Meiotic restitution mechanisms and 2n pollen formation in a Solanum tuberosum dihaploid and in dihaploid x wild species hybrids*

1996 ◽  
Vol 115 (3) ◽  
pp. 157-161 ◽  
Author(s):  
C. Conicella ◽  
G. Genualdo ◽  
A. Errico ◽  
L. Frusciante ◽  
L. M. Monti
2007 ◽  
Vol 55 (3) ◽  
pp. 471-477 ◽  
Author(s):  
Elsa Lucila Camadro ◽  
Sandra Karina Saffarano ◽  
Juan Carlos Espinillo ◽  
Mateo Castro ◽  
Phillip W. Simon

1985 ◽  
Vol 62 (9) ◽  
pp. 479-487 ◽  
Author(s):  
Shelley A. Hermundstad ◽  
S. J. Peloquin

1988 ◽  
Vol 31 (4) ◽  
pp. 581-589 ◽  
Author(s):  
G. L. Yerk ◽  
S. J. Peloquin

1995 ◽  
Vol 75 (3) ◽  
pp. 675-678 ◽  
Author(s):  
Hala Nagib Nassar ◽  
Nagib M. A. Nassar ◽  
Clibas Vieira ◽  
Luiz S. Saraiva

An interspecific hybrid between cassava, Manihot esculenta Crantz, and M. neusana Nassar and the backcrossed progenies was examined meiotically and mitotically. The F1 hybrid showed irregular meiosis due to unpaired chromosomes. The backcrossed progeny ranged in fertility from 17.7 to 35.8%. Meiotic restitution was also observed in all of the hybrids. Diploid pollen formation also occurred and ranged from 0.6 to 1.6%. Irregular meiosis among the F1 hybrid produced aneuploidy in backcrossed progeny. When the F1 hybrid was used as the maternal plant in backcrosses with cassava, this improved seed setting in the BC1 progenies, whereas the reciprocal backcross produced sterile progenies. Key words: Wild species, meiotic restitution, aneuploidy, diploid gamete


Euphytica ◽  
1996 ◽  
Vol 89 (2) ◽  
pp. 185-191 ◽  
Author(s):  
F�lix C. Serqu�n ◽  
Stanley J. Peloquin

Author(s):  
E.O. Shmelkova ◽  
M.A. Slugina ◽  
A.A. Meleshin ◽  
E.V. Romanova

Работа посвящена разработке и тестированию универсальных праймеров для ПЦР-амплификации полноразмерных генов-ортологов β-фруктофуранозидазы (кислой вакуолярной инвертазы) у видов и сортов картофеля (Solanum tuberosum). Крахмал – основной источник энергии и резервный углевод, накапливающийся в амилопластах клубней. Образовавшаяся в результате фотосинтеза молекула глюкозы при реакции с фруктозой образует сахарозу – основную транспортную форму углеводов в растении. В клубни сахароза доставляется по флоэме (апопластный путь), где в межклеточном пространстве расщепляется до глюкозы и фруктозы, которые затем проникают в клетки паренхимы. Глюкоза служит в дальнейшем субстратом для синтеза крахмала в амилопластах. Однако при воздействии пониженных температур крахмал в клубнях картофеля разрушается до редуцирующих сахаров. Параллельно этому процессу идет ресинтез сахарозы до глюкозы и фруктозы за счет фермента кислой вакуолярной инвертазы (β-фруктофуранозидазы), кодируемой геном Pain-1. В совокупности эти процессы приводят к избыточному накоплению моносахаров в клубнях картофеля, так называемому холодовому осахариванию (cold-induced sweetening). При этом создаются условия для интенсивного образования меланоидинов, вызывающих потемнение мякоти картофеля, что значительно ухудшает товарное качество продукта. Таким образом, изучение гена Pain-1, кодирующего вакуолярную инвертазу, а именно, его идентификация и анализ структуры – важная задача, необходимая для поиска доноров, устойчивых к холодовому осахариванию. Первоочередная задача для этого – разработка и тестирование праймерных комбинаций, позволяющих амплифицировать полноразмерный ген у диких видов картофеля, а также сортов и линий культивируемого картофеля (S. tuberosum). В данной работе приведены результаты разработки и тестирования универсальных праймеров, с помощью которых можно амплифицировать как полноразмерные гены-ортологи, так и фрагменты гена Pain-1, а также подобраны оптимальные условия для проведения ПЦР реакции. Было разработано 6 праймерных комбинаций (PainF – PainR, PainF – Pain1exR, Pain1exF – Pain3exR, Pain2inF – Pain2inR, Pain3exF – Pain5exR, Pain5exF – PainR), среди которых комбинация PainF – PainR позволяла амплифицировать полноразмерный ген, остальные – внутренние и будут использованы в дальнейшем при секвенировании фрагментов исследуемого гена. Эти праймеры были успешно протестированы на 15 образцах, включающих представителей пяти дикорастущих видов картофеля (S. gourlay, S. chacoense, S. pinnatissectum, S. stoloniferum, S. vernei) и десяти сортов российской и зарубежной селекции (Гала, Ласунок, Ред Скарлетт, Рассет Бербанк, Мирас, Башкирский, Жуковский ранний, Матушка, Елизавета, Сударыня).The purpose of research is design and testing of universal primers for PCR amplification of full-length-fructofuranozidase orthologs genes (acid vacuolar invertase) in wild species and potato (Solanum tuberosum) varieties. Starch is the main source of energy and a reserve carbohydrate, that accumulates in tubers amyloplasts. Glucose molecule, produced by photosynthesis, reacts with fructose and forms sucrose, which is the main transport type of carbohydrates in the plant. In the tuber, sucrose is delivered via phloem (apoplast), where it splits into glucose and fructose, which then go to the parenchyma cells. Glucose is a further substrate for the starch synthesis in amyloplasts. However, low temperatures influence on potato tubers leads to starch break down to reducing sugars. In parallel to this process there is happens resynthesis of sucrose to glucose and fructose by acid vacuolar invertase enzyme (β-fructofuranosidase) encoded by Pain-1 gene. Together, these processes lead to an excessive accumulation of monosaccharides in potato tubers. This process also called as cold-induced sweetening. It creates conditions for the intensive formation of melanoidins, which cause a potato tubers darkening, which considerably impairs the commercial quality of the product. Thus, the study Pain-1 gene that encodes the vacuolar invertase (its identification and structure analysis) is an important task required for the search of donors resistant to cold-induced sweetening. The primary task for this is the design and testing of primer combinations that allow to amplify the full-length gene in wild potato species, varieties and lines of cultivated potato. In this work, we develop and test universal primers, that can amplify both full-length orthologs and fragments of the Pain-1 gene, and also select the optimal conditions for carrying out the PCR reaction. Summary. The purpose of research is design and testing of universal primers for PCR amplification of full-length-fructofuranozidase orthologs genes (acid vacuolar invertase) in wild species and potato (Solanum tuberosum) varieties. Starch is the main source of energy and a reserve carbohydrate, that accumulates in tubers amyloplasts. Glucose molecule, produced by photosynthesis, reacts with fructose and forms sucrose, which is the main transport type of carbohydrates in the plant. In the tuber, sucrose is delivered via phloem (apoplast), where it splits into glucose and fructose, which then go to the parenchyma cells. Glucose is a further substrate for the starch synthesis in amyloplasts. However, low temperatures influence on potato tubers leads to starch break down to reducing sugars. In parallel to this process there is happens resynthesis of sucrose to glucose and fructose by acid vacuolar invertase enzyme (β-fructofuranosidase) encoded by Pain-1 gene. Together, these processes lead to an excessive accumulation of monosaccharides in potato tubers. This process also called as cold-induced sweetening. It creates conditions for the intensive formation of melanoidins, which cause a potato tubers darkening, which considerably impairs the commercial quality of the product. Thus, the study Pain-1 gene that encodes the vacuolar invertase (its identification and structure analysis) is an important task required for the search of donors resistant to cold-induced sweetening. The primary task for this is the design and testing of primer combinations that allow to amplify the full-length gene in wild potato species, varieties and lines of cultivated potato. In this work, we develop and test universal primers, that can amplify both full-length orthologs and fragments of the Pain-1 gene, and also select the optimal conditions for carrying out the PCR reaction. In total 6 primer combinations were designed (PainF - PainR, PainF - Pain1exR, Pain1exF - Pain3exR, Pain2inF - Pain2inR, Pain3exF - Pain5exR, Pain5exF - PainR), where PainF - PainR primer combination allowed to amplify a full-sized gene, the rest are internal and will be used in the further fragments sequencing of the β-fructofuranosidase gene. These primers were successfully tested on 15 samples, including five wild species of potato (S. gourlay, S. chacoense, S. pinnatissectum, S. stoloniferum, S. vernei) and ten varieties of Russian and foreign breeding (Gala, Lasunok, Red Scarlet , Rasset Burbank, Miras, Bashkirsky, Zhukovsky ranniy, Matushka, Elizaveta, Sudaryna).


Genome ◽  
1991 ◽  
Vol 34 (3) ◽  
pp. 413-420 ◽  
Author(s):  
Fouzia Bani-Aameur ◽  
F. I. Lauer ◽  
R. E. Veilleux ◽  
A. Hilali

Tetraploid potato hybrids representing three genomic compositions (TTTT, TTPP, and TTPC (T, Solanum tuberosum; P, Solanum phureja; C, Solanum chacoense)) were constructed by crossing S. tuberosum (2n = 4x = 48) cultivars or advanced breeding selections among themselves or with 2n pollen producing selections of either S. phureja (2n = 2x = 24) or F1 hybrids between S. phureja and S. chacoense (2n = 2x = 24). Seedling families were evaluated in the fall season and selections within each family were evaluated in spring trials at Ait-Melloul, Morocco. Genomic composition was the greatest source of variance for yield-attributing traits, with TTPC outperforming other hybrids in fall trials for vine vigor, tuber set, and tuber yield and TTPP outperforming other hybrids in spring trials for the same traits. The results imply that analytic breeding for potato by construction of complex interspecific hybrids may result in clones surpassing a previously proposed heterotic threshold if the target environment is conducive to expression of favorable traits from alien germ plasm.Key words: Solanum phureja, Solanum chacoense, Solanum tuberosum, 4x–2x hybrids, potato, analytic breeding.


1979 ◽  
Vol 21 (4) ◽  
pp. 525-530 ◽  
Author(s):  
Nicholi Vorsa ◽  
E. T. Bingham

Four diploid (2x) clones of alfalfa, Medicago sativa L., which produced good seed set when used as male parents in 4x-2x crosses were selected for study. The 2x clones descended from 2x haploids of cultivated 4x alfalfa. Fertility in the 4x-2x cross was due to the production of pollen with the unreduced chromosome number (2n pollen) from the 2x parent. The cytological mechanism of 2n pollen formation was found to be disorientation of spindles at metaphase II in up to 38% of the pollen mother cells. Thus, both n and 2n pollen were produced by all four diploids examined. Normal spindles at metaphase II were oriented such that they defined the poles of a tetrahedron and resulted in normal tetrads in a tetrahedral arrangement. Disoriented spindles were basically parallel to each other and resulted in formation of dyads and occasionally a triad. Dyads developed into two 2n pollen grains; triads developed into one 2n and two n pollen grains. Since both n and 2n pollen grains are produced by the diploids, they can be maintained as diploids or they can be used as male parents in crosses to tetraploids. The genetic constitution of 2n pollen resulting from parallel spindles is similar to that expected after first division restitution of meiosis and much of the heterozygosity of the diploid parent is conserved in the gametes. The 2n gamete mechanism has potential application in germplasm transfer and in maximizing heterozygosity in tetraploid hybrids.


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