scholarly journals Nectar production of pear (Pyrus communis L.) cultivars

2000 ◽  
Vol 6 (3) ◽  
Author(s):  
P. Benedek ◽  
G. Kocsisné Molnár ◽  
J. Nyéki

Detailed studies were made on the nectar production of 44, 16 and 18 pear cultivars, respectively, in a cultivar collection of pear during three consecutive years with highly different weather in the blooming. Results clearly show that pear does not necessarily produce small amount of nectar as stated in the world literature. In fact, pear can produce extremely high amount of nectar sometimes much higher than other temperate zone fruit trees species but its nectar production is highly subjected to weather, first of all to air temperature. Low nectar production seems to be more frequent than high one and cold weather can prevent its nectar production at all. On the other hand, results corroborate to the earlier statements on the low sugar concentration of pear nectar. There is a highly significant negative correlation between the amount of nectar produced by pear flowers and its sugar concentration (r = -0.52, n = 291, p< 0.001 for 1996, r = -0.34, n = 197, p< 0.001 for 1998). Sugar concentration in individual flowers may be up, to 40% in exceptional cases but generally it is well below 20%. Very high figures for sugar concentration in pear nectar at the literature seem to be incomprehensible. In contrast of some earlier statement in the literature no real difference could be established in the nectar production of pear cultivars, based on much more measurements than in earlier studies. Very low sugar concentration in pear nectar can explain the fact that the overwhelming majority of honeybees are pollen gatherers at pear trees even in the case of exceptionally high nectar production.  

2000 ◽  
Vol 6 (1) ◽  
Author(s):  
P. Benedek ◽  
J. Nyéki ◽  
I. Amtmann ◽  
F. Bakcsa ◽  
J. Iváncsics ◽  
...  

Fruit tree species suffered very strong spring frosts in 1997 in Hungary. This caused partial or total damages at buds and flowers depending on site and time of blooming. It was demonstrated at a number of experiments that frost and cold weather also strongly affected the nectar production of surviving flowers. No or very little amount of nectar was measured in flowers first of all of early blooming fruit tree species (apricot) but also of pear and apple in some places. In spite of this fact intensive honeybee visitation was detected in the flowers of fruit trees that suffered partial frost damage only at those sites where honeybee colonies were placed in or at the experimental plantations and the lack of sufficient amount of nectar did not affected bee behaviour seriously on fruit flowers. This means that bad nectar production failed to affect bee visitation of fruit trees definitely. The reason for this was the fact that not only fruit trees but another early bee plants (wild plants, too) suffered frost damage. Accordingly, in lack of forage bees intensively searched for food at blooming fruit trees with some living flowers. Consequently, there was an acceptable yield at those plantations where bud and flower damage was not complete. Accordingly, intensive bee visitation (that is moving additional bee colonies to overpopulate fruit orchards with honeybees) can be an effective tool to decrease or eliminate the detrimental effect of spring frost on the yield of fruit trees where bud or fruit damage is not too high.  


2021 ◽  
Vol 10 (8) ◽  
pp. e3110816801
Author(s):  
Odair Ângelo Dalzochio ◽  
Wendel Paulo Silvestre ◽  
Gabriel Fernandes Pauletti

The necessity of controlling the vegetative growth of fruit trees is a growing concern for farmers since vigorous plants tend to have lower fruit yields. The use of chemicals that inhibit the vegetative growth of plants, such as prohexadione-calcium (PCa), an inhibitor of gibberellins which is currently used as a growth regulator for apple trees, is an agricultural practice aimed to help in reducing pruning time and cost. Pear trees grafted on vigorous rootstocks tend to present high rates of vegetative growth, hindering fruit production. Thus, this work aimed to evaluate the effect of the application of different doses of the plant growth regulator PCa on the vegetative growth, pruning time, radiation incidence, and productive and quality parameters of ‘Packham’s Triumph’ and ‘Hosui’ pears grafted on vigorous rootstocks. Two PCa applications were carried out, the first after the falling of petals (2009-10-10), and the second twenty-one days after the first (2009-11-02). The observed results showed a significant effect of PCa in reducing the vegetative growth of the pear trees and the pruning time in both cultivars. The effect on photosynthetic active radiation (PAR) was observed only in the ‘Packham’s Triumph’ variety, not being observed for the ‘Hosui’ pear trees. No statistical difference was observed relative to the quality parameters and yield of the fruits, in both cultivars, showing that PCa application has not caused any deleterious effect on fruit development.


2000 ◽  
Vol 6 (3) ◽  
Author(s):  
P. Benedek ◽  
T. Szabó ◽  
J. Nyéki

Nectar production of six quince cultivars were measured during three consecutive years. The nectar production of quince can be regarded to be small compared to other temperate zone fruit tree species since quince flowers contained 1.07 ± 0.06 mg of nectar in average. The extreme values, however, ranged between 0.1 and 7.3 mg/flower and this indicated that the nectar production was highly variable. The distribution of the nectar production was definitely skew because low values were definitely much more frequent than the highest ones. Our findings do not corroborate the earlier statements on the high sugar concentration of quince nectar. We found some 21-27% sugar in average, only. The normal distribution of the sugar concentration also indicates that the typical sugar concentration may be between 20-30%. Accordingly, the sugar concentration of quince nectar is rather low compared to other temperate zone fruit tree species (except pear). There was a significant negative correlation between the amount of nectar and its sugar concentration in quince flowers in all of the three years of the study (r= -0.51, n=37, p<0.02 in 1996, r= -0.57, n=28, p<0.1 in 1997, r= -0.35, n=9 I, p<0.001 in 1998). No definite difference was established between the nectar production of quince cultivars. Nevertheless, one cultivar tended to produce less and two other ones produced somewhat more nectar in average than the rest of the 6 cvs investigated but the extreme values of nectar production of cultivars overlapped in most cages.  


TEKNOSASTIK ◽  
2018 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Dina Amelia

There are two most inevitable issues on national literature, in this case Indonesian literature. First is the translation and the second is the standard of world literature. Can one speak for the other as a representative? Why is this representation matter? Does translation embody the voice of the represented? Without translation Indonesian literature cannot gain its recognition in world literature, yet, translation conveys the voice of other. In the case of production, publication, or distribution of Indonesian Literature to the world, translation works can be very beneficial. The position of Indonesian literature is as a part of world literature. The concept that the Western world should be the one who represent the subaltern can be overcome as long as the subaltern performs as the active speaker. If the subaltern remains silent then it means it allows the “representation” by the Western.


2016 ◽  
Vol 13 (1) ◽  
pp. 7-26
Author(s):  
Glenn Odom

With the rise of the American world literature movement, questions surrounding the politics of comparative practice have become an object of critical attention. Taking China, Japan and the West as examples, the substantially different ideas of what comparison ought to do – as exhibited in comparative literary and cultural studies in each location – point to three distinct notions of the possible interactions between a given nation and the rest of the world. These contrasting ideas can be used to reread political debates over concrete juridical matters, thereby highlighting possible resolutions. This work follows the calls of Ming Xie and David Damrosch for a contextualization of different comparative practices around the globe.


CounterText ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 30-56 ◽  
Author(s):  
Simona Sawhney

Engaging some of the questions opened by Ranjan Ghosh's and J. Hillis Miller's book Thinking Literature Across Continents (2016), this essay begins by returning to Aijaz Ahmad's earlier invocation of World Literature as a project that, like the proletariat itself, must stand in an antithetical relation to the capitalism that produced it. It asks: is there an essential link between a certain idea of literature and a figure of the world? If we try to broach this link through Derrida's enigmatic and repeated reflections on the secret – a secret ‘shared’ by both literature and democracy – how would we grasp Derrida's insistence on the ‘Latinity’ of literature? The groundlessness of reading that we confront most vividly in our encounter with fictional texts is both intensified, and in a way, clarified, by new readings and questions posed by the emergence of new reading publics. The essay contends that rather than being taught as representatives of national literatures, literary texts in ‘World Literature’ courses should be read as sites where serious historical and political debates are staged – debates which, while being local, are the bearers of universal significance. Such readings can only take place if World Literature strengthens its connections with the disciplines Miller calls, in the book, Social Studies. Paying particular attention to the Hindi writer Premchand's last story ‘Kafan’, and a brief section from the Sanskrit text the Natyashastra, it argues that struggles over representation, over the staging of minoritised figures, are integral to fiction and precede the thinking of modern democracy.


GYNECOLOGY ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 84-86
Author(s):  
Sergei P. Sinchikhin ◽  
Sarkis G. Magakyan ◽  
Oganes G. Magakyan

Relevance.A neoplasm originated from the myelonic sheath of the nerve trunk is called neurinoma or neurilemmoma, neurinoma, schwannoglioma, schwannoma. This tumor can cause compression and dysfunction of adjacent tissues and organs. The most common are the auditory nerve neurinomas (1 case per 100 000 population per year), the brain and spinal cord neurinomas are rare. In the world literature, there is no information on the occurrences of this tumor in the pelvic region. Description.Presented below is a clinical observation of a 30-year-old patient who was scheduled for myomectomy. During laparoscopy, an unusual tumor of the small pelvis was found and radically removed. A morphological study allowed to identify the remote neoplasm as a neuroma. Conclusion.The presented practical case shows that any tumor can hide under a clinical mask of another disease. The qualification of the doctor performing laparoscopic myomectomy should be sufficient to carry out, if necessary, another surgical volume.


Author(s):  
Pooja Sharma ◽  
Karan Veer

: It was 11 March 2020 when the World Health Organization (WHO) declared the name COVID-19 for coronavirus disease and also described it as a pandemic. Till that day 118,000 cases were confirmed of pneumonia with breathing problem throughout the world. At the start of New Year when COVID-19 came into knowledge a few days later, the gene sequencing of the virus was revealed. Today the number of confirmed cases is scary, i.e. 9,472,473 in the whole world and 484,236 deaths have been recorded by WHO till 26 June 2020. WHO's global risk assessment is very high [1]. The report is enlightening the lessons learned by India from the highly affected countries.


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