Abstract:
A research project was initiated at the Agricultural Research Institute, Dera Ismail
Khan, NWFP, Pakistan during 2002 and 2003; to provide appropriate rice cultivation
technologies that are agronomically practicable and economically viable under the
agro-climatic conditions of the area. The research project was based on field-oriented
problems faced by the paddy growers, which was also evident from face to face
interviews by 50 rice growers, actively involved in rice production from major rice
growing villages of the area. field experiments relating to time of transplanting
and number of seedlings hi!r' and techniques for weed control in transplanted and
direct wet-seeded rice were laid out in Randomized Complete Block Design (RCBD)
with split-plots arrangements, replicated 4 times. The transplanting dates of nursery
and methods of planting were maintained in main plots while the number of seedlings
hill" and weed control techniques were kept as sub-plots. The sub-plot size was 2 x
5 m" The trial pertaining to impact of seeding techniques in transplanted and direct wet-seeded rice was deSigned in RCB with a plot 3 x 5 m2, replicated 4 times.
Well-adapted coarse rice variety IR-6 was used in the research project. Thirty days
old rice nursery was used in transplanted plots while wet pre-germinated seed was
broadcast in direct seeded plots. Data were recorded on various growth and yield
parameters like plant height (em), productive tillers m-', unproductive tillers m-',
panicles m-', spikelets panicle-" sterility and normal kernels percentage, 1000-grain
weight (g), paddy yield (t ha') and straw yield (t ha') The data were also recorded
on leaves planr', leaf area index (LAI), net assimilation rate (NAR) at 45 and 90 days
after sowing (DAS), stem borer moths' resting behaviour at 30, 45 and 60 DAS and
white heads planr' after 90 DAS in all experiments of the project.
The sample size in experiment 1 was determined by using simple random sampling
procedure of probability sampling. A sampling frame was developed that carried
details of farmers involved in rice production. This was identified by collecting
information from the key informants. The findings of the survey elucidated that water
shortage, high cost of inputs, non-availability of skilled labour during peak planting
season, sub-optimal plant population, weeds and pest infestation, high dependence
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of knowledge on nearby growers and low price of nce in Ihe locel markel were the
major restrictions in higher yields of rice, In experiment 2, the effects of transplanting
dates and number of seedlings hilr' were found 10 be significant in most of the
agronomic and physiological parameters studied The highest paddy yield during 2002
and 2003 (5 and 8,1 t ha") respectively, higher net return of Rs, 7,830 and 23,330
/la"and Benefil Cost Ralio (BCR) of 0.44 and 1,32 were recorded on 20'h June
planted crop with 1 seedling hiW' during both the expenmental years, Similarly in
experiment 3, the effect of planting tec/1niques (transplanting VS, direct seeding) and
weed control practices including granular herbicide Sunstar 15WG (Ethoxy sutfuron),
conventional hand weeding and herbicide Machete 60EC (Butachlor) Significantly
influenced the yield and yield centributing attributes during either year of the study
Both the Sunstar and Machete application proved their efficacy against the weeds
but could not match with hand weeding treatment Minimum weed population m', dry
weed biomass g m" after 30, 60 and 90 DAS and maximum paddy Yletd (5.7 and 8.5
t he") during both the experimental years and its assOCiated components were
receded in transplanting method as compared to direct seeding. Similarly, among
weed control strategies, the paddy yield, net return of Rs,13, 815 and 27,815 ha'and
BCR were the highest in hand weeding, followed by herbiCide application of Machete
60EC, The direct seedmg method could not perform in a good way in terms of low
paddy yield and high weed infestation. While in experiment 4, the effect of seeding
techniques was significant for most of the agronomic and physiological parameters
However, transplanting Hat and parachu1e planting techniques showed the outstanding
performance for most of the characters investigated. Maximum net relum of Rs. 12,630
and 15,730 and 6,050 and 14,800 was recorded In transplanting on flat and parachute
planting techniques, respectively dunng both the planting seasons Other seeding
techniques such as diract seeding on flat, direct seeding on ridges and transplanting on
ndges could not excel transplanting on flat and parachute planting in most of the
ahributes recorded.
On the basis of research findings, it is concluded that conventional transplanting
technique on flat with a plant-ta-plant and row-ta-row spaCing of 20 em is most suitable
on planting date 20" June with 1 seedling hill". Among weed control practices, hand
weeding is most effective, followed by herbicide treatment Machete 60EC Nursery
preparation and seedling broadcasting of parachute technology although, a
cumbersome job but produced higher paddy yield and nel return per unit area.