Study of Genetic Diversity, Heritability and the Correlation of Different Traits in Alfalfa (Medicago sativa L.) Related to Alfalfa Weevil (Hypera postica Gyll.) Damage in Alfalfa Germplasm

AbstractLarval and adult populations of the Egyptian alfalfa weevil (EAW) Hypera brunneipennis (Boheman) (Coleoptera: Curculionidae) was monitored after application of the entomopathogenic fungus Beauveria bassiana in the alfalfa field (Medicago sativa L.) in two successive seasons 2014/2015 and 2015/2016. The second and last generation of the weevil on April 10, 2016, was controlled by only one application with the conidiospores of the entomopathogenic fungus B. bassiana (3 × 108 spores/ml). Accordingly, the larval population decreased from 16.07 ± 1.09 in season 2015/2016 to 7.37 ± 0.05 individuals/50 sweep net double strokes in season 2016/2017. Also, the adult weevil’s population decreased from 5.66 ± 0.8 to 2.55 ± 0.6 individuals/50 sweep net double strokes in the two seasons, respectively. 39.66% mortality rate was recorded in the Hypera brunneipennis adults aestivated under loose bark of the surrounding eucalyptus trees, which received the application of B. bassiana in the field. Another application with the fungus, targeting the second generation of the pest adults in alfalfa each season, will undoubtedly lead to a further decrease in the pest population.

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Demographic studies of Oomyzus incertus (Hymenoptera: Eulophidae), a larval parasitoid of Hypera postica (Coleoptera: Curculionidae), treated with four organophosphorous insecticides

The Canadian Entomologist ◽

10.4039/n04-067 ◽

2005 ◽

Vol 137 (4) ◽

pp. 488-491

Author(s):

Qodrat Sabahi ◽

Khalil Talebi

Keyword(s):

Life Cycle ◽

Medicago Sativa ◽

Fourth Instar ◽

Northern Iran ◽

Alfalfa Weevil ◽

Hypera Postica ◽

Larval Parasitoid ◽

Organophosphorous Insecticides

The alfalfa weevil, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), can severely damage the first cutting of alfalfa, Medicago sativa L. (Fabaceae), in much of Iran. The pest has been parasitized by several parasitoids including Oomyzus incertus (Ratzeburg) (Hymenoptera: Eulophidae), a gregarious larval endoparasitoid. This wasp can parasitize up to 30% of weevil larvae in alfalfa fields in northern Iran. It produces three to four generations per year, and the female prefers the fourth instar of the host for oviposition. Each female lays 2 to 22 eggs per host, which hatch within 47–60 h. The life cycle is completed in about 2 weeks, upon pupation inside the host. This species is predominantly present during the summer months in alfalfa fields (Streams and Fuester 1967).

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Genetic Diversity of Some Mediterranean Populations of the Cultivated Alfalfa (Medicago sativa L.) Using SSR Markers

Pakistan Journal of Biological Sciences ◽

10.3923/pjbs.2008.1923.1928 ◽

2008 ◽

Vol 11 (15) ◽

pp. 1923-1928 ◽

Cited By ~ 4

Author(s):

L. Touil ◽

F. Guesmi ◽

K. Fares ◽

C. Zagrouba ◽

A. Ferchichi

Keyword(s):

Genetic Diversity ◽

Medicago Sativa ◽

Ssr Markers ◽

Mediterranean Populations ◽

Medicago Sativa L

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Genetic diversity of salt tolerance in tetraploid alfalfa (Medicago sativa L.)

Acta Physiologiae Plantarum ◽

10.1007/s11738-019-2993-8 ◽

2020 ◽

Vol 42 (1) ◽

Cited By ~ 4

Author(s):

Mohamed Ali Benabderrahim ◽

Marwa Guiza ◽

Mansour Haddad

Keyword(s):

Genetic Diversity ◽

Salt Tolerance ◽

Medicago Sativa ◽

Medicago Sativa L

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Evaluation of Alfalfa Weevil (Coleoptera: Curculionidae) Densities and Regrowth Characteristics of Alfalfa Grazed by Sheep in Winter and Spring

Journal of Entomological Science ◽

10.18474/0749-8004-39.4.598 ◽

2004 ◽

Vol 39 (4) ◽

pp. 598-610 ◽

Cited By ~ 3

Author(s):

Hayes B. Goosey ◽

Patrick G. Hatfield ◽

Sue L. Blodgett ◽

S. Dennis Cash

Keyword(s):

Crude Protein ◽

Forage Yield ◽

Sheep Grazing ◽

Alfalfa Weevil ◽

Nutrient Quality ◽

Hypera Postica ◽

Medicago Sativa L ◽

The Impact ◽

Neutral Detergent Fibers ◽

Crop Health

Fall regrowth of alfalfa, Medicago sativa (L.), serves as a major source of winter pasture for Montana sheep producers. In years of drought, alfalfa fields are extensively winter/spring grazed; however, the impact on crop health is unknown. Alfalfa paddocks were continuously grazed for 95 d in 2002 and 98 d in 2003 during winter and spring to determine the impact on spring and summer alfalfa regrowth, nutrient quality characteristics, and alfalfa weevil, Hypera postica Gyllenhal, densities. Grazed and non-grazed forage yield, crude protein (%), and acid and neutral detergent fibers (%) did not differ at harvest (P> 0.17) during either study year. Acid and neutral detergent fibers (kg/ha) were greater (P < 0.05) in non-grazed compared to grazed plots during 2002–2003. Alfalfa weevil densities were lower in grazed than non-grazed plots (P< 0.03) over four sampling dates during both study years. Winter/spring sheep grazing appears to offer potential for alfalfa weevil management without compromising yield or nutritive factors of subsequent alfalfa production.

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Resistance to the alfalfa weevil in the Iranian collection of Medicago sativa

Tropical Grasslands - Forrajes Tropicales ◽

10.17138/tgft(8)263-279 ◽

2020 ◽

Vol 8 (3) ◽

pp. 263-279

Author(s):

Mohammad Reza Abbasi

Keyword(s):

Medicago Sativa ◽

Plant Height ◽

Morphological Traits ◽

Growth Habit ◽

Breeding Programs ◽

Alfalfa Weevil ◽

Hypera Postica ◽

Positive Linear Relationship ◽

Fall Dormancy ◽

Range Test

The Iranian collection of Medicago sativa (alfalfa, 502 accessions) was evaluated under field conditions to identify variation in resistance to the alfalfa weevil (Hypera postica Gyllenhal) between accessions over 4 years. Twenty-one accessions were identified as resistant (score 3) to semi-resistant (score 5) based on K-means cluster analysis. These materials were grouped into 10 groups by means of Duncan's Multiple Range Test. Susceptibility to alfalfa weevil was significantly correlated with some of the agro-morphological traits such as plant height (r = 0.314, P<0.01), regrowth rate (r = 0.435, P<0.01) and fall dormancy score (r = 0.284, P<0.01). In general, the resistant germplasm originated from elevated regions at high latitudes, where a co-evolution between the plant and the pest may have taken place. Multiple regression analysis showed a positive linear relationship between susceptibility to the alfalfa weevil and traits such as growth habit, plant height, length and width of the central leaflet and regrowth rate. The resulting bi-plot based on factor analysis ranked accessions for susceptibility to the pest. The identified germplasm should prove useful in alfalfa breeding programs to develop accessions resistant to the alfalfa weevil.

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Effect of phenotypic recurrent selection on genetic diversity of non-dormant multifoliolate lucerne (Medicago sativa L.) populations

Crop and Pasture Science ◽

10.1071/cp14280 ◽

2015 ◽

Vol 66 (11) ◽

pp. 1190 ◽

Cited By ~ 1

Author(s):

A. Odorizzi ◽

E. M. C. Mamani ◽

P. Sipowicz ◽

B. Julier ◽

J. Gieco ◽

...

Keyword(s):

Genetic Diversity ◽

Medicago Sativa ◽

Recurrent Selection ◽

Selection Process ◽

Phenotypic Recurrent Selection ◽

Total Genetic Diversity ◽

Significant Difference ◽

Medicago Sativa L ◽

Two Populations

The nutritional quality of lucerne (alfalfa, Medicago sativa L.) plants correlates positively with the presence of multifoliolate (MF) leaves. Using phenotypic recurrent selection, we developed populations with an increased percentage of MF expression from 6.7% in the original population (C0) to 77.7% in the fourth cycle (C4). The effect of selection on genetic diversity within and among populations was evaluated. The populations C0 and C4 were represented by 40 plants genotyped by using 25 simple sequence repeats (SSR). The number of alleles per locus was large in both C0 and C4, averaging 6.28. The within-population genetic diversity (HE) overall estimation was 0.723 for C0 and 0.726 for C4, the absence of significant difference between the two populations indicating that the genetic diversity was as large in C4 as in C0. The Nei’s population differentiation (GST) overall estimation was 0.013, meaning that only 1.3% of the total genetic diversity was between populations and 98.7% was within populations. An efficient selection process was conducted without any increase in inbreeding or genetic drift.

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