The growth of the young coconut palm (Cocos nucifera L.). I. The role of the seed and of photosynthesis in seedling growth up to 17 months of age

1968 ◽  
Vol 19 (5) ◽  
pp. 781 ◽  
Author(s):  
MA Foale
Keyword(s):  
Cocos Nucifera ◽  
Gradual Change ◽  
Leaf Production ◽  
Relative Growth ◽  
Cultural Methods ◽  
Relative Contribution ◽  
Exact Date ◽  
Net Assimilation ◽  
Cocos Nucifera L

The growth of coconut seedlings and the changes occurring within the seed were studied over a period of 17 months from the germination of the coconuts. Removal of the husk prior to germination made possible an estimate of the endosperm content of each seed and also permitted the exact date of germination to be observed. Seedlings were grown with a non-limiting supply of water and nutrients; 63 seedlings were harvested on each of 10 occasions to enable a growth analysis to be made. A high initial relative growth rate, arising through contributions by the endosperm, fell at 4 months to a level which remained roughly constant to 17 months. By 4 months the haustorium had reached its full size, but thereafter the relative contribution from the endosperm via the haustorium was much diminished. Between 4 and 15 months a gradual change over to full dependence on photosynthesis took place. By 17 months less than 10% of the endosperm remained in the nut. The rate of leaf production was constant with time, but the leaf area increased almost exponentially. There was some indication of a positive relationship between net assimilation rate and solar radiation. Some conclusions are drawn concerning cultural methods with young coconuts.

The growth of the young coconut palm (Cocos nucifera L). II. The influence of nut size on seedling growth in three cultivars

1968 ◽  
Vol 19 (6) ◽  
pp. 927 ◽  
Author(s):  
MA Foale
Keyword(s):  
Seedling Growth ◽  
Dry Matter ◽  
Growth Analysis ◽  
Cocos Nucifera ◽  
Plant Size ◽  
Seedling Vigour ◽  
Sustained Effect ◽  
Net Assimilation ◽  
Cocos Nucifera L ◽  
Growth Of Seedlings

The growth of three coconut cultivars of the tall type from germination up to 17 months of age was compared by growth analysis. These cultivars differ considerably in mean nut size. Within each cultivar a comparison was also made between the growth of seedlings from small, medium, and large nuts. There were considerable differences between cultivars in seedling growth up to 2 months but these differences did not persist. Similarly differences due to nut size within cultivars were recorded at early harvests but had disappeared by 6 months. Thus neither genotype nor nut size had any sustained effect on the plant size. Consumption of endosperm depended on seed size: evidently a lower, compensating net assimilation rate occurred in plants with large nuts to give a similar total supply of assimilate. This suggests that the potential supply of assimilate was not limiting the growth rate. Large nuts transfer dry matter from the endosperm more rapidly than do smaller nuts; hence under unfavourable conditions for photosynthesis, larger nuts may produce larger seedlings. It is suggested that any seedling selection should be done in a favourable nursery environment so that emphasis is placed on differences in seedling vigour due to genetic variation.

scholarly journals WATER RELATION, GAS EXCHANGE AND DRY MATTER PRODUCTION OF COCONUT (COCOS NUCIFERA, L.) UNDER UNIRRIGATED AND IRRIGATED CONDITIONS

CORD ◽  
1997 ◽  
Vol 13 (02) ◽  
pp. 34
Author(s):  
K.V. Kasturi Bai ◽  
V. Rajagopal ◽  
D. Balasimha ◽  
P. Gopalasudaram
Keyword(s):  
Gas Exchange ◽  
Dry Matter ◽  
Cocos Nucifera ◽  
Irrigation Treatment ◽  
Water Relation ◽  
Beneficial Effects ◽  
Matter Production ◽  
Net Assimilation ◽  
Cocos Nucifera L ◽  
Better Than

The response of local West Coast Tall (WCT) and the two hybrids viz., WCT x Chowghat Orange dwarf (COD) and COD x WCT to moisture availability in terms of water relation, gas exchange and dry matter (DM) production was studied. Discernible differences were noticed between the irrigation treatment (viz., irrigated vs unirrigated) with lower stomatal conductance and transpiration rate in the palms with out irrigation. Irrespective of the cultivar of hybrid leaf water potential was also significantly higher in irrigated palms. Net assimilation rate was lower under uniriigated condition. However genotypic or treatment differences were not significant. Annual DM production also vaned markedly between the irrigation treatments. Treatment differences were significant on the reproductive (RDM) rather then vegetative DM (VDM) production. Under the irrigation treatment the hybrids performed better than the local tall However the percentage reduction in the DM production was relatively less in the local WCT cultivar under unirrigated as compared with irrigated condition. The studies clearly highlighted the beneficial effects of irrigation on DM production and yield in coconut and the adaptability of the local WCT variety under limited water supply than the two hybrids.

scholarly journals INFLUENCE OF DRIP IRRIGATION ON GROWTH AND YIELD OF COD X WCT COCONUT (COCOS NUCIFERA L.) HYBRID

CORD ◽  
2004 ◽  
Vol 20 (01) ◽  
pp. 34
Author(s):  
R. Dhanapal ◽  
H. P. Maheswarappa ◽  
P. Subramanian ◽  
Ajay Kumar Upadhyay
Keyword(s):  
Drip Irrigation ◽  
Cocos Nucifera ◽  
Female Flower ◽  
Nutrient Status ◽  
Growth And Yield ◽  
Leaf Production ◽  
Flower Production ◽  
Basin Irrigation ◽  
Cocos Nucifera L ◽  
Plantation Crops

A field experiment on drip irrigation for Chowghat Orange Dwarf X West Coast Tall (COD X WCT) coconut hybrid was conducted in laterite soil at Central Plantation Crops Research Institute, Kasaragod (Kerala, India) to study the drip irrigation requirement and its influence on growth and yield.  The treatments included were three levels of drip irrigation (at 33, 66 and 100% E0 daily), basin irrigation  (100%  E0)  and  rainfed  control.     The  experimental  results  revealed  that  annual  leaf production and leaf nutrient status of coconut palm was significantly higher in the irrigated treatments compared to the rainfed control. The female flower production and nut yield with 66 per cent of Eo was on par with 100 per cent of Eo through drip and 100 per cent of Eo through basin irrigation and significantly  superior  compared  to drip irrigation  at 33 per cent of E0  and rainfed  control.   Drip irrigation equal to 66 per cent of open pan evaporation (Eo) proved to be the economically efficient method of irrigation with water saving of 34 per cent compared to 100 per cent of Eo through basin and drip method.

Gibberellic acid induced growth acceleration in Populus hybrids

1984 ◽  
Vol 14 (6) ◽  
pp. 850-854 ◽  
Author(s):  
S. B. Rood ◽  
G. Daicos ◽  
T. J. Blake
Keyword(s):  
Gibberellic Acid ◽  
Leaf Area ◽  
Foliar Spray ◽  
Dry Weight ◽  
Height Growth ◽  
Total Leaf Area ◽  
Leaf Production ◽  
Relative Growth ◽  
Shoot Dry Weight ◽  
Net Assimilation

Weekly applications of 0.4 mg gibberellic acid (GA) in 8 μL 95% ethanol micropipetted onto shoots of rooted cuttings increased Populuseuramericana (Dode) Guinier height growth by 54% and shoot dry weight by 25% after 21 days. Total leaf area increased by 21% as a result of more rapid leaf production and slightly larger leaf sizes. Root growth was unaffected by GA treatment. The observed GA-induced acceleration resulted from an increase in relative growth rate while mean net assimilation rate was unaffected. Owing to a substantial increase in the number and size of leaves, the leaf area ratio, representing the ratio of photosynthesizing to respiring material, increased. While direct micropipette application of GA promoted height growth and primary shoot dry weight accumulation, GA application through either foliar spray or soil drench also promoted the growth of secondary shoots. Application of GA to shoots was more effective in promoting shoot growth than application through the roots. Direct GA application also promoted the growth of P. alba L. × P. grandidentata Michx. and P. × canescens (Ait.) Smith × P. alba × P. grandidentata. Thus, GA can be used for hastening early growth of these trees under winter greenhouse conditions.

scholarly journals INFLUENCE OF DRIP IRRIGATION ON GROWTH AND YIELD OF COD X WCT COCONUT (COCOS NUCIFERA L.) HYBRID

CORD ◽  
2003 ◽  
Vol 19 (02) ◽  
pp. 34
Author(s):  
R. Dhanapal ◽  
H. P. Maheswarappa ◽  
P. Subramanian ◽  
Ajay Kumar Upadhyay
Keyword(s):  
Drip Irrigation ◽  
Cocos Nucifera ◽  
Female Flower ◽  
Nutrient Status ◽  
Growth And Yield ◽  
Leaf Production ◽  
Flower Production ◽  
Basin Irrigation ◽  
Cocos Nucifera L ◽  
Plantation Crops

A field experiment on drip irrigation for Chowghat Orange Dwarf X West Coast Tall (COD X WCT) coconut hybrid was conducted in laterite soil at Central Plantation Crops Research Institute, Kasaragod (Kerala, India) to study the drip irrigation requirement and its influence on growth and yield.  The treatments included were three levels of drip irrigation (at 33, 66 and 100% E0 daily), basin irrigation (100% E0) and rainfed control.  The experimental results revealed that annual leaf production and leaf nutrient status of coconut palm was significantly higher in the irrigated treatments compared to the rainfed control. The female flower production and nut yield with 66 per cent of Eo was on par with 100 per cent of Eo through drip and 100 per cent of Eo through basin irrigation and significantly superior compared to drip irrigation at 33 per cent of E0 and rainfed control.  Drip irrigation equal to 66 per cent of open pan evaporation (Eo) proved to be the economically efficient method of irrigation with water saving of 34 per cent compared to 100 per cent of Eo through basin and drip method. 

Phenotypic Plasticity of Chinese Sprangletop (Leptochloa chinensis) in Competition with Seeded Rice

2011 ◽  
Vol 25 (4) ◽  
pp. 652-658 ◽  
Author(s):  
Bhagirath S. Chauhan ◽  
David E. Johnson
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Production Rate ◽  
Tiller Number ◽  
Shoot Biomass ◽  
Assimilation Rate ◽  
Leaf Production ◽  
Relative Growth ◽  
Rice Plants ◽  
Net Assimilation

Chinese sprangletop, a C4species, is one of the most important grass weeds of seeded rice in Asia. Chinese sprangletop biology was studied by growing it alone and in competition with 4 and 12 rice plants. Rice competition did not affect the height of Chinese sprangletop, and the weed grew taller than rice, regardless of the competition. Compared with Chinese sprangletop grown alone, competition from rice reduced Chinese sprangletop leaf number, leaf production rate, tiller number, tiller production rate, leaf area, shoot biomass, relative growth rate, and net assimilation rate. Leaf area and shoot biomass of Chinese sprangletop when grown in competition with 12 rice plants was only 16% and 13%, respectively, of the leaf area and biomass of the weed grown alone.

Growth of Dracaena marginata and Spathiphyllum ‘Petite’ in Sphagnum Peat- and Coconut Coir Dust-based Growing Media

1999 ◽  
Vol 17 (1) ◽  
pp. 49-52 ◽  
Author(s):  
Robert H. Stamps ◽  
Michael R. Evans
Keyword(s):  
Growth Parameters ◽  
Cocos Nucifera ◽  
Greenhouse Production ◽  
Growing Media ◽  
Sphagnum Peat ◽  
Affected Plant ◽  
Coir Dust ◽  
Media Component ◽  
The Media ◽  
Cocos Nucifera L

Abstract A comparison was made of Canadian sphagnum peat (SP) and Philippine coconut (Cocos nucifera L.) coir dust (CD) as growing media components for greenhouse production of Dracaena marginata Bak. and Spathiphyllum Schott ‘Petite’. Three soilless foliage plant growing mixes (Cornell, Hybrid, University of Florida #2 [UF-2]) were prepared using either SP or CD and pine bark (PB), vermiculite (V), and/or perlite (P) in the following ratios (% by vol): Cornell = 50 CD or SP:25 V:25 P, Hybrid = 40 CD or SP:30 V:30 PB, UF-2 = 50 CD or SP: 50 PB. Dracaena root growth was not affected by treatments but there were significant mix × media component interactions that affected plant top growth parameters. In general, the growth and quality of D. marginata were reduced by using CD in Cornell, had no effect in Hybrid, and increased in UF-2. S. ‘Petite’ grew equally well in all growing mixes regardless of whether CD or SP was used; however, plants grew more in Cornell and Hybrid than in UF-2. S. ‘Petite’ roots, which were infested with Cylindrocladium spathiphylli, had higher grades when grown in CD than when the media contained SP.

A Developmental Perspective on the Genetic Basis of Alcohol Use Disorder

2018 ◽  
Author(s):  
Elisa M. Trucco ◽  
Gabriel L. Schlomer ◽  
Brian M. Hicks
Keyword(s):  
Alcohol Use ◽  
Alcohol Use Disorder ◽  
Developmental Perspective ◽  
Relative Contribution ◽  
Intermediate Phenotypes ◽  
Problematic Alcohol ◽  
Age Related ◽  
Genetic And Environmental Factors ◽  
Problematic Alcohol Use

Approximately 48–66% of the variation in alcohol use disorders is heritable. This chapter provides an overview of the genetic influences that contribute to alcohol use disorder within a developmental perspective. Namely, risk for problematic alcohol use is framed as a function of age-related changes in the relative contribution of genetic and environmental factors and an end state of developmental processes. This chapter discusses the role of development in the association between genes and the environment on risk for alcohol use disorder. Designs used to identify genetic factors relevant to problematic alcohol use are discussed. Studies examining developmental pathways to alcohol use disorder with a focus on endophenotypes and intermediate phenotypes are reviewed. Finally, areas for further investigation are offered.

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