Genetic diversity in pea germplasm from Vavilov Institute and ICARDA collections for black spot resistance and agronomic merit

Priliouk, L., Vavilov, N.I.,

All-Russian Res. Inst. of Plant Ind.
B.Morskaya Str. 42.
St.Petersburg, 190000, Russia

Robertson, L.,

ICARDA, Aleppo, Syria

Francis, C.,

CLIMA, Perth, Australia

Khan, T.,

Agriculture WA, Perth, Australia

Gorfu, D., and Bejiga, G.

Ethiopian Agricultural Research Organization
Holetta, Ethiopia

Mycosphaerella pinodes (Berk. Et Blox.) Vest. is a widespread fungus infesting peas and is considered particularly aggressive. It can cause early top defoliation in the crop. A survey of the large pea collections at Vavilov Institute (VIR) and ICARDA might identify new sources of resistance to this fungus.

A set of 474 pea accessions originating from 28 countries in the Vavilov Institute was evaluated for morphological and agronomic traits during the 1997-1998 growing season at Tel Hadia Station of ICARDA near Aleppo. Entries were planted in two replications with three local controls, in a randomized design. Most of the lines demonstrated good agronomic potential, and the plants were free of infestation under the dry Syrian climate. To screen pea cultivars for resistance to Mycosphaerella blight diseases under field conditions the harvested pea seeds together with an added set from ICARDA collection were transferred to Holetta Research Station in Ethiopia where the disease is endemic. Severe infection of black spot blight occurred on controls and the majority of tested lines.

Out of 581 lines evaluated, 56 lines were recorded as being promising: 16 possessed good agronomic merit; 40 lines with moderate infection levels (scored less than 2.5) were recorded as resistant, and 17 of these also displayed good agronomic potential. Resistant accessions were from 10 countries (Table 1). In experiments of Yankov (1) it was shown that tolerant varieties were from locations favorable for invasion. Significantly, in our experiment resistance appears to occur in lines originating from many different sources. The potentially resistant lines identified were multiplied in New Zealand courtsey of Mr. Adrian Russell, and are currently being studied at Medina, WA, to assess resistance in a widely different environment.

Table 1. Source of germplasm and frequency within each source of resistance to Mycosphaerella blight


Origin

Lines assessed

Resistant lines

% of assessed


Afghanistan

52

4

7.7

China

79

7

8.9

Ethiopia

105

9

8.6

Greece

42

6

14.3

Italy

30

1

3.3

Kazakhstan

15

3

20

Kyrgyzstan

5

3

60

Portugal

16

1

6.2

Turkey

105

5

4.8

Uzbekistan

14

1

7.1


  1. Yankov, I.I. 1997. Ann. Appl. Botany, Genetics and Breeding (in Russian) 152: 87-95.