送交者: dreamer 于 2005-12-07, 18:55:49:
回答: 刘登义说自己在Ecology上发三篇文章说明他连深浅都不知道 由 疫苗 于 2005-12-07, 09:40:40:
Title: Feeding-induced changes in plant quality mediate interspecific competition between sap-feeding herbivores
Author(s): Denno RF, Peterson MA, Gratton C, Cheng JA, Langellotto GA, Huberty AF, Finke DL
Source: ECOLOGY 81 (7): 1814-1827 JUL 2000
Document Type: Article
Language: English
Cited References: 67 Times Cited: 30
Abstract: Feeding-induced plant resistance is a well-documented phenomenon for leaf-chewing insects. Furthermore, feeding-induced resistance provides the mechanistic basis for many cases of delayed interspecific competition, whereby previous feeding by one species diminishes the performance of other herbivores which attack the same plant later in the season. This phenomenon, however, has been very poorly investigated for sap-feeding insects. The results we present here fur salt marsh-inhabiting planthoppers (Prokelisia dolus and P. marginata) provide one of the few known examples of delayed, plant-mediated interspecific competition between two sap-feeding insects.
Three lines of experimental evidence from the laboratory, field cages, and open field plots provide support for the detrimental effects of previous feeding by one planthopper species on the subsequent survival and performance of the other. Laboratory experiments showed that prior feeding on cordgrass by one congener resulted in reduced performance of the other in the following generation. However, the effect was asymmetric. Prior feeding by P. dolus resulted in prolonged development and reduced body size (a correlate of fecundity) in P. marginata, whereas only development was protracted in P. dolus when plants were previously exposed to P. marginata. Consequently, P. dolus appears to be the superior competitor in the context of delayed, plant-mediated interactions. The negative effects of previous feeding by P. dolus on the development time, body size, and survival of P, marginata obtained in the laboratory were confirmed both in cages and on cage-free islets of cordgrass in the field. Feeding-induced reductions in host-plant quality by P. dolus may provide additional impetus for P. marginata to migrate from shared habitats on the high marsh to nutritionally superior plants in the low marsh rarely occupied by P. dolus.
The mechanism underlying the delayed competitive effects between Prokelisia planthoppers is most likely diminished plant nutrition, because feeding by P, dolus significantly reduces the concentration of essential amino acids in cordgrass. The asymmetry of plant-mediated competition between the Prokelisia species may be due to the ability of P. dolus to better tolerate feeding-depleted levels of plant nitrogen via compensatory feeding.
Even though these two planthoppers do not suffer significant fitness reductions during contemporaneous interactions, they compete severely in the context of feeding-induced plant resistance which is expressed later in the season. This result, coupled with the fact that most studies of interspecific interaction between herbivorous insects are contemporaneous, indicates that interspecific competition may be profoundly underestimated as a structuring force in phytophagous insect communities.
Author Keywords: competition, plant-mediated; interspecific competition; intraspecific competition; planthopper; plant nutrition; plant resistance, induced; Prokelisia dolus; Prokelisia marginata; salt marsh; sap-feeding insect; Spartina
KeyWords Plus: PROKELISIA-MARGINATA HOMOPTERA; PUBESCENS-SSP-TORTUOSA; HOST-PLANT; SALT-MARSH; BETULA-PUBESCENS; MOUNTAIN BIRCH; DIMORPHIC PLANTHOPPER; SPARTINA-ALTERNIFLORA; FOLIVOROUS INSECTS; DELPHACIDAE
Addresses: Denno RF (reprint author), Univ Maryland, Dept Entomol, College Pk, MD 20742 USA
Univ Maryland, Dept Entomol, College Pk, MD 20742 USA
Western Washington Univ, Dept Biol, Bellingham, WA 98225 USA
Zhejiang Agr Univ, Dept Plant Protect, Hangzhou, Peoples R China
Title: ACCURACY OF VISIBLE AND ULTRA-VIOLET LIGHT FOR ESTIMATING LIVE ROOT PROPORTIONS WITH MINIRHIZOTRONS
Author(s): WANG ZQ, BURCH WH, MOU P, JONES RH, MITCHELL RJ
Source: ECOLOGY 76 (7): 2330-2334 OCT 1995
Document Type: Note
Language: English
Cited References: 26 Times Cited: 17
KeyWords Plus: GROWTH; DYNAMICS; SOIL
Addresses: WANG ZQ (reprint author), VIRGINIA POLYTECH INST & STATE UNIV, DEPT BIOL, BLACKSBURG, VA 24061 USA
VIRGINIA POLYTECH INST & STATE UNIV, DEPT FORESTRY, BLACKSBURG, VA 24061 USA
JW JONES BIOL RES CTR, NEWTON, GA 31770 USA
NE FORESTRY UNIV, DEPT FOREST SCI, HARBIN, 150040 PEOPLES R CHINA
COWEETA HYDROL LAB, OTTO, NC 28763 USA