Showing papers in "Annals of Agricultural Research in 2006"

Character association and path analysis in rice (oryza sativa l.)

Abstract: Thirty F1 hybrids and thirteen parents were studied for estimating the genotypic and phenotypic correlation coefficients and path effects of yield attributing traits on grain plant-1. Grain yield plant-1 had significant positive association with harvest index, grain yield panicle-1, filled grain yield panicle-1, productive tillers plant-1, harvest index and filled grains panicle-1 were the major yield contributing traits to be given selection pressure for improving yield in rice.

Genetic divergence in indian mustard

Abstract: Precise information about the extent of genetic divergence and on characters used for discrimination among population is crucial in any crop improvement programme. The existence of heterosis in a hybrid usually demonstrates the existence of some degree of genetic diversity. Therefore, the nature and magnitude of genetic divergence and the characters contributing to genetic diversity were studied among fortythree genotypes of Indian mustard using D 2 statistic. Days to 50% flowering (10.42%, 8.91%), days to maturity (23.80%, 22.64%), plant height (31.02%, 31.54%), primary branches (0.99%, 0.91%), secondary branches (2.31%, 1.92%), main shoot length (11.29%, 12.88%), siliquae on main shoot (6.83%, 7.77%), siliqua length (0.64%, 0.68%), seeds/siliqua (1.93%, 1.97), 1000-seed weight (0.84%, 0.79%), seed-yield/plant (4.42%, 3.47%) and oil content (6.27%, 6.48%) contributed to total divergence in varietal improvement programme.

Studies on influence of biofertilizers and bioregulators on flowering, yield and fruit quality of strawberry cv. sweet charlie

Abstract: Experiment was conducted to study the response of biofertilizers and bioregulators on strawberry crops. Results indicated that dual inoculation of Azotobactor and Azospirillum with 60 kg nitrogen/ha in conjunction with 100 ppm GA3 proved most effective in increasing fruit set, early flowering, yield and also have a significant improvement in fruit quality i.e. berry size, weight and volume. The maximum TTS, total sugar and ascorbic acid content were obtained with the same treatment combination, however, the effect on acidity and TSS/acid ratio was found to be non-significant.

Exploitation of combining ability for heterosis in maize (zea mays l.)

Abstract: Combining ability and hetorosis studies were carried out using 45 single crosses derived form 15 x 3 line x tester mating for grain yield, days to silking, plant height, cob height, Number of leaves per plant, days to brown husk, number of grains per row and 100-grain weight. Analysis revealed that both additive and non-additive gene effects were more important for all the characters. From the results, inbred lines L3, L5, L7, L10 and L15 were found good general combiners for grain yield. On the basis of heterosis and sca effects four hybrids L5 x T1, L6 x L10 x T1 x T3 were found superior for yield and yield contributing characters.

Effect of plant population and fertility levels on growth and npk uptake by sweet corn (zea mays l.) cultivars

Abstract: A field experiment was conducted during kharif 2001 and 2002 to study the effect of plant population and fertility levels on growth and NPK uptake by sweet corn (Zea mays L.) cultivars. Test cultivars did not significantly differ in respect of growth parameters, yield and nutrient uptake. Plant population at 55 thousand/ha gave significantly higher dry matter accumulation at harvest. However, successive increase in plant population densities from 55 thousand to 75 thousand/ha recorded significantly higher plant height, number of leaves per plant at tasseling stage, leaf area, leaf area index, green cob yield and NPK uptake by crop were recorded with the application of fertilizer up to 90 kg N + 45 kg P2O5/ha.

Exploitation of genetic variability for quality traits and agronomic characters in quality protein maize (qpm) germplasm (zea mays l.)

Abstract: The present study was undertaken to identify maize lines having high protein, oil and grain yield at two locations during kharif 2001. Per se performance and genetic behaviour for 14 yield and quality parameters were studied in 169 genotypes. The experiment was laid out in simple lattice design (13x13 structure) with two replications. The analysis of variance revealed significant variability for all the agronomic and quality parameters and thus helped in selection of specific parents for different characters. Among the fourteen characters studied, the genetic advance as per cent of mean along with higher values of heritability, GCV and PVC estimates was maximum for grain yield per plot and protein yield, indicating that, the genetic variance for these two traits are probably due to their high additive gene effects. From 169 genotypes evaluated ten best lines were identified for their good agronomic and quality traits and entry numbers 117, 60 and 69 were found to be highest yielders along with good quality characters, suggesting that, these lines could be utilized in future breeding programme in developing high yielding potential QPM hybirds.

Response of hybrid rice to the application of nitrogen magnesium and boron

Abstract: Response of nitrogen, magnesium and boron along with the recommended dose of phosphorus, potassium were studied on hybrid rice (ProAgro 6201) through a field experiment laid out in split plot design for two consecutive years (2001 and 2002) at Research farm, Department of Agronomy, BHU, Varanasi. Increasing rate of nitrogen, magnesium and boron brought about marked improvement in almost all the yield components of hybrid rice with subsequent decrease in sterility percentage. Consequently significant increase in grain yield as well as profitability was recorded due to incorporation of 180 kg nitrogen, 40 kg magnesium and 2 kg boron ha-1.

Effect of different herbicides on growth and efficacy for weed control in onion (allium cepa l.) seed crop

Abstract: An exerpiment was conducted to study the comparative efficacy of fluchioralin, pendimethalin and oxyflurofen applied alone and along with hand weeding at 45 days after planting (DAP), 3 hand weeding alone given 20, 40 and 60 days after planting (DAP) and unweeded check were carried out. It was concluded that pendimethalin @ 1.0 kg / ha along with a hoeing and weeding at 45 days after planting (DAP) was found most effective and economically viable weed control treatment for onion seed production.

Influence of cropping systems and nutrient management on nutrient uptake, protein content, yield, productivity and net returns of pearlmillet (pennisetum glaucum)

Abstract: Field experiment was conducted to study the effect of cropping systems and nutrient management in pearlmillet on nutrient uptake, quality, yield and net returns. Highest nutrient uptake and protein content were observed with combined application of 60 kg N/ha + 40 kg P2O5/ha + 10 t FYM/ha + biofertilizer. There were no significant influence observed on yield in both the years of experimentation whereas total productivity was found superior with pearlmillet-wheat system and highest net returns also. Among nutrient management practices yield and total productivity was found highest with 60 kg N/ha + 40 kg P2O5/ha + 10 t FYM/ha + biofertilizer while highest net return was obtained with 60 kg N/ha + 40 kg P2O5/ha + 5 t FYM/ha + biofertilizer.

Grain yield, water use efficiency, economics and soil moisture extraction pattern of summer greengram (vigna radiata var. radiata) as influenced by planting and irrigation methods; irrigation schedules and vam inoculation

Abstract: A field experiment was conducted to study the response of summer greengram to the irrigation regimes (two irrigations at pre-flowering and pod filling stages and three irrigations at branching, pre-flowering and pod filling stages), four planting and irrigation methods (flat bed planting and irrigation ridge planting and furrow irrigation, ridge planting and alternate furrow irrigation, furrow planting and irrigation method) and two levels of VAM (control and inoculation). The experiment was laid out in a split plot design with three replications. Greengram cultivar 'Pusa Vishal' produced significantly higher grain yield and had markedly higher net return and benefit: cost ratio under three irrigations, one each at branching, pre-flowering and pod filling stages by furrow planting and irrigation method with VAM inoculation. However, the water use efficiency was higher with two irrigations one each at pre-flowering and pod filling stages. So, an increase in irrigation frequency increased the seasonal water use but decreased the water use efficiency. The higher soil moisture was extracted under two irrigations at pre-flowering and pod filling stages applied by ridge planting and alternate furrow irrigation method without VAM (0-15 cm soil depth).

Effect of irrigation schedules and nitrogen levels on the grain yield of maize in alfisols of nsp left canal command area

Abstract: A field trial was conducted on irrigation schedules and nitrogen levels in maize grown on light red sandy soils of A.R.S., Garikapadu during rabi 1999-2000 to 2001-02 in split plot design. The treatments consisted of four irrigation schedules (0.6, 0.8, 1.0 IW/CPE ratio and 5 irrigations at crop phenological stages in main plots and 5 nitrogen levels (0, 60, 120, 180 and 240 N kg/ha) in sub plots. Grain yield, WUE and nitrogen use efficiency and water requirement were worked out. Maximum grain yield was recorded when the irrigation was scheduled at 1.0 IW/CPE and nitrogen fertilized upto 240 kg/ha.

Effect of phosphorus, potash and rhizobium on pod yield, nutrient uptake and residual available soil npk of vegetable cowpea

Abstract: Field experiments were conducted during 2001 and 2002 at research farm of CARI, Port Blair using Arka Garima variety of vegetable cowpea to study the pood yield, nutrient uptake and residual available soil NPK by various levels of phosphorus potash and Rhizobium inoculation with andwithout nitrogen. The results revealed that maximum average yield of green pods was obtained with the application of 80 kg, P, 120 kg K, 20 kg N/na + Rhizobium inoculation. The length of root, uptake of phosphorus, available phosphorus, and potash in soil was recorded maximum with the application of 120 kg P, 120 kg K and 20 kg N + Rhizobium inoculation.

Effect of tillage and nitrogen levels on growth and yield

Abstract: Experiment was designed in split plot with four replications, three levels of tillage i.e. zero tillage (by using no-till drill), minimum tillage (one ploughing followed by one planking), minimum tillage (one ploughing followed by one planking) and conventional tillage were taken in main plot treatments. Whereas, five nitrogen levels (0, 80, 100, 120 and 140kg/ha) were taken as sub-plots treatments. Various growth and yield attributing factors (viz.plant height, cobs per plant, cob length, grains per cob and 1000 grain weight) were observed. Data on different levels of tillage did not indicate any significant difference for growth, yield attributing characters, grain yield, stover yield and harvest index. Maximum grain yield of 39.5q/ha was recorded in conventional tillage, which was only numericaly different to other treatmetns. But the cost of cultivation was less in case of no tillage, as compared to other tillage treatmetns.

Studies on genetic variability exploitation for quality traits and agronomic characters on quality protein maize (opm) germplasm

Abstract: The present study was undertaken to identify maize lines having high protein, oil and grain yield at two locations. Per se performance and genetic behaviour for 14 yield and quality parameters were studied in 169 genotypes. The experiment was laid out in simple lattice design (13 x 13 structure) with two replications. The analysis of variance revealed significant variability for all the agronomic and quality parameters and thus helped in selection of specific parents for different characters. Among the fourteen characters studied, the genetic advance as per cent of mean along with higher values of heritability, GCV and PCV estimates was maximum for grain yield per plot and protein yield, indicating that the genetic variance had high addive gene effects. From 169 genotypes evaluated ten best lines were identified for their good agronomic and quality characters, suggesting that, these lines could be utilized in future breeding programme in developing high yield potential QPM hybrids.

An analysis of generation means for seed yield and its components in linseed

Abstract: Five generations (P1 P2, F1, F2 and F3) of seventeen linseed crosses, were raised in randomized block design with three replications. The means of the five generations recorded for oil content, seed yield and its contributing traits, were subjected to C-scaling test as suggested by Mather (1949) and fiveparameter model of Hayman (1958) to detect epistasis and estimates of (m), (d), (h), (i) and (1) parameters. There was evidence of epistasis for all the eight traits. Additive gene effect along with epistasis predominantly governed the expression of oil content while non-additive gene effect with epistasis was predominant in number of branches plant-1, number of capsules plant-1 and seed yield plant-1. Days to maturity, number of seeds capsule-1, seed index and harvest index were under the control of both additive and non-additive gene effects together with non-allelic interactions viz., additive x additive and dominance x dominance. A predominance of complementary type of epitasis was observed for number of capsules plant-1, seed yield plant-1, harvest index and oil content followed duplicate type.

Heterosis in long grains aromatic rices for yield and quality components

Abstract: Two CMS lines, IR 68888A and IR68891 A were crossed with six long grains (6.63 to 7.73 mm) aromatic rice varieties and resultant twelve hybrids were evaluated with better parent and standard check, Pusa Basmati-1 for different yield and quality characters. Out of 12, four hybrids exhibited significant negative standard heterosis for days to maturity, whereas out of which one hybrid, IR6888A x PB-5-14-50-1 also showed significant negative standard heterosis for plant height. The heterobeltiosis and standard heterosis for grain yield per plant in hybrids ranged from 11.72 to 89.29% and 18.48 to 104.7%, respectively. Six hybrids exhibited higher degree of heterrobeltiosis and standard heterosis for grain yield. Overall three hybrids viz., IR68888AxPB-6-12-24-4, IR68888AxPB- 5-14-50-1 and IR68888 Ax Hawn Kikwani in the present study were identified superior over standard check for most of the yield and quality characters whereas two hybrids, IR68888xAPB-6-12-24-4 and IR68891AxPB-8-48-59-2 showed high heterosis as well as high outcrossing potential which can be exploited further in hybrid rice breeding programme.

Genetic variability in indigenous cotton (gossypium arboreum) of north eastern region

Abstract: The research work was , undertaken to collect and evaluate arboreum cotton cultivars of N.E.Region of India.The germplasm exhibited significant variation for all the traits along with high estimates of genetic variability and its related parameters. Hence these germplasm could be considered as valuable source of genetic variability for future breeding purposes. Moreover, with the recent trends in globalization of market economy the breeders have to take utmost care for systematic collection, evaluation and maintenance of the indigenous germplasm for the benefit of the farmers and the country as a whole.

Influence of organic and inorganic sources of nutrients on forage productivity and economics of oat (avena sativa l.)

Abstract: A field experiement was conducted at Indian Grassland and Fodder Research Institute during Rabi seasons of 1996-97 to 1998-99 to access the productivity and economics of forage oat with the combined use of organic and inorganic sources of nutrients The treatments comprised of vermicompost 10 t/ha, FYM 10 t/ha, 100% recommended dose of NPK (80:40:0), vermicompost 5 /ha, FYM 5 t/ha, 50% recommended dose of NPK + vermicompost 5 t/ha, 50% recommended dose of NPK + FYM 5 t/ha, 50% recommended dose of NPK (40:20:0) + vermicrompost 5 t/ha + FYM 5 t/ha gave significantly higher green fodder, dry matter and crude protein yields of oat than the other treatments The forage yield exhibited superiority with the treatments where growth parameters attained maximum values However, the results of forage and crude protein yield were comparable with 100% recommended dose of NPK Highest net return (Rs 11575/ha) and benefit: cost ratio (260) was obtained with 100% recommended dose of NPK and was significantly higher than best treatment with regard to forage and crude protein yields ie 50% recommended dose of NPK + vermincompost 5 t/ha + FYM 5 t/ha (114)

Evaluation of yield and quality aspects of indian mustard (brassica juncea l. czernj & cosson) under integrated nutrient management

Abstract: Field experiment was carried out during rabi seasons of 2001-02 and 2002-03 to evaluate the response of Indian mustard cv. RH-30 to farmyard manure (2.5 and 5 t/ha), inorganic N (0,40,80 kg/ha) in combination biofertilizers (Azotobactor chroococcum and Azospirillum). Branches, siliquae/plant, seeds/ siliquae, 1000-seed weight seed oil content and oil yield of Indian mustard and yield of seed and stover. Increased significantly with the application of farmyard manures (5 t/ha + Azotobactor chroococcum + Azospirillum) over the control. Application of N showed liner increase of the characters up to 80 kg/ha.

Stability assessment in late duration rice hybrids

Abstract: Analysis of variance carried out for eight quantitative traits on twenty-five genotypes (twenty-one hybrids and four check varieties) revealed significant genotypic differences at all the five locations for al the traits. Genotypes x location interactions were found to be significant for all the characters except 1000-grain weight. The variance due to genotype x location (linear) was significant only for days to 50% flowering. Non-linear component was found to be significant for all the characters. Among the 25 genotypes studied, only six rice hybrids had given significantly superior yield than populations mean. Out of these, two late rice hybrids viz., IR 58025 A/Karjat 14-7 and IR 68885 A/IR 5 had high potential and showed unit regression coefficient with non-significant non-linear component for grain yield/ha as well as for most of the yield contributing characters and hence suitable for all the environments in Konkan region of the Maharahtra State. While four late rice hybrids viz., IR 58025 A/IR 5, IR 58025 A/Ratnagiri 3, PMS 2 A/Ratnagiri 3 and IR 58025 A/Swarna had high yielding ability and showed significant regression coefficient greater than unity with non-significant no-linear component for grain yield/ha as well for most of the yield contributing characters. Therefore, these hybrids may be suitable in favorable environments only.

Biology of spodoptera litura f. on colocasia esculenta

Abstract: The life cycle of Spodoptera litura F. was completed in shorter period on KCA-1 genotype. The larval, pre-pupal and pupal period were also shorter in KCA-1. The weight and size of larvae and pupae was highest in KCA-1. Similarly, the larval survival, percentage pupation and adult emergence was maximum in KCA-1 as compared to other tested genotype indicating the preference of KCA-1 by Spodoptera litura whereas, the genotype Panch Mukhi was found to be the least preferred genotype by Spodoptera litura among the four tested genotypes of Colocasia esculenta.

Yield components of mothbean (vigna aconitifolia (jacq.) marechal) as influenced by phosphorus and bio-fertilizers

Abstract: A field experiment was conducted to the study the effect of four levels of phosphorus and four biofertilizers. The results showed that application of phosphorus significantly improved the yield attributes viz., number of branches per plant, number of pods per plant, pod length, number of seeds per pod and 1000-grain weight, yield (seed, straw and biological yield), harvest index and benefit: cost ratio of mothbean upto 40 kg P2O5 ha-1 over control and lower doses. Dual inoculation with Rhizobium + phosphate solubilizing bacteria improved the yield attributes, yield and benefit: cost ratio over single inoculation either with Rhizobium or PSB and control. Single inoculation with Rhizobium remains statistically at par with inoculation with PSB, increased the all yield attributes, harvest index and benefit: cost ratio of mothbean over control.

Effect of mixed bio-fertilizers and nitrogen levels on growth, yield attributes and yield of pearlmillet

Abstract: A field experiment was conducted at Research farm of CCS Haryana Agricultural University, Hisar during kharif 2002. Nine treatments viz., control, seed inoculation with mixed bio-fertilizers, 50 RDN, 75% RDN, 100% RDN, 125% RDN, 50% RDN + mixed biofertilizers, 75% RDN + mixed bio-fertilizers and 100% RDN + mixed bio-fertilizers were tested in randomized block design with four replications.Application of 125% RD resulted in significantly higher grain and stover yield except 100% RDN, 75% RDN+mixed bio-fertilizer and 100% RDN+mixed bio-fertilizer. However, stover yield in 75% RDN+mixed bio-fertilizer significantly increased the grain and stover yield over control

Path coefficient analysis for pod yield and its attributes in garden pea (pisum sativum l. sub sp. hortense asch. and garebn.)

Abstract: An experiment was conducted for the physiogenetical analysis of dry matter production and yields in garden pea. Ten genotypes of garden pea, including five early and five mid-season types were studied. The experiment was conducted during the winter seasons of 2002-03 and 2003-04. Data were recorded on different morphophysiological characters. To supplement the information and to have a clear understanding of relationship of different component characters with yield and among themselves, correlation and paths coefficient analysis was carried out. Genotypic path coefficient analyses revealed that number of pods per plant had the highest positive direct effect towards pod yield per plant in both the years. This was followed by other characters like green grain yield per plant, days to first green pod harvest, number of gains per pod and leaf index. Number of pods per plant exerted highest positive indirect effect through leaf area index while highest negative indirect effect was through 1000-seed weight. Shelling percentage followed by characters like biomass weight of plant and harvest index, also exerted direct negative effect. Shelling percentage had highest indirect negative effect through days to first green pod harvest. The study revealed that greater emphasis should be given to characters like number of pod per plant, green grain yield per plant, days to first green pod harvest, number of grains per pod, leaf area index and plant height for green pod yield improvement.

Effect of phosphorus and zinc fertilization on growth and quality of clusterbean [cyamopsis tetragonoloba (l.) taub.]

Abstract: A field experiment was conducted to study the effect of four levels of phosphorus (0, 20, 40 and 60 kg P2O5 ha-1) and five levels of zinc (0, 2.5, 5, 7.5 and 10 kg ha-1). The results showed that application of phosphorus significantly increased plant height, number of branches per plant and dry matter accumulation at harvest, root nodules, and LAI at 45 DAS, chlorophyll content at 30, 45 and 60 DAS and protein and gum content of clusterbean upto 40 kg P2O5 ha-1 over lower doses. Increasing levels of zinc increased the plant height, number of branches per plant, dry matter accumulation, LAI and protein content upto 7.5 kg zinc ha-1 and dry weight of root nodules, gum content and chlorophyll content at 45 and 60 DAS upto 5 kg zinc ha-1, while chlorophyll content at 30 DAS of clusterbean increased upto 2.5 kg zinc ha-1.

Validation and popularization of ipm technology in cotton through farmers participatory approach in tribal area of southern rajasthan

Abstract: The IPM Technology was validated and popularized in village Badgaon, Banswara, Rajasthan through farmers field experiments and farmers fields schools during kharif 2003 and 2004. The IPM module viz., summer ploughing and clean cultivation, early and synchronous sowing of variety G.H.-8, sowing of border trap crop of maize intervene with cowpea all around the cotton field, sowing of setaria in between every 9th and 10th row of cotton which act as a perch crop for birds, installation of pheromone traps all three species of Bollworms @5 traps/ha keeping the height of traps 1 foot above the crop canopy, spray of methyl demeton 25 EC 0.04% at 30 - 35 days after germination, two spray of Neem seed Kernal extract at 45 and 55 days, spray of HaNPV @ 250 LE/ha at 65 DAG, two releases of Trichogramma chilonis @ 1.5 lac/ha at 75 and 85 DAG, need base spray of conventional insecticides was applied in an area of 10 ha field. Farmers field Schools were organized at regular interval to develop the skill and awareness of the farmers about the pests, nature of damage, applicaton of IPM component and natural enemies of the pests. The results of IPM Technology was compared with Non IPM farmers practices which includes 9-10 spray of insecticides. The IPM module reduced the population of sucking insect pests viz., aphids (Aphis gossypii Glover), Jassids (Amrasca bigutulla bigutulla Ishida), White Fly (Bemisia tabaci Genna.), Thrips (Thrips tabaci Lindeman) and bollworms viz., Earias insulana Fab. and Helicoverpa armigera Hub. over non IPM. The mean percent damage to square, flower, green boll, open boll and locule was found less in IPM field as compared to Non IPM fields. The mean seed cotton yield in IPM fields was 1918 and 1804 kg/ha as against 1488 and 1518 kg/ha in non IPM field during 2003 and 2004, respectively. The IPM module also encouraged the population of coccinellids and Chrysoperla carnea and spiders.

Growth dynamics of intercropping system in castor (ricinus communis l.) under irrigated ecosystem

Abstract: A field experiment was conducted to select suitable method of planting and intercropping with castor. Paired row planting of castor (60/120 cm x 60 cm) significantly improved the growth parameters (plant height, DMA, CGR, NAR, LAI), yield attribute (branches plant-1, length of primary spike, capsule plant-1, seed weight plant-1, 100 seed weight) and the yields (seed, stalk and biological). Significantly higher values of growth parameters (plant height at harvest, DMA at 70, 120 and 180 DAS, CGR between 40-70 DAS and 70-120 DAS, LAI and yield attributes were recorded under paired planting of castor with greengram followed by castor+blackgram and castor+clusterbean. Maximum total seed yield and also stalk and biological yields of castor were recorded under castor+greengram intercropping system which was significantly higher over castor+ sesame intercropping system. Significantly higher castor equivalent yield (49.55 q ha-1) was realised under castor+greengram intercropping system over castor+ clusterbean and castor+sesame but found at par with castor+blackgram.

Seasonal fluctuations and extent of losses of brinjal shoot and fruit borer

Abstract: The incidence and intensity of brinjal shoot and fruit borer was studied in relation to different abiotic factors at Kanpur conditions. The period of incidence occurred from2nd week of September to 2nd week of October when 76.66-93.33 per cent plants were found to be infested with an intensity of 1.16-2.90 damaged shoots per plant. Maximum intensity (2.90 shoots/plant) was recorded in the 4th week of September, when the incidence was also maximum (93.33 per cent) and average temperature was 28o C with 75 per cent relative humidity. The initiation of shoot and fruit borer damage on fruits was recorded in the first week of October. Initially the infestation and intensity were high with 1.66 per fruit and 66.66 per cent damage fruit, respectively. The average temperature above 21oC and relative humidity above 65 per cent were found to be more favourable for the pest multiplication. The average losses due to shoot and fruit borer on brinjal fruits were calculated as 13.30 per cent, out of which only 4.83 per cent were found to be totally unconsumable losses.

Effect of nitrogen and mulching on growth and yield of pearlmillet (pennisetum glaucum (l.) r. br. emend. stuntz)

Abstract: A field experiment was conducted during kharif, 2001 at Agronomy farm, SKN College of Agriculture, Jobner (Rajasthan). The treatments comprising of sixteen combinations of four levels each of nitrogen (20, 40, 60 and 80 kg/ha) and mulching (control, dust mulch, mustard straw and Tephrosia purpurea straw) was laid out in a randomized block design and replicated four times. Result indicated that application of 60 N/ ha remaining at par with 80 kg, significantly increased plant height, DM accumulation/m row length and total tillers/plant at 60 DAS and at harvest over 20 and 40 kg N/ha. This treatment also proved superior with respect to number of effective tillers/plant, grain weight/ earhead, grain and straw yield over both the lower levels of nitrogen but the earhead length was significant only over 20 kg N/ha .

Inheritance of fertility restoration of five sources of cytoplasmic male sterility in rice (oryza sativa l.)

Abstract: The cross combinations involving six male sterile lines of five different cytosterile sources viz., IR 58025 A and PMS 2 A (WA), IR 68885 A (Mutant-induced by gamma irradiation of IR 62829 B), IR 54755 A (ARC), G 46 A (Gambiaca) and D 297 A (Dissi), when crossed with five common restores viz., Ratnagiri 3, Swarna, IR 5, IR46 and IR 54, showed more than 80% spikelet fertility restoration in all the combinations except IR 54755 A x Swarna and IR 54755 A x IR 54. The F2 segregation classification based on pollen as well as spikelet fertility in the 28 cross combinations, indicated the presence of two independent dominant fertility-restoring genes. The mode of action of the two genes varied in different crosses revealing three types of interaction viz., epistasis with dominance, epistasis with incomplete dominance and epistasis with recessive. Change in fertility restoration by same restorer with CMS line of same source and different source could be due to the influence of female parent genotype or fertility restoring genes has different penetrance and is affected by modifier.