Physiology of Growth and Reproduction in Rice. II. Effect of Plant Growth Substances on Three Winter Varieties.

Abstract

The effects of auxins on whole plants have been studied by many workers. Cereals (1,2,6,8,25,26) have been frequently used in such investigations.The recent reviews by Lang (7) and Liverman (11) bring out interesting relationships between the auxin response and the photoperiodic nature of the experimental plant. Auxins frequently promote flowerinig in long-day plants but seldom in short-day species (8,27 made each day at about 9 A.M. The data as a whole show that IAA at 250 and 100 ppm, and TIBA at all concentrations, brought about a significantly earlier ear emergence than in the controls. However, there is a marked difference among the varieties in the response to the same growth substance. The auxin IAA had no effect on ear emergence in the earlywinter and mid-winter varieties but produced a significant earliness in the late-winter variety at the concentrations of 250 and 500 ppm. The other auxin, NAA, brought about a significant delay in ear emergence in the early-winter variety at higher con-

Yield and Biochemical Attributes of Brri Dhan-44 (Oryza Sativa L.) as Affected by Tiba Application

“…Munira (2015) reported that 1000-grain weight increased following all concentration of TIBA treatments in BARI Maize-6 where, significantly highest value was obtained from 25 ppm treated plants. However, findings of Misra and Sahu (1958) did not observe any significant effect of TIBA on 1000-grain weight of rice. Similar results of increases in seed weights following TIBA application were also reported by other investigators (Ravichandran andRamaswami 1991, Jahan andKhan 2014).…”

“…Increases in length of pods due to TIBA application were reported by Munira (2015) in BARI Maize-6 and Adam and Jahan (2014) in BARI Mung-5. However, Misra and Sahu (1958) did not find any significant changes due to TIBA application on rice plant.…”

“…Results revealed that number of grains per panicle of BRRI dhan-44 responded positively following all treatments and increased significantly due to 10 and 100 ppm treatments. Misra and Sahu (1958) obtained increased number of grains per panicle from 100 ppm TIBA treated rice plant. Number of karnels per cob increased following TIBA application in BARI Maize-6 (Munira 2015).…”

“…Application of TIBA had also beneficial effect on per cent of un-filled grains per panicle with an exception of 100 ppm treatment. By applying different concentration of TIBA, Misra and Sahu (1958) found increased percentage of grain setting where, variation was significant due to 100 ppm treatment.…”

“…Whereas, in case of non-effective tillers per plant better response was obtained from 50 and 100 ppm TIBA treatments. Reports of Misra and Sahu (1958) revealed that the number of panicles per plant was increased due to 250 and 500 ppm TIBA application. Similar results of increase were also recorded in other plants by several investigators (Chung and Kim 1989, Ravichandran and Ramaswami 1991, Rahman and Rahman 1997, Mondal and Dutta 2002, Djanaguiraman et al 2005.…”