scholarly journals Suitability of Citrus Species as Hosts of Sphaeropsis Tumefaciens Hedges.

1969 ◽  
Vol 69 (1) ◽  
pp. 57-61
Author(s):  
S. D. Rodríguez ◽  
R. Rodríguez ◽  
P. L. Meléndez
Keyword(s):  
Disease Index ◽  
Sour Orange ◽  
Citrus Species ◽  
Disease Symptoms ◽  
Rough Lemon

The reaction of eight species of citrus and the chironja hybrid to inoculations with S. tumefaciens was evaluated in the greenhouse. All hosts developed disease symptoms, but their responses varied. Rough lemon was the host most severely affected by this pathogen, showing dieback symptoms 60 days after inoculation. The lowest disease index was observed in sour orange.

Effect of calcium sprays on the severity of internal browning in Brussels sprouts

1971 ◽  
Vol 11 (48) ◽  
pp. 123 ◽  
Author(s):  
CR Millikan ◽  
EN Bjarnason ◽  
BC Hanger
Keyword(s):  
Virus Infection ◽  
Sweet Orange ◽  
Poor Performance ◽  
Sour Orange ◽  
Brussels Sprouts ◽  
Carrizo Citrange ◽  
Rough Lemon ◽  
The Poor ◽  
Internal Browning ◽  
Cleopatra Mandarin

Five scions and ten rootstocks were tested in an eight-year trial at Irymple, near Mildura, Victoria. The scions were two old-line Lisbons, a nucellar Eureka, and two old-line Eurekas. Cumulative yields averaged for the ten rootstocks and expressed as a percentage of the best scion were : Rix Lisbon 100, Doncaster Lisbon 99, Frost Nucellar Eureka 95, Rodwell Eureka 89, and Villa Franca Eureka 73. The rootstocks, with their percentage yields in parentheses, were : Rough lemon (100), Cavanagh sweet orange (90), Symons sweet orange (84), Marsh grapefruit (73, Cox sweet orange (74), Cleopatra mandarin (72). Seville sour orange (721, Sampson tangelo (69), Emperor mandarin (69), and Carrizo citrange (30). The poor performance of Carrizo citrange is discussed in terms of virus infection and incompatibility. The incidence and importance of scion overgrowth is also reported and discussed.

Impairment of leaf hydraulics in young plants of Citrus aurantium (sour orange) infected by Phoma tracheiphila

2007 ◽  
Vol 34 (8) ◽  
pp. 720 ◽  
Author(s):  
Fabio Raimondo ◽  
Francesco Raudino ◽  
Santa Olga Cacciola ◽  
Sebastiano Salleo ◽  
Maria Assunta Lo Gullo
Keyword(s):  
Conidial Suspension ◽  
Sour Orange ◽  
Citrus Aurantium ◽  
Citrus Species ◽  
Leaf Hydraulics ◽  
Primary Mechanism ◽  
Major Vein ◽  
Leaf Infection ◽  
Phoma Tracheiphila ◽  
The Impact

Phoma trachephila (Petri) Kantschaveli et Gikachvili causes dieback of several Citrus species. The impact of this fungus on leaf hydraulics was studied in Citrus aurantium L. (sour orange) with the aim of identifying the primary mechanism of damage to leaves. Leaves inoculated with a conidial suspension were measured for conductance to water vapor (gL) and specific hydraulic conductance (Kleaf) every 3 days after inoculation. The earliest symptom of infection consisted of vein chlorosis. Functional vein density (FVD) was monitored and microscopic observations were made of major vein conduits. Impairment of vein hydraulics started 25 days after inoculation with a losses of Kleaf of 40% and gL of ~60%. Most minor veins within chlorotic areas were no longer functioning and some conduits of the major veins showed digested interconduit pits leading to vein cavitation. The close Kleaf–FVD relationship revealed that vein impairment caused drop of Kleaf and, consequently, of gL at chlorotic areas. Leaf infection was focused to veins that were first forced to embolise and then invaded by fungal hyphae. The vein embolism due to the Phoma amplifies the native dominant hydraulic resistance of leaf veins, and leads ultimately to early shedding of infected leaves.

scholarly journals Occurrence of Sharp Eyespot in Spring Cereals Grown in Some Regions of Poland

2010 ◽  
Vol 50 (4) ◽  
pp. 505-512 ◽  
Author(s):  
Grzegorz Lemańczyk
Keyword(s):  
Significant Variation ◽  
Disease Index ◽  
Pcr Assay ◽  
Disease Symptoms ◽  
Previous Crop ◽  
Sharp Eyespot ◽  
Significant Difference ◽  
Fungicidal Treatment ◽  
Commercial Farms ◽  
Spring Cereals

Occurrence of Sharp Eyespot in Spring Cereals Grown in Some Regions of PolandOccurrence of sharp eyespot was determined in the period 2006-2008, on commercial fields of spring cereals, localized in northern and central Poland. Percent of infected stems, and the disease index were evaluated. Occurrence of sharp eyespot on spring cereals, especially on oat, was low. Slight infection was mostly observed. In some farm fields, disease symptoms were not observed. A significant difference in the occurrence of sharp eyespot on barley in respective years was noted. On commercial farms, the effect of previous crop and fungicidal treatment on occurrence of sharp eyespot was not observed. Significant variation of the infection was noted only for barley. Presence ofRhizoctonia cerealisandR. solaniin the damaged tissues was confirmed by mycological analysis as well as PCR assay.

scholarly journals Incidence of Plant Viral Disease Symptoms and Their Transmission Agents in Dutsin-Ma Metropolis

2019 ◽  
pp. 1-9
Author(s):  
A. A. Bem ◽  
M. Toryila ◽  
T. M. Anakaa ◽  
J. B. Orpin
Keyword(s):  
Zea Mays ◽  
Vigna Unguiculata ◽  
Carica Papaya ◽  
Viral Disease ◽  
Disease Index ◽  
Abelmoschus Esculentus ◽  
Chi Square ◽  
Index Method ◽  
Disease Symptoms ◽  
Chi Square Analysis

This work explores the incidence of plant viral disease symptoms as well as their transmission agents in Dutsin-Ma Local Government Area Katsina State, Nigeria. The studied diseased plants were identified while diseases were based on visual inspection using characteristic symptoms. Organisms associated with such symptoms were collected by handpicking, shacking/beating and tissue teasing methods. Identification was done using a standard voucher. Incidence of plants with viral symptoms was determined by plant disease index method. Chi square analysis was used to ascertain significant differences (P≥ 0.05) of plants showing viral symptoms. Results shows that plants with viral symptoms included Amaranthus sp. (Amaranthus), Vigna unguiculata (cowpea), Zea mays (maize), Abelmoschus esculentus (okra), Carica papaya (pawpaw) and Capsicum sp (pepper). Studies also reveal Myzus persicae (aphids), Frankinella occidentalis (thrips), Bemisa tabaci (whitefly), Peregrinus maydis (leafhoppers) and Pseudococcidae (mealy bugs) as organisms associated with diseased plants with viral symptoms. Disease index showed Amaranthus spp. 63%, Vigna unguiculata 84%, Zea mays 73%, Abelmoschus esculentus, Carica papaya and Capsicum spp. 100%. Incidence rate varied significantly (P≥ 0.05) in the various locations surveyed. Further studies need to be carried out to identify the individual viruses.

scholarly journals Unraveling the cryptic genetic variation and population structure of the citrus genotypes with unknown origin

Genetika ◽  
2020 ◽  
Vol 52 (1) ◽  
pp. 291-309
Author(s):  
Abouzar Abouzari ◽  
Mahmood Solouki ◽  
Behrouz Golein ◽  
Barat Fakheri ◽  
Atefeh Sabouri ◽  
...  
Keyword(s):  
Unknown Origin ◽  
Aflp Analysis ◽  
Genetic Introgression ◽  
Sour Orange ◽  
Genetic Composition ◽  
Citrus Species ◽  
Ssr Loci ◽  
Polymorphic Bands ◽  
Main Determinants ◽  
High Diversity

The high diversity of Citrus genotypes can increase the probability of identifying new genetic makeups and even desirable traits. Hence, 76 genotypes with unknown origin and 34 known cultivars from several Citrus species were analyzed by SSR and AFLP markers. Overall, 326 alleles and 545 polymorphic bands were respectively scored for 28 SSR loci and 25 AFLP primer-enzyme combinations. The results of various analyses accomplished with SSR markers were in agreement with AFLP. Accordingly, the true species of citron, mandarin, and pummelo were nested into separate groups. In the studied germplasm, we succeeded in tracking three cryptic origin genomes (2 in SSR and 1 in AFLP analysis) which were distinct from 3 true species, and, interestingly, they contributed to the genetic composition of some control cultivars. The results suggested that the interspecific hybridization and genetic introgression were the main determinants of the Citrus genotypes genetic composition. Hereupon, the share of citron in 36%, mandarin in 34%, and pummelo in 22% of selected accessions estimated more than 50%. Despite the controversy about the origin of lemon and sour orange, the results of different grouping methods suggested that lemon had more affinity with lime, and the genetic contribution of mandarin in sour orange was stronger than that of pummelo.

Comparison of lemon varieties and rootstocks at Mildura, Victoria

1971 ◽  
Vol 11 (48) ◽  
pp. 118
Author(s):  
LM Stafford
Keyword(s):  
Virus Infection ◽  
Sweet Orange ◽  
Poor Performance ◽  
Sour Orange ◽  
Carrizo Citrange ◽  
Rough Lemon ◽  
The Poor ◽  
Cleopatra Mandarin

Five scions and ten rootstocks were tested in an eight-year trial at Irymple, near Mildura, Victoria. The scions were two old-line Lisbons, a nucellar Eureka, and two old-line Eurekas. Cumulative yields averaged for the ten rootstocks and expressed as a percentage of the best scion were : Rix Lisbon 100, Doncaster Lisbon 99, Frost Nucellar Eureka 95, Rodwell Eureka 89, and Villa Franca Eureka 73. The rootstocks, with their percentage yields in parentheses, were : Rough lemon (100), Cavanagh sweet orange (90), Symons sweet orange (84), Marsh grapefruit (73, Cox sweet orange (74), Cleopatra mandarin (72). Seville sour orange (721, Sampson tangelo (69), Emperor mandarin (69), and Carrizo citrange (30). The poor performance of Carrizo citrange is discussed in terms of virus infection and incompatibility. The incidence and importance of scion overgrowth is also reported and discussed.

Evaluation of rootstocks for Eureka and Lisbon lemons in replant ground in New South Wales

1992 ◽  
Vol 32 (2) ◽  
pp. 205
Author(s):  
RA Sarooshi ◽  
P Broadbent
Keyword(s):  
Fruit Quality ◽  
New South ◽  
New South Wales ◽  
Poncirus Trifoliata ◽  
Citrus Limon ◽  
Sour Orange ◽  
Rough Lemon ◽  
South Wales ◽  
Graft Compatibility ◽  
Large Flower

The yield, growth, fruit quality, and graft compatibility of 2 lemon cultivars Eureka and Lisbon [Citrus limon (L.) Bum. f.], budded onto several new rootstocks, were studied in replant ground.Promising rootstocks for Eureka lemon were 2 new hybrids bred at Gosford, New South Wales, 3798 (Scarlet mandarin x Poncirus trifoliata) and 4017 (Smooth Seville x P. trifoliata), and also Benton citrange and Nelspruit hybrid 639. Trees on the sour orange group of rootstocks including Xingshan, Dai Dai and Baggan yielded 44-63% less than trees on rough lemon rootstocks; but their fruit quality, as evidenced by juice per cent, OBrix, and citric acid (kg/t), was better. The performance of Lisbon lemon was tested on 10 selections of F'. trifoliata, and although trees on Flying Dragon were smaller and yielded about 50% less than on Swingle, Christiansen, Large Flower, and selection 22, results were not significantly (P<0.05) different.

An aggressive vascular-inhabiting Phoma (Phoma tracheiphila f. sp. chrysanthemi nov. f. sp.) weakly pathogenic to chrysanthemum

1985 ◽  
Vol 63 (10) ◽  
pp. 1730-1735 ◽  
Author(s):  
Kenneth F. Baker ◽  
Lily H. Davis ◽  
Stephen Wilhelm ◽  
William C. Snyder
Keyword(s):  
Verticillium Wilt ◽  
Home Gardens ◽  
Infested Soil ◽  
Sour Orange ◽  
Rough Lemon ◽  
Decline Disease ◽  
Phoma Tracheiphila ◽  
Intact Roots ◽  
Mal Secco ◽  
Mycelial Development

A form of Phoma tracheiphila (Petri) Kant. & Gik., newly designated as f. sp. chrysanthemi Baker et al., massively invades the phloem and xylem and to a lesser extent the cortex and pith of chrysanthemum plants but causes only slight injury in the first season. However, infected plants either produce weak shoots the following year or commonly fail to resume growth. Injury appears to result from depletion of photosynthates and nutrients rather than from vascular plugging or toxins. Infection occurs through intact roots or through wounds of roots or stems, and the pathogen spreads to the top of 120-cm stems in 3 months. Infection occurs readily from 10–29.4 but most abundantly at 10–21° C. Mycelial development in the stems is retarded at 10 and is optimal at 21° C. This Phoma decline disease was prevalent in commercial and home chrysanthemum plantings in California in 1948–1956, but it has since been controlled by the annual planting of healthy cuttings in fumigated soil, as practiced for control of verticillium wilt. In home gardens the disease may cause severe losses if plants are grown as perennials, but if healthy cuttings are planted annually, the disease will be minimal even in plants grown in infested soil. The pathogen is indistinguishable morphologically from Phoma tracheiphila f. sp. tracheiphila Baker et al., cause of "mal secco" of citrus, but will not infect sour orange or rough lemon plants.

Glomus intraradix effects on citrus rootstock seedling growth in various potting media

1992 ◽  
Vol 118 (3) ◽  
pp. 315-323 ◽  
Author(s):  
S. Nemec
Keyword(s):  
Plant Growth ◽  
Linear Models ◽  
Fine Sand ◽  
Root Weight ◽  
Sour Orange ◽  
Rough Lemon ◽  
Wood Shavings ◽  
Citrus Rootstock ◽  
Potting Media ◽  
Glomus Intraradix

SUMMARYFive potting media components mixed in various combinations and in various percentages of one with another (0, 14·3, 29, 42, 57, 71 and 100% by volume of the second component with the first) were inoculated with Glomus intraradix in six experiments. Seedlings of citrus rootstocks were grown from seed in these mixes. Sour orange in inoculated peat plus vermiculite, Astatula fine sand plus vermiculite, and peat plus Perlite® in all percentage combinations grew c. two- to threefold taller than noninoculated control plants. Up to twofold growth increases of sour orange occurred in vermiculite amended with wood shavings. The best evidence for fungus-mediated plant growth occurred in Astatula fine sand amended with 29–71% Perlite, and the roots in that combination had the highest percentage of infection. In another experiment in which Astatula fine sand was amended with up to 16% of an acid peat, ratios of inoculated rough lemon plant growth to controls decreased as the peat content in the medium increased. Top and root weight ratios of inoculated:control seedlings in the six experiments did not fit four simple linear models.

Sign in / Sign up

Export Citation Format

Share Document