A Report on Direct Seeded Rice Technique

2012 Institute of Agriculture and Animal Science

A Research Report on

PERFORMANCE OF DIFFERENT RICE

VARIETIES UNDER DIRECT SEEDED

RICE TECHNIQUE AT INNER TERAI

REGION OF NEPAL

Submitted By:

Babu Ram Panthi

B.S. (Agriculture)

[email protected]

1. INTRODUCTION

Agriculture contributes with 32.12% to the total Gross Domestic Product (GDP) of Nepal and rice is the most important crops, which alone contributes with 19.75% to the agricultural GDP (MOAC, 2010). Rice (Oryzasativa L.) is the most preferred food crops of Nepal and is consumed 262 gm/capita daily which fulfills more than 50% of the calorie requirement of Nepalese populations ( Knnedy et al., 2002). Rice ranks first in terns o area and production accounting for 58% of the total grain production and about 46% of the total agricultural area (Sah and Sah, 2004). Basnet (2008) reported that the rice crop was grown in 1.55 million hectare producing 4.3 million mt and the productivity was 2.775 t/ha. Similarly, NARC (2008) reported that rice covers 1.56 million hectare of the total cultivated area with productivity of 2.85 t/ha. In spite of the position of rice in Nepalese agriculture food scenario, productivity of this crops remains very low (2.55 mt/ha), which is far below than that of other rice cultivating countries, like Egypt (9.97 mt/ha), Australia (8.15 mt/ha), South China (6.34 mt/ha) and Korea (6.27mt/ha) (FAOSTAT, 2005).

Rice s grown in all three ecological zones of the country. The terai region (60-900 masl) contains nearly 73% of area and provides 75% of the total production. Hills (900- 1500 masl) and mountains (1500- 2300 masl) have 24% and 3% of the total rice producing 23% and 2% of rice grains respectively (Bhandari, 2004). As rice is grown under diverse soil and climate conditions, the growth in rice production is low (grain yield 2.07% per annum), compared to the rate of population growth (2.2% per annum) (Adhikari, 2004). Thus, Nepal has become a net rice importing country with import worth 71 crore rupee from India during 2002/03) MOAC, 2004). Estimates indicate that the rate of increase in rice production has been slowed down to a point where it is below the rate of rice consumers. So rice production need to be increased much more than the present amount. No new area can be used for rice farming. Good ride land in peri - urban areas is fast declining due to raped urbanization and industrialization. Productivity increment is the only way to increase the production (NARC, 2008). Rice production must increase from 500 to 800 million ton in the next 25 years to meet projected world rice demand (Balasubramanian et al., 2000).

Traditionally rice is frown by transplanting with one month old seedlings into the puddle and flooded soil condition. Puddling is done to create a hard pan below the plough zone for reducing soil permeability. This increases the cost of cultivation (Giri, 1996) with potential loss in farm income (Tripathi et al., 2004). In this system, high losses of water occur in the puddling process through surface evaporation and percolation. Recently,it has realized that this method degrades natural resources like soil and water due to its continuous use in spite of higher yield (Hobbs, 2003). It is estimated that world’s per capita availability of water, about 85% if which is used in agriculture, has declined by 60% from 1950 to 1990 (Balasubramanian et al., 2000). A water crisis for rice farming is fast approaching. India, Pakistan and Philippine are particularly expected to suffer a sharp decline in per capita water availability over the next two decades. Rice production systems are rapidly changing due to the declining availability of water resources for agriculture. There is not appropriate rice crop establishment technology for such areas where water is declining and being scarce resources. The water use efficiency of rice is much lower than that of other crops. On an average more than 5000 liters of water are used to produce 1 kg of rice ( Balasubramanian et al., 2000), 30% of which is used alone in puddlng operation. It is predicted that 17 million ha of irrigated rice areas may experience physical water scarcity and 22

million ha may have economic water scarcity by 2025 in Asia(Bouman and Tuong, 2001). Thus, water scarcity threaten the sustainability of irrigated rice ecosystems since it may no longer be feasible for farmer to undertake wet cultivation and flood field to ensure good crop establishment and control weeds ( Johnson and Mortimer, 2005). The labor requirement for establishing a transplanted rice (nursery and transplanting) each approximately 50 person days/ha in comparism to 3-7 person day/ha for drill or wet seeded rice (FAO, 2010). Thus increasing scarcity of labor and too much competition for irrigation, tillage and other resources during transplanting of rice have put a lot of burden to the rice growers (Tripathi et al., 2000; 2002).

Growing rice under aerobic environment can reduce water consumption and losses to a greater extent. Therefore, it is suggested that alternate method of planting viz., direct seeding should be adopted instead of the conventional transplanting to reduce the water and labor demand, which is ultimately reduce the cost of production (Mann et al., 2007). Tripathi et al., 2004 reported that with the development of recourses conserving technologies, direct seeding of ride has emerged as viable alternate to transplanting. Direct seeding rice avoids the puddling but maintains continuous moist soil condition and thus reduces the overall water demand for rice culture. In South Asia, direct seeded rice is being practiced for long time on terraced and sloppy lands of Bangladesh, along the coast and Western Himalayan region of India (Gupta et al., 2006). In order to save water and labor and promote conservation agriculture, with no/reduced tillage, it is absolutely essential to replace puddle transplanting with direct seeding. Recently, DSR is being practiced increasingly to cope with the reduced availability of irrigation water. DSR facilitates timely establishment of rice and succeeding winter crops as DSR rice matures earlier than transplanted rice by 1-2 weeks (Yadav, 2006).

The main problem regarding the farming of DSR is the weed infestation and the scares of suitable variety for the specific agro climatic region.in transplanting system of rice cropping various varieties have been released and several research have been carried out to select the suitable varieties performing best in the specific site. Regarding the DSR technique of rice farming the research on weed management has been on carried out and several recommendations have been made based 0n research. But the research on selection of variety performing well on DSR technique of rice farming has not been performed. Therefore, this research have been designed to address the problems of making DSR more popular among the farmers with the following objectives

• To compare the performance of different rice varieties under DSR technique of rice farming.

• To make the recommendation of the suitable varieties performing well in inner terai.

2. Literature review

Direct Seeded Rice (DSR)

Direct seeding is the sowing of rice under aerobic environment which avoids the puddling but maintains continuous moist soil conditions and thus reduces the overall water demand for rice culture. Dry seeding of rice (Oryza sativa L.) involves a major change in the production practices for attaining optimal plant density and high productivity in the water deficit areas of the Pakistan( Mann et al., 2007). Direct seeding, which does not require seedlings to be raised or transplanted, is regarded as the most effective method of reducing cost and labor. IRRI (2007) found that DSR can produce similar or higher yields than transplanted crops. It also facilitates timely establishment of rice and succeeding crops as crop matures 10- 15 days earlier. Earlier planted DSR matures 1-2 wks before transplanted rice, thus reducing the risk of terminal drought and allowing earlier planting of a following non rice crop (Salehet al.2000). It not only reduces the delayed sowing of wheat but also saves irrigation given for the seed bed preparation, cost of preparatory tillage and increasing wheat yield due to its earlier planting. According to the observations at field conducted by the Directorate of on Farm Water Management (OFWM), Punjab, which introduced zero tillage in the country, it saves irrigation water by 20 percent and increases wheat yield 15-20 percent (Khan, 2007).

Recent developments in rice production technology as well as new economic trends are encouraging farmers to shift from traditional transplanting to direct seeding. Direct seeding is already the dominant sowing method used by farmers in Srilanka and Malaysia. Its importance as a leading method of crop establishment has also increased during the past three decades in the Philippines, Thailand, and the Mekong Delta in Vietnam (IRRI, 2000). Area under DSR is in increasing trend and has reached to 26 percent of the total rice area in South-East Asia (Khan, 2007).

Rice can be directly seeded either dry or wet (pre germinated) seeding. Dry seeding of rice can be done by drilling the seed into the fine seedbed at a depth of 2-3cm.(Kumar, 2009). Pandey and Velasco (1998) considering water availability and opportunity cost of labor have hypothesized that dry seeding of rice is an appropriate alternative for South Asia. Direct seeded rice reduces the climatic risk caused by unpredictable monsoon rains reducing dependence on pump sets and tractors for timely crop establishment will benefit poorer farmer.

Direct seeding of rice is receiving great attention in Korea because of its low-input nature (Kim and Shin, 2007). Kumar (2009) reported that it saves water by 35-40%, reduces production cost by Rs.3000/ha, and increases yield by 10%. Water and land resources are under pressure in Asia as urban and industrial sectors expand (Nguyen and Ferrero, 2004). In the Philippines, there is only enough water to grow rice on half of the irrigated area during the dry season (IRRI, 2001). Direct seeding is perceived as a water saving technology with a potential to use less water than transplanted rice (Pandey and Velasco, 2002). Direct drill seeded rice is emerging as resource

conserving technology with reduced or no tillage saves water, labor, fuel and time without yield penalty and thus gives higher return compared to the conventional transplanted rice (CT-TPR). It also maintains soil health and improves fertilizer use efficiency and is more adaptive to drought (Singh et al., 2008). The labor is also less in DSR as compared to TPR. Net labor savings with DSR compared with transplanting rice (TPR) averaged 27 days/ha.

Direct seeded rice was privately profitable for farmers, giving net returns of Rs.13, 350 per ha for dry direct seeded and Rs.11, 592 per ha for transplanted rice (Yadav et al., 2005). In 2004, for the fourth successive year, at Pantnagar wet direct seeded rice gave the greatest yield: 7.1 versus 6.8 t/ha for transplanted and 5.9 t/ha for dry direct seeded (Yadav et al., 2005).

Higher rate of methane emission was observed in CT-TPR compared to DSR. Methane emission mitigation, ranged from 18% in TPR to 85% in DSR+ sesbania (Gupta et al., 2008). Lower methane emission in DSR was due to alternate wetting and drying of field whereas in CT-TPR the field was continuously submerged for the entire period of rice growth. The DSR used 55% less irrigation water with 22% reduction in grain yield compared to TPR. Irrigation water productivity was 42% less in TPR as compared to DSR (Gupta et al., 2008

3. MATERIALS AND METHOD

The detail of experiment methods and materials used during the course of research has been described under the following headings;

3.1. Location The experiment was conducted in the research plot of the agronomy farm IAAS, RAMPUR CHITWAN. This site is situated at 10 km west from Bharatpur, headquater of Chitwan district. The altitude of this site is about 256m from masl and located at 270 37’ North latitude and 840 25’ East longitudes. 3.2. Field layout: The experiment was laid in randomized complete block design and the experiment consists of 10 treatments each of four replications. The size of each plot was 4.4 m length and 3 m width. There was a bund of 0.5 m width between two plots and each replication was separated by 1 m bund. The spacing between two rows during the direct sowing of seeds was 20cm. Detail of field layout

Irrigation channel

Irrigation channel 1 m

T1O T7 T4 T2 T8 1m

T3 T5 T6 T1 T9

T3 T5 T9 T6 T1

T8 T2

T1O T4

Irrigation channel

Fig. Layout of plot for experiment

T1O T9 T8 T7 T6 T5 T4 T3 T2 T1

T1 T5 T2 T3 T4

T9 T1O

T6 T8 T7

Treatment details: a. Sukhha-1 (T1) b. Sukhha-2(T2) c. Sawamansuli sub-1(T3) d. Mansuli (T4) e. Sukhha-3 (T5) f. Radha-4 (T6) g. O.R(ramdhan) (T7) h. Makwanpur-1 (T8) i. Swarnasub (T9) j. Sabitri (T10)

3.3.CULTURAL PRACTISES

3.3.1 Field Preparation and clearing of Weeds Before carrying out the research in this field, the field was fallow and was fully covered with weeds, irrigation channel were also blocked. So, each plot (3.4*4 m2) was made weed free and weeds were incorporated into the soil. This activity was carried on 18thJestha, 2068. 3.3.2 Final land Preparation for Sowing and Fertilizer Application (Basal Dose) After 8th days of the initial field preparation, again each plot was dug for 2-3 times. At this time, the basal dose of fertilizer (60:60:40 kg NPK/ha.) was applied and covered with the soil. 3.3.3 Seed Selection for Sowing Before sowing seeds, the seeds were soaked in water for 24 hours and the bold seeds which settled down were used and the floating (diseased, fluffy and broken) seeds were discarded. After soaking for 24 hours, the seeds were dried for hours to remove excessive moisture and for ease of sowing. 3.3.4 Sowing of Seeds Seeds were sown under DSR technique. The row to row distance was maintained as 20 cm and the seeds were sown in the rows in continuous pattern on 27thJestha, 2068. The seed rate used was 50 kg/ha. 3.3.5 Field Inspection and Gap Filling From the second day of sowing, the field was inspected regularly. During inspection any grains uncovered by the soil were covered. The number of seedling emerging was counted taking a meter row length from the first sign of emergence to constant seedling number. To maintain the required population number, gap filling was carried out. Gap filling in each plot was done on 14DAS i.e. 10thAsad, 2068. Seed selection and preparation for sowing was done as earlier.

3.3.6 Hoeing For proper growth and development of any crop, oxygen is must. To ensure the oxygen supply in the roots of Direct Seeded Rice seedling, hoeing was done on 24DAS i.e on 20thAsad, 2068. 3.3.7 Weeding The weeds are the serious problem in rice field cultivated under DSR technique. The major challenge for farmers adopting DSR is effective weed management (Moody, 1991; Singh et al., 2003), as failure to eliminate weeds may result in low or no yield (Estorninos and Moody, 1998). So, the weeding was done several times. Manual weeding was done at 15 DAS, 45 DAS and 60 DAS. No chemical treatments were done for weed management. 3.3.8 Fertilizer Application The recommended dose of fertilizer was 120:60:40kg NPK/ha. The fertilizer used were urea, DAP, and MOP. Half dose of Nitrogen and full dose of Phosphorus and Potash were used in each plot as basal dose and remaining dose of Nitrogen was applied in 2 split doses. The first split dose (1/4 N) was applied on 31 DAS (27thAsad, 2068) and other remaining dose (1/4N) was applied at the time of panicle initiation (19thBhadra, 2068). 3.3.9 Harvesting The crop was harvested on Kartik, 29, 2068. It was left on the same plot so as to reduce the moisture content. After 4 days, the biological yield was noticed and was threshed. The grains were then dried to keep the moisture level of grains at about 12% and weight was taken. Table- 1 Detail of cultural operations in the experimental plots of rice during experimental period.

S.No. Particular Operation Date

1. Field Preparation 2068/02/18

2. Plot Preparation and Fertilizer application(basal dose) 2068/02/26

3. Direct Sowing of Seeds 2068/02/27

4. Reseeding 2068/03/10

5. Hoeing 2068/03/20 6. Weeding

1st weeding 2068/03/11

2nd weeding 2068/04/08

3rd weeding 2068/04/23

7. Fertilizer Application

Basal Application 2068/02/26

1st split Application 2068/03/27

2nd Split Application 2068/05/19 8. Harvesting 2068/07/29

9. Threshing 2068/08/04

4. OBSERVATION Biometric Observation A. Plant height was measured from the same 20 selected plants starting from 42 DAS (Shrawan

6, 2068). This operation was repeated 2 times at 10 days interval. The average of each treatment was taken.

Observation Table: 1 Treatment Plant height (cm)

42 DAS 52 DAS 62 DAS T1 46.03 58.43 67.17 T2 46.77 56.22 68.27 T3 33.91 42.63 51.26 T4 51.64 64.65 78.07 T5 49.13 60.2 67.41 T6 38.78 49.05 60.06 T7 41.76 53.81 58.96 T8 42.76 48.39 59.78 T9 34.20 44.45 55.97 T10 37.36 52.44 62.29

Observation Table: 2

Treatment Biological Yield(t/ha) Grain Yield(t/ha) Harvest Index(%)

T1 10.18 1.62 15.9

T2 8.5 1.29 15.2

T3 12 2.02 16.9

T4 12.6 1.55 13

T5 10.43 1.22 11.7

T6 10.81 1.42 13.1

T7 11.75 2.29 19

T8 14.81 2.82 19

T9 12.5 3.23 25.84

T10 9.92 2.26 23

5. RESULT AND DISCUSSION

Table A: Effects of plant height of rice varities under direct seeding condition at Rampur IAAS, Chitwan, 2011

S.N. Treatment Plant height (cm)

42 DAS 52 DAS 62 DAS

1. Sukhha 1 (T1) 46.325bc 59.38ab 68.02b

2. Sukhha 2 (T2) 46.773bc 56.22bc 68.27b

3. Sawa mansuli sub-1 (T3) 33.910f 42.63f 51.26d

4. Mansuli(T4) 51.642a 64.65a 78.07a

5. Sukhha3(T5) 49.130ab 60.03ab 67.41b

6. Radha 4 (T6) 38.778de 49.06de 60.07c

7. O.R. (T7) 41.755de 53.82bcd 58.96c

8. Makwanpur-1 (T8) 42.762cd 48.39def 59.85c

9. Swarnasub (T9) 34.202f 44.45ef 55.97cd

10. Sabitr1(T10) 37.355ef 52.44cd 62.29bc

Mean 42.263 53.108 63.018

LSD (=0.05) 4.271 5.731 6.195

SEm (±) 1.472 1.975 2.135

CV (%) 6.97 7.44% 6.78%

Means separated by DMRT and columns represented with same letters are not significant at 5% level of significance.

A N A L Y S I S O F V A R I A N C E T A B L E ( HEIGHT AFTER 42 DAS)

K Degrees of Sum of Mean F

Value Source Freedom Squares Square Value Prob

-----------------------------------------------------------------------------

1 Replication 3 143.047 47.682 5.5021 0.0044

2 Factor A 9 1373.821 152.647 17.6140 0.0000

-3 Error 27 233.988 8.666

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Total 39 1750.856

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Coefficient of Variation: 6.97%

s_ for means group 1: 0.9309 Number of Observations: 10

y


y




-----------------------------------------------------------------------------

1 Replication 3 220.115 73.372 4.7020 0.0091

2 Factor A 9 1818.057 202.006 12.9456 0.0000

-3 Error 27 421.316 15.604

-----------------------------------------------------------------------------

Total 39 2459.48



y


y




-----------------------------------------------------------------------------

1 Replication 3 37.971 12.657 0.6943

2 Factor A 9 2088.667 232.074 12.7300 0.0000

-3 Error 27 492.223 18.230

-----------------------------------------------------------------------------

Total 39 2618.862

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y


y

TABLE B: Effect of different varieties on grain yield, biological yield and harvest index (HI) of DSR at IAAS, Rampur, Chitwan, 2011A.D

S.N. Treatment Biological Yield (t/ha)

Grain yield (t/ha) HI (%)

1. Sukhha 1 (T1) 10.19bc 1.625cdef 15.75cd

2. Sukhha 2 (T2) 8.500c 1.295f 15.20cd

3.

Sawa mansuli sub-1 (T3)

12.00b 2.025cde 16.90bcd

4. Mansuli(T4) 12.06b 1.555def 16.00cd

5. Sukhha3(T5) 10.44bc 1.222f 11.75d

6. Radha 4 (T6) 10.81bc 1.415ef 13.50d

7. O.R. (T7) 11.75b 2.230bcd 22.00abc

8. Makwanpur-1 (T8) 14.81a 2.822ab 18.75bcd

9. Swarnasub (T9) 12.50ab 3.230a 25.88a

10. Sabitri(T10) 9.938bc 2.263bc 23.35ab

Mean 11.300 1.968 17.907

LSD (=0.05) 2.32 0.6374 6.152

SEm (±) 0.8020 0.2197 2.120

CV (%) 14.20% 22.35% 23.68%

Means separated by DMRT and columns represented with same letters are not significant at 5% level of significance.

A N A L Y S I S O F V A R I A N C E T A B L E (BIOLOGICAL YIELD)



-----------------------------------------------------------------------------

1 Replication 3 7.550 2.517 0.9780

2 Factor A 9 107.869 11.985 4.6575 0.0009

-3 Error 27 69.481 2.573

-----------------------------------------------------------------------------

Total 39 184.900

-----------------------------------------------------------------------------



y


y

A N A L Y S I S O F V A R I A N C E T A B L E ( GRAIN YIELD)



-----------------------------------------------------------------------------

1 Replication 3 0.991 0.330 1.7080 0.1890

2 Factor A 9 16.337 1.815 9.3833 0.0000

-3 Error 27 5.223 0.193

-----------------------------------------------------------------------------

Total 39 22.551



y


y

A N A L Y S I S O F V A R I A N C E T A B L E ( HI)



-----------------------------------------------------------------------------

1 Replication 3 99.219 33.073 1.8392 0.1639

2 Factor A 9 738.160 82.018 4.5612 0.0010

-3 Error 27 485.509 17.982

-----------------------------------------------------------------------------

Total 39 1322.888

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y


y

DISCUSSION: Effect of treatment on growth attributes (plant height) of rice

Plant height is one of the important growth parameters of any crop plant as it determines or modifies the yield attributing characters and finally shapes the grain yield. For the ideal rice variety, the height of the plant should be medium type. The plant height (cm) in DSR as influenced by different treatment is presented in table A.

Analysis of varience shows significanct difference (p<0.05) in plant height among different treatments at 42, 52, and 62 DAS (table A). the mean plant height at 42 DAS, 52DAS, 62 DAS was 42.263cm, 53.108cmand 63.018 respectively.

At 42 DAS, the lower plant height 33.91 cm was observed in Sawa mansuli sub- 1, however it was par with sabitri and swarnasub-1. Whereas significantly higher plant height was recorded in mansuli i.e. 51.64cm.and was par with sukkha -3 (49.13). sukkha-3 was par with sukkha-1,2.

At 52 DAS significantly higher plant height was observed in mansuli i.e 64.65cm. Which was par with sukkha-3 and sukkha- 1 and lower plant height was observed in sawa mansuli sub-1 i.e. 42.63 cm.which was par with sawa mansuli and makanpur-1.

At 62 DAS significantly higher plant height was observed in mansuli i.e 78.07 cm and lower plant height was observed in sawa mansuli sub-1 i.e. 51.26 cm.which was par with swarnasub.

Effects of treatments on grain yield, straw yield and harvest index in IAAS, Rampur,Chitwn, 2011.

a. Grain yield: grain yield is the treatment effect in the experiment. Grain yields varied significantly due to treatments. Grain yield of crop is the result of combine effect of growth, development and yield attributes. This parameters are mainly governed by heredity of the particular genotype.

Economic yield (t/ ha)

Fig. relationship between economic yield and HI in DSR under different treatments at IAAS, Rampur, Chitwan,2011

The average grain yield in the experiment was 1.968 t/ha and is varied form 3.23t/ha to 1.222 t/ha (tab. B). The highest significant grain yield was found from the swarnasub (3.23t/ha) which was par with makawan pur -1 (2.822) and lowest grain yield was found in sukkha 3 which was par with sukkha 1,2, masuli and radha -4.

b. Biological yield: it is an important factor to determine grain yield and straw yield. Rice verities are selected not only on the basis of grain yield but emphasis is also given for straw yield. The average biological yield in the experiment was found to be 11.30 t/ha. The highest biological yield was noticed in makanpur -1 ( 14.81 t/ha) which was par with swarnasub and lowest yield was noticed in sukkha -2 (8.50) which was par with sukkha – 1,3, radha -4 and sabitri.

c. Harvest index: it is the ratio of economi yield to the biological yield. It determines the productive potentiality of any crop variety. To obtain higher grain yield, balance crop growth at different stages most be achieved. Balanced growth is reflected in the higher ratio of economic yield to that of the total dry matter produced (Reddy and Reddy, 2002) The average harvest index was fond to be 17.907 %. The highest HI was found from swarnasub ( 25.88%) which was par with sabitri and O.R. and lowest was found form sukkha- 3 ( 11.75) which was par with sukkha – 1,3 and swarna sub-1, mansuli, radha- 4 and makanpur- 1.

y = 5.683x + 6.7219 R² = 0.5506

0

5

10

15

20

25

30

35

40

0 1 2 3 4 5

Series1

Linear (Series1)

6. SUMMARY AND CONCLUSION

Selection of the best verity performing well in the DSR technique at farmers field in Chitwan is the major problem faced by the farmers. Thus this research was designed with the objectives of evaluating the performance of different rice varieties.

An experiment was carried out on direct seeded rice in the farm of Agronomy, IAAS, Rampur,Chitwan, during rice season of ,2011 in Randomized Complete Block Design (RCBD) with ten treatments and four replication.

The result showed that mansuli had, highest significant plant height on 42 DAS and this trend was found to be same on 52 and 62DAS.

The highest significant grain yield and HI was recorded on swarnasub, where as makanpur-1 showed the highestsignificant biological yield.

6. LITERATURE CITED

Adhikari, N.P. 2004. Rice research and production in Nepal: Current status and future direction. Rice research in Nepal proceeding of the 24th summer crop workshop june 30- 31st, 2004. Nepal Agriculture Research Council. National Agriculture Research Programme, Hardinath, Baniniya, Dhanusa, 2004, pp 1-5

Balasubramanian, R.,J. Krishnarajan and S. Ramesh. 2004. Economical use of water for direct – seeded rice. In : Peng, S. and B. Hardy(eds.). Rice research for fiid security and poverty alleviation. Proceedings of the International Rice Research Conference, Los Banos, Philippines, 31 March , 3 April,2000.

Bhandati, R.C.2004. physio- chemical Quality of rice. Proceeding of National workshop on Rice Post harvest technology, 2004. Nepal Agriculture Research Council.

Boumann, B. A. M. and T.P. Toung. 2001. Field water ,management to save water and increase productivity in irrigated lowland rice. Agric. Water manage. 49: 11-30.

FAO.2010. proven technologies for smallholders. Weed management for direct seeded rice. Technology for agriculture.

FAOSTAT, 2005. Agriculture Statistical Database, available at http://apps.fao.org/Rome

Gupta, R.K., J.K.Ladha, S.singh, R.J.Singh M.L.,Jat, Y.Saharawat, V.P.Singh, S.S.Singh,G.sah,M.S.Gill,M.Alam,H.Mujeeb,U.P. Singh, R. Mann,H. Pathak, B.S. Singh,P Bhattacharya ad R.K. Malik, 2006. Production Technology for diredt seeded Rice. Rice wheat consortium Technical Bulletin 8. New Delhi, India. Rice wheat consortium for the Indo-Gangetic Plains. Pp 16.

IRRI. 2007. Direct seeding of rice get warm approval in the Indo- Gangatic plain. International Rice Research Institute, Manila. Philippines.

Johnson, D.E. and A.M. mortimor. 2005. Issues for weed management in direct- seeded rice and the development of decision-support frameworks. In: workshop on direct seeded Rice in the Rice –Wheat system of the Indo- Gangatic plains. 1-2 February , 2005. G. B. pant University of Agriculture and Technology, Pantnagar, Utaranchal, India. Pp.8.

Khan, S.R.A. 2007. Switching over to direct seeded rice seeding technology. http://DAWN.com

Kim, K.U. and D.H. Shin. 2007. Rice allelopathy research in Korea. In: Olofsdotter, M(eds). Allelopathy in Rice. International Rice Research Institute, Manila, Philipines, 2007.

Mann, R.A., S. Ahmad, G. Hasan and M.S. Baloch, 2007. Occurrence of weed species in transplanted aman rice crop. Pak.J.weed Sci. Res. 13 (3-4):219-226.

http://apps.fao.org/Rome

http://dawn.com/

NARC. 2004. Rice research in Nepal, Proceedings of the 24th summer crop workshop, 30-31 June, 2004. Nepal Agriculture Research Council. National Rice Research Program, Harinath, Baniniya, Dhanusha, 2004.

NARC. 2008. Annual Technical Report, 2007/2008. . Nepal Agriculture Research Council, Regional Agricultural Research Station, Parwanipur, Bara. Pp.9.

Pandey , S. and L.E. Velasco. 1998. Economics of direct- seeded rice in Iloilo:lessons from nearly two decades of adoption. Social Science Division Discussion Paper. International Rice Research Institute, Manila, Philipines.

Reddy, K.R., H.F.Hodegs and J.M.Mckinion. 1997. Crop modeling and applications , a cotton example. In : L. S. Donald(ed.). Adv. In Agron. 59; 334.

Sah, G. and R.P. Sah. 2004. Alternative technique of rice transplanting. In A.K. Gautam, T. Akhatar, B. Chaudhary, J. Gaire, K.R.Bhatta(eds.). rice research in Nepal proceedings of the 24th summer workshop June 28- 30, 2004. NARC, National Rice Research Program, Hardinath, Baniniya, Dhanusha, 2004. Pp. 412-417.

Singh, B., Y.S. Saharawat, M. Gathala, J. Ladha and R.K. Malik. 2008. Integrated management in DSR under different cro establishment methods in rice- wheat system of Indo-Gangetic Plain. George R. Brown Convention center, exhibit hall E. 6 oct. 2008.

Tripathi, J.,P.R. Hobbs and G. S. Giri. 2000. Effect of tillage and crop establishment practices on the productivity of rice- wheat systems. Proceedings of wheat research papers presented at National Winter Crops Research Workshops Sep. 12-14, 2000. NARC, NWRP, Bhairahawa, 2000. Pp.135-144.

Yadav, D.S., G.Singh, Y. Singh, V.P. Singh, R.K. Sinha, D. Johnson, A.M.Mortimer, C.Riches and A.Orr. 2005. Promotion of integrated wheat management for Direct- seeded Rice on the Gangetic Plains of India.

Yadav, S. 2006. Direct- Seeded Rice (DSR): promising resource conservation technology. Centre for Advancement of Sustainable Agriculture. Telesupport Network, 2006.