Effect of sulphur dioxide on growth and nodulation of pigeonpea

Effect of sulphur dioxide on the growth of pigeonpea (Cajanus cajan (L.) Millsp.) was studied. Five day old pigeonpea seedlings were exposed to 10 and 20 ppm SO2 in glass chambers for 3 hr/day continuously for two weeks. Analyses were made in 25-day old seedlings with respect to foliar injury, morphological characteristics, dry matter accumulation and nodule number. Sulphur dioxide affected leaves showed chlorosis, tip burn and marginal necrosis. Root growth and nodulation were very much reduced in fumigated seedlings. Sulphur dioxide exposure decreased dry matter accumulation in all the parts of the seedling.