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151.
Supplementing the nutrient requirement of crops through organic manures plays a key role in sustaining soil fertility, and crop productivity and reducing use of fossil fuels. Field experiments were conducted for 2 years at two different locations (i.e. Lucknow and Pantnagar) in Uttar Pradesh, India. The objectives of the study were to assess the herb and essential oil yields of Japanese mint (Mentha arvensis cv. Hy 77), and its nutrient accumulation under single and combined applications of organic manures and inorganic fertilizers (NPK). Changes in physical and chemical characteristics of the soils (Fluvisols, Mollisols) were also determined. Eight treatments comprising different combinations of NPK through inorganic fertilizers and farm yard manure (FYM) were compared. The distilled waste of mint after extraction of essential oil was recycled to soils in the plots to supplement the nutritional requirement of the succeeding mustard crop (Brassica juncea cv. Pusa Bold). Herb and essential oil yield of mint were significantly higher with combined application of organic and inorganic sources of nutrients as compared to single applications. Accumulation of N and P was at par under full inorganic and combined supply whereas, K accumulation was higher with the former. Soil organic C and pH after harvest of mint did not significantly differ among the treatments, but the level of mineralizable N, Olsen-P and NH4OAc extractable K were higher in soil with integrated supply of nutrients. Significant increase in soil water stable aggregates, organic C, available NPK and microbial biomass, and decrease in soil bulk density were observed with waste recycling over fertilizer application. These benefits were reflected in the seed and stubble yield of mustard which succeeded mint. This study indicates that combined application of inorganic fertilizers with organics helps in increasing the availability of nutrients and crop yield and provides a significant effect to the succeeding crop. Similarly, recycling crop residues reduces the need for fossil fuel based fertilizer, and helps in sustaining and restoring soil fertility in terms of available nutrients and major physical and chemical characteristics of the soil. 相似文献
152.
Nectar acquisition in the honeybee Apis mellifera is a partitioned task in which foragers gather nectar and bring it to the hive, where nest mates unload via trophallaxis
(i.e. mouth-to-mouth transfer) the collected food for further storage. Because forager mates exploit different feeding places
simultaneously, this study addresses the question of whether nectar unloading interactions between foragers and hive-bees
are established randomly, as it is commonly assumed. Two groups of foragers were trained to exploit a different scented food
source for 5 days. We recorded their trophallaxes with hive-mates, marking the latter ones according to the forager group
they were unloading. We found non-random probabilities for the occurrence of trophallaxes between experimental foragers and
hive-bees, instead, we found that trophallactic interactions were more likely to involve groups of individuals which had formerly
interacted orally. We propose that olfactory cues present in the transferred nectar promoted the observed bias, and we discuss
this bias in the context of the organization of nectar acquisition: a partitioned task carried out in a decentralized insect
society. 相似文献
153.
E. Lamla F. Boschke G. Traving G. Pfotzer H. Wolter W. Walcher H. D. Dahmen H. J. Queisser W. W. Klingbeil K. Beyermann O. Müller R. R. Ernst D. Reinen H. Muth W. Becker G. Wunsch G. I. Distler L. Jaenicke H. G. v. Schnering H. Werner F. Reiff H. Schimassek W. Höll H. K. Vasil W. F. Angermeier W. Ruppel J. C. Eccles G. Spiteller H. Oettel W. Vogell P. Brosche K. J. Hsü H. -U. Schmincke 《Die Naturwissenschaften》1975,62(3):143-143
154.
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159.
P.D.Whanger 《环境科学学报(英文版)》1996,8(3):328-340
Seleniummetabolisminanimalsandhumans¥P.D.Whanger(DepartmentofAgriculturalChemistry,OregonUniversity,Oregon97331-7301,USA)Abst... 相似文献
160.
Konstantinos D. Stagiannis Dr Waldo Sepulveda Luca Fusi Christine Garrett Nicholas M. Fisk 《黑龙江环境通报》1995,15(1):70-73
Exencephaly was diagnosed at 17 weeks in a 27-year-old primigravida with abnormalities of the hands and a family history suggestive of autosomal dominant brachydactyly and clinodactyly. In this family there was also a history of ‘anencephaly’. To our knowledge, this is the first report on the association of exencephaly and autosomal dominant brachydactyly. As the relationship between hand and cranial anomalies is well established, we suggest that this association in our case could be due to a defect in the same gene. 相似文献