Competition between native and immigrant Polygonum congeners

1993 ◽  
Vol 71 (7) ◽  
pp. 939-945 ◽  
Author(s):  
B. Collins ◽  
G.R. Wein
Keyword(s):  
Key Words ◽  
Plant Height ◽  
Biomass Allocation ◽  
Seed Set ◽  
Niche Differentiation ◽  
Greenhouse Experiment ◽  
Competitive Interactions ◽  
Mature Plant ◽  
Shared Resources ◽  
Density Dependent

Coexistence of annual herbs Polygonum punctatum, a native, and Polygonum caespitosum, an immigrant, may result from (i) niche differentiation that reduces or avoids competition, (ii) competitive equivalence for shared resources, or (iii) interaction between a strong competitor and a species that tolerates competition. We investigated competitive interactions between the Polygonum congeners in a greenhouse experiment using plants grown from seed to seed set. Thinning profiles of monocultures were density dependent but did not differ between the species in monocultures. Biomass allocation to root, shoot, and racemes was not influenced by competition from conspecifics or congeners. Mature plant height and raceme production of both species were negatively affected by congener density; however, the species were not competitively equivalent. Polygonum caespitosum was suppressed into the shorter heights in mixture pots but produced more racemes at all but the greatest congener densities. Key words: competition, coexistence, annual herbs, immigrant.

DETERMINATION OF AFTER-RIPENING PERIOD AND HORMONAL RESPONSE OF OROBANCHE SOLMSII C.D. CLARKE SEEDS

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Bista ◽  
G. B. Khattri ◽  
B. D. Acharya ◽  
S. C. Srivastava
Keyword(s):  
Growth Hormone ◽  
Seed Germination ◽  
Key Words ◽  
Incubation Period ◽  
Seed Set ◽  
Summer Season ◽  
Conditioning Period ◽  
Root Parasite ◽  
One Year

To find out the ability of Orobanche seeds to germinate immediately after seed set, seeds were germinated periodically at an interval of three months for one year in GR24. Some Orobanche seeds were capable of germination immediately after seed set but most required about nine months as after ripening or incubation period to be able to germinate. The phenomenon of after ripening in Orobanche seeds could be taken as an ecological measure to dormant over following unfavorable wet summer season. The growth hormone studies on Orobanche seed germination have shown that GA3 at a concentration of 100 ppm substantially enhanced seed germination when applied during pre-conditioning period. NAA showed some stimulatory effect at 0.5 - 1.0 ppm when applied during post-conditioning period but the hormone if applied during pre-conditioning period inhibited the germination. Kinetin failed to stimulate the germination at all the concentrations tested. Key words: Germination, root-parasite, hormone. Ecoprint Vol.11(1) 2004.

PERTUMBUHAN DAN PRODUKSI TANAMAN KACANG TANAH (Arachis hipogea) DAN SENGON (Paraserianthes falcataria) DI ANTARA TANAMAN KELAPA DI SUKABUMI JAWA BARAT

2020 ◽  
Vol 8 (4) ◽  
pp. 126
Author(s):  
HANDI SUPRIADI ◽  
H. T. LUNTUNGAN
Keyword(s):  
Key Words ◽  
Sea Level ◽  
Plant Height ◽  
Soil Type ◽  
Cocos Nucifera ◽  
Cropping System ◽  
Paraserianthes Falcataria ◽  
Number Of Leaves ◽  
Peanut Production ◽  
Female Flowers

<p>Penelitian dilaksanakan pada bulan Januari sampai dengan Desember 2001 di Desa Caringinnunggal, Kecamatan Waluran, Kabupaten Sukabumi, yang bcrada pada kelinggian 250 m di atas permukaan laut, tipe iklim B2 (Oldeman) dan jenis tanahnya Podsolik Merah Kuning. Rancangan yang digunakan dalam penelitian ini adalah rancangan acak kelompok dengan empat ulangan. Perlakuan model polatanam kelapa yang diuji sebagai berikut (1) kelapa + sengon 140 pohon/ha ♦ kacang tanah, (2) kelapa + sengon 280 pohon/ha + kacang tanah, (3) kelapa + sengon 420 pohon/ha ♦ kacang tanah, (4) kelapa + sengon 560 pohon/ha + kacang tanah, (5) kelapa + sengon 700 pohon/ha + kacang tanah dan (6) kelapa monokultur. 'Tujuan dai penelitian ini untuk mcngciahui pertumbuhan dan produksi dari beberapa model polatanam kelapa dengan tanaman sela kacang tanah dan sengon. Pengamatan dilakukan terhadap parameter agronomi meliputi data petumbuhan kacang tanah, sengon dan kelapa seta data produksi kacang tanah. Data yang diperoleh dianalisis dengan menggunakan sidik ragam dan dilanjutkan dengan uji BNJ. Hasil penelitian menunjukkan produktivitas kacang tanah pada polatanam kelapa * sengon 700 pohon/ha + kacang tanah prospektif dengan hasil mencapai 2 183 kg/ha dengan tinggi tanaman 30.25 cm dan polong isi sebanyak 9.65 buah. Sedang untuk tanaman sengon tingginya telah mencapai 312.3 cm dengan diameter 10.57 cm. Adanya tanaman sela diantara kelapa tidak menurunkan pembentukan jumlah daun, jumlah bunga betina dan jumlah tandan tanaman kelapa.</p><p>Kata kunci: Cocos nucifera, Paraserianthes falcataria, Arachis hipogea, polatanam</p><p> </p><p><strong>ABSTRACT</strong></p><p><strong>Growth and producion of peanut and albizia between coconut palms in Sukabumi, West Java</strong></p><p>The study was conducted from January to December 2001 at Caringinnunggal, Sukabumi 250 m above sea level with type of climate Bj according to Oldeman and soil type Red Yellow Podsolic. The expeiment was designed as a randomized block in 4 replicates. The cropping system models consisted of : (1) Coconut + albizia 140 trees/ha ♦ peanut (2) Coconut + albizia 280 trees/ha ♦ peanut. (3) Coconut + albizia 420 trees/ha + peanut, (4) Coconut + albizia 560 trees/ha + peanut, (5) Coconut + albizia 700 trees/ha + peanut and (6) Coconut as a control The purpose of this experiment was to know the growth and productivity of several fanning systems with intercrops in between coconut. The results of the research showed that the peanut production in the cropping system of coconut + albizia 700 trees/ha + peanut reached 2 183 kg/ha, peanut plant height 30.25 cm, mature pods 9.65/plant. While Ihe height of albizia plant reached 3)2.3 cm, stem diameter 10.57 cm. The intercrops planted in between the coconut palms did not reduce the number of leaves, the number of female flowers, and (he number of bunches.</p><p>Key words : Cocos nucifera, Paraserianthes falcataria. Arachis hipogea, cropping system, production</p>

scholarly journals Disturbance‐induced density‐dependent seed set in Shorea siamensis (Dipterocarpaceae), a tropical forest tree

1998 ◽  
Vol 86 (3) ◽  
pp. 462-473 ◽  
Author(s):  
Jaboury Ghazoul ◽  
Katharine A. Liston ◽  
T. J. B. Boyle
Keyword(s):  
Tropical Forest ◽  
Seed Set ◽  
Forest Tree ◽  
Density Dependent

scholarly journals Overexpression of GA 20‐ OXIDASE 1 impacts plant height, biomass allocation and saccharification efficiency in maize

2015 ◽  
Vol 14 (3) ◽  
pp. 997-1007 ◽  
Author(s):  
Wannes Voorend ◽  
Hilde Nelissen ◽  
Ruben Vanholme ◽  
Alex De Vliegher ◽  
Frank Van Breusegem ◽  
...  
Keyword(s):  
Plant Height ◽  
Biomass Allocation ◽  
Saccharification Efficiency

scholarly journals combining ability for yield and yield contributing characters of white jute (Corchorus capsularis L.)

1970 ◽  
Vol 39 (1) ◽  
pp. 79-85
Author(s):  
Rahima Khatun ◽  
RH Sarker ◽  
MA Sobhan
Keyword(s):  
Key Words ◽  
Plant Height ◽  
Combining Ability ◽  
Reciprocal Cross ◽  
General Combining Ability ◽  
Predominant Role ◽  
Base Diameter ◽  
Corchorus Capsularis ◽  
Additive Gene ◽  
Fibre Yield

Crosses were made between three varieties and seven accessions of white jute (Corchorus capsularis L.) in all possible combinations to establish 10 × 10 full diallel set. Variances for general combining ability (GCA) and specific combining ability (SCA) were significant or highly significant for all the characters indicating additive and non-additive gene actions played predominant role for expression of these characters. The magnitudes of GCA variance were higher than the corresponding SCA variance confirmed the predominance of additive genetic variations for these traits. The variety CVL-1 and Acc. 1831 were good general combiners for plant height, technical height, base diameter, number of nodes, bark weight, fibre weight and stick weight. Crosses, var. CVL-1 × Acc. 1831, Accs. 3695 × 4087, Accs. 1831 × 1833, Accs.1831 × var.CC-45, Acc. 2146 × var. A-38 and Acc. 2146 × var.CC-45 revealed significant positive SCA effect for fibre weight. Significant reciprocal SCA effect was observed in crosses, Accs.1832 × 3695, Accs.1833 × 1831 and Acc. 4087 × var.CVL-1. Crosses, var. CVL-1 × Acc.1831, Accs. 3695 × 4087, Acc.1831 × var.CC-45, Acc.2146 × var.CC-45 and a reciprocal cross, Accs.1833 × 1831 were found to be good specific combiners for bark weight, fibre weight and stick weight. Key words: Combining ability; Fibre yield; White jute DOI: 10.3329/bjb.v39i1.5530Bangladesh J. Bot. 39(1): 79-85, 2010 (June)

The consequences of mixed pollination on seed set in Vaccinium corymbosum

1991 ◽  
Vol 69 (11) ◽  
pp. 2448-2454 ◽  
Author(s):  
S. P. Vander Kloet
Keyword(s):  
Key Words ◽  
Seed Set ◽  
Vaccinium Corymbosum ◽  
Viable Seed ◽  
Maturation Time ◽  
Embryo Abortion ◽  
Berry Ripening ◽  
Time Required ◽  
Compatible Pollen ◽  
Berry Maturation

Self pollen of Vaccinium corymbosum germinates as well as outcross (compatible) pollen from the same population and more rapidly than compatible pollen from more distant populations. When a mixture of self and compatible pollen, either from the same or incontiguous populations, is applied to the stigma, the time required for berry ripening is significantly reduced compared with compatible pollen alone, although seed set also decreases significantly. Adding compatible pollen from different pollen donors significantly increased seed set but also increased the time for berry maturation by 5 days. Self pollen in conjunction with compatible pollen resulted in a 50% loss of viable seed production and an 8% gain in berry maturation time. Self-pollination resulted in embryo abortion in V. corymbosum. Key words: pollination, Vaccinium, seed set, outcrossing.

scholarly journals Simulated mesotrione drift followed by glyphosate, imazethapyr, bentazon or glyphosate plus chlorimuron in soybean

2009 ◽  
Vol 89 (2) ◽  
pp. 265-272
Author(s):  
L. R. Brown ◽  
D. E. Robinson ◽  
K. Chandler ◽  
C. J. Swanton ◽  
R. E. Nurse ◽  
...  
Keyword(s):  
Glycine Max ◽  
Key Words ◽  
Plant Height ◽  
Seed Yield ◽  
Plant Density ◽  
Dry Weight ◽  
Shoot Dry Weight ◽  
Glycine Max L ◽  
Herbicide Drift

There have been anecdotal accounts of increased crop sensitivity due to herbicide drift followed by an in-crop herbicide. An experiment was conducted from 2005 to 2007 at Elora, Ridgetown, and Woodstock, Ontario, to determine the effects of simulated mesotrione drift followed by in-crop applications of glyphosate, imazethapyr, bentazon and glyphosate plus chlorimuron on glyphosate-resistant soybean [Glycine max (L.) Merr.] visual injury, plant height, plant density, shoot dry weight, and seed yield. As the rate of simulated mesotrione drift increased, there was an increase in soybean injury and a decrease in shoot dry weight, height, and yield. Simulated mesotrione drift followed by bentazon resulted in synergistic responses in injury shortly after application in some environments. This increase in injury was transient, with no synergistic responses in density, shoot dry weight, and yield. In contrast, antagonistic responses were observed when glyphosate, imazethapyr, or glyphosate plus chlorimuron were applied after simulated mesotrione drift in some environments. Further research is required to develop a better understanding of the interactions of drift followed by the application of an in-crop herbicide. Key words: Bentazon, chlorimuron, glyphosate, imazethapyr, mesotrione, synergism

Testing for Density-Dependent Marine Survival in Pacific Salmonids

1978 ◽  
Vol 35 (11) ◽  
pp. 1434-1450 ◽  
Author(s):  
Randall M. Peterman
Keyword(s):  
Survival Rate ◽  
Key Words ◽  
Survival Data ◽  
Statistical Tests ◽  
Frequency Of Occurrence ◽  
Density Dependent ◽  
Key Words Density ◽  
Marine Survival ◽  
Pacific Salmonids

Marine survival data for several different salmonid stocks were reviewed to determine whether there was significant density-dependent survival occurring in the ocean. Four classes of interaction were examined: (1) within-cohorts, (2) between-cohorts, (3) between stocks on the same or nearby rivers, and (4) between stocks of distant rivers. Results of statistical tests indicate that some stocks do not produce an increase in adult returns with increased smolt abundance, and that marine survival rate of other stocks is affected by abundance of other cohorts or stocks. Only a few stocks exhibit these density-dependent relations, but given present data, it is impossible to predict the frequency of occurrence of such limiting processes in future enhanced stocks. Salmonid enhancement planning is discussed in the context of this uncertainty and experimental enhancement projects are suggested that aim to obtain information about marine survival processes as well as additional catches. Key words: density dependent, marine survival, salmonids, experimental enhancement, stock interaction, adaptive

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