Correlation and path coefficient were computed to assess the association between direct and indirect influences of different characters on yield in hybrid rice. The grain yield exhibited positive association with total number of spikelets m-2, number of filled spikelets m-2, spikelet sterility, thousand grain (test) weight, grain straw ratio except for number of panicles m-2. The number of filled spikelets m-2 was most significantly and positively correlated with grain yield ha-1. The path analysis revealed their highest positive direct effect on biological yield followed by harvest index and crop duration. The contribution of number of filled spikelets m-2, spikelets sterility, thousand grain (test) weight, number of panicle m-2, grain: straw ratio and dry matter production was positive but associated more indirectly to biological yield. Negative direct effect of growing degree days, total number of spikelets m-2, heliothermal units, ripening periods, plant height and days taken to 50% flowering was established.

Key words: Hybrid rice, grain yield, GDD, heliothermal units and tarai condition

Comparative efficacy of diallel (Method 2 and 4 Model 1), partial diallel (sample size more and less than n/2) and line x tester analyses were studied to understand the nature of gene action of 14 traits (both quantitative and qualitative) affecting grain yield in rice. Both the methods of diallel analysis and partial diallel analysis with “s” equal to 6 (i.e. more than n/2) gave similar and comparable results. The nature of tester parents played a significant role in the estimates of gene effects. Line x tester analysis using tester parents with broad genetic base gave results fairly close to the diallel and partial diallel analysis. Hence, it was concluded that the line x tester analysis with profusely selected testers or partial diallel analysis with sample size equal to more than n/2 may be preferred to screen a large number of genotypes.

Key words: Diallel, partial diallel, line x tester mating designs, gene action, rice, comparison of mating designs

The genetics of salt tolerance in rice was investigated both at seed germination and in seed/seedling derived calli using six parents diallel analysis., excluding reciprocals. Test materials involved tolerant (CSR-5 and CSR-10), moderately tolerant (NDR-501 and SAR-41) and susceptible (IET12860 and IET 11149) genotypes. Rate of germination index (RGI), germination stress index (GSI) at seedling phase, fresh and dry weight (FW and DW) of calli, corresponding survival ratio of callus were studied for their combining ability and gene action. Analyses revealed both additive and non-additive gene effects for most of the traits: the former being more pronounced than later, especially under stress medium: for fresh and dry callus weight and callus survival under controled condition, both additive and non-additive gene effects were equally important. The genotypes like CAR-10, CSR=5 (tolerant) and NDR-501 (moderately tolerant) were found to be the best combiners under both Control (CM) and salt medium (SM). The crosses like CSR-10 x CSR-5, CSR-5 x NDR-501, NDR-501 x IET 12860 and NDR-501 x IET 11149 exhibited maximum SCA effects for fresh and dry weight of calli in control medium and salt medium and its terminal survival under CM.

Key words: Salinity, seed derived callus, rice, combining ability, gene effects

An experiment was conducted to find out grain yield, nitrogen concentration in the third leaf and nitrogen uptake by hybrid rice under different planting dates and nitrogen levels during 1999 and 2000. The hybrid rice planted on July 5 or 20 produced significantly higher nitrogen concentration in the third leaf, grain yield and nitrogen uptake by both grain and straw. The delayed planting between August 5 or 20 significantly reduced these crop parameters. The reduction in grain yield was to the extent of 14.06 and 28.23 %, respectively compared with planting of July 5. Number of effective tillers, grains panicle-1, test weight, grain yield, N concentration in third leaf at different stages, nitrogen concentration and uptake by grain and straw increased significantly with increasing levels of nitrogen from 50 to 150 kg N ha-1. Highest R2 value has been observed for regression equation between N concentration in third leaf at 60 DAT and grain yield.

Key words: Planting date, N level, N concentration in third leaves, Grain yield and N uptake, hybrid rice

A field experiment was conducted on sandy loam soil during wet season of 2003 and 2004 to evaluate the grain yield and economic feasibility of direct wet seeded aromatic rice under different fertility levels viz. 80: 40: 40; 100: 50: 50; 120:60:60 kg ha-1 of N, P2O5 and K2O respectively and weed management practices viz. anilofos @ 0.4 kg a.i ha-1, butachlor @ 1.5 kg a.i ha-1, 2 handweedings and weedy check. There was increase in yield and net income by subsequent increase in fertility levels. Among weed management practices, 2 handweeding recorded highest grain yield followed by anilofos. The maximum grain yield was observed in plots treated with 120: 60: 60 kg ha-1 of N: P2O5: K2O respectively and 2 handweedings, however, higher net return and benefit cost ratio(BCR) was observed in 120: 60: 60 kg ha-1 of N: P2O5: K2O and anilofos. treatment. Maximum weed index was observed in weedy check plots (67-69 %). The unit increase in intensity of monocots, dicots and weed dry weight causes decrease in rice grain yield by 2.18, 1.64 and 2.85 q ha-1 respectively.

Key words: Direct seeded rice, fertility levels, weed management

Productivity, nutrient uptake and economics of wet season rice under IPNS (Integrated plant nutrient supply system) in rice-based fodder cropping systems were studied during 2002 and 2003 in red lateritic soil. Pooled data over two years revealed that various yield attributes, yield and NPK uptake of rice significantly increased when rice was succeeded by berseem in rice-berseem sequence. Application of 50% recommended dose (RD) of NPK (RD= 60-30-30 kg ha-1 of N-P2O5-K2O) + dhaincha @ 10 t ha-1 produced significantly higher yield attributes, yield and NPK uptake of rice among different nutrient management practices. This treatment produced the highest grain yield (4.495t ha-1) over 100% RD of NPK (4.201 t ha-1) and 50% RD of NPK +FYM @ 10 t ha-1 (4.122 t ha-1). Rice-berseem, sequence, along with 50% RD of NPK +dhaincha @ 10 t ha-1 in rice only provided the highest gross return (Rs. 29,915 ha-1), net return (Rs. 17,860 ha-1) and return rupee-1 invested (2.48) in comparison to rice in rice-oats, rice-fenugreek and rice-lathyrus systems.

Key words: Wet season rice, IPNS, fodder crops, cropping systems

The effect of irrigation levels and weed management practices on yield, yield components, water-use efficiency and economics of hybrid rice (cv. Pro Agro 6444) was studied. The results revealed that continuous submergence of 5 ± 2 cm with weed free check (at fortnight interval) showed maximum grain yield (8.22 t ha-1) and yield attributes. Continuous submergence with unweeded control consumed maximum water (153 cm) and lowest water-use efficiency (4.02 kg ha-1 mm-1), while irrigation (5 cm) at 3 days after disappearance of ponded water with weed free check gave the maximum water-use efficiency (16.31 kg ha-1mm-1). The maximum net return (Rs.33,565 ha-1) was obtained under continuous submergence with weed free check, however, the benefit: cost ratio (1.94) was highest under continuous submergence with pre-emergence application of Pyrazosulfuron ethyl 10% WP @ 25 g ha-1 at 7 days after transplanting.

Key words: Hybrid rice, irrigation, weed management, yield potential, water-use efficiency, economics

System based nutrient management practice for rice– rapeseed cropping sequence was studied in a field experiment during 2003-04 and 2004-05. Application of FYM at 2.5 t ha-1 + Eupatorium at 2.5 t ha-1 recorded maximum grain yield of rice (3.63 t ha-1), productivity (4.68 t ha-1) and economics (Rs.12,621 ha-1) of the system. The highest residual effect of organics on rapeseed seed yield was noticed with FYM at 5 t ha-1. Application of 100% recommended dose of fertilizer (RDF: NPK 60:60:40) to rice followed by 50% RDF to rapeseed recorded highest rice grain yield as well as system productivity (4.64 t ha-1). However, no significant difference was observed in seed yield of rapeseed among the inorganic treatments. The maximum gross return, net return and benefit cost ratio was registered with 100% RDF to rice + 50% RDF to rapeseed.

Key words: Rice, rapeseed, Eupatorium, Alnus, system productivity, net return, benefit: cost ratio

The effect of variety and integrated nutrient management in rice-rapeseed cropping sequence was studied. Both the varieties, Vandana and IR 6008-32 were at par with respect to grain and straw yields. The nutrient management practices had a significant effect on developmental phases of upland rice. The crop flowered and matured early due to application of recommended dose of fertilizer (RBD) + Single super phosphate incubated with FYM (1:2) + 5 t FYM ha-1 with highest grain (2.60 t ha-1) and straw (6.90 t ha-1) yields. The soil fertility status with respect to pH, organic carbon and total nitrogen were affected significantly by different nutrient management practices in rice. It had a significant effect on the performance of succeeding rapeseed crop (Var. TS-38). Highest seed (0.64 t ha-1) and stover yield (1.32 t ha-1) was recorded with application of 50% RDF + 5 t FYM ha-1, which was at par with application of RDF + SSP incubated with FYM+ 5 t FYM ha-1. Number of primary branches plant-1 and number of siliqua plant-1 were significantly affected by above treatments.

Key words: Upland rice, rapeseed, nutrient management, soil fertility

Stem borer complex of rice at the Instructional-Cum-Research Farm, Assam Agricultural University (AAU), Jorhat, Assam, during 2005, comprised of five species of lepidopteran borers viz., the pyralids, Scirpophaga innotata (Walker), S. incertulas (Walker), Chilo suppressalis (Walker), C. polychrysus (Meyrick) and the noctuid Sesamia inferens (Walker). S. innotata was the predominant species followed by S. incertulas while S. inference was the least abundant species of the borer complex. Larval population of S. innotata was 43.39, 41.96 and 35.43 per cent of the total borer population at tillering, maximum tillering and at heading stages of the crop, respectively during the Ahu season, while in Sali season the corresponding percentage was 44.73, 41.48 and 37.50. The population of S. innotata as hibernating larvae was 34.4 per cent. Moth population of S. innotata constituted 73.71 and 72.84 per cent of the total borer complex during Ahu and Sali seasons, respectively. Pink borer, S. inferens was the least abundant species during both the Ahu and Sali seasons.

Key words: Scirpophaga innotata, S. incertulas, Chilo suppressalis, C. polychrysus, Sesamia inferens, rice, relative abundance, Assam

Aqueous extracts from twenty plants were tested for their antifungal activity against Fusarium moniliforme inciting foot rot of paddy. Test results showed a differential activity of the plant extracts against the mycelium growth. The strong inhibitory effect was shown by root extracts of Asparagus racemosus. The bark extracts of Acacia arabicae and leaf extracts of Camellia sinensis showed appreciable inhibitory effect against the test fungi. Other plants viz., Callistemon lanceolatus > Aegle marmelos >Calotropis procera >Brassicae campestris >Aloe vera showed inhibition in that order.

Key words: Fusarium moniliforme, Antifungal, plant-extracts

Grain yield ability and grain quality traits of 22 varieties were studied at Central Rainfed Upland Rice Research Station, Hazaribag. It was observed that the varieties Vandana, Kalyani 2 and Anjali proved their stability and superiority to the check variety Heera resulting in 97.5, 97.0 and 95.0 % higher yields respectively. The grain yield was 5.8 % more in the bunded upland than in the unbunded upland plots. With regard to physico-chemical characteristics, the mean head rice recovery (56.8 %) and the kernel test weight (40.8%) were recorded under unbunded upland. Kernel length after cooking, volume expansion ratio and elongation ratio (10 mm, 3.7, 1.5) were estimated. Among twenty two upland rice varieties, six varieties namely Kalinga III, Kalyani 2, Heera, VL 221, RR 366-8 and RR 363-36 were comparable and satisfied the minimum acceptable standard of grain quality traits.

Key words: Short duration, bunded upland, drought tolerant, crop lodging, yield index

Workload of 30 women belonging to the age group of 21 to 40 years was compared during weeding with the use of Cono weeder in paddy crop grown in SRI method against conventional method of hand weeding. It was found that cono weeder enhanced the pace of work and doubled the productivity, saved time up to 76 per cent and optimized the human effort through improved postures and reduced the muscular fatigue as compared with the hand weeding process.

Key words: Workload – women using cono weeder, SRI cultivation

Farmers’ perception of suitability criteria for direct seeded upland ‘Ahu’ rice varieties with emphasis on the role played by ethno-cultural settings through application of various Participatory Rural Appraisal (PRA) tools and experimentation in the farmers’ field was studied. It indicated that any upland ‘Ahu’ rice variety to be acceptable to the farmers of the study area should be high yielding, non-lodging, semi-tall (@120 cm), early maturing (@100 days) with quick early vigour, deep green leaves, well exerted long and heavy panicles, reasonable duration of seed dormancy, desired grain quality and resistance to rice gundhi bug, stem borers, blast and brown spot disease. The study indicated that the farmers’ suitability perception of a variety even for similar growing environment might vary in different accounts due to ethno-cultural diversity suggesting the requirement of considering the ethno-cultural settings too along with the agro-ecological parameters of the target environments while deciding the breeding goals.

Key words: Upland, ‘Ahu’ rice, ethno-cultural variation, farmers’ perception, PRA tools

One hundred farm women of Pipili block of Khurda district of Orissa were selected to impart training on mushroom cultivation. Then impact assessment was done to know the socio-economic development after mushroom cultivation, constraints face by them and future suggestions. The study revealed that 70% of women mushroom growers had improved their occupation followed by improvement in ‘standard of living’ (36%), ‘better saving’ (30%), ‘knowledge and attitude’ (24%) and ‘social status’ (10%). As perceived by the farm women, they face the maximum constraint in ‘value added items’ and least problem in ‘lack of awareness in mushroom cultivation’. Sixty percent of the respondents stated that lack of ‘quality supply of spawn bottle’, ‘practical manual for cultivation’ and ‘insurance’ were the three major constraints for successful mushroom entrepreneurship.

Key words: Mushroom enterprise, SHG and farm women

Thirty two upland rice genotypes were assessed for study of genetic variability and construction of selection indices for enhancing selection efficiency. Observations on ten metric characters like days to 50% flowering, plant height, flag leaf area, panicle number, panicle length grain number, grain fertility %, 100 grain weight, harvest index and grain yield were recorded. The analysis of variance revealed the presence of considerable amount of variation among the test genotypes for all the characters. This was also supported by mean, range, GCV and PCV. Using grain yield as economic criterion, five selection indices were constructed. The relative efficiency of selection on the basis of selection indices is expected to increase upto 114.371%. On the basis of selection criteria, the promising genotypes selected were OR 1752-3, OR 1603-7, OR 2088-4, OR 2087-2, OR 1659-3, OR 2049-1, OR 2048-1, OR 2069-1, OR 2077-5 and OR 1920-7.

Key words: Rice, selection index, genetic variability

Heterosis, heterobeltiosis and standard heterosis were estimated for grain yield, its attributes and other physical characters in 32 cross combinations generated through Line x Tester mating design. In general, the estimates of heterosis values were low for physical characters when compared to yield and yield components. Nine hybrids manifested positive and significant heterosis over midparent, better parent and standard check for grain yield plant-1, of which AD 95157 x IR 50, MDU 5 x IR 50, AD 95157 x ADT 43, MDU 5 x ADT 36, AD 95157 x ADT 36 and AD 95137 x ADT 36 were top rankers. On considering both yield and physical traits together the crosses MDU 5 x IR 50, MDU 5 x ADT 36, AD 95157 x ADT 36, AD 95157 x ADT 43, AD 95157 x IR 50 and AD 95137 x ADT 36 could be isolated for possessing desirable average heterosis, midparantal heterosis and standard heterosis for yield and grain traits.

Key words: Heterosis, yield components, grain characters, rice

The effect of different nutrient management practices on the performance of both rice and blackgram crop grown in rice-blackgram utera cropping sequence was studied in an on-farm trial carried out in five different villages of Tangi block in the Khurda district of Orissa during three consecutive crop growing season of 2001-02, 2002-03 and 2003-04. The highest grain yield (38.4 q ha-1) of rice as well as the highest seed yield (5.87 q ha-1) of blackgram was recorded in the treatment where additional 20 kg ‘P2O5’ of blackgram was applied to rice as basal along with the recommended dose of fertilizer. The highest net return (Rs. 15,618) and benefit : cost ratio (2.28) were also recorded from the same treatment plots.

Key words: Nutrient management, rice, blackgram, utera cropping

The species composition of stem borers prevalent in Assam during wet season 2004 and 2005 was studied. The results revealed that all the species of stemborers are prevalent in this region. Amongst the species, yellow stem borer (34 - 40 % in 2004 & 22.54-77.41 % in 2005) and white stem borer (39 - 43 % in 2004 and 18.27 - 67.64 % in 2005) showed consistently higher population over the other species at all the three stages of the crop growth.

Key words: Stem borer, species composition, rice, Assam

Three native Trichoderma spp viz., T. viride, T. harzianum and T. hamatum were screened for their efficacy in controlling the rice sheath blight pathogen, Rhizoctonia solani Kuhn. In- vitro dual culture studies revealed maximum inhibition of R. solani with T. harzianum (76.47%), followed by T. viride (65.03 %) and T. hamatum (63.43%). An inhibition zone was noticed in case of T. harzianum and a yellow halo prevailed in dual culture studies for a period of one week, indicating antibiosis. Screening for production of non-volatile metabolites against the radial growth of R. solani revealed the increase in inhibition of the test pathogen with an increase in concentration of the culture filtrate. Among the three Trichoderma spp., T. harzianum was proved effective in inhibiting the growth of R. solani (44.50% inhibition) at 100% concentration of the culture filtrate, followed by T. hamatum (38.63% inhibition) and T. viride (35.37% inhibition). In case of volatile metabolite production, maximum inhibition of the test pathogen was obtained when the cultures were exposed to 15 and 25 day - old species of Trichoderma spp. Among the Trichoderma spp, maximum inhibition of the radial growth of R. solani was obtained when 25-day-old culture of T. harzianum (49.17 % inhibition) was used, followed by T. viride (36.63%) and T. hamatum (36.37%).

Key words: Rice, sheath blight, biocontrol, Trichoderma, metabolites