Interspecific hybrids between Medicago sativa L. and annual Medicago containing Alfafa weevil resistance

2005 ◽  
Vol 84 (1) ◽  
pp. 80-89 ◽  
Author(s):  
Yuko Mizukami ◽  
Mitsuru kato ◽  
Tadashi Takamizo ◽  
Michio Kanbe ◽  
Susumu Inami ◽  
...  
Keyword(s):  
Medicago Sativa ◽  
Interspecific Hybrids ◽  
Medicago Sativa L ◽  
Annual Medicago

A potential solution to the chromosome instability problem in hexaploid alfalfa, Medicago sativa L.

Genome ◽  
1989 ◽  
Vol 32 (2) ◽  
pp. 302-306 ◽  
Author(s):  
T. J. McCoy
Keyword(s):  
Medicago Sativa ◽  
Interspecific Hybrids ◽  
Chromosome Instability ◽  
Chromosome Stability ◽  
Potential Solution ◽  
Chromosome Counts ◽  
Instability Problem ◽  
Commercial Use ◽  
Medicago Sativa L ◽  
The Cross

Autohexaploid alfalfa (2n = 6x = 48) is chromosomally unstable, which prevents commercial use. The objective of this investigation was to test whether synthesizing Medicago hexaploids (2n = 6x = 48) that are alloautohexaploids results in chromosomally stable hexaploid populations. Previous research in our laboratory demonstrated a lack of affinity between the genomes of alfalfa and M. papillosa Boiss. Triploid (2n = 3x = 24) interspecific hybrids with two M. papillosa genomes and one genome of M. sativa were readily recovered from seed following the cross (2x) M. sativa × (4x) M. papillosa. For this study, the triploids were chromosomally doubled to produce alloautohexaploids, and these alloautohexaploids were used to test chromosome stability in hexaploids with no more than four homologous genomes. Chromosome counts of 47 progeny from intercrossing the alloautohexaploids demonstrated all were hexaploid, indicating chromosome stability. Designing novel genomic combinations based on genomic affinity may result in higher yielding alfalfa populations that have a modified cytogenetic structure.Key words: Medicago cancellata, Medicago papillosa, Medicago saxatilis, genomic affinity, hexaploids.

Allotetraploid behavior of hybrids of Medicago sativa L. and M. papillosa Boiss.

Genome ◽  
1989 ◽  
Vol 32 (1) ◽  
pp. 6-11 ◽  
Author(s):  
T. J. McCoy ◽  
G. L. Quarisa
Keyword(s):  
Medicago Sativa ◽  
Pollen Mother Cell ◽  
Embryo Culture ◽  
Mother Cell ◽  
Cytogenetic Analysis ◽  
Interspecific Hybrids ◽  
Backcross Progeny ◽  
Male Sterile ◽  
Genomic Constitution ◽  
Medicago Sativa L

Diploid (2n = 2x = 16), triploid (2n = 3x = 24), and tetraploid (2n = 4x = 32) interspecific hybrids between alfalfa (Medicago sativa L.) and M. papillosa Boiss. were recovered either from seed (the triploid hybrids) or from ovule–embryo culture (the diploid and tetraploid hybrids). Cytogenetic analysis of diploid interspecific hybrids (with one genome of M. sativa, designated S, and one genome of M. papillosa, designated P), indicated significant genomic affinity, with an average of 7.6 bivalents and 0.8 univalents per pollen mother cell. In contrast, cytogenetic analysis of the triploid interspecific hybrids (with one S genome and two P genomes) indicated little if any genomic affinity between M. sativa and M. papillosa. In 7 of 14 triploid hybrids analyzed no trivalent configurations were observed, and in the other hybrids, trivalent frequency ranged from 0.1 to 0.4 per pollen mother cell. Tetraploid interspecific hybrids with two S and two P genomes had predominantly bivalent pairing. Based on the lack of homology of S and P genomes, the tetraploid hybrids are basically allotetraploids (SSPP). Therefore, backcross progeny from crossing the tetraploid hybrids with tetraploid M. sativa have the genomic constitution SSSP. Univalents and trivalents were observed in first backcross (BC1) progeny, as expected, based on an allotetraploid interpretation. Most of the BC1 progeny were partially or completely male sterile, and female fertility was significantly reduced. Potential uses of homoeologous genomes such as M. papillosa in alfalfa genetic and breeding studies are discussed.Key words: cytogenetics, interspecific hybrids, ovule –embryo culture.

Interspecific hybridization of Medicago sativa L. and M. rupestris M. B. using ovule–embryo culture

1985 ◽  
Vol 27 (2) ◽  
pp. 238-245 ◽  
Author(s):  
T. J. McCoy
Keyword(s):  
Medicago Sativa ◽  
Embryo Culture ◽  
Interspecific Hybrid ◽  
Interspecific Hybrids ◽  
Embryo Rescue ◽  
Culture Method ◽  
Hybrid Plants ◽  
Successful Recovery ◽  
Hybrid Embryo ◽  
Medicago Sativa L

An ovule–embryo culture method was used to produce the first interspecific hybrids between alfalfa (Medicago sativa L.) and Medicago rupestris M. B. Culture of fertilized ovules from the cross diploid (2n = 2x = 16) M. sativa (jpjp) × diploid (2n = 2x = 16) M. rupestris began 14 days after pollination. After 5 days in culture, the interspecific hybrid embryo was removed and transferred to fresh medium, where development into a plant occurred. Forty-six M. sativa – M. rupestris F1 hybrids have been recovered using this technique. All but one of the 46 F1 hybrids were diploid (2n = 2x = 16); the only exception was tetraploid (2n = 4x = 32). The most frequent meiotic configurations observed in the F1 hybrid plants were eight bivalents or seven bivalents and two univalents, indicating significant homology between M. sativa and M. rupestris genomes. However, pollen stainability (0–12%) and pollen germination (0–6%) were extremely low. Similar to the production of the F1, no first backcross (BC1) plants were obtained from seed; however, the ovule–embryo culture method was found to be a very effective method for recovering BC1 plants and hundreds of BC1 plants have been produced. The BC1 plants from crossing the F1 with diploid M. sativa were predominantly diploid. Medicago rupestris can now be considered a potential germplasm source for alfalfa improvement. The ovule–embryo culture method represents the first successful recovery of Medicago interspecific hybrids via some form of embryo rescue. Importantly, it appears this technique can be applied to other interspecific hybrid combinations in the Medicago genus.Key words: Medicago, alfalfa, embryo culture, interspecific hybrid.

Cytogenetic analysis of interspecific hybrids between alfalfa (Medicago sativa L.) and M. rhodopea Velen.

Genome ◽  
1987 ◽  
Vol 29 (6) ◽  
pp. 853-858 ◽  
Author(s):  
C. R. Denton ◽  
T. J. McCoy
Keyword(s):  
Medicago Sativa ◽  
Embryo Culture ◽  
Pollen Germination ◽  
Interspecific Hybrids ◽  
Backcross Progeny ◽  
Microspore Mother Cell ◽  
Triploid Hybrid ◽  
Pollen Stainability ◽  
Medicago Sativa L ◽  
High Level

Interspecific hybrids between diploid (2n = 2x = 16) Medicago sativa L. and diploid (2n = 2x = 16) M. rhodopea Velen., were recovered using an ovule–embryo culture methodology. Most hybrids were vigorous, and morphological comparisons demonstrated that F1 hybrids were generally intermediate between that of the parents. Peroxidase isozyme phenotypes of the F1 hybrids confirmed hybridity. The chromosome number of most of the hybrids was diploid (2n = 2x = 16), with the exceptions of two triploids (2n = 3x = 24) and two tetraploid (2n = 4x = 32) plants. Chromosome pairing configurations in diploids were almost exclusively eight bivalents or seven bivalents and two univalents, indicating a high level of homology between the M. sativa and M. rhodopea genomes. However, the one triploid hybrid analyzed had only 0.4 trivalents per microspore mother cell indicating preferential pairing of parental genomes. Pollen stainability, pollen germination, and fertility of the diploid F1 hybrid plants were very low; however, it was possible to obtain backcross progeny (BC1) from seed. Pollen stainability, pollen germination, and fertility of the BC1 plants were also very low; however, most BC1 plants had workable levels of male and female fertility. The utilization of M. rhodopea in studies of the evolution of hexaploid Medicago species is discussed. Key words: interspecific hybrids, ovule–embryo culture, isozymes, Medicago.

Uneven ploidy levels and a reproductive mutant required for interspecific hybridization of Medicago sativa L. × Medicago dzhawakhetica Bordz.

1984 ◽  
Vol 26 (5) ◽  
pp. 511-518 ◽  
Author(s):  
T. J. McCoy ◽  
L. Y. Smith
Keyword(s):  
Medicago Sativa ◽  
Interspecific Hybrids ◽  
Backcross Progeny ◽  
Male Sterile ◽  
Plant Variation ◽  
Ploidy Levels ◽  
Male And Female ◽  
Large Numbers ◽  
Medicago Sativa L ◽  
Efficient Recovery

Crossing diploid (2n = 2x = 16) Medicago sativa L. (homozygous for the gene, jp, that causes failure of the postmeiotic cytokinesis) and tetraploid (2n = 4x = 32) Medicago dzhawakhetica Bordz. resulted in efficient recovery of interspecific hybrids. Interspecific hybrids were produced in large numbers (1.15 – 5.60 hybrids per pollination), comparable to intraspecific same-ploidy level crosses within M. sativa. All 237 interspecific hybrids were triploid (2n = 3x = 24) or near triploid. Morphologically, the F1 hybrids were intermediate, although they tended to be more similar to the M. dzhawakhetica parent. Medicago dzhawakhetica was resistant to spring blackstem (caused by Phoma medicaginis Malb. and Roum.), whereas the M. sativa parents were susceptible. The F1 hybrids were also resistant to P. medicaginis. Chromosome pairing in the hybrids showed plant-to-plant variation; however, trivalent frequencies in some F1 hybrids were comparable to that observed in M. sativa triploids, indicating potential for recombination between M. sativa and M. dzhawakhetica genomes. Although the triploid hybrids were male sterile, and nearly female sterile, it was possible to produce backcross progeny. The first backcross was both male and female fertile.Key words: Medicago, hybridization, breeding, tetraploid, triploid, sterility.

Estimación de biomasa aérea de forrajes de invierno bajo riego a través de un dron

2019 ◽  
Vol 12 (4) ◽  
Author(s):  
Francisco Gavi Reyes ◽  
César Botello-Aguillón ◽  
Leonardo Tijerina-Chávez ◽  
Arturo Galvis-Spíndola ◽  
Rodrigo Roblero-Hidalgo
Keyword(s):  
Medicago Sativa ◽  
Avena Sativa ◽  
Medicago Sativa L

E Objetivo: Desarrollar un procedimiento para estimar biomasa con imágenes digitales captadas desde un dron y modelación 3D (ID-Dron-3D) aplicable en alfalfa (Medicago sativa L.) y avena forrajera (Avena sativa L.). Diseño/metodología/aproximación: Con una cámara digital acoplada al dron se obtuvieron imágenes antes de la cosecha de los cultivos, que fueron procesadas con software para luego estimar volumen de biomasa. En cada cultivo se midió altura de la planta y área cosechada, volumen aparente y real de biomasa, y peso de biomasa fresca y seca. Resultados: Con base en el análisis de regresión se obtuvieron modelos lineales a una p<0.05 para predecir: biomasa fresca en avena (R2=0.70) y alfalfa (R2 =0.47); y biomasa seca en avena (R2=0.78) y en alfalfa (R2=0.31) mediante ID-Dron-3D. Limitaciones del estudio/implicaciones: Considerando las R2 de los modelos obtenidos, los resultados en la avena forrajera fueron mejores, respecto a los detectados en alfalfa, lo cual se puede deber a la mayor variabilidad de la cobertura vegetal, ya que, en algunas unidades de muestreo, las plantas de alfalfa no cubrían completamente el suelo. Hallazgos/conclusiones: El rendimiento de biomasa fresca y seca de ambos cultivos se correlacionó significativamente con su respectivo volumen aparente estimado con imágenes digitales tomadas desde un dron y su procesamiento 3D (ID-Dron-3D).

ALFALFA (Medicago sativa L.) CULTIVADA EN CAMPECHE, MÉXICO Y SU INTEGRACIÓN LOCAL EN LA ALIMENTACIÓN DE CORDEROS EN CONFINAMIENTO

2018 ◽  
Vol 11 (9) ◽  
Author(s):  
CC. Castillo-Águilar
Keyword(s):  
Medicago Sativa ◽  
Pennisetum Purpureum ◽  
Medicago Sativa L

Se comparó el uso de diferentes dietas con base en heno de alfalfa cultivada (Medicago sativa L.) en Campeche y su relación con un concentrado comercial y pasto Taiwán (Pennisetum purpureum), T1=concentrado comercial, T2=T1+heno de alfalfa, T3=T1+pasto Taiwán, T4=heno de alfalfa. Se evaluó el comportamiento productivo y metabólico de corderos en sistema intensivo utilizando 20 corderos machos con encaste de Pelibuey, Dorper y Black Belly de 12.5±1 kg de peso vivo (PV). Se midió el consumo de materia seca total (CMS), la ganancia diaria de peso (GDP), la conversión alimenticia (CA), y la digestibilidad in situ de la materia seca (DISMS). También fueron evaluados el pH, nitrógeno amoniacal (NH3) y la concentración de ácidos grasos volátiles (AGV) en líquido ruminal. La mejor GDP en gramos por día, de 234 g (p?0.05) se obtuvo en el T2; en contraste, el T3 mostró la menor GDP. La dieta que incluyó la mezcla de heno de alfalfa y concentrado mejoró significativamente las condiciones de las variables pH, NH3 y AGV (p?0.05).

ALFALFA VARIETIES ZONED IN THE CENTRAL CHERNOZEM ZONE OF THE RUSSIAN FEDERATION

2020 ◽  
Author(s):  
Galina Stepanova
Keyword(s):  
Medicago Sativa ◽  
Dry Matter ◽  
Maximum Yield ◽  
The State ◽  
Average Yield ◽  
State Register ◽  
Independent Evaluation ◽  
Medicago Sativa L ◽  
Alfalfa Varieties ◽  
Central Chernozem

The article describes the main morphological and biological features of alfalfa varieties included in the State register of breeding achievements approved for use in the Central Chernozem zone of Russia. A total of 32 alfalfa varieties are included in the State register. This is 9 varieties of blue alfalfa (Medicago sativa L. subsp. Sativa) of domestic selection and 8 foreign, 11 varieties of variable alfalfa (Medicago sativa L. nothosubsp. varia (Martyn) Arcang.) domestic selection and 1 variety of foreign and 3 varieties of yellow alfalfa (Medicago sativa L. subsp. falcata (L.) Arcang.). It shows the average and maximum yield of varieties determined in the process of state variety testing, as well as independent evaluation in research institutions in the region. Varieties of blue alfalfa of domestic selection Kevsala, Elena, Satellite, Vavilovskaya Yubileynaya were the most productive. The average yield of dry matter of these varieties reaches 8.4–9.2 t/ha, the maximum — 15.3–17.7 t/ha. Alfalfa varieties Timbale and Galaxy were the most productive among foreign varieties: the average yield of dry matter was 8.1 and 8.3 t/ha, the maximum – 15.5 and 17.2 t/ha. Varieties of alfalfa variable Vitalina and Vela provided an average yield of dry matter of 7.6 and 9.0 t/ha, the maximum yield reached 15.4 and 18.1 t/ha.

Szennyvíziszappal kezelt Medicago sativa L. növekedésének és rizoszféra tulajdonságainak monitorozása modellkísérletben

2008 ◽  
Vol 57 (1) ◽  
pp. 113-132 ◽  
Author(s):  
Attila Palágyi ◽  
Hamuda Hosam E. A. F. Bayoumi ◽  
Nikoletta Tóth ◽  
Mihály Kecskés
Keyword(s):  
Medicago Sativa ◽  
Medicago Sativa L

A szennyvíziszappal kezelt talajok minőségének meghatározásához elengedhetetlen a biológiai mutatók jellemzése. Jelen tanulmány célja az volt, hogy modellkísérlet segítségével megvizsgáljuk a talajokhoz (barna erdőtalaj és réti csernozjom) különböző arányban (0, 20, 40, 60 és 100% iszap:talaj) hozzáadott szennyvíziszap hatását a talaj pH-értékére, nedvességtartalmára és légzésére, valamint termőképességére (növényi szárazanyag-tartalom), enzimatikus tulajdonságaira és az ott élő mikrobiális közösségekre.Modellkísérletben, eltérő arányú iszap/talaj keveréken termesztettünk lucernát 63 napon keresztül. Mértük a relatív növényi szárazanyag-tartalmat, valamint a talaj pH-értékének és nedvességtartalmának a változását. Megvizsgáltuk továbbá a rizoszféra mikrobiális összetételét (aerob heterotróf baktériumok, aerob heterotróf spórások, cellulózbontók és foszfátoldók, fuorescens Pseudomonas ok, Sinorhizo-biummeliloti , aktinomicéták, fonalas gombák, valamint élesztők csíraszámát) és a különböző enzimek (FDA, dehidrogenáz, kataláz, ureáz, proteáz, foszfatáz, β-glükozidáz és aril-szulfatáz) aktivitását. Ugyancsak meghatároztuk a kibocsátott CO 2 alapján a talajlégzés mértékét.Eredményeink azt mutatják, hogy a szennyvíziszap hozzáadásával a talaj hosszabb ideig megőrizte nedvességtartalmát, mint a kontroll (100% talaj/0% iszap), valamint emelkedett a talaj pH-értéke is. A növények egészséges fejlődésén és növekedésén kívül, a legnagyobb növényi szárazanyag-tömeget is a nagy szennyvíziszap tartalmú minták (60–100% iszap) esetében mértük. A minták szennyvíziszap- koncentrációjának emelésével jelentősen nőtt a tenyészthető mikrobiális populációk sűrűsége is a lucerna rizoszférájában.A leggyakrabban előforduló baktériumok a következő genus okhoz tartoztak: Acinetobacter, Azotobacter, Bacillus, Brevundimonas, Cellulomonas, Chromo-bacterium, Corynebacterium, Enterobacter, Escherichia, Flavobacterium, Klebsiella, Micrococcus, Proteus, Pseudomonas, Sinorhizobium, Serratia, Stenotrophomonas, Streptococcus, Streptomyces és Zooglea . A legmagasabb fonalasgomba-populációkat a barna erdőtalajban mértük, mindkét (hódmezővásárhelyi és nyíregyházi) szennyvíziszap jelenlétében. A leggyakoribb izolátumok az Altenaria, Aspergillus, Cephalosporium, Cladosporium, Fusarium, Geotrichum, Mucor, Penicillium, Rhizopusés _s

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