EFFECT OF GENERATION AND LOCATION OF SEED PRODUCTION ON GROWTH HABIT AND ANTHRACNOSE RESISTANCE IN ARC ALFALFA

1986 ◽  
Vol 66 (3) ◽  
pp. 585-589
Author(s):  
J. H. ELGIN Jr. ◽  
C. M. RINCKER
Keyword(s):  
Medicago Sativa ◽  
Seed Production ◽  
Growth Habit ◽  
The Other ◽  
Anthracnose Resistance ◽  
Field Growth ◽  
Medicago Sativa L ◽  
Growth Habits ◽  
Fall Growth

Thirty-one seedlots of Arc alfalfa (Medicago sativa L.), produced between 1971 and 1974 at Prosser, Wash.; Stanfield, Oreg.; and Shafter and Tehachapi, Calif., were evaluated for shifts in field growth habits (regrowth after cutting, winter injury, and date of flowering) and greenhouse anthracnose resistance. Seedlots represented one (Syn 2), two (Syn 3), and three (Syn 4) generations of increase beyond the original Syn 1 lot, grown under four diverse environments. Results indicated a tendency for shift in regrowth rate among the Syn 3 and Syn 4 generation seedlots produced at Shafter, Calif. No shift in regrowth rate was observed for the other locations and no significant trends away from the original lot were observed for winter injury, date of flowering or anthracnose resistance.Key words: Medicago sativa L., seed production, genetic shifts, anthracnose resistance, fall growth, regrowth

IRRIGATION MANAGEMENT OF ALFALFA FOR SEED

1977 ◽  
Vol 57 (3) ◽  
pp. 891-896 ◽  
Author(s):  
K. K. KROGMAN ◽  
E. H. HOBBS
Keyword(s):  
Soil Moisture ◽  
Medicago Sativa ◽  
Seed Production ◽  
Irrigation Management ◽  
Growing Season ◽  
Moisture Stress ◽  
Field Plot ◽  
Southern Alberta ◽  
Medicago Sativa L ◽  
Seed Yields

In field plot experiments conducted in southern Alberta over a 6-yr period, highest seed yields of alfalfa (Medicago sativa L. cv. Beaver) were obtained with one or two irrigations in the first half of the growing season. In outdoor lysimeters protected from rain, moisture stress for more than 8 days before seed ripening severely reduced seed production. Under field conditions, stored soil moisture from irrigation during the vegetative stage of growth plus occasional rain in July and August permitted irrigation of alfalfa for seed to be stopped at the bud to early bloom stage (June to early July).

Phosphorus seed coatings for pasture species. II. Comparison of effectiveness of phosphorus applied as seed coatings, drilled or broadcast, in promoting early growth of phalaris (Phalaris aquatica L.) and lucerne (Medicago sativa L.)

1988 ◽  
Vol 39 (3) ◽  
pp. 447 ◽  
Author(s):  
JM Scott ◽  
GJ Blair
Keyword(s):  
Medicago Sativa ◽  
Plant Height ◽  
Early Growth ◽  
The Other ◽  
Fertilizer Treatment ◽  
Seed Coating ◽  
Phalaris Aquatica ◽  
Medicago Sativa L ◽  
Application Methods ◽  
P Sources

The relative efficiency of phosphorus (P) seed coatings and drilled and broadcast applications of P was investigated in a glasshouse experiment conducted with phalaris (Phalaris aquatica L.) and lucerne (Medicago sativa L.) in P-deficient soil. Two P sources (monocalcium phosphate [MCP] and dicalcium phosphate [DCP]) were used at three rates in seed coatings (0, 5 and 10 kg P ha-1) or at six rates each of drilled or broadcast applications (0, 2.5, 5, 10, 20 and 40 kg P ha-1). MCP coatings severely reduced lucerne emergence and hence yield, but had little effect on phalaris emergence. No other fertilizer treatment affected emergence. The height of phalaris plants at 27 days after sowing (d.a.s.) was increased as much by seed coatings containing MCP at 5 kg P ha-1 as by drill or broadcast applications of MCP at 20 kg P ha-1. Plant height of the MCP seed coating treatments was also less variable than the other application methods, suggesting that the coatings provided more uniform access to P. Seed coatings containing DCP at 10 kg P ha-1 increased phalaris plant height more than did drilled or broadcast applications at 40 kg P ha-1, but there was no effect of any DCP treatment on lucerne growth at 27 d.a.s. The relatively large differences observed in plant height between different application methods at 27 d.a.s. diminished over time until, at 57 d.a.s., only small differences were evident. The dry matter yield and P content of both species were increased by increasing rates of MCP, but DCP had little effect at any rate. The reduced differences between the seed coating treatments and the other application methods at harvest may have been due to the limited soil volume of the pots used; further work is necessary in larger soil volumes to determine the significance of the early growth advantage conferred on phalaris by the phosphorus seed coatings, and to find ways of protecting lucerne from soluble P sources during germination.

Relationships between inbreeding, meiotic irregularity, and fertility in alfalfa

1986 ◽  
Vol 28 (1) ◽  
pp. 130-137 ◽  
Author(s):  
S. E. Smith ◽  
R. P. Murphy
Keyword(s):  
Medicago Sativa ◽  
Seed Production ◽  
Inbreeding Depression ◽  
Pollen Mother Cell ◽  
Mother Cell ◽  
Pollen Parent ◽  
Meiotic Behavior ◽  
Negatively Associated ◽  
Meiotic Irregularity ◽  
Medicago Sativa L

Fertility (seed production) in alfalfa (Medicago sativa L.) is severely depressed by inbreeding; however, little is known of the factors directly responsible for this depression. Irregularities in meiotic behavior could be partially responsible for the inbreeding depression in fertility observed. This study considered relationships between fertility, inbreeding, and irregularity in microsporogenesis. Fertility declined markedly with inbreeding in the materials examined (S0–S3). Irregularity in microsporogenesis, as measured by the percent irregular quartets, (i.e., quartets with micronuclei, supernumerary microspores, or irregular cytokinesis) increased significantly with inbreeding. Increases in quartet irregularity were associated with increases in the number of univalents per pollen mother cell observed at metaphase I. Considering all materials studied, the percentage of irregular quartets was negatively and significantly correlated with fertility as both a seed and a pollen parent. In more detailed analyses, it was observed that the percent irregular quartets was negatively associated with fertility as a pollen parent only when levels of irregularity were relatively high. No association was observed between the percent irregular quartets and fertility when levels of irregularity were relatively low.Key words: Medicago, microsporogenesis, seed production, breeding, fertility.

EFFECTS OF ESTABLISHMENT METHOD AND A RAPESEED COMPANION CROP ON ALFALFA SEED YIELD

1987 ◽  
Vol 67 (1) ◽  
pp. 263-266 ◽  
Author(s):  
J. WADDINGTON ◽  
N. MALIK
Keyword(s):  
Medicago Sativa ◽  
Seed Production ◽  
Seed Yield ◽  
Brassica Campestris ◽  
Establishment Method ◽  
Alfalfa Seed ◽  
Medicago Sativa L ◽  
Companion Crop

In two experiments at Melfort using alfalfa (Medicago sativa L. ’Beaver’) seeded at a rate of 2 kg ha−1 with and without a Polish rapeseed (Brassica campestris L. ’Candle’) companion crop seeded at 5.5 kg ha−1, rapeseed yields in the establishment year were maximum when alfalfa and rapeseed were mixed and planted in 15-cm rows. Alfalfa showed no consistent seed yield differences between broadcast seeding, seeding in 15- or 61-cm rows, or seeding with or without the companion crop.Key words: Alfalfa, rapeseed, Brassica campestris, seed production

Evaluation of Rhizobium inoculant formulations for alfalfa yield and N fixation

2007 ◽  
Vol 87 (2) ◽  
pp. 267-272 ◽  
Author(s):  
J. Diane Knight
Keyword(s):  
High Risk ◽  
Medicago Sativa ◽  
Sinorhizobium Meliloti ◽  
The Other ◽  
N Fixation ◽  
Biological N Fixation ◽  
Small Seed ◽  
Alfalfa Seed ◽  
Medicago Sativa L

Because of its small seed size, alfalfa (Medicago sativa L.) typically is seeded at a shallow depth, putting Rhizobium inoculated onto the seed coat at a high risk of desiccation. Granular inoculants may provide a superior delivery formulation for Rhizobium because the inoculant can be placed deeper in the soil than the seed, where it is protected from desiccation. Sinorhizobium meliloti cv. Beaver delivered as (1) pre-inoculated alfalfa seed from the inoculant manufacturer, (2) commercial peat-based, self-sticking inoculant applied on-site, and (3) granular inoculant placed with the seed or (4) banded below and to the side of the seed was evaluated against uninoculated alfalfa controls at three field sites in Saskatchewan. Overall, alfalfa inoculated with the granular formulation placed below and to the side of the alfalfa seed was among the highest biomass producer in the establishment year, although it did not exhibit superior nodulation or biological N fixation compared with the other treatments. Any advantage conferred by the granular inoculant in the establishment year did not persist through the first and second production years. Under the conditions of this study, the delivery formulation had no long-term affect on alfalfa productivity, nodulation and biological N fixation. Furthermore, none of the inoculant treatments were consistently superior to the uninoculated controls. Key words: Alfalfa, granular inoculant, peat inoculant, pre-inoculated seed, Medicago sativa L., Sinorhizobium meliloti

Effects of tall wheatgrass windbreaks on hay production of three alfalfa varieties at a semiarid location in Saskatchewan

1995 ◽  
Vol 75 (4) ◽  
pp. 877-881
Author(s):  
J. Waddington ◽  
H. Steppuhn
Keyword(s):  
Medicago Sativa ◽  
Soil Water ◽  
Dry Matter ◽  
Dry Matter Yield ◽  
Thinopyrum Ponticum ◽  
Tall Wheatgrass ◽  
Medicago Sativa L ◽  
Alfalfa Varieties ◽  
Growth Habits ◽  
Semi Arid

Soil water limits alfalfa (Medicago sativa L.) growth in semi-arid southwest Saskatchewan. The dry matter yields of three alfalfa varieties with contrasting growth habits were compared when grown between tall wheatgrass [Thinopyrum ponticum (Podp.) Barkworth & D.H. Dewey] windbreaks spaced on 15-m centres, and when grown without windbreaks. Over a 7-yr period, and including the area occupied by the windbreaks, alfalfa yields were 2110 kg ha−1 dry matter on average. This was 40% more dry matter than from alfalfa grown outside the windbreaks. There were no consistent yield differences between the three varieties, but Beaver, a branch-rooted variety, produced more dry matter than Angus, a tap-rooted variety with fast regrowth potential, and Rangelander, a creeping-rooted variety, in the years when differences reached significance, and on average over the 7-yr period. Alfalfa regrowth was sufficient for a second cut in 3 of 7 yr. Cultivating to a depth of 35 cm with a Paraplow subsoiler prior to seeding had no effect on hay yields. Key words:Medicago sativa, dry matter yield, snow management

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