scholarly journals What mechanisms are involved in cabbage-clover intercropping and a further proof of the 'host plant quality' hypothesis

2000 ◽  
Vol 6 (4) ◽  
Author(s):  
Z. Seress ◽  
R. G. McKinlay ◽  
B. Pénzes ◽  
K. Sezák
Keyword(s):  
Growth Rate ◽  
Host Plant ◽  
Relative Growth Rate ◽  
Field Trials ◽  
Plant Quality ◽  
Host Plant Quality ◽  
Relative Growth ◽  
Mean Relative Growth Rate ◽  
The Mean ◽  
Aphid Populations

Over 10 years of field trials show reductions of most of the pests in Brassicas undersown by clover. The pest-reducing effects are due to the 'appropriate / inappropriate landings' hypothesis (Finch, 1996), and the 'host plant quality' hypothesis (Theunissen, 1994). To find out the mechanisms within the 'host plant quality' hypothesis in the most promising intercropping (collards undersown by clover) glasshouse experiments were conducted to see whether intercropping influences the mean relative growth rate, fecundity and time of maturity of Myzus persicae (Sulzer) (Homoptera: Aphididae) a common pest of Brassicas. The treatment modelling intercropping showed the smallest mean relative growth rate, delayed the maturity and slowed down the growth of cabbages. The treatment modelling monocropping showed the highest mean relative growth rate and the maturity was reached earlier. These results may indicate that intercropping delays the growth of settled aphid populations, giving another proof that in the case of clover undersown cabbages the 'host plant quality' hypothesis is likely to be acting. The differences between treatments where the roots of clover and cabbages were separated and allowed to grow together suggest that the effect is via the roots by competition.  

scholarly journals THE EFFECT OF MID-SEASON VINE REMOVAL ON THE GROWTH OF FIVE SWEETPOTATO (IPOMOEA BATATAS L.) CULTIVARS

HortScience ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 266E-266
Author(s):  
Victor A. Kahn ◽  
C. Stevens ◽  
T. Mafolo ◽  
C. Bonsi ◽  
J.Y. Lu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Assimilation Rate ◽  
Marketable Yield ◽  
Relative Growth ◽  
Crop Growth Rate ◽  
Mean Relative Growth Rate ◽  
The Mean ◽  
Net Assimilation

TU-82-155 and `Georgia-Jet' early maturing. `Carver II', TU-1892 and `Rojo-Blanco' late maturing sweetpotato, cultivars were evaluated in the field for 0.20 and 40% vine removal (VR) at 8 wk after transplanting. Parameters measured were: leaf area index (LAI) recovery, net assimilation rate, foliage crop growth rate (FCGR), storage roots crop growth rate (RCGR). alpha a (the mean relative growth rate in dry wt to the mean relative growth rate in leaf area over a time interval) or the partitioning of assimilates, total and marketable yield. A split. splitplot design was used and plants were sampled at 3 and 8 wk following VR. Except for TU-82-155 all cultivars showed significant LAI recovery above the control at 3 and 8 wk after vine removal when 20% of the vines were removed while at the 40% VR, only 'Georgia-Jet'. TU-1892 and 'Carver II' showed significant increases in LAI for the same periods. Net assimilation rate showed significant interactions while FCGR was not significantly affected by either 20 or 40 VR compared to the control at 3 or 8 wk after VR. RCGR was significantly affected by both levels of VR at 3 and 8 wk after VR and surplus assimilates (alpha a) showed significant interactions between cultivars and % VR. Told yield declined for all cultivars irrespective to maturity groups with the sharpest decrease being at the 20% VR. All cultivars except TU-82-155 showed a decrease in marketable yield, the increase in marketable yield of TU-82-155 was due to a lower non-marketable yield.

Low temperature effects on the growth of evening primrose (Oenothera spp.) rosettes

2004 ◽  
Vol 52 (1) ◽  
pp. 19-28
Author(s):  
A. F. Fieldsend
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Relative Rate ◽  
Field Trials ◽  
Effect Of Temperature ◽  
Relative Growth ◽  
Evening Primrose ◽  
Intermittent Exposure ◽  
Environment Experiment

In field crops of evening primrose (Oenothera spp.) the post-winter growth of rosettes is slow to re-start. The effect of temperature on the growth of rosettes was assessed in a controlled environment experiment. Relative growth rate was positively correlated with temperature, but in apparent contrast to the results from field trials, the rosettes grew at constant temperatures as low as 6.5ºC. However, following transfer to warmer temperatures an increase in relative growth rate did not occur until 7-10 days later, whilst a change to a cooler environment caused an immediate reduction in relative growth rate. Thus, it seems likely that growth is inhibited by intermittent exposure to temperatures of 0°C or below. Partitioning of biomass between root and shoot was independent of temperature, but at 6.5ºC the relative rate of leaf area increase was very low. Consequently, the specific leaf area was lower in rosettes growing at lower temperatures.

scholarly journals BUDIDAYA BEBERAPA VARIETAS IKAN SEPAT RAWA (Trichogaster trichopterus Pall) DENGAN PEMBERIAN PAKAN KOMERSIAL (SOME VARIETY AQUACULTURE THREE SPOT GORAMY (TRICHOGASTER TRICHOPTERUS PALL) WITH THE PROVISION OF COMMERCIAL FEED)

2016 ◽  
Vol 1 (2) ◽  
pp. 214 ◽  
Author(s):  
Akhmad Murjani
Keyword(s):  
Growth Rate ◽  
Tidal Marshes ◽  
Average Growth Rate ◽  
Average Growth ◽  
Relative Growth ◽  
Growth And Survival ◽  
Commercial Feed ◽  
Mean Relative Growth Rate ◽  
The Mean ◽  
Cultivation Environment

Tujuan dari penelitian ini adalah untuk menentukan kecepatan pertumbuhan dan kelangsungan hidup tiga jenis ikan gurami (Trichogaster trichopterus, Pall) di rawa monoton, rawa pasang surut, dan rawa tadah hujan yang dipelihara di hapa Galam.Tiga jenis ikan gurami (Trichogaster trichopterus, Pall) mampu hidup dan beradaptasi di lingkungan budidaya, dan dapat diberi makan dengan pakan buatan seperti ikan budaya. Variasi jenis ikan tidak  signifikan mempengaruhi pertumbuhan rawa dan kelangsungan hidup ikan yang dipelihara di lingkungan budidaya rawa. Tingkat pertumbuhan berat rata-rata relatif terbaik adalah perlakuan C (ikan  gurami rawa tadah hujan) sebesar 29.36%. Tingkat pertumbuhan pangjang rata-rata relatif terbaik adalah perlakuan B (Ikan gurami padang rumput rawa) sebesar 9,35%. Konversi pakan terbaik terdapat pada perlakuan C (ikan gurami dari tadah hujan) sebesar 6.80. Tingkat keangsungan hidup terbaik terdapat pada perlakuan B, C, D yaitu sebesar 75.56%.The purpose of this study was to determine the speed of growth and survival of several varieties of three spot goramy (Trichogaster trichopterus Pall) from the monotonous marshes, tidal marshes, bogs and swamps rainfed fields that are kept in hapa Galam.Three spot goramy (Trichogaster trichopterus Pall) are able to live and adapt in the cultivation environment, and can be fed with artificial feed like most culture fish. Variations in the type of fishes did not significantly affect marsh growth and survival of fish that are kept in swamp ride cultivation environment. The mean relative growth rate of weight it is best to treatment C (fish from the marsh three spot goramy rainfed) of 29.36%. Average growth rate is relatively long it is best to treatment B (three spot goramy of marsh meadow Galam) for 9.35 %. Conversion is best to feed on the C treatment (fish from the marsh three spot goramy rainfed) of 6.80. the best survival was in treatment B, C, D of 75.56%.

Scientometric Analysis of Vikalpa: The Journal for Decision Makers (2008-2017)

2019 ◽  
Vol 9 (S1) ◽  
pp. 5-11
Author(s):  
C. Suresh ◽  
V. Ramesh Babu
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Decision Makers ◽  
Total Output ◽  
Scientometric Analysis ◽  
Research Activity ◽  
Authorship Pattern ◽  
Relative Growth ◽  
Author Paper ◽  
The Mean

This study aims to present a scientometric analysis of the journal titled vikalpa: the journal for decision makers” for the period from 2008 to 2017. The present study was conducted with an aim to provide a summary of research activity in the current journal and characterize its most important aspects. The analysis covers mainly the year wise distribution of articles, category wise classification of papers, authorship patterns of papers, the degree of collaboration, most prolific contributions of papers, institution-wise distribution of contributions and geographical distribution of papers of the journal. The analysis showed that 325 papers were published in the journal of vikalpa: the journal for decision makers” for the period from 2008 to 2017. The maximum number of publication was recorded in 2014 (39 articles, 12.00%) while the minimum was in the year 2017 (21 articles, 6.46%). The authorship pattern was studied to determine the percentage of single and multiple authorship. It is observed from the study that a single author 114(35.08%) paper occupied the 2nd rank. Two author paper 132(40.62%) occupied in 1st rank. Three author paper 41 (12.62 %) occupied in 3rd rank and more than three author paper 38(11.69%) occupied in 4th rank. The study exposes that during 2008-17 the highest proportion of papers were by single authors 114 followed by papers with two authors 211, and more than three authors 325. Among the ten years of the study period, the highest degree of collaboration occurred in the year of 2012. The growth rate is 0.72 in 2008 and which decreased up to 0.07 in 2017. The mean relative growth rate for the periods of 2008 to 2017 the relative growth rate of 0.223. This study period resulted that the mean doubling time for total output 4.088 years. It is observed from the study that the highest number of contributors is belonging to India with 270 articles out of 325 total articles published and its percentage is 83.08 %.

Growth Responses of Tanoak Sprout Clumps to Thinning

1994 ◽  
Vol 9 (4) ◽  
pp. 101-105 ◽  
Author(s):  
Timothy B. Harrington
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Growth Responses ◽  
Relative Growth ◽  
Vegetation Height ◽  
Crown Width ◽  
Lithocarpus Densiflorus ◽  
Mean Relative Growth Rate ◽  
Relative Cover ◽  
Second Year

Abstract At two sites in southwestern Oregon, stands of tanoak (Lithocarpus densiflorus) were thinned in the second year after sprouting (1983) to create relative covers of 25, 50, or 100% of that for unthinned stands. At one site, relative covers were replicated with and without suppression of understory vegetation. Height, crown width and dominant-stem diameter were measured annually on each of 135 sprout clumps of tanoak from 1983-1988. Reductions in relative cover caused a proportionate increase in mean relative growth rate (RGR) of tanoak; however, the effect of understory suppression was not consistent. Increases in RGR of individual clumps from thinning were considerably greater for crown width (73% and 43% for large and small clumps, respectively) than for height (28% and 22%). Predicted crown width of tanoak 6 yr after thinning and understory suppression was up to 46% greater than that of clumps in untreated stands. West. J. Appl. For. 9(4):101-105.

scholarly journals Response of Insect Relative Growth Rate to Temperature and Host-Plant Phenology: Estimation and Validation from Field Data

PLoS ONE ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. e86825 ◽  
Author(s):  
Mamadou Ciss ◽  
Nicolas Parisey ◽  
Gwenaëlle Fournier ◽  
Pierre Taupin ◽  
Charles-Antoine Dedryver ◽  
...  
Keyword(s):  
Growth Rate ◽  
Host Plant ◽  
Relative Growth Rate ◽  
Field Data ◽  
Plant Phenology ◽  
Relative Growth

scholarly journals GROWTH ANALYSIS OF FIVE SWEETPOTATO (IPOMOEA BATATAS L) CULTIVARS

HortScience ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 267E-267
Author(s):  
Victor A Khan ◽  
C. Stevens ◽  
T. Mafolo ◽  
C. Bonsi ◽  
J.Y. Lu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Crop Growth Rate ◽  
Early Maturing ◽  
Mean Relative Growth Rate ◽  
The Mean ◽  
Net Assimilation ◽  
Maturity Groups

TU-82-155 and `Georgia-Jet' early maturing. `Carver II'. TU-1892 and `Rojo-Blanco' late maturing sweepotato cultivars were evaluated in the field for: leaf area index (LAI), net assimilation rate, foliage crop growth rate (FCGR), storage roots crop growth rate (RCGR) and alpha a (the mean relative growth rate in dry wt to the mean relative growth rate in leaf area over a time interval) or the partitioning of assimilates. A split plot design was used and plants were sampled at 6, 8, 11 and 16 wk after transplanting. The results from study showed that LAI reached maximum development 8 and 12 wk after transplanting for early and late maturing cultivars, respectively. All cultivars irrespective to maturity groups showed a reduction in net assimilation rate 6 wk after transplanting while FCGR for early maturing cultivars gradually declined 6 wk after transplanting and varied among late maturing cultivars. `Carver II' showed increases in FCGR up to 11 wk after transplanting then rapidly declined while `Rojo-Blanco' and TU-1892 began to decline 8 and 6 wk after transplanting, respectively. RCGR showed rapid increases (100 g.m /area/week) and (150 g/m /area/week) for early and late maturing cultivars beginning 6 wk after transplanting and this increase continued until the 12th and 8 th wk after transplanting for early and late maturing cultivars, respectively. Cultivars from both maturity groups began to produce surplus assimilates (Alpha a) 6 wk after transplanting. which coincided with the rapid increases in RCGR at the same time. Thus indicating that storage root enlargement begins after the plant had accumulated a surplus of assimilates.

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