EFFECT OF DIFFERENT LEVELS OF LIGHT INTENSITY ON MORPHOPHYSIOLOGY AND YIELD OF BRINJAL (Solanum melongena L.)

Abstract

ABSTRACT Low light stress is a limiting factor for crop production especially in agroforestry system. A pot experiment was conducted in the Field Laboratory of the Department of Agroforestry and Environmental Science, Sher-e-Bangla Agricultural University, Dhaka- 1207, during the months of October 2019 to mid April 2020. Three brinjal varieties viz. V1 (BARI Begun-1), V2 (BARI Begun-4), V3 (BARI Begun-9) were exposed to four light intensity treatments, (100, 75, 50 and 25% PAR which indicate control (S0), S1, S2 and S3, respectively) to evaluate their performances. Light stress (mainly S2 and S3) substantially hampered the plant growth, development as well as yield. Low light stress primarily reduced the photosynthetic performance (lower SPAD value) of plants which contribute in reduction of plant height, number of primary branches and leaves of all brinjal plants. Moreover low light intensity negatively affects the fresh and dry weight. It can also decrease number of fruits, fruit length, fruit diameter and individual fruit weight in all variety. As a result plant wise brinjal production hampered seriously with low yield. In comparison with control (100% PAR) treatment, 75% PAR condition (S1) decreased fruit weight by 16.8, 13.5 and 19.7% in V1, V2 and V3, respectively. In 50% PAR condition, yield per plant were decreased by 36.4, 33.5 and 42.4% in V1, V2 and V3, respectively. Lastly severe stress (S3) declined fruit weight per plant by 55.0, 61.5 and 67.0% in V1, V2 and V3, respectively. From this result it is very clear that under severe stress (S3) V1 cultivar perform well but V2 perform well against S1 and S2 treatments. But before suggesting variety for any agroforestry system more research work should be performed in different soil condition.