Abiotic and Biotic Factors Affecting Resting Spore Formation in the Mite Pathogen Neozygites floridana
Table 1
Effect of different combinations of photoperiod, mean temperature, temperature drop, light intensity, and light quality on resting spores produced in N. floridana-killed T. urticae by one isolate from Norway (NCRI271/04) and one from Brazil (ESALQ1420).
Photoperiod
Mean temperature (temperature drop1) °C
Host plant
conditions
Light intensity (light quality)2
Isolate ESALQ1420
Isolate NCRI271/04
No. of mites
Hyphal bodies (%)
Resting spores (%)
No. of mites
Hyphal bodies (%)
Resting spores (%)
12L : 12D
25 (−10)
Nonsenescent
165–243 (2)
40
22.5
0
47
17.0
0
25 (−5)
42
35.7
0
47
25.5
0
25 (0)
40
30.0
0
46
26.1
0
25 (5)
40
20.0
0
46
15.2
0
15
42–46 (1)
60
78.3
0
59
79.7
0
10L : 14D
15 (−10)
Nonsenescent
165–243 (2)
72
50.0
0
69
73.9
0
247–280 (1)
72
55.6
0
69
66.7
0
30–35 (2)
72
54.2
0
72
38.9
0
42–46 (1)
69
68.1
0
72
56.9
1.4
Senescent
165–243 (2)
72
55.6
0
72
59.7
0
247–280 (1)
71
73.2
0
72
52.8
2.8
30–35 (2)
69
68.1
0
60
56.7
5.0
42–46 (1)
60
81.7
0
63
68.3
3.2
15
Nonsenescent
165–243 (2)
72
51.4
0
69
65.2
0
247–280 (1)
72
68.1
1.4
64
75.0
0
30–35 (2)
72
75.0
0
72
63.9
0
42–46 (1)
72
55.6
0
72
50.0
4.2
Senescent
165–243 (2)
72
86.1
0
72
58.3
1.4
247–280 (1)
72
66.7
0
72
69.4
0
30–35 (2)
69
78.3
0
60
70.0
1.7
42–46 (1)
72
68.1
0
60
58.3
0
13
Nonsenescent
60
91.7
0
60
70.0
0
11
42–46 (1)
111
73.0
51.5
102
93.6
4.7
6
60
83.3
0
58
62.1
0
14L : 10D
15
Nonsenescent
42–46 (1)
59
67.8
0
60
78.3
0
16L : 08D
58
93.1
0
59
75.7
1.7
Temperature drop: fall of the temperature for 4 h during the light period. 2Light intensity (µmol m−2 s−1) and light quality (1 = warm white fluorescent lamps Philips-Master TL-D 90 and 2 = cool white fluorescent lamps Mitsubishi—40SW (Ra61)).
