scholarly journals Iris sibirica (Iridaceae) on the territory of Western Ukraine

2020 ◽  
Vol 28 (3) ◽  
pp. 211-215
Author(s):  
K. I. Scrypec ◽  
L. O. Tasenkevich ◽  
M. M. Seniv

The state of Iris sibirica L. in the national botanical reserve "The Valley of the Irises" is characterized. In particular, it was found that I. sibirica should be classified in the group of Euro-West Siberian, and not as a Euro-Siberian or even Eurasian species. Phenological rhythms and peculiarities of fruiting have been studied. It is established that the duration of the vegetation period of I. sibirica lasts 187–246 days. The most important stages of the reproductive cycle of I. sibirica (structure of inflorescences, flowers, fruits and seeds, phenology, seed productivity) have been studied. We first discovered that on the inner surface of the flower tube there is a multilayer secretory tissue – perigonal nectar. The fruiting of I. sibirica, which lasts quite a long time: 2–3 months (60–80 days) from June to August, was studied. In this population two ways opening of the capsule were observed. Apis mellifera (Linnaeus, 1758) (honey bee) and Bombus bombus (Latreille, 1802) (bumblebee) are pollinators of I. sibirica in the reserve. The coefficient of seed productivity of I. sibirica was high and quite stable, but despite the high potential and actual seed productivity in the population there is a weak seed recovery, which is associated with high turfing and invasions of members of the phytophagous genus Ceutorhynchus. Their activity dramatically reduces the maturation and dissemination of full-fledged mature seeds due to damage to flowers, capsules and seeds in them. However, the population of I. sibirica in the "The Valley of the Irises" is mature, normal, with a slight predominance of young individuals, which provides it with positive dynamics.

2011 ◽  
Vol 68 (2) ◽  
pp. 255-259 ◽  
Author(s):  
Annelise de Souza Rosa ◽  
Betina Blochtein ◽  
Diego Kweco Lima

Although canola, (Brassica napus L.), is considered a self-pollinating crop, researchers have indicated that crop productivity increases as a result of honey bee Apis mellifera L. pollination. Given this crop's growing importance in Rio Grande do Sul State, Brazil, this work evaluated the increase in pod and seed productivity with respect to interactions with anthophilous insects and manual pollination tests. The visiting frequency of A. mellifera was correlated with the crop's blooming progression, and productivity comparisons were made between plants visited by insects, manually pollinated plants (geitonogamy and xenogamy) and plants without pollination induction. Pod set and seed production per plant were determined for each treatment. Among the 8,624 recorded flower-visiting insects, Hymenoptera representatives were the most prevalent (92.3%), among which 99.8% were A. mellifera. The correlation between these bees and blooming progression was positive (r = 0.87; p = 0.002). Pollination induction increased seed productivity from 28.4% (autogamy) to 50.4% with insect visitations, as well as to 48.7 (geitonogamy) and to 55.1% (xenogamy) through manual pollination.


1999 ◽  
Vol 47 (3) ◽  
pp. 319-324 ◽  
Author(s):  
L. Békési ◽  
Brenda V. Ball ◽  
M. Dobos-Kovács ◽  
T. Bakonyi ◽  
M. Rusvai

Viruses of the honey bee have been known for a long time; however, recently the attention of scientists and apiculturalists has turned towards the relationship between these viruses and the parasitic miteVarroa jacobsoni. Although clinical symptoms indicated the presence of some of the viruses of bees in Hungary, none have previously been isolated or identified. During July unusual adult bee and brood mortality was observed in some colonies of an apiary in Budapest known to be infested withVarroa jacobsoni. Large amounts of acute paralysis virus (APV) were detected serologically in healthy honey bee pupae killed by the injection of a bacteria-free extract of diseased adult bees. Crystalline arrays of 30 nm particles were seen in ultrathin sections of the tissues of injected pupae and naturally infected adult bees. In spite of the application of acaricide treatments the bee population in several colonies had collapsed by the end of summer and the apiary suffered severe wintering losses.


2020 ◽  
Vol 7 (1) ◽  
pp. 26-35
Author(s):  
Suman Bhattarai ◽  
Subodh Raj Pandey ◽  
Santosh Kumar Bhattarai ◽  
Rupak Karn ◽  
Suraj Gurung ◽  
...  

2017 ◽  
Vol 6 (1) ◽  
pp. 21-29
Author(s):  
Adel Elbassiouny ◽  
Mohamed EL-Sherif ◽  
Sameh Sawires
Keyword(s):  

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