scholarly journals Reproductive ability of black currant cultivars after pollen cryopreservation in liquid nitrogen

2021 ◽  
Vol 182 (4) ◽  
pp. 71-78
Author(s):  
O. A. Tikhonova ◽  
E. A. Radchenko ◽  
A. V. Pavlov

Background. Studying the reproductive ability of black currant cultivars after long-term cryopreservation of their pollen in liquid nitrogen is very important for plant diversity conservation and for the effectiveness of breeding efforts.Materials and methods. Five black currant cultivars served as the material for the research. The viability of black currant pollen after cryopreservation in liquid nitrogen was analyzed. Pollen viability was tested on an artificial medium containing 10% of sucrose and 0.8% of agar. The viability of pollen was tested on the black currant collection at Pushkin and Pavlovsk Laboratories of VIR. The cultivar ‘Andreevskaya’ (k-15630) was pollinated with pollen stored for one year in liquid nitrogen (–196°C) as well as with fresh pollen (control test).Results and conclusion. After 12 months of conservation under ultralow temperatures there was a change in the level of pollen viability depending on the genotype: it varied from 10.4% (cv. ‘Pozdnyaya poslevoennaya’, k-7654) to 50.4% (cv. ‘Kriviai’, k-42517), while its mean value was 0.9% higher than the mean initial viability. The fruit setting rate in the control option was 81.3–94.2%. When pollinated with pollen kept in liquid nitrogen for one year, the fruit setting rate varied from 69.2% (‘Kacha’, k-44185) to 93.3% (‘Belorusochka’, k-41978); the remaining cultivars (‘Pozdnyaya poslevoennaya’; ‘Chereshneva’, k-42481; and ‘Kriviai’) demonstrated intermediate values of this indicator, i.e., the reproductive ability of pollen after cryopreservation was high even despite its low viability. As for the fruit weight, no differences were shown by cvs. ‘Kacha’, ‘Chereshneva’ and ‘Kriviai’ in both pollination options, while this indicator in cvs. ‘Belorusochka’ and ‘Pozdnyaya poslevoennaya’ was lower than the control by 0.31 and 0.24 g, respectively.

2020 ◽  
pp. 713-723
Author(s):  
Abdelazize ElJiati

As many studies on other crops showed an acropetal decline of fruit-set and fruit size in the inflorescence, this paper investigates the effect of flower position in spikelets in the ‘Sukkary’ variety of date palm on fruit-set and final fruit weight. Also studied was the best time to apply strand-cut (bunch cut) as an alternative to hand thinning, to increase final fruit weight. Hand thinning is a labor cost operation and worker productivity operation is one adult tree per day maximum. To study fruit-set in relation to fruit position, three types of pollen were used to pollinate female trees: new pollen harvested in March 2018, pollen stored for one year at room temperature (25-35° C), and pollen stored for two years at room temperature. Four weeks after pollination, fruits aborted and those non-aborted in every bunch were counted. Recording was done in every spikelet from proximal to distal. To study the effect of fruit position in spikelet on fruit weight, fresh pollen was used to pollinate ‘Sukkary’ females. Every two days, fruit weight was measured from pollination to harvest, and fruit growth pattern was drawn. An analysis of variance (ANOVA) was carried out for the final fruit weight in every spikelet part. This investigation showed no pattern in fruit-set or in final fruit weight when using new pollen. When pollinated with old pollen that was one and two years old, the proximal ‘Sukkary’ flowers of the spikelets showed less fruit-set compared to those of the middle and distal part. This basipetal decline is explained by low viability of old pollen, combined with the basipetal opening of the spathes in date palm...


Author(s):  
A. B. Gorbunov ◽  
T. V. Kurlovich ◽  
T. I. Snakina ◽  
T. A. Nedovesova

Creation of allotetraploid cowberry-blueberry hybrids is a promising direction in Vacciniaceae breeding. However, obtaining such hybrids is difficult because of biological features of tetraploid cowberry. In this regard the aim of research was study of pollen viability of tetraploid cowberry, its crossing ability with different species and interspesific blueberry hybrid in various years, as well as based on the results obtained, selection of promising methods of growth stimulation of pollen tubes, hybrid seed setting and cultivation of hybrid seedlings.As a result of research it has been established that tetraploid cowberry is characterized by low productivity and pollen viability, although its viability may reach 10.7 % in some years. Hybrid seedlings gradually died off with growth. On the base of the data obtained it is proposed that a special technique be used to increase hybrid fruit setting (pollination of flowers by a mixture of pollen, pollination in different life spans of a flower, castration of flowers without removing a corolla, reciprocal crosses, spraying pollinated flowers by solutions of growth regulators and microelements) and cultivation of hybrid seedlings (in vitro culture).


2020 ◽  
Vol 181 (3) ◽  
pp. 110-119
Author(s):  
O. A. Tikhonova ◽  
O. A. Gavrilova ◽  
E. A. Radchenko ◽  
V. G. Verzhuk ◽  
A. V. Pavlov

Background. Learning about morphological and biological features of pollen is very important to make correct estimations of plant productivity and breeding efficiency.Materials and methods. The viability of black currant pollen was analyzed in 2019 at the Laboratory for Long-Term Storage of Plant Genetic Resources, N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). Eleven black currant cultivars of various ecogeographic and genetic origin maintained at Pushkin and Pavlovsk Laboratories of VIR served as the material for the research. Pollen viability was tested on an artificial medium with 10% sucrose and 0.8% agar. Morphological studies were carried out using light and confocal laser scanning microscopy at the Palynology Laboratory and the Core Centrum of Cell and Molecular Technologies in Plant Science housed by the Komarov Botanical Institute (BIN).Results and conclusion. The prevailing adverse weather conditions in 2019 produced a negative impact on the process of male generative structure formation. The level of pollen viability, depending on the cultivar, ranged from 17.98 to 58.60%. After exposure to liquid nitrogen (–196°C) for 6 months, the number of germinated pollen grains increased 1.1 to 3.2 times in all the studied cultivars, except one (‘Pozdnyaya poslevoennaya’, k-7652). A palynomorphological study revealed that reduced pollen viability in some cultivars (‘Krasnoyarskaya 1018’, k-7607; ‘Tsema’, k-25900; ‘Pozdnyaya poslevoennaya’, k-7652) was associated with morphological deviations in the sporoderm structure (small pollen grains, exine thickening and formation of verrucate mesoporium surfaces). A low positive correlation was observed between the level of pollen viability and the diameters of the pore (r = 0.43) and pollen grain (r = 0.27). An insignificant negative correlation was apparent between the level of viability and the exine thickness (r = –0.33). 


1970 ◽  
Vol 11 ◽  
pp. 47-50
Author(s):  
Tul Bahadur Poon ◽  
TM Rao ◽  
C Aswath ◽  
PE Rajasekharan ◽  
DP Kumar

Fresh pollen of 16 promising genotypes of gladiolus was tested for their pollen viability. Modified cellophane method was employed to assess the pollen viability. Pollen germination media consisted of 15% sucrose supplemented with 300 ppm calcium nitrate, 200 ppm magnesium sulphate, 100 ppm potassium nitrate and 100 ppm boric acid. Highly significant variations were observed for percentage of pollen germination, non-germinated pollen and sterile pollen. The highest pollen germination (76.41%) was in genotype Hybrid selection 88-10-22, and did not differ significantly from Gladiolus callianthus (75.41%), Sapna (75.10 %), Hybrid selection 86-32-11, (73.28 %), Kum Kum (69.41%), Poonam (69.22 %), Hybrid selection 87-22-1 (67.87 %), Hybrid selection 87-1-1 (67.61 %), Psittacinus hybrid (64.64%) and Darshan (63.97%). The lowest non- germinated pollen (10.47%) was in genotype Gladiolus callianthus, and insignificantly followed by Hybrid selection 88-10-22 with 18.77 % and Hybrid selection 87-22-1 with 18.95 %. The lowest percentage of sterile pollen was noticed in genotype Sapna (2.82%) followed by Poonam with 4.00 % Hybrid selection 88-10-22 with 4.82% and Hybrid selection 82-11-27 with 5.22%. Key words: Gladiolus; germination; pollen DOI: 10.3126/njst.v11i0.4089Nepal Journal of Science and Technology 11 (2010) 47-50


2012 ◽  
Vol 64 (2) ◽  
pp. 63-68 ◽  
Author(s):  
Stanisław Wociór ◽  
Irena Wójcik ◽  
Salwina Palonka

The present study, carried out in the period 2007-2009 in the Sandomierz Upland, did not show a significant effect of foliar fertilization on trunk thickness and canopy volume in the cultivar Łutówka. However, under the influence of urea applied three times in combination with Florovit at a concentration of 0.5%, a clear increasing trend was observed in the above mentioned parameters used to assess the strength of growth. In years of abundant fruiting, this study showed a significant increase, or on the verge of significance, in yield after threefold application of urea and Florovit in combination. A small insignificant effect of fertilization on fruit weight shows that the growth in yield after the application of fertilization was produced as a consequential effect of a significant increase in the length of one-year shoots and thereby in flowering intensity of the 'Łutówka' cherry trees. In the case of the sour cherry cultivar Łutówka bearing fruit on one-year shoots, foliar feeding after flowering using multi-nutrient fertilizers and urea can be recommended as a technological treatment, in particular in years of abundant fruiting.


2021 ◽  
Author(s):  
Jaroslav Chum ◽  
Kateřina Podolska ◽  
Jiri Base ◽  
Jan Rusz

<p>     Characteristics of gravity waves (GWs) are studied from multi-point and multi-frequency continuous Doppler sounding in the Czech Republic. Three dimensional (3D) phase velocities of GWs are determined from phase shifts between the signals reflecting from the ionosphere at different locations that are separated both vertically and horizontally; the reflection heights are determined by a nearby ionospheric sounder located in Průhonice. Wind-rest frame (intrinsic) velocities are calculated by subtracting the neutral wind velocities, obtained by HWM-14 wind model, from the observed GW velocities. In addition, attenuation of GWs with height was estimated from the amplitudes (Doppler shifts) observed at different altitudes. A statistical analysis was performed over two one-year periods: a) from July 2014 to June 2015 representing solar maximum b) from September 2018 to August 2019 representing solar minimum.   </p><p>     The results show that the distribution of elevation angles of wave vectors in the wind–rest frame is significantly narrower than in the Earth frame (observed elevations). Possible differences were also found between the wind–rest frame elevation angles obtained for the solar maximum (mean value (around -24°) and solar minimum (mean value round -37°). However, it is demonstrated that the elevation angles partly depended on the daytime and day of year. As the distribution of the time intervals suitable for the 3D analysis in the daytime–day of year plane was partly different for solar maximum and minimum, no reliable conclusion about the possible dependence of elevation angles on the solar activity can be drawn.</p><p>     It is shown that the attenuation of GWs in the ionosphere was in average smaller at the lower heights. This is consistent with the idea that mainly viscous damping and losses due to thermal conductivity are responsible for the attenuation.</p><p>  </p>


PEDIATRICS ◽  
1964 ◽  
Vol 33 (4) ◽  
pp. 507-511
Author(s):  
Yehuda Matoth ◽  
Ariela Pinkas ◽  
Rina Zamir ◽  
Fouad Mooallem ◽  
Nathan Grossowicz

The level of folic and folinic acid in whole blood was assayed in 373 healthy infants from birth to one year. Folic acid was high at birth and dropped gradually over the first 8 postnatal weeks. The mean value for the remainder of the first year was significantly below the adult mean. Folinic acid was likewise high at birth and dropped parallel with the folic acid. However, following the initial drop, folinic acid mean values remained well above the adult mean. Folic and folinic acid values were higher in breast-fed than in artificially fed infants and lower in infants whose economic status was poor than in babies belonging to families of higher income.


Viruses ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 144 ◽  
Author(s):  
Miguel F Varela ◽  
Enrique Rivadulla ◽  
Alberto Lema ◽  
Jesús L Romalde

Viral agents of human gastroenteritis affect people of all ages across the globe. As a mainly self-limiting disease, it is difficult to evaluate the real prevalence of etiological agents circulating in each region. Many of the analyzed outbreaks are caused by viruses of the family Caliciviridae, especially the genus Norovirus (NoV). Most studies have focused on other enteric viruses, leaving sapovirus (SaV) underestimated as an important emerging human threat. This one-year study analyzed clinical samples from hospital outpatients with acute gastroenteritis in Spain, with the aim of revealing the importance of human SaV as an emerging viral pathogen. A total of 2667 stools were tested using reverse transcription (RT)-qPCR to detect and quantify SaV. Sapovirus was detected in all age groups, especially in infants, children, and the elderly. The prevalence was 15.64% (417/2667), and was slightly higher in 0–2- and 3–5-year-olds (19.53% and 17.95%, respectively) and much lower in 13–18-year-olds (9.86%). Positive samples were detected throughout the year, with peaks of detection during autumn and the late winter to early spring months. The mean value for the quantified samples was 6.5 × 105 genome copies per gram of stool (GC/g) (range 2.4 × 103–6.6 × 1011 GC/g). RT-nested PCR and sequencing were used for further genotyping. Genetic characterization showed a predominance of genogroup I (GI), followed by GII and GIV. The detection of multiple genotypes suggests the circulation of different strains without any clear tendency. The results obtained suggest SaV as the second major gastroenteritis agent after NoV in the region.


Horticulturae ◽  
2020 ◽  
Vol 6 (3) ◽  
pp. 41 ◽  
Author(s):  
Mary Sutton ◽  
John Doyle ◽  
Dario Chavez ◽  
Anish Malladi

Fruit size is a highly valued commercial trait in peach. Competition among fruit and among other sinks on a tree reduces potential growth rate of the fruit. Hence, crop-load management strategies such as thinning (removal of flowers or fruit) are often practiced by growers to optimize fruit size. Thinning can be performed at bloom or during early fruit development and at different intensities to optimize fruit growth responses. Responses to thinning may be cultivar and location specific. The objective of the current study was to fine-tune thinning strategies in the southeastern United States, a major peach producing region. Timing and intensity of thinning were evaluated across multiple cultivars over three years. Thinning at bloom or at 21 d after full bloom (DAFB) improved fruit size in comparison to unthinned trees in ‘Cary Mac’ and ‘July Prince’, respectively, in one year. Bloom-thinning reduced fruit yield (kg per tree) in the above cultivars in one year, suggesting that flower thinning alone may not be a viable option in this region. Intensity of thinning, evaluated as spacings of 15 cm and 20 cm between fruit, did not differentially affect fruit weight or yield. However, fruit diameter decreased quadratically with increasing fruit number per tree in ‘Cary Mac’, ‘July Prince’ and ‘Summer Flame’. Similarly, fruit weight decreased quadratically in response to increase in fruit number per tree in ‘Cary Mac’ and ‘July Prince’. Further, yield-per-tree decreased with increasing fruit size in ‘Cary Mac’ and ‘July Prince’. Importantly, these relationships were cultivar specific. Together, the data suggest that achieving a target fruit number per tree is an effective strategy for crop-load management to optimize fruit size in southeastern peach production. The target fruit number per tree may potentially be achieved through a combination of flower and fruit-thinning during early fruit development. Such an approach may provide flexibility in crop-load management in relation to adverse weather events.


2011 ◽  
Vol 30 (No. 3) ◽  
pp. 90-97 ◽  
Author(s):  
Z. Vachůn

Weight, height, width and diameter of fruits and stones were evaluated in 21 apricot cultivars and hybrids in 1994&ndash;1997. Statistically significant differences between the measured values of traits confirmed their applicability for objective characterization of genotypes. The evaluated traits are genetic dispositions. It was also proved by the rank of genotypes arranged according to the values of particular traits in one year that was highly significantly identical in the other years of the evaluated period (correlation coefficient r = 0.45<sup>++</sup> to 0.87<sup>++</sup>). The relationship between fruit weight and other traits (stone weight, stone height and stone width) is not linear. Fruit weight increases (or decreases) faster towards the limit values of traits. The average percentage proportion of stone weight in fruit weight ranged from 4.9% to 9.6% in the genotypes over the period of four years. A lower proportion of stone in fruit weight is a positive trait for selection of suitable genotypes for direct consumption and flesh processing. This trait can also be a suitable criterion of genotype selection to breed cultivars with a low proportion of inedible part. Promising cultivar Lemeda is an example of the low stone proportion in flesh weight. A high level of variability was found in the values of stone and fruit weight (coefficient of variation v = 19.00% and v = 24.74%, respectively). Coefficients of variation for other traits (fruit and stone height, width and diameter) were by more than a half lower. &nbsp;


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