http://ir.lib.ruh.ac.lk/handle/iruor/19201 2026-04-26T17:09:26Z 2026-04-26T17:09:26Z Ranawake, A.L. Dahanayaka, N. Amarasingha, U.G.S. Rodrigo, W.D.R.J. Rodrigo, U.T.D. http://ir.lib.ruh.ac.lk/handle/iruor/19560 2025-06-17T08:39:35Z 2011-09-07T00:00:00Z

Effect of water stress on growth and yield of mung bean (vigna radiata l) Ranawake, A.L.; Dahanayaka, N.; Amarasingha, U.G.S.; Rodrigo, W.D.R.J.; Rodrigo, U.T.D. Legumes are second only to the Graminae in their importance to humans. Mung bean (Vigna radiata L) is one of the most important grain legumes cultivated in Sri Lanka. Drought is a major abiotic stress on Mung bean in the sub-humid, dry and intermediate zones of Sri Lanka. The present study reveals the response of Mung bean for the water stress at three different growth stages; three weeks after planting (3 WAP), six weeks after planting (6 WAP) and eight weeks after planting (8 WAP). A pot experiment was carried out at Faculty of Agriculture, University of Ruhuna, Mapalana, Sri Lanka. Plant height, number of leaves, number of floral buds, dry matter weight of shoot system, number of lateral roots, length of tap root, number of root nodules, and dry matter weight of root system were measured after one week recovery period in 10 day drought stressed plants at three different growth stages and in rele vant control plants. Water stress significantly affects on each of the measured parameters at 6 WAP, the flowering and pod filling stage of Mung bean. Only number of leaves was significantly affected when the drought applied at 8 WAP. Further, all the measured parameters other than length of tap root and number of nodules per plant were significantly affected by drought stress at 3 WAP. Number of floral buds and number of pods were not affected by the drought stress at 8 WAP though there is no economical value of these characters as the pod filling efficiency is low in Mung bean under drought stress.

2011-09-07T00:00:00Z Swathi Lekshmi, P.S. Balasubramani, N. Chandrakandan, K. http://ir.lib.ruh.ac.lk/handle/iruor/19528 2025-06-16T10:39:53Z 2011-09-28T00:00:00Z

Diffusion of scientific shrimp farming through various stages of the adoption period Swathi Lekshmi, P.S.; Balasubramani, N.; Chandrakandan, K. Commercial shrimp culture has become to the mainstay of the coastal economy of India. The present study was undertaken among 120 shrimp farmers from the two predominant shrimp farming districts of the country. The aim of the study was to find out the various stages of diffusion of scientific shrimp farming through various stages of the adoption from 1997-2003, as well as to study the present adoption behavior of the shrimp farmers. Using a structured interview schedule each of the respondent was interviewed to know his stage of adoption of scientific shrimp farming in each of the year ranging from 1997 to 2003. The number of respondents in each stage of adoption in each of these years was worked out and expressed as percentages. The present adoption behaviour of the shrimp farmers was studied using the adoption quotient formula. The study revealed that the symbolic adoption and use adoption was high in the years 2002 and 2003 when more of the critical technologies of health and water management were developed and transferred to the target population. Practice wise adoption of the technologies revealed that the adoption behaviour was high in harvesting, pond bottom conditioning, pond bottom sterilization, liming of pond and feed management.

2011-09-28T00:00:00Z Hossain, M.F. Ara, N. Uddin, M.R. Dey, S. Islam, M.R. http://ir.lib.ruh.ac.lk/handle/iruor/19527 2025-06-16T09:29:03Z 2011-10-14T00:00:00Z

Effect of time of sowing and plant spacing on broccoli production Hossain, M.F.; Ara, N.; Uddin, M.R.; Dey, S.; Islam, M.R. A field experiment was conducted at Agricultural Research Station, BARI, Thakurgaon during rabi season, 2009/10 to find out the optimum time of sowing and plant spacing on broccoli production. Three sowing time viz. (i) 1 October, (ii) 15 October and (iii) 30 October and three plant spacing viz. (i) 60 x 40cm, (ii) 60 x 50cm and (iii) 60 x 60cm were included in the study. Yield and yield contributing characters were significantly influenced by the treatments. 1 October sowing produced the highest yield (21.39 t/ha) and 30 October sowing produced the lowest yield (13.6t/ha) of broccoli. On the other hand, closer spacing (60 x 40cm) produced the highest yield (18.8t/ha) which was statistically similar to 60 x 50cm (17.6t/ha) and lowest yield (16t/ha) was obtained from 60 x 60 cm spacing. 1 October sowing and 60 x 40cm plant spacing combination produced the highest yield (22.5t/ha) which was statistically similar to 1 October sowing and 60 x 50cm plant spacing (21.9t/ha) and the lowest yield (12.8t/ha) was produced from 30 October sowing and 60 x 60cm plant spacing combination.

2011-10-14T00:00:00Z Dahanayake, N. Ranawake, A.L. http://ir.lib.ruh.ac.lk/handle/iruor/19523 2025-06-16T07:10:25Z 2011-10-06T00:00:00Z

Regeneration of dragon fruit (hylecereus undatus) plant lets from leaf and stem explants Dahanayake, N.; Ranawake, A.L. Dragon fruit (Hylocereus undatus) (Cactacea) is a climbing vine which has received worldwide attention, first, as an ornamental plant and then extended as a fruit crop. Since seed viability of stored dragon fruit is very low, stem cuttings are used as planting material in Dragon fruit. Though several studies have examined different propagation methods for Dragon fruit; very little information is available on protocols for production of high quality planting material via tissue culture. In the present study we examined the potential of direct shoot regeneration of Dragon fruit explants using leaf and stem cuttings obtained from in vitro germinated seedlings in 3 different concentrations of Benzylaminopurine (BA) 2, 2.5, 3mg/l supplemented with 0.01mg/l NAA to the Murrashige and Skoog (MS) basal regeneration medium. Thereafter regenerated plantlets from direct organogenesis from all explants were rooted in MS basal medium supplemented with 0.01mg/l NAA (Naphthaleneacetic acid). Results revealed that the type of explants greatly influences the regeneration ability of shoot buds. Stem explants exhibited much higher regeneration ability (18 buds/explant) than leaf explants (3 buds/ explant) without vitrification. Within 4 weeks, buds were initiated on explants on MS basal medium supplemented with 2.5mg/l BA and 0.01mg/l NAA and buds took nearly 60 days to elongate to 1.5cm on the same medium. Stem and leaf explants, regenerated the highest number of shoots on MS medium supplemented with 2.5mg/l BA and 0.01 NAAmg/l compare to that of the other hormone combinations. Rooting was observed in regenerated mature shoots after transferred onto MS basal medium with 0.01mg/l NAA.

2011-10-06T00:00:00Z