Screening of commercial wheat varieties to spot blotch

under controlled and field conditions

Shamim Iftikhar, Shahzad Asad and Muhammad Fayyaz

Crop Diseases Research Programme, Institute of Plant and Environmental Protection, NARC, PARC,

Islamabad.

• Spot blotch of wheat caused by Bipolaris sorokiniana, is one of the major cereal disease in warmer and humid wheat growing regions of the world.

• Epidemic-------observed in Indian Punjab with the dominant pathogen Bipolaris sorokinianafollowed by Fusarium spp. ((Mahto et al., 2002).

• Epidemic------- Abnormal weather conditions

including high moisture and temperature

Bipolaris sorokiniana(Major fungus in Pakistan)

• Seed and soil borne pathogen affects the seed germination and seedling emergence.

– Seedling blight – Root rot – Spot blotch.

(Bhatti et al., 1986; Hafiz, 1986; Kishwar et al., 1992; Iftikhar et al., 2006).

Yield Losses

• 27% -- 56.6 % (1998-99) in north eastern and north western plains of India (Satvinder et al. (2002)

• Up to 15% on several farms over a number of years in Bangladesh (Alam et al., 1994)

• Up to 23.8% in Nepal (Shrestha et al., 1997)

How we manage the Disease and Increase the productivity

• The best, cheapest, environment friendly and the easiest way of

managing the disease and increasing the productivity.

– Resistant varieties

Materials and Methods

In-vitro screening

• The inoculum of B. sorokiniana raised from single spore culture of the most aggressive isolate on PDA.

• Seeds of sixty nine commercial varieties (2008-09)& seventy one (during 2009-10) were tested by cotton swab method (Iftikhar et al., 2008)

• By using 5 mm of inoculum disc containing 3.2 x 104.spores/ disc .

• Aafter inoculation, tubes incubated in growth chamber at 25oC for 25-28 days.

• 0-5 scale:

• 0 = no symptoms• 1 = 1-5 % spots on leaves• 2 = 6-20 % spots on leaves• 3 = 21 – 40 % spots on leaves• 4 = 41 - 60 % spots on leaves• 5 = more than 60 %

– (IRRI, 1996).

Data classified into following categories: 0= resistant (R)1-2 = moderately resistant (MR)3-4 = moderately susceptible (MS)5= susceptible (S)

In-vivo screening• Seventy two commercial wheat varieties (2008-09) and

(2009-10) were screened in the field of NARC, Islamabad by

artificial inoculations.

• Material was planted in randomized block design manner with 1m row having 30 cm row to row distance.

• Three to four days before head initiation inoculum (3.4 x 10 4 conidia/ ml) was sprayed thoroughly by automizer on each variety.

• Irrigated just after inoculation.

• At maturity data was recorded on double digit scale (0-9).

Rating scale

• 0-9 double digit scale :– 0=No disease---HR– 1-2= 1-10%----R– 3-5= 11-30------MR– 6-7=31-40%----MS– 8=41-50%-------S– 9=Above 50%---HS

Results

S.No. Cultivars In-vitro(0-5)

categories

Cultivars In-vitro(0-5)

categories

1 Bakhtawar 92 4 MS Bakhtawar 92 4 MS

2. Blue silver 5 S Blue silver 2 MR

3. Chakwal 86 2 MR Chakwal 86 2 MR

4. Sind-81 3 MR Sind-81 3 MR

5. Zarghoon 4 MS Zarghoon 4 MS

6. Faisalabad 83 4 MS Faisalabad 83 5 S

7. Faisalabad 85 3 MR Faisalabad 85 4 MS

8. Inqilab 91 2 MR Inqilab 91 3 MR

9. Kaghan 93 3 MR Kaghan 93 3 MR

10. Kirin 95 4 MS Kirin 95 3 MR

11. Kohinoor 83 5 S Kohinoor 83 3 MR

12. LU-26 4 MS LU-26 2 MR

13. Nowshera 96 4 MS Nowshera 96 3 MR

14. Parwaz 94 3 MR Parwaz 94 4 MS

15. Pasban 90 3 MR Pasban 90 5 S

16. Mexipak 65 4 MS Mexipak 65 3 MR

17. Punjab 96 3 MR Punjab 96 4 MS

18. Sariab-92 5 S Sariab-92 4 MS

19. Sarsabz 4 MS Sarsabz 4 MS

20. Shaheen 94 4 MS Shaheen 94 5 S

21. Shahkar 95 3 MR Shahkar 95 4 MS

22. Soughat 90 5 S Soughat 90 4 MS

23. Tandojam 83 1 R Tandojam 83 3 MR

24. SH-2002 3 MR SH-2002 4 MS

25. Pak 81 3 MR Pak 81 5 S

26. Bahawalpur-97 1 R Bahawalpur-97 3 MR

27. MH-97 2 MR MH-97 5 S

28. Kohistan 97 3 MR Kohistan 97 3 MR

29. Kohsar 95 5 S Kohsar 95 2 MR

30.. Rohtas 90 3 MR Rohtas 90 3 MR

31. Suleman 96 4 MS Suleman 96 5 S

32. WL 711 2 MR WL 711 5 S

33. Zardana 3 MR Zardana 5 S

34. Abadgar 93 4 MS Abadgar 93 5 S

35. Anmol-91 2 MR Anmol-91 5 S

36. Bahawalpur-2000 3 MR Bahawalpur-2000 5 S

36. Bahkhar-2002 3 MR Bahkhar-2002 5 S

38 Fakhr-e-Sarhad 2 MR Fakhr-e-Sarhad 4 MS

39. Marvi-2000 4 MS Marvi-2000 2 MR

40. Mehran-89 5 S Mehran-89 5 S

41. Takbeer 2 MR Takbeer 1 R

42. AS-2002 3 MR AS-2002 3 MR

43. Iqbal 2000 4 MS Iqbal 2000 3 MR

44. Auqab-2000 3 MR Auqab-2000 5 S

45. Chakwal-97 4 MS Chakwal-97 3 MR

46. Durum-97 4 MS Durum-97 3 MR

47. Watan 94 5 S Watan 94 4 MS

48. Moomal 2002 4 MS Moomal 2002 3 MR

59. Zarlashata 4 MS Zarlashata 4 MS

50. GA-2002 4 M4 GA-2002 4 MS

51. Wafaq-01 3 MR Wafaq-01 4 MS

52. Magalla-99 4 MS Magalla-99 5 S

53. Manthar-3 4 MS Manthar-3 5 S

54. Saleem 2000 3 MR Saleem 2000 5 S

55. Khyber 87 3 MR Khyber 87 4 MS

56. Pirsabak 2004 4 MS Pirsabak 2004 5 S

57. Pirsabak 2005 3 MR Pirsabak 2005 3 MR

58. Punjnad-1 4 MS Punjnad-1 4 MS

59. Darawar-97 4 MS Darawar-97 4 MS

60. V-87094 3 MR V-87094 3 MR

61. Shafaq 2006 3 MR Shafaq 2006 4 MS

62. Sehar 2006 4 MS Sehar 2006 4 MS

63. Bhittai 3 MR Bhittai 4 MS

64. Chakwal-50 4 MS Chakwal-50 5 S

65. Saussi 3 R Saussi 2 MR

66. Lasani-08 3 MR Lasani-08 3 MR

67. Meraj-08 4 MS Meraj-08 4 MS

68. Fareed-06 3 MR Fareed-06 5 S

69. Faisalabad-08 3 MR Faisalabad-08 4 MS

70. Rashkoh-2005 5 S

71. Bathoor 5 S

IN VIVO

S.No. Cultivars In-vIVO

categories

Cultivars In-vIVO

categories

1 Bakhtawar 92 10% R Bakhtawar 92 7% R

2. Blue silver 1% R Blue silver 7% R

3. Chakwal 86 37% MS Chakwal 86 11% MR

4. Sind-81 7% R Sind-81 5% R

5. Zarghoon 22% MR Zarghoon 7% R

6. Faisalabad 83 2% R Faisalabad 83 15% MR

7. Faisalabad 85 22% MR Faisalabad 85 37% MS

8. Inqilab 91 10% R Inqilab 91 11% MR

9. Kaghan 93 7% R Kaghan 93 7% R

10. Kirin 95 5% R Kirin 95 11% MR

11. Kohinoor 83 5% R Kohinoor 83 15% MR

12. LU-26 2% R LU-26 25% MR

13. Nowshera 96 2% R Nowshera 96 25% MR

14. Parwaz 94 5% R Parwaz 94 25% MR

15. Pasban 90 2% R Pasban 90 15% MR

16. Mexipak 65 15% MR Mexipak 65 11% MR

17. Punjab 96 19% MR Punjab 96 15% MR

18. Sariab-92 4% R Sariab-92 7% R

19. Sarsabz 12% MR Sarsabz 15% MR

20. Shaheen 94 10% R Shaheen 94 1% R

21. Shahkar 95 10% R Shahkar 95 5% R

22. Soughat 90 2% R Soughat 90 22% MR

23. Tandojam 83 1% R Tandojam 83 15% MR

24. SH-2002 7% R SH-2002 15% MR

25. Pak 81 15% MR Pak 81 5% R

26. Bahawalpur-97 5% R Bahawalpur-97 5% R

27. MH-97 19% MR MH-97 11% MR

28. Kohistan 97 4% R Kohistan 97 1% R

29. Kohsar 95 2% R Kohsar 95 7% R

30. Rohtas 90 1% R Rohtas 90 15% MR

31. Suleman 96 15% MR Suleman 96 11% MR

32. WL 711 4% R WL 711 11 MR

33. Zardana 5% R Zardana 5% R

34. Abadgar 93 1% R Abadgar 93 11% MR

35. Anmol-91 19% MR Anmol-91 5% R

36. Bahawalpur-2000 15% MR Bahawalpur-2000 37% MS

36. Bahkhar-2002 4% R Bahkhar-2002 19% MR

38 Fakhr-e-Sarhad 5% R Fakhr-e-Sarhad 7% R

39. Marvi-2000 4% R Marvi-2000 79% S

40. Mehran-89 2% R Mehran-89 15% MR

41. Tatara 6% R Tatara 20% MR

42. Takbeer 7% R Takbeer 15% MR

43. AS-2002 5% R AS-2002 S% R

44. Iqbal 2000 26% MR Iqbal 2000 15% MR

45. Auqab-2000 5% R Auqab-2000 7% R

46. Chakwal-97 1% R Chakwal-97 5% R

47. Durum-97 5% R Durum-97 15% MR

48. Watan 94 1% R Watan 94 20% MR

49. Moomal 2002 1% R Moomal 2002 22% MR

50. Zarlashata 19% MR Zarlashata 5% R

51. GA-2002 19% MR GA-2002 2% R

52. Wafaq-01 7% R Wafaq-01 10% R

53. Magalla-99 2% R Magalla-99 22% MR

54. Manthar-3 5% R Manthar-3 7% R

55. Saleem 2000 22% MR Saleem 2000 10% R

56. Khyber 87 2% R Khyber 87 15% MR

57. Pirsabak 2004 10% R Pirsabak 2004 7% R

58. Pirsabak 2005 5% R Pirsabak 2005 7% R

59. Punjnad-1 2% R Punjnad-1 5% R

60. Darawar-97 2% R Darawar-97 11% MR

61. V-87094 2% R V-87094 7% R

62. Shafaq 2006 1% R Shafaq 2006 15% MR

63. Sehar 2006 2% R Sehar 2006 2% R

64. Bhittai 2% R Bhittai ……

65. Chakwal-50 5% R Chakwal-50 7% R

66. Saussi 1% R Saussi 7% R

66. Lasani-08 10% R Lasani-08 15% MR

68. Meraj-08 2% R Meraj-08 30% MR

69. Fareed-06 12% MR Fareed-06 15% MR

70. Faisalabad-08 10% R Faisalabad-08 15% MR

71. Rashkoh-2005 10% R Rashkoh-2005 7% R

72. Bathoor 12% MR

• 2008-09• In-Vitro in-VivoOut of 69 Comm. Var. Out of 71 Comm. Var.

– Resistant---2 Resistant—55– Moderate Resistant—34 Moderate Resistant—15 – Moderate Susceptible—26 Moderate Susceptible-1

– Susceptible---7

• 2009-10• In-Vitro in-Vivo• Out of 71 Comm.Var. Out of 72 Comm. Var.

– Resistant—1 Resistant—32– Moderate Resistant—25 Moderate Resistant—37– Moderate Susceptible—23 Moderate Susceptible—2– Susceptible—22 Susceptible--1

The data shows the adult plant resistance.

CONCLUSION

• 2 years study under controlled and fieldconditions, ten varieties including Chakwal 86,Zarghoon, Tandojam83, Bahawalpure 97,Kohistan 97, Rohtas 90, Takbeer, AS 2002,Auqab and Saussi may be recommended forfurther exploitation as having moderateresistance at seedling stage(controlledconditions) and adult plant resistance under fieldconditions.