Phomopsis Canker of European Black Alder Found in Kentucky Seed-Production Areas

Plant Disease ◽  
1983 ◽  
Vol 67 (6) ◽  
pp. 691 ◽  
Author(s):  
S. W. Oak
Keyword(s):  
Seed Production ◽  
Black Alder ◽  
Production Areas

Natural establishment of Pinus spp. around seed production areas and orchards

2021 ◽  
Vol 494 ◽  
pp. 119333
Author(s):  
Magda Paula dos Santos ◽  
Marcio José de Araujo ◽  
Paulo Henrique Müller da Silva
Keyword(s):  
Seed Production ◽  
Natural Establishment ◽  
Pinus Spp ◽  
Production Areas

scholarly journals First Report of Umbel Browning and Stem Necrosis Caused by Diaporthe angelicae on Carrot in France

Plant Disease ◽  
2014 ◽  
Vol 98 (3) ◽  
pp. 421-421 ◽  
Author(s):  
L. Ménard ◽  
P. E. Brandeis ◽  
P. Simoneau ◽  
P. Poupard ◽  
I. Sérandat ◽  
...  
Keyword(s):  
Seed Production ◽  
White Light ◽  
Agar Medium ◽  
Malt Agar ◽  
Universal Primers ◽  
Conidial Suspension ◽  
First Report ◽  
Daucus Carota L ◽  
Cropping Seasons ◽  
Production Areas

In 2011, carrot (Daucus carota L.) seed production occurred on 2,900 ha, which accounts for approximately 25% of the area devoted to the production of vegetable fine seeds. Since 2007, symptoms of umbel browning have been regularly observed in carrot production areas located in the central region. Initially, triangular necrotic lesions appeared on carrot umbels that later spread to the entire umbels and often progressed to the stems. Diseased umbels became dried prematurely, compromising seed development. The loss in seed production was estimated at approximately 8% of the harvested carrot umbels during the cropping seasons of spring and summer 2007 and 2008 in France. In collaboration with seed companies, diseased carrot stems were collected from seven fields of seed production (eight plants per field) and a fungus was isolated from the tissue. The cultures were grown on malt (2%) agar (1.5%) medium and incubated for 2 weeks at 22°C in darkness. Young fungal colonies were white and a brownish green pigmentation developed when the colonies became older. The same color was observed from the top and on the reverse of the colonies. To induce sporulation, isolates were grown on water agar (1.5%) medium in the presence of carrot stem fragments for 1 week at 22°C in darkness, followed by 1 week at 22°C in white light under a 16-h photoperiod. Pycnidia were produced on stem fragments and contained alpha and beta conidia typical of the genus Diaporthe (2). Alternatively, pycnidia were also obtained on malt agar medium after 2 weeks of culture at 25°C in white light under a 12-h photoperiod. The size of alpha and beta conidia was 6.3 ± 0.5 × 2.3 ± 0.4 μm and 23.3 ± 1.8 × 0.9 ± 0.2 μm, respectively (n = 170). In order to confirm the identification at the genus level and determine the species, DNA was extracted from the mycelium of three representative isolates and the ITS regions of the ribosomal DNA were amplified using universal primers (1). The sequences of the amplified products (GenBank Accession Nos. KF240772 to KF240774) were 100% identical with the ITS sequence of a Diaporthe angelicae isolate deposited in the NCBI database (CBS 111592 isolate, KC343027). To confirm pathogenicity, the three isolates of D. angelicae were inoculated on carrot umbels in the greenhouse. A total of nine plants were inoculated (three plants per isolate). Using a micropipette, 10 μl of a conidial suspension containing alpha and beta conidia (105 conidia mL–1) were deposited at the base of the primary umbel and two secondary umbels, which were wounded before inoculation using a scalpel blade. Seven inoculated plants developed triangular, necrotic lesions that were typical umbel browning. D. angelicae was re-isolated on malt agar medium from the inoculated diseased carrot umbels. To our knowledge, this is the first report of D. angelicae in carrot cultivated for seed production in France. The disease resembles the lesions described in the Netherlands in 1951 on carrot inflorescence caused by Phomopsis dauci (3). In future experiments, it would be crucial to precisely determine if D. angelicae could be transmitted to the seeds. References: (1) M. A. Innis et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (2) J. M. Santos and A. J. L. Philips. Fungal Divers. 34:111, 2009. (3) J. A. von Arx. Eur. J. Plant Pathol. 57:44, 1951.

scholarly journals Shortleaf Pine Seed Production in Natural Stands in the Ouachita and Ozark Mountains

1996 ◽  
Vol 20 (2) ◽  
pp. 74-80 ◽  
Author(s):  
Michael G. Shelton ◽  
Robert F. Wittwer
Keyword(s):  
Seed Production ◽  
Natural Regeneration ◽  
Stand Age ◽  
Good Seed ◽  
Pinus Echinata ◽  
Ozark Mountains ◽  
Shortleaf Pine ◽  
Natural Stands ◽  
Seed Crops ◽  
Production Areas

Abstract Seed production of shortleaf pine (Pinus echinata Mill.) was monitored from 1965 to 1974 to determine the periodicity of seed crops in both woods-run stands and seed-production areas. One bumper and two good seed crops occurred during the 9-yr period. The two largest crops occurred in successive years, then seed production was low for 4 yr before another good crop occurred. Mean annual seed production ranged from 84,000/ac in the western Ouachitas to 167,000/ac in seed-production areas in the southern Ozarks. Certain stand-level variables significantly influenced seed production. Seed production was positively related to stand age and negatively related to pine and hardwood basal areas; although frequently significant, no consistent relationship occurred with stand elevation. Results indicate that shortleaf pine seed production will usually be adequate for natural regeneration within most of the study area. South. J. Appl. For. 20(2):74-80.

Effects of fenced seed production areas and restoration treatments on the size and composition of the native grass seedbanks in moderately degraded rangelands in semiarid Australia

2016 ◽  
Vol 38 (1) ◽  
pp. 47
Author(s):  
Judith M. Bean ◽  
Gavin J. Melville ◽  
Ronald B. Hacker ◽  
Sharon Anderson ◽  
Alicia Whittington ◽  
...  
Keyword(s):  
Seed Production ◽  
Positive Influence ◽  
Native Grass ◽  
North West ◽  
South Wales ◽  
Red Earth ◽  
Preferred Species ◽  
Study Sites ◽  
Production Areas ◽  
And Control

Seed production areas containing populations of native grasses were fenced on topographically high areas at two study sites in the semiarid rangelands of north-west New South Wales, Australia. The surrounding slopes were initially almost bare of pastorally preferred grasses. Three restoration treatments (control, mechanical pitting, and contour-aligned branch piles) were established on these surrounding slopes and the size and composition of the native grass seedbanks determined. A positive influence of the seed production areas mostly occurred within 15 m of the fence and was probably insignificant beyond 33 m at both sites. On a hard-setting red earth site, the size of the native grass seedbank in all three treatments increased over 2 years with the greatest increase under the piles of branches and smaller increases in the pitting and control treatments. The piles of branches preferentially incorporated seed of the pastorally preferred species Monachather paradoxus Steud into the seedbank whereas pits preferentially incorporated seed of the pastorally unpreferred species Aristida jerichoensis (Domin) Henrad. Evidence generally pointed to incoming seed rain rather than the seedbank as the main source of new seedlings. On a medium-textured lithosol site neither the pits nor the branches treatment was effective in enhancing either the size or composition of the seedbank; in fact the piles of branches resulted in a decrease in its size.

An evaluation of the genetic structure of seed sources and the maintenance of genetic diversity during establishment of two yellow box (Eucalyptus melliodora) seed-production areas

2015 ◽  
Vol 63 (5) ◽  
pp. 455 ◽  
Author(s):  
Linda M. Broadhurst ◽  
Graham Fifield ◽  
Bindi Vanzella ◽  
Melinda Pickup
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Seed Production ◽  
Significant Loss ◽  
Evolutionary Potential ◽  
Seed Collection ◽  
Seed Sources ◽  
Significant Difference ◽  
Genetic Bottlenecks ◽  
Production Areas

Vegetation clearing and land-use change have depleted many natural plant communities to the point where restoration is required. A major impediment to the success of rebuilding complex vegetation communities is having regular access to sufficient quantities of high-quality seed. Seed-production areas (SPAs) can help generate this seed, but these must be underpinned by a broad genetic base to maximise the evolutionary potential of restored populations. However, genetic bottlenecks can occur at the collection, establishment and production stages in SPAs, requiring genetic evaluation. This is especially relevant for species that may take many years before a return on SPA investment is realised. Two recently established yellow box (Eucalyptus melliodora A.Cunn. ex Schauer, Myrtaceae) SPAs were evaluated to determine whether genetic bottlenecks had occurred between seed collection and SPA establishment. No evidence was found to suggest that a significant loss of genetic diversity had occurred at this stage, although there was a significant difference in diversity between the two SPAs. Complex population genetic structure was also observed in the seed used to source the SPAs, with up to eight groups identified. Plant survival in the SPAs was influenced by seed collection location but not by SPA location and was not associated with genetic diversity. There were also no associations between genetic diversity and plant growth. These data highlighted the importance of chance events when establishing SPAs and indicated that the two yellow box SPAs are likely to provide genetically diverse seed sources for future restoration projects, especially by pooling seed from both SPAs.

SOIL APPLICATION OF CARBOFURAN TO CONTROL SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE), IN A MANAGED WHITE SPRUCE SEED PRODUCTION AREA

1981 ◽  
Vol 113 (10) ◽  
pp. 949-951 ◽  
Author(s):  
W. H. Fogal ◽  
D. A. Winston ◽  
S. M. Lopushanski ◽  
D. A. MacLeod ◽  
A. J. Willcocks
Keyword(s):  
Seed Production ◽  
Picea Glauca ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
White Spruce ◽  
Cone Production ◽  
Seed Supply ◽  
Current Outbreak ◽  
Production Area ◽  
Production Areas

White spruce, Picea glauca (Moench) Voss, is a major commercial tree species used in reforestation programs throughout Canada, and seed requirements cannot be met in some years because of insect damage and the periodic nature of cone crops. The spruce budworm, Choristoneura fumiferana (Clem.), feeds on buds and cones of its hosts, causing a pronounced decrease in cone production (Schooley 1978). A current outbreak in northeastern Ontario poses a serious threat to white spruce seed supply from high value, managed seed production areas. Therefore, in 1979, we began an experiment to determine whether carbofuran, a systemic insecticide, could be used to protect buds and cones when applied to soil. We chose carbofuran because it has proved successful for control of some insects in seed orchards in the southeastern United States (DeBarr 1978)

scholarly journals Prevalence of Acidovorax citrulli in Commercial Cucurbit Seedlots During 2010–2018 in China

Plant Disease ◽  
2020 ◽  
Vol 104 (1) ◽  
pp. 255-259 ◽  
Author(s):  
Yanli Tian ◽  
Yuqiang Zhao ◽  
Jiaju Zhou ◽  
Ting Sun ◽  
Xue Luo ◽  
...  
Keyword(s):  
Seed Production ◽  
Inner Mongolia ◽  
Fruit Production ◽  
Colony Pcr ◽  
Primary Inoculum ◽  
Bacterial Fruit Blotch ◽  
Growing Seasons ◽  
Acidovorax Citrulli ◽  
High Prevalence ◽  
Production Areas

Acidovorax citrulli is the causal agent of bacterial fruit blotch (BFB), a serious threat to cucurbit fruit and seed production worldwide. In recent years, the BFB has spread to many areas of China, mainly via the inadvertent distribution of contaminated commercial seeds. To assess the prevalence of seedborne A. citrulli in commercial watermelon and other cucurbitaceous seedlots in China, a 9-year survey was conducted between 2010 and 2018. A total of 4,839 seedlots of watermelon and other cucurbitaceous species were collected from 13 major seed production areas of China and tested by a semiselective media-based colony PCR technique for A. citrulli. Overall, A. citrulli was detected in 18.00% (871/4,839) of all cucurbitaceous seedlots. The bacterium was detected in 21.59% (38/176), 19.19% (33/172), 23.44% (214/913), 40.76% (247/606), 13.28% (85/640), 15.40% (95/617), 13.25% (73/551), 8.03% (48/598), and 6.71% (38/566) of all commercial seedlots tested from the 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, and 2018 growing seasons, respectively. Additionally, the prevalence of A. citrulli in cucurbit seedlots was determined for different seed production areas. The prevalence of A. citrulli in cucurbitaceous seedlots produced in Xinjiang, Gansu, Ningxia, Inner Mongolia, and 9 other provinces was 18.76% (582/3103), 26.34% (103/391), 21.47% (82/382), 11.11% (14/126), and 10.75% (90/837), respectively. This is the first survey for A. citrulli in commercial cucurbit seeds in China, and the relatively high prevalence suggests that commercial seeds represent a substantial source of primary inoculum that can threaten cucurbit seed and fruit production in China.

RELATIONSHIP BETWEEN CONE CROP SIZE AND CONE DAMAGE BY INSECTS IN RED PINE SEED-PRODUCTION AREAS

1971 ◽  
Vol 103 (4) ◽  
pp. 617-621 ◽  
Author(s):  
William J. Mattson
Keyword(s):  
Seed Production ◽  
Red Pine ◽  
Insect Damage ◽  
Crop Size ◽  
Pine Cone ◽  
Pine Cones ◽  
Production Areas ◽  
Cone Damage

AbstractAnnual cone abundance and insect damage to cones are highly variable in red pine seed-production areas. Cone crop size fluctuates almost unpredictably from year to year, but the number of insect-attacked cones tends to increase annually unless limited by cone abundance. Sixty-six per cent of the variation in cone damage can be associated with variations in cone abundance. This information, coupled with the fact that red pine cone insects are almost entirely dependent on red pine cones for food, implies that crop size is highly important in regulating populations of cone insects. Insects will be most devastating in areas where crop size varies little from year to year.

scholarly journals Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L.) in Alfalfa Seed Production Areas in the United States

PLoS ONE ◽  
2015 ◽  
Vol 10 (12) ◽  
pp. e0143296 ◽  
Author(s):  
Stephanie L. Greene ◽  
Sandya R. Kesoju ◽  
Ruth C. Martin ◽  
Matthew Kramer
Keyword(s):  
United States ◽  
Medicago Sativa ◽  
Seed Production ◽  
The United States ◽  
Alfalfa Seed ◽  
Production Areas ◽  
Feral Alfalfa
Sign in / Sign up

Export Citation Format

Share Document