial exposure to PM with the same treatments and arranged in a similar experimental design. The severity of PM infection was rated using the scale: 1 = 0%, 2 = 1% to 3%, 3 = 4% to 6%, 4 = 7% to 12%, 5 = 13% to 25%, 6 = 26% to 50%, 7 = 51% to 87%, and 8 = 88% to 100% of leaves visually displaying PM. The net photosynthetic (Pn) rates were measured using an infrared gas analyzer. In the first experiment, trees sprayed pre-inoculation with Golden Natur'l, lecithin, lecithin/MD 1, or Latron B-1956 formulation had less PM than control trees at 19 and 24 days after spraying (DAS). Pn of leaves sprayed with lecithin or Latron B-1956 formulations had 68% and 40% lower Pn rates, respectively, of the control leaves at one DAS. However, by 11 DAS, none of the SO formulations significantly affected Pn rates. Leaves of plants (expt. 2) sprayed with teric/termul, lauriciden, lecithin, and lecithin/MD 2 formulations had less PM than control trees at 28 DAS. All formulations reduced Pn rates at 6 DAS, with only Golden Natur'l treated leaves recovering to rates similar to control leaves by 15 DAS.

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