Íslenskar landbúnaðarrannsóknir - 01.09.1977, Page 44

42 ÍSLENZKAR LANDBÚNAÐARRANNSÓKNIR
TABLE 2. SUMMARISED SYMBIOTIC CHARACTERISTICS OF
RHIZOBIUM STRAINS (EXPERIMENT 1)
Days to lst nodule Dry weight (mg)
Source 12°C Range 20°C Range 12°C Range 20°C Range
ICELAND
Means of:
21 strains from South .... . . . . 25.7 18.5-44.5 11.5 9.1-13.3 4.4 2.0-8.2 10.7 1.2-17.5
13 strains from North . . . . .. .. 24.3 18.3-28.1 11.9 9.0-15.5 6.4 4.1-8.2 14.7 7.3-23.2
6 strains from East .... 23.7 20.9-25.8 11.9 11.2-13.0 5.1 2.6-7.6 11.9 3.2-19.4
SWEDEN
Means of 6 strains .... 20.6 17.6-22.9 11.3 9.1-13.7 6.1 5.2-8.0 18.6 15.9-21.3
WALES
Means of 10 strains .... 21.3 18.5-25.3 11.3 9.2-13.3 4.0 1.8-5.2 14.6 3.8-23.8
ENGLAND
Means of 4 strains .... 26.3 23.9-31.8 10.2 9.5-11.4 6.1 4.2-8.6 22.0 20.5-22.8
Best strains from:
Iceland (38) .... 21.8 10.7 8.2 8.5
(33) .... 18.3 12.0 7.2 21.1
(26) .... 23.5 9.0 8.2 7.3
(46) .... 24.1 11.8 7.6 19.4
Sweden (83,2009) .... 17.6 9.1 8.0 20.1
Wales (65) .... 20.6 10.5 5.2 23.8
England (75) .... 24.8 11.4 8.6 22.8
and between populations from different areas
(P<0.001). Temperature had a significant in-
fluence on yield (P<0.001), with the dry
weight of plants inocuiated with the most
effective strains being about 8—9 mg at
12°C and 21—24 mg at 20°C. There was
no strain x temperature interaction. However,
although not significant, strain 26 did
produce the reverse effect with the highest
yield (8.2 mg) being produced at 12°C as
compared with 7.3 mg at 20°C.
Analysis of variance for the date of prim-
ary nodulation is summarised in Table 4.
The difference between strains was not signi-
ficant, but temperature had a significant
influence on the date of nodulation. When
TABLE 3. SUMMARIZED ANALYSIS OF VARIANCE FOR SHOOT
DRY WEIGHT. EXPERIMENT 1.
Item d.f. M.S. V.R.
Total 119
AU strains 59 240.97 1.51***
Strains from Sweden 5 31.63 0.20 N.S.
Strains from Iceland 39 219.92 1.38***
Strains from Wales 9 271.21 1.69 N.S.
Strains from England 3 26.57 0.17 N.S.
Between groups 3 987.18 6.18***
Temperature 1 21335.50 133.5***
Interaction (S X T) 59 133.34 0.84 N.S.
Error 1037 159.787
*** P < 0.001, N.S. : Not significant