TABLE 44 Greening. psyllids and psyllid parasites and citrus canker in Saudi Arabia as of 1983

Location

Altitude (m)

Presence of greening based on

Presence of Asian psylla (Diaphorina citri)

Presence of African psylla (Trioza erytreae)

Presence of Tetrastychus radiatus parasite of D. citri

Presence of citrus canker

Symptom

Electron microscopy
Usfan 150 Not clear No Yes No Yes No
Khulais 200 Not clew No Yes No Yes1 No
Haddat Ash Sham 200 Not clear ND˛ Yes No D. citri nymphs parasitized No
Zaimah 500 Yes Yes Yes No D. citri nymphs parasitized No
Wadi Nahman 500 Yes ND Yes No Yes No
Taif 1700 Yes Yes Yes No NSł No
Turabah 1400 Yes Yes Yes No Yes No
Khurmah 1400 Yes Yes Yes No NS No
Boua 1500 Yes Yes None seen No None seen No
Bishah 1000 Yes Yes Yes No None seen No
Al Ullayah 2000 No ND No No No No
Brehim Khaibar 1500 Yes Yes Yes Yes4 Yes No
Najran 900 No No No Yes No No
Jizan 20 No No No No No No
Sabia 100 No No No No No Yes
Fayfa 1200-1800 Not clear Yes No Yes4 No No
Ad Darb   No ND No No No No
Muraibah   No ND No No No No
Al Ugdah   No ND No No No No
Medina area   No ND No No No No

Notes:
1 Cheiloneurus cyanonotus, a psyllid hyperparasite, was present.
2 ND: not done.
3 NS: not surveyed in December 1983.
4 Based on the typical T. erytreae-induced leaf galls.

TABLE 45 Monthly mean temperatures (T) in °C, relative humidity (RH) and saturation deficit (SD) in millibars, at midday for six stations in Saudi Arabia

Station (altitude)

Month
J F M A M J J A S O N D
Najran T 26.3 26.7 28.1 34.0 36.0 38.5 38.8 38.2 33.3 30.2 21.2 26.2
(1150 m) RH 32 27 41 18 17 10 11 13 17 19 30 24
SD 22.9 25.2 22.0 43.1 48.8 60.6 60.8 57.3 41.9 34.3 17.4 255
Bishah T 28.4 26.4 29.4 34.0 35.6 38.7 38.7 39.1 35.8 31.8 29.5 26.2
(1040 m) RH 18 17 23 13 13 4 7 6 7 9 15 15
SID 31.7 28.2 31.1 45.7 50.0 65.3 63.3 64.9 54.0 41.9 34.6 30.1
Jizan T 30.1 30.0 31.9 34.9 37.0 38.2 38.0 38.5 37.7 34.7 33.9 30.7
(40 m) RH 63 53 61 49 53 49 47 47 49 46 53 59
SID 15.6 19.7 18.2 28.2 29.1 34.7 34.5 35.7 32.9 29.5 24.5 17.8
Khamis Mushait T 22.4 22.6 22.4 26.1 28.3 31.6 30.4 30.9 29.1 26.3 24.7 22.9
(2000 m) RH 29 36 47 30 26 49 25 25 21 24 29 29
SID 18.9 17.3 14.1 23.3 28.1 23.4 32.1 33.0 31.2 25.6 21.7 19.5
Taif T 24.4 23.9 25.4 29.5 33.1 35.2 34.3 34.9 33.6 29.7 26.1 25.6
(1634 m) RH 46 58 53 27 25 16 17 17 20 21 31 31
SID 16.3 12.3 15.0 29.7 37.5 47.2 44.4 45.9 41.2 32.6 23.0 22.4
Medina T 24.6 26.5 28.6 35.0 39.5 42.5 39.3 43.2 41.5 36.5 30.3 27.9
(500 m) RH 25 20 16 15 16 7 9 10 10 24 30 40
SD 22.8 27.3 32.5 47.2 59.4 77.6 64.0 77.9 71.2 45.6 29.8 22.2