Effects of Leaf Age and Inoculum Concentration on Resistance of Detached Chickpea Leaflets to Two Different Races of Ascochyta rabiei Pass. Labr.

Abstract

The effects of leaf age and inoculum concentration on resistance of chickpea cultivars to Ascochyta rabiei Pass. Labr. were studied using a detached leaflet method. Young and old leaflets of 30 day-old plant of two chickpea cultivars ILC 195 and Can ı tez 87 were inoculated with each of six different inoculum concentrations 4, 8 ,16, 32, 64 and 128x10 4spores/ml of race 1 and 4 of Ascochyta rabiei. Disease reactions were assessed 3, 5, 7, 9, 11 and 13 days after inoculation. The appearance of lesions on leaflets depended on race and leaflet age. Disease severity increased with increasing inoculum concentration from 4x10 4to 128x104 , but this increase depended on the chickpea cultivar, leaflet age and race of Ascochyta rabiei. Young leaflets of both cultivars inoculated with race 1 did not produce lesions at low inoculum concentrations 4 and 8x10 4 ' spores/ml . Young leaflets of cv. ILC 195 were found to be moderateiy resistant to race 1; however, young leaflets of cv. Can ı tez 87 were susceptible to'race 1. The young leaflets of cv. ILC 195 were more resistant to race 4 than cv. Can ı tez 87. Disease severity in ,young l

Keywords

• Chickpea, Ascochyta rabiei, inoculum concentration, leaf age.

Koparı lmış Nohut Yapraklar ı n ı n Ascochyta rabiei Pass. Labr.'nin Farkl ı iki Irk ı na Dayanı kl ı l ığı nda İ nokulum Yoğ unlu ğ u ve Yaprak Ya şı n ı n Etkisi

Abstract

Ascochyta rabie ı'ye karşı nohut çe ş itlerinin gösterdikleri dayan ı kl ı l ı kta yaprak ya şı n ı n ve inokulum yoğ unluğ unun etkisi, kopar ı lm ış yaprak metodu kullan ı larak saptanm ış t ı r. Iki nohut ILC 195 ve Can ı tez 87 çeş idinin 30 günlük bitkilerinin genç ve ya ş l ı yapraklar ı Ascochyta rabiei'nin 1 ve 4 nolu ı rklar ı n ı n 6 4, 8, 16, 32, 64 ve 128x104spor/mi farkl ı yoğ unluktaki spor süspansiyonlar ı ile inokule edilmi ş lerdir. Hastal ı k reaksiyonlar ı inokulasyondan 3, 5, 7, 9, 11 ve 13 gün sonra de ğ erlendirilmi ştir. Yapraklar üzerinde lezyonlar ı n meydana geldi ğ i günler yaprak ya şı na ve ı rka ba ğ l ı olarak değ i ş mi ştir. Inokulum yoğ unluğ u 4x104den 128x104 'e do ğ ru artt ı kça hastal ı k şiddeti de artm ış t ı r. Ancak bu art ış nohut çeş idine, yaprak ya şı na ve Ascochyta rabielnin Irklar ı na bağ l ı olarak değ i ş mektedir. Irk 1'in dü ş ük inokulum konsantrasyonu 4 ve 8x10 4spor/mi ile inokule edilen her iki çe ş idin genç yapraklar ı nda lezyon meydana gelmemi ştir. ILC 195 çeş idinin genç yapraklar ı ı rk l'e orta derecede dayan ı kl ı , buna karşı n Can ı tez 87 çeş idinin genç yapraklar ı ayn ı ı rka duyarl ı olarak bulunmu şlard ı r. ILC 195 çeş idinin genç yapraklar ı Can ı tez 87 çeş idine k ı yasla ı rk 4'e dayan ı kl ı d ı r. Ascochyta rabiei nin her iki ı rk ı ile inokule edilen her iki çeş idin genç yapraklar ı ndaki hastal ı k ş iddeti ya ş l ı yapraklardakilerden çok daha dü ş üktür.

Keywords

• Nohut, Ascochyta rabiei, inokulum yoğunluğu, yaprak yaşı

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