Evaluation of seedling emergence and relative DNA content under dry soil conditions of wildFestuca arundinaceapopulations collected in Iran

2015 ◽  
Vol 61 (1) ◽  
pp. 6-14 ◽  
Author(s):  
Iman Rohollahi ◽  
Nayer Azam Khoshkholghsima ◽  
Toshihiko Yamada ◽  
Mohsen Kafi ◽  
Yoichiro Hoshino ◽  
...  

1951 ◽  
Vol 4 (3) ◽  
pp. 211
Author(s):  
GC Wade

The disease known as white root rot affects raspberries, and to a less extent loganberries, in Victoria. The causal organism is a white, sterile fungus that has not been identified. The disease is favoured by dry soil conditions and high soil temperatures. It spreads externally to the host by means of undifferentiated rhizomorphs; and requires a food base for the establishment of infection. The spread of rhizomorphs through the soil is hindered by high soil moisture content and consequent poor aeration of the soil.



1975 ◽  
Vol 65 (3) ◽  
pp. 359-372 ◽  
Author(s):  
A. B. S. King

AbstractThe size and occurrence of the first brood of adults of Aeneolamia varia saccharina (Dist.) are examined in relation to the pattern of egg eclosion and rainfall. The proportion of eggs hatching within a month of oviposition in the laboratory (short-period eggs) decreased from over 90% in August to less than 20% in January, but the incubation periods of the remaining, long-period eggs were longest in those laid during October and November. The overall hatching distributions tended to be bimodal with most eggs hatching during the early months of the year under moist conditions at 26°C. Dry soil conditions delay eclosion, and eggs obtained from fields during the dry season and then incubated under moist conditions tended to hatch at the normally expected time of the first rains in May. The numbers of eggs expected to produce the first brood, computed from laboratory hatching data and estimates of the numbers and fecundities of froghoppers during the second, third and fourth broods, were less than the actual numbers sampled just before the first rains. There was a close relationship between the first rainfall of over one inch within 48 h and adult emergence 27 and 34 days later, and 85% of field egg populations in May had hatched and/or died by the week after the first rains. However some variation in the date of their occurrence accounted for non-synchrony of first broods over the region. The numbers of diapause eggs in fields sampled during the dry season failed to give a good predictive relationship with first brood adult populations, probably because of density dependent mortality of eggs or hatchling nymphs.



2011 ◽  
Vol 39 (No. 2) ◽  
pp. 59-67 ◽  
Author(s):  
I. Doležalová ◽  
A. Lebeda ◽  
M. Dziechciarková ◽  
E. Křístková ◽  
D. Astley ◽  
...  

Fifty one accessions of nineteen Lactuca species, the hybrid L. serriola × L. sativa and the related species Mycelis muralis were evaluated for morphological variability, esterase (EST) polymorphism, Amplified Fragment Length Polymorphism (AFLP) and relative DNA content. Sixteen Lactuca accessions were classified taxonomically on the basis of morphology, isozyme analysis and AFLP. Twenty-eight bands (isoforms) of EST were recorded allowing 82% of accessions to be distinguished. The relative DNA content, measured using flow-cytometry (DAPI staining), ranged from 2.02 pg in L. capensis to 17.96 pg in L. canadensis. The results from AFLP analysis and the relative DNA content measurement corresponded well with recent taxonomic classification of the genus Lactuca.  



Weed Science ◽  
1983 ◽  
Vol 31 (2) ◽  
pp. 271-274 ◽  
Author(s):  
John K. Soteres ◽  
Don S. Murray ◽  
Eddie Basler

Absorption of 2,4-D [(2,4-dichlorophenoxy) acetic acid], dicamba [3,6-dichloro-o-anisic acid], and the isopropylamine salt of glyphosate [N-(phosphonomethyl) glycine] by excised honeyvine milkweed [Cynanchum laeve(Michx.) Pers.] leaves was determined. Experimental variables included leaf position (terminal vs. basal), a surfactant, 4-isopropenyl-1-methylcyclohexane plus unspecified emulsifiers (SA-77), and leaf collection dates. Absorption of the three herbicides by terminal and basal leaves was increased by the addition of the surfactant. However, the surfactant increased absorption into basal leaves more than into terminal leaves. The surfactant reduced surface tension and increased drying time of water droplets on adaxial leaf surfaces by 50%. The pH of the herbicide solutions was reduced from about 5.8 to about 3.9 by SA-77. Absorption of all three herbicides was greater into terminal than into basal leaves when the surfactant was not present, but the difference disappeared when the surfactant was added. Generally, no differences were observed in the absorption of 2,4-D and dicamba. Glyphosate absorption was greater in terminal leaves collected after a period of adequate moisture than after a period of dry soil conditions.



1986 ◽  
Vol 72 (2) ◽  
pp. 171-177 ◽  
Author(s):  
Raffaella Uccelli ◽  
Alberto Calugi ◽  
Donato Forte ◽  
Francesco Mauro ◽  
Paolo Polonio-Balbi ◽  
...  

The relative DNA content of cellular samples from 54 patients affected by breast carcinomas and 20 affected by benign breast lesions (including 11 fibroadenomas) was measured by flow cytometry. All normal tissue samples and 17/20 (85%) specimens from benign lesions exhibited a cytometrically diploid DNA distribution, 3/20 (15%) benign lesions an abnormal DNA content, and 35/54 (65%) carcinomas at least one aneuploid cell subpopulation. Furthermore, 9/54 (17%) tumors were characterized by the presence of more than one aneuploid cell subpopulation. The results also indicate that flow cytometry can be used to recognize lymph nodes infiltrated by aneuploid cells. Statistically significant correlations were evidenced between the occurrence of aneuploidy or the ploidy level measured as DNA index and the nodal infiltration status. The percentage of S cells can also be extracted from DNA content distribution histograms. Statistically significant differences (p < 0.01) were also observed for the percentage of S cells between normal tissues (6.2±3.2 SD) and benign lesions (11.1±6.6 SD), normal tissues (6.2 ± 3.2 SD) and aneuploid tumors (19.7 ± 10.3 SD), benign lesions (11.1 ± 6.6 SD) and aneuploid tumors (19.7 ± 10.3 SD), and diploid (7.9 ± 4.0 SD) and aneuploid tumors (19.7 ± 10.3 SD).



2015 ◽  
Vol 39 ◽  
pp. 633-651 ◽  
Author(s):  
Dalia FEIZIENE ◽  
Dalia JANUSAUSKAITE ◽  
Virginijus FEIZA ◽  
Agne PUTRAMENTAITE ◽  
Ausra SINKEVICIENE ◽  
...  


2017 ◽  
Vol 63 (No. 6) ◽  
pp. 257-263 ◽  
Author(s):  
Faber Florian ◽  
Wachter Elisabeth ◽  
Zaller Johann G

Inter-rows in vineyards are commonly tilled in order to control weeds and/or to conserve water. While impacts of tillage on earthworms are well studied in arable systems, very little is known from vineyards. In an experimental vineyard, the impact of four reduced tillage methods on earthworms was examined: rotary hoeing, rotary harrowing, grubbing and no tillage. According to an erosion prevention programme, tillage was applied every other inter-row only while alternating rows retained vegetated. Earthworms were extracted from the treated inter-rows 10, 36, 162 and 188 days after tillage. Across dates, tillage methods had no effect on overall earthworm densities or biomass. Considering each sampling date separately, earthworm densities were affected only at day 36 after tillage leading to lower densities under rotary hoeing (150.7 ± 42.5 worms/m<sup>2</sup>) and no tillage (117.3 ± 24.8 worms/m<sup>2</sup>) than under rotary harrowing (340.0 ± 87.4 worms/m<sup>2</sup>) and grubbing (242.7 ± 43.9 worms/m<sup>2</sup>). Time since tillage significantly increased earthworm densities or biomass, and affected soil moisture and temperature. Across sampling dates, earthworm densities correlated positively with soil moisture and negatively with soil temperature; individual earthworm mass increased with increasing time since tillage. It was concluded that reduced tillage in vineyards has little impact on earthworms when applied in spring under dry soil conditions.



1993 ◽  
Vol 20 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Athanasios Loukas ◽  
Michael C. Quick

A simplified watershed model has been developed to examine and analyze the high rainfall response of a small, steep, and forested watershed in coastal British Columbia. Hourly data for both rainfall and streamflow are used. Rainfall is measured at five points evenly distributed throughout the watershed. The model is found to perform well and indicates that the hydrologic response of the watershed is reasonably linear, except for intense summer rainstorms under dry soil conditions. The linearity and the rapidity of the watershed response is attributed to the response of the subsurface pipeflow. An analysis of a particular case of soil pipe development shows that the pipeflow system can respond linearly and rapidly to the rainfall input. Key words: watershed modelling, hydrologic response, soil piping.



1976 ◽  
Vol 198 (2) ◽  
pp. 281-285 ◽  
Author(s):  
Philip A. Jones ◽  
John J. Gilbert


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