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261.
Krishna Murari Sharma Deendayal Sharma Shiv Singh Tomar Ganpat Singh Chauhan 《Archives of Agronomy and Soil Science》2013,59(1):61-71
A field experiment was conducted during the winter seasons between 2004 and 2006 to assess the role of balanced fertilization and bioregulators (foliar-applied brassinosteroid 0.5 mg I?1, thiourea 1000 mg I?1 and kinetin 10 mg I?1) in enhancing the productivity of wheat. Conjoint application of NPKSZn (120 kg N, 40 kg P2O5, 30 kg K2O, 40 kg S, 5.5 kg Zn ha?1) recorded maximum improvements in yield attributes and significantly out-yielded all the fertilization treatments with 14.90, 4.97 and 6.39% increments in grain yield compared with NPK, NPKS and NPKZn treatments, respectively. Nutrient (N, P, K, S, Zn) content and uptake were also improved significantly with balanced fertilization. Among the bioregulators, application of 0.50 mg I?1 brassinosteroid recorded maximum increments in grain yield (14.10%), followed by 10 mg I?1 kinetin (12.31%) and 1000 mg I?1 thiourea (9.92%), over control (4.99 t ha?1). Bioregulators significantly enhanced the uptake of nutrients (N, P, K, S, Zn) over control. NPKSZn treatment also gave the maximum net return (Rs. 51,209 ha?1). Among the bioregulators, brassinosteroid provided the maximum net return (Rs. 47,292 ha?1) and benefit:cost (B:C) ratio (3.37) followed by thiourea (Rs. 45,500 ha?1 and 3.35). Kinetin also provided yield advantage, however, it gave a significantly reduced B:C ratio compared with control. 相似文献
262.
Krishna Prasad Woli Toshiyuki Nagumo Ryusuke Hatano 《Soil Science and Plant Nutrition》2013,59(6):883-887
Abstract This study was conducted to evaluate the magnitude of nitrogen (N) pollution in stream water associated with intensive livestock farming practices. An extensive water sampling was carried out from stream tributaries, open channels, drainages, and seepages during the snow-melting season in 2001. Total nitrogen (TN) concentration was determined and water flow was measured. The lowest concentration of TN in the headwater of tributary ‘A’ was as low as 0.39 mg N L?1 (0.03 g s?1 of N load), and the concentration reached a value of 5 mg N L?1 in the outlet of the stream, which resulted in a N load of 1.37 g s?1. The increase in the N load (1.34 g s?1) was mainly due to drainage from a constructed wetland for livestock wastes, other drainages, and seepages from around the livestock sheds. The maximum concentration of TN in the drainage and seepage water from the constructed wetland was very high, 63 mg N L?1, which resulted in a N load of 0.53 g s?1 into the open channel that reached tributary ‘A.’ About 40% of the increased N load in the main tributary in the intensive livestock farming area was occupied by a single constructed wetland confirming that the drainage from this facility acted as the point source of pollution in the area. 相似文献
263.
Rearing ofEpiricania melanoleuca (Fletcher) on adult females ofPyrilla perpusilla (Walker) augmented the productivity of the former, which is an effective nymphal and adult ectoparasitoid of the latter, in terms of yield of total and viable eggs. The applied value of this finding in field biocontrol program is highlighted.
With one table 相似文献
Zusammenfassung Wurden die ektoparasitischen Raupen vonEpiricania melanoleuca auf adulten Weibchen der Zuckerrohr-Zikade,Pyrilla perpusilla aufgezogen, vergrößerte sich die Zahl und Lebensfähigkeit der Eier, die von den daraus resultierenden Faltern abgelegt wurden. Das Ergebnis wird im Hinblick auf einen Einsatz des Parasitoiden zur biologischen Bekämpfung des Schädlings erörtert.
With one table 相似文献
264.
M N Krishna Murthy S Rajalakshmi J A Satyabodha K V Nagaraja 《Journal of the Association of Official Analytical Chemists》1991,74(4):698-699
A simple and precise method of detecting brominated vegetable oil (BVO) in soft drinks is described. After extraction of BVO using diethyl ether, the concentrated ethereal solution was treated with a small quantity of zinc dust to convert the organic bromide to inorganic form; the solution was subsequently treated with lead dioxide to liberate bromine. The bromine evolved was detected by means of fluorescein-impregnated filter paper strip that turns pink because eosin is formed. The test can detect as low as 10 ppm (2 mg/200 ml) of BVO under experimental conditions. Gas chromatography was carried out on sodium methoxide derivatives prepared from ether extract for quantitation. 相似文献
265.
G Nageswara Rao P Mahesh Kumar V S Dhandapani T Rama Krishna T Hayashi 《Fitoterapia》2000,71(1):82-83
The isolation and spectral data of di-(2-ethyl) hexyl phthalate (1) from Cassia auriculata leaves are reported. 相似文献
266.
Krishna D. Joshi Attiq U. Rehman Ghullam Ullah Mian F. Nazir Mahreen Zahara Jamil Akhtar 《Journal of Crop Improvement》2017,31(4):608-627
We conducted this research because earlier research revealed that Pakistani farmers were growing 8–10-year-old wheat (Triticum aestivum L.) varieties and hence not benefitting from the recent advances in wheat breeding. Participatory varietal selection (PVS) trials were conducted to have farmers validate and include newly released wheat varieties into seed-production stream to speed up replacement of old and obsolete wheat varieties by farmer-preferred new high-yielding varieties. Fourteen new varieties recommended for irrigated and eight for rainfed environments were evaluated in this research involving smallholder farmers in food-deficit districts of Pakistan. Collaborating farmers preferred 10 varieties from the PVS trials, eight of which were germplasm from the International Maize and Wheat Improvement Center (CIMMYT) that yielded on average 5–17% more grain than local checks. Local checks used in the PVS trials in Sindh and Khyber Pakhtunkhwa were old improved varieties. Greater yield advantage from new varieties over local checks was reported from rainfed environments and areas where old local checks were used. The PVS research showed the possibility of ensuring food security of smallholder farmers as new high-yielding varieties gave an additional 0.3 –0.5 tons of grain per ha, sufficient to feed two to three persons per year. Research also revealed that innovative farmers in rainfed regions grew wheat varieties recommended for irrigated regions to identify high-yielding wheat varieties with stable performance. Feedback by farmers to wheat breeding research system was to develop even higher yielding new wheat varieties with diseases resistance to replace old and obsolete varieties to boost food security. 相似文献
267.
German V. Sandoya Suraj Gurung Dylan P. Short Krishna V. Subbarao Richard W. Michelmore Ryan J. Hayes 《Euphytica》2017,213(1):20
Race 1 resistance against Verticillium dahliae in lettuce was originally shown in the cultivar La Brillante to be conditioned by a single dominant gene (Verticillium resistance 1, Vr1). Multiple, morphologically diverse sources of germplasm have been identified as resistant to race 1. In this study, allelism tests indicated that resistance in these different lettuce cultivars is closely linked or allelic to the Vr1 gene. The Vr1 gene is defeated by race 2 isolates of V. dahliae. Only partial resistance to race 2 isolates is available in a few plant introductions (PIs). Greenhouse and field experiments conducted with these PIs demonstrated partial resistance to V. dahliae race 1 as well as race 2 isolates from lettuce. Cultivars resistant to race 1 and PIs with partial resistance to race 2 were challenged with several race 1 and 2 isolates originating from hosts other than lettuce. This indicated that cultivars resistant to race 1 and the breeding lines derived from them would also be resistant to race 1 isolates from other hosts; similarly, the partial resistance would be effective against race 1 and 2 isolates from hosts other than lettuce. Nevertheless, there were specific interactions that warrant further study. Although race 1 currently predominates in the major lettuce production area of the Salinas Valley, CA, breeding lettuce for resistance to V. dahliae should take both races into account. 相似文献
268.
Unraveling the mystery of Indian monsoon failure during El Niño 总被引:1,自引:0,他引:1
The 132-year historical rainfall record reveals that severe droughts in India have always been accompanied by El Ni?o events. Yet El Ni?o events have not always produced severe droughts. We show that El Ni?o events with the warmest sea surface temperature (SST) anomalies in the central equatorial Pacific are more effective in focusing drought-producing subsidence over India than events with the warmest SSTs in the eastern equatorial Pacific. The physical basis for such different impacts is established using atmospheric general circulation model experiments forced with idealized tropical Pacific warmings. These findings have important implications for Indian monsoon forecasting. 相似文献
269.
Drought is becoming an increasingly important constraint limiting world''''s rice production 《分子植物育种》2007,5(2):213-214
Drought is becoming an increasingly important constraint limiting world's rice production (Bennett, 2003). About half of the world's rice is grown in ralnfcd environments where the rainfall is the major source of water supply, and yields may be seriously restricted by water deficit. Drought tolerance, though a complex character resulting from many interacting component traits, depends mainly on root characteristics of the rice plant that directly affects the quantity of water available to the crop in the dry season. 相似文献
270.
Spray retention and foliar washoff of imazaquin in smooth pigweed (Amaranthus hybridus L.) and sicklepod (Senna obtusifolia (L.) Irwin and Barneby) were investigated. Imazaquin (70 g AI ha−1) was applied alone, with nonionic surfactant ‘X-77’ or organosilicone-based nonionic surfactant ‘Kinetic’ to plants at two- to five-leaf stage and subjected to 2·5 cm rainfall in 20 min either 1 or 24 h after application. Imazaquin spray retention was higher with adjuvants than without. Retention was similar between adjuvants in smooth pigweed but ‘Kinetic’ retained twice as much imazaquin as ‘X-77’ in sicklepod. Rainfall 1 h after application washed off three-quarters of foliar residues regardless of plant species or adjuvant. However, at 24 h after application, foliar washoff was lowest with ‘Kinetic’ followed by ‘X-77’ in both species. Imazaquin washoff ranged from 33 to 88% in the two species at 24 h after application. Overall, imazaquin activity was similar with either adjuvant in smooth pigweed but ‘Kinetic’ was more effective than ‘X-77’ in sicklepod. Runoff losses from the surface of a Bosket sandy loam (Mollic Hapludalfs) soil in runoff trays (1·2% slope) were also studied. Imazaquin was applied as above to trays with and without smooth pigweed canopy. A 2·5-cm rainfall was applied in 20 min at 24 h after application. Runoff samples collected in one-litre fractions were analyzed by enzyme-linked immunosorbent assay. Sediment (but not water) in runoff was greatly reduced (56%) by pigweed cover as compared to bare trays. Imazaquin in the first litre of runoff was higher than in subsequent runoff fractions regardless of pigweed cover. Total imazaquin lost in runoff was higher in pigweed cover (23%) than bare trays (16% of applied). Imazaquin concentration in 10–20 cm soil depth in pigweed cover trays was higher than in bare trays. These results suggest that imazaquin is vulnerable to foliar washoff and the herbicide washed off could move in the aqueous phase due to shorter contact time with soil for sorption. 相似文献