MORPHO-PHYSIOLOGICAL CHARACTERISTICS AND YIELD OF THREE AROMATIC RICE CULTIVARS UNDER DIFFERENT LEVELS OF 6-BAP

Abstract

A field experiment was conducted to study the effect of 6-Benzyl aminopurine (6-BAP) on morpho-physiological, yield and yield characters of three aromatic rice varieties cv. Chinigura (V1), Kataribhog (V2) and Kalijira (V3). The 6-BAP was sprayed 0, 20, 40, 60 and 80 ppm at vegetative and pre flowering stages. Results showed that the morphophysiological, yield and yield attributes were significantly different among the varieties studied under the application of different levels of 6-BAP. There was a significant relationship among the varieties and different levels of 6-BAP on both vegetative and harvesting stages regarding tillers hill-1 . A statistically significant variaties was observed in plant length, root depth, panicle length, effective and non-effective tiller, grain yield, biological yield, harvesting index, chlorophyll-a, total chlorophyll content, and poline content except straw yield and 1000 grain weight. Among three varieties, Kataribhog had more yielding ability by using 60 ppm T4 6-BAP than those of chinigura and kalijira. The highest plant height (172.9 cm) was found in V1 variety using 60 ppm of 6-BAP. The highest panicle length was in V1 variety using 40 ppm of 6-BAP and the lowest was found in V2 variety under control treatment. The maximum amount of grain per panicle (287.00) was found in V2 variety in the treatment T4 (60 ppm) and (241.1) was the lowest value which was found in V1 variety in the control T1 treatment. The maximum amount of chlorophyll-a (24.59 mg g-1) found at V1×T4 and the lowest amount of chlorophyll a (14.87 mg g-1 ) showed by the treatment V2 × T2. The highest amount of total chlorophyll content (25.95 mg g-1 ) was in V1×T4 treatments while the lowest amount (18.35 mg g-1 ) was at V3×T5 treatments. The highest proline content (0.35 mg g1 ) was recorded in V1×T2 and the lowest proline content (0.26 mg g-1 ) was recorded in V2×T4. Some yield contributing characters of aromatic rice such as grain number per panicle, grain weight per panicle and total grain yield were influenced due to the interaction effect of variety and levels of 6-BAP. The spraying with 60 ppm 6-BAP had the better stimulation on growth on yield of Kataribhog and Kalijira but 80 ppm for Chinigura. The highest yield was in Kataribhog rice variety (1.66 t ha-1 ) spraying 60 ppm 6-BAP twice at vegetative and preflowering stages. Plant growth regulators promote the growth and yield of aromatic rice varieties which might be an alternative eco-friendly tool for rice production. Out of the three rice varieties Kataribhog performed better considering growth and yield parameters.