FALL GROWTH AND STAND PERSISTENCE OF ALFALFA IN INTERIOR BRITISH COLUMBIA

1985 ◽  
Vol 65 (4) ◽  
pp. 935-941 ◽  
Author(s):  
DARRYL G. STOUT

Stand persistence of eight alfalfa (Medicago sativa L.) cultivars in the Interior of British Columbia was correlated to fall growth. A similar relationship has been reported for alfalfa winter survival and fall growth in other parts of North America. One alfalfa cultivar, Anik, did not fit this relationship, since it had little fall growth and low stand persistence. Although the relationship between fall growth and stand persistence appears useful for predicting cultivar stand persistence, major exceptions can occur.Key words: Winter injury, Medicago sativa, low temperature growth

1989 ◽  
Vol 69 (2) ◽  
pp. 491-499 ◽  
Author(s):  
DARRYL G. STOUT ◽  
JOHN W. HALL

Extensive winter injury, likely caused by cold damage, occurred in alfalfa (Medicago sativa L.) cultivar yield tests underway at Kamloops, British Columbia during the 1985–1986 winter. Fall yield of cultivars during the year of seeding was negatively correlated with their winter survival (r = − 0.92 in one trial with 20 cultivars or strains, and r = − 0.74 in a second study with 34 cultivars or strains). Use of fall yield to predict winter survival has the advantage over the usual procedure of measuring plant height in space-planted plots, in that both total annual yield and fall growth can be evaluated in a single study. This results in a major saving of costs. Six cultivar studies all revealed that in the interior of British Columbia spring-summer yield is positively correlated to fall yield (r = 0.24 to 0.72). For this reason, selection of a cultivar with low fall growth to obtain high winter survival is likely to result in selection of a cultivar with reduced spring-summer yield.Key words: Medicago sativa, alfalfa, low temperature growth, winter injury, cold hardiness


Author(s):  

Abstract A new distribution map is provided for Physoderma alfalfae (Pat. & Lagerh.) Karling. Hosts: Lucerne (Medicago sativa) and Medicago spp. Information is given on the geographical distribution in ASIA, India (Punjab), Iran, Israel, Pakistan, AUSTRALASIA & OCEANIA, Australia, New Zealand, EUROPE, Belgium, Britain, Cyprus, Czechoslovakia, Denmark, France, Germany, Greece, Italy, Netherlands, Portugal, Romania, Sweden, Switzerland, NORTH AMERICA, Canada (British Columbia), Mexico, USA, SOUTH AMERICA, Argentina, Chile, Ecuador, Peru.


1977 ◽  
Vol 57 (3) ◽  
pp. 873-881 ◽  
Author(s):  
R. MICHAUD ◽  
T. H. BUSBICE

Alfalfa (Medicago sativa L.) is a highly heterozygous cross-pollinating species, and most breeding efforts have been conducted on noninbred populations. The purpose of this study was to determine whether greater breeding progress could be made by selecting within partly inbred populations rather than within noninbred ones. One hundred and twenty F1 (noninbred) and 120 S1 (partly inbred) plants that were issued from crossing and selfing four alfalfa clones were evaluated for self-fertility. The most self-fertile 10% of the plants from each family were selected in each population. The selected plants within each level of inbreeding were intercrossed to produce an advanced generation in which the effectiveness of the selection was evaluated. Selection increased both self- and cross-fertility in the advanced generation. Selection was more effective at the F1 level than at the S1 level. Fertility was reduced drastically by inbreeding. The average self-fertility of the S1’s was only about 7% of the cross-fertility of their parental clones. An exponential model was proposed to describe the relationship between seed setting and the coefficient of inbreeding in the developing zygote. This model explained 95% of the variation among 11 unselected populations having differing levels of inbreeding.


1982 ◽  
Vol 62 (2) ◽  
pp. 399-405 ◽  
Author(s):  
J. S. McKENZIE ◽  
G. E. McLEAN

Plants propagated from single plant selections of the alfalfa cultivars Saranac and Luna (Medicago sativa L.), Beaver (M. media Pers.) and Anik (M. falcata L.) were transplanted into the field in May and subjected to a range of freezing temperatures at 3-wk intervals during August and September. A portable field freezing chamber was used to study the influence of frost on leaf injury in the fall and winterkill following the severe 1977–1978 winter. Leaves of all plants had the capacity to harden during the fall, but the selection from Anik was consistently the most frost hardy. Temperatures ranging from −4 to −5 °C in mid-August caused 50% leaf injury to the selections of Beaver, Saranac and Luna, while in late September, temperatures ranging from −9.5 to −10.5 °C were required to produce similar amounts of injury. In the Anik selection, −6 °C in mid-August caused 50% leaf injury, but in late September −12.5 °C caused less than 35% injury. Thus, the Anik selection appeared to start hardening about 3 wk earlier than all other selections. In all plants, the potential for winter injury during the 1977–1978 winter increased as a result of leaf frost damage during mid-August and early September in 1977. The application of these results to the winter survival of seedling stands of alfalfa is discussed.


1984 ◽  
Vol 62 (7) ◽  
pp. 1387-1396
Author(s):  
James E. O'Hara

Baeomyia n.g. is described for a group of small (2–3 mm long) tachinids belonging to the Siphona group of the Siphonini. All known specimens were collected in western North America, with two species recorded from southern British Columbia (Baeomyia xanthogaster n. sp. and Baeomyia juniperi n. sp.) and three species recorded from desert localities in the American Southwest (type-species Baeomyia hurdi (Reinhard), Baeomyia antennata n. sp. and Baeomyia sonorensis n. sp.). Keys to adult males and females are provided for separation of species. Systematics of the Siphonini and Siphona group are reviewed, including a discussion of the synapomorphies upon which each is defined. Baeomyia species are inferred to form a monophyletic taxon within the Siphona group on the basis of five synapomorphies, though the relationship between the genus and other Siphona group taxa is unresolved. The apparent disjunction of Baeomyia species into northern and southern ranges may be the result of relatively recent speciation events, because differences among species are slight. A detailed zoogeographic analysis of the distribution pattern must await further phylogenetic data.


1987 ◽  
Vol 67 (3) ◽  
pp. 827-830 ◽  
Author(s):  
M. R. HANNA ◽  
H. C. HUANG

Barrier is the first Canadian cultivar of alfalfa (Medicago sativa L.) developed with resistance to verticillium wilt disease. It also has very good resistance to bacterial wilt. Barrier is adapted to the irrigated areas in Southern Alberta and British Columbia where these diseases are prevalent.Key words: Medicago sativa L., alfalfa, cultivar description, verticillium wilt, bacterial wilt


1973 ◽  
Vol 53 (4) ◽  
pp. 773-777 ◽  
Author(s):  
D. H. HEINRICHS

Winter injury occurring at Swift Current, Saskatchewan, was recorded in 17 tests during the period 1962–72. Cultivars developed in the Northern Great Plains Region of the USA and in Canada were generally more winter-hardy than cultivars developed in other regions of North America or in Europe. Cultivars classified as Medicago media Pers. were more winter-hardy than those classified as Medicago sativa L. Very few USA cultivars were more winter-hardy than Vernal, but most Canadian cultivars were. In nonhardy cultivars winter injury never occurred during the first winter, but it often occurred in the second winter and frequently in the third winter. There was considerably more winter injury among alfalfa cultivars on irrigated land than on dry land. Based on results from these tests, 50 cultivars and strains have been classified for relative winterhardiness under climatic conditions in southern Saskatchewan, Canada.


1992 ◽  
Vol 72 (3) ◽  
pp. 931-936 ◽  
Author(s):  
Darryl G. Stout ◽  
S. N. Acharya ◽  
H. C. Huang ◽  
M. R. Hanna

Single plants of 12 alfalfa (Mediccigo sativa L.) cultivars, chosen to represent a range of winter hardiness and resistance to verticillium wilt (Verticillium albo-atrum), were space planted to determine the time of plant death during the year. Plant mortality was assessed in spring and fall for three consecutive years. The relationship between plant survival during summer or winter and the cultivars’ resistance to verticillium wilt or fall growth was examined. During the first 2 yr of this field study, natural mortality during both summer and winter ranged from 1.0 to 2.1%. But by the third year an average of 9% of the plants died during the summer. Survival during the third summer was correlated (r = 0.76, P = 0.004) with the veritcillium wilt resistance measured using a greenhouse screening test, but was not correlated with fall growth of the cultivars. During the third winter, plant death for all cultivars averaged 67%. Survival of a cultivar during the winter was negatively correlated (r = −0.84, P = 0.001) with its fall growth, but not with its verticillium wilt resistance. These results indicate that programs to develop alfalfa cultivars with long-term persistence in the interior region of British Columbia should include both fall growth and verticillium wilt resistance in their selection criteria.Key words: Verticillium wilt, winter injury, fall dormancy, winter hardiness, stand persistence


1986 ◽  
Vol 66 (3) ◽  
pp. 585-589
Author(s):  
J. H. ELGIN Jr. ◽  
C. M. RINCKER

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


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