Growth Of Taro Research Articles

Effect of different levels of fertilizer and plant spacing on growth of taro (Colocasia esculenta L.) genotype under Marathwada conditions

Effect of different levels of fertilizer and plant spacing on growth of taro (Colocasia esculenta L.) genotype under Marathwada conditions

Hydrologic modelling of niche construction at the Waitetoke Cultivation Complex, Ahuahu, Aotearoa New Zealand

The early Māori settlers of Ahuahu, a small island off the Coromandel Peninsula of Aotearoa New Zealand, engineered the environment to create a raised-bed irrigation system to grow taro (Colocasia esculenta). Three-dimensional computational fluid dynamic (CFD) modelling of water flow provides insights into how the irrigation system functioned. Excavation and coring data and a digital elevation model combine to simulate the hydrology of the raised-bed irrigation system at Waitetoke on Ahuahu. This modelling demonstrates that for operation, the system required a series of channels and weirs to divert water from a nearby spring. The slow-moving water delivered nutrients to the cultivation area and also promoted the growth of nitrogen fixing algae. Exogenous nutrients including wood ash and calcium carbonate along with fire modified rocks derived from nearby household hearths added to the cultivation matrix created ideal conditions for taro growth. Over the span of over two hundred years, Māori engaged in various forms of niche construction to enhance taro production by altering feedback relationships between the geomorphology of the area, a natural spring, the constructed channels and weirs, water, cultivars, algae, and soil nutrients.

Transcriptome-based identification and validation of reference genes for corm growth stages, different tissues, and drought stress in Taro (Colocasia esculenta)

Taro is a widely utilized starch resource plant. It is essential to quantify the expression levels of functional genes associated with taro growth using real-time quantitative polymerase chain reaction (RT-qPCR). However, to obtain reliable RT-qPCR results, appropriate reference genes (RGs) are required for data normalization. In this study, we screened seven novel candidate RGs using transcriptome datasets from taro, encompassing data from growth corms and various tissues. The expression stability of these seven new RGs, along with the commonly used RGs Actin, EF1-α, and β-tubulin, was assessed using Delta Ct, BestKeeper, geNorm, and NormFinder algorithms. Furthermore, we conducted a comprehensive analysis using the RefFinder program and validated the results using the target gene, CeAGPL1. The findings revealed that ACY-1 and PIA2 were the optimal multiple RGs for normalization during corm growth, while COX10 and Armc8 were suitable for samples including various types of tissues. Furthermore, we found three RGs, Armc8, COX10 and CCX4L, were the optimal RGs for drought stress. This study assessed the suitability of RGs in taro for the first time. The identified RGs provide valuable resources for studying corm growth, diverse tissues, and drought stress. This study contributes to the advancement of our understanding of the underlying mechanisms that govern the growth of taro.

Drought Stress Inhibits Starch Accumulation in Taro (Colocasia esculenta L. Schott).

Colocasia esculenta L. Schott is a main traditional root crop in China, serving as an important vegetable and staple food. Drought stress plays vital role on the growth and development of taro corm. Two different varieties of taro in Jiangsu were selected: Xiangsha taro and Longxiang taro. The accumulation characteristics, morphological structure, and physicochemical properties of taro corm starch were studied by microscopic observation, particle size analysis, and X-ray diffractometer (XRD) analysis. Transcriptome analyses were used to identify the related genes of taro corm under drought stress. During the growth of taro, the number of amyloplasts showed an obvious increasing trend and shifted from being dispersed throughout the cells to being gathered on one side of the cells, and morphological observations showed that smaller granular distribution gradually changed to a larger lumpy distribution. The particle size of Longxiang taro is smaller than that of Xiangsha taro. Under drought stress conditions, the occurrence of starch grains and corm size were inhibited in Xiangsha taro. Transcriptome sequencing of drought-stressed taro corms showed that the enzymes related to starch synthesis were differentially expressed. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of drought-stressed taro corms showed that drought affected hormone signal transduction, material metabolism, drought stress tolerance, plant growth and development, and stress resistance, which triggered the plant drought adaptive response. Drought stress inhibits starch accumulation in taro.

Effects of Watering Regimes and Planting Density on Taro (Colocasia esculenta) Growth, Yield, and Yield Components in Embu, Kenya

Taro (Colocasia esculenta (L.) Schott) is one of the most underutilized crops in sub-Saharan Africa and an important staple food in the tropics. Understanding its growth response under selected watering regimes and planting densities underpins this research. A study was conducted at the Kenya Agricultural and Livestock Research Organization (KALRO), Embu Research Centre, during the long rains (LR) in 2021 and the short rains (SR) in 2021–2022. A factorial experiment with a split-plot layout arranged in a completely randomized block design was used. The main factor was the irrigation levels, while the subfactor was the planting density, with three replications. The three irrigation levels were at 100%, 60%, and 30% based on the field capacity (FC). The planting densities used were 0.5 m × 0.5 m (40,000 plants ha−1), 1 m × 0.5 m (20,000 plants ha−1), and 1 m × 1 m (10,000 plants ha−1), representative of high, medium, and low planting densities, respectively. Time and season ( P < 0.05 ) significantly influenced taro growth components (plant height, leaf area, leaf area index, and vegetative growth index) and yield components (corm length, corm diameter, corm mass, yield, and total biomass). Planting density influenced the leaf area and the leaf area index ( P < 0.05 ). The watering regime did not affect taro growth or yield components. Corm mass (0.59 kg), total biomass (49.8 t/ha), and yield (13.38 t/ha) were all the highest in the 30% FC. The 1 m × 0.5 m spacing produced the highest corm mass (0.62 kg). The high planting density (0.5 m × 0.5 m) resulted in the highest total biomass (70.2 t/ha), yield (20.84 t/ha), and harvest index (30.44%). As a result, the 0.5 m × 0.5 m planting density and 30% FC watering regime are recommended to farmers in the area for increased yields and food security.

Microalgae as a potential conditioner for continuous cropping obstacles for taro (Colocasia esculenta L. Schott) production

Continuous cropping of Fenghua taro leads to poor quality. In this research, two pollution tolerant algae, Spirulina platensis and Chlorella vulgaris, were selected as conditioners for continuous cropping obstacles of taro production. The composition, abundance, and biodiversity of the bacteria and fungi communities in soil rhizosphere of continuous cropping were compared to non-continuous cropping, and studied in-depth. These results showed that the growth of taro during continuous cropping, when irrigated with Chlorella vulgaris and Spirulina platensis, was significantly better than the control group without algal cell irrigation. Accordingly, the plant height, leaf length, leaf area, moisture, carbohydrate, and protein in continuous cropping were 128 cm, 69 cm, 56 cm, 72 g/100 g, 10.8 g/100 g and 2.4 g/100 g, respectively, when watered with Chlorella vulgaris. Furthermore, compared with continuous cropping, the abundance of plant pathogens in the taro rhizosphere, fertilized with Spirulina platensis, were significantly reduced, while the corresponding abundance of soil beneficial bacteria was significantly increased. Specifically, the abundance of beneficial bacteria Ceratobasidium and Pulveroboletus increased, and the pathogens such as Curvularia, Erysiphe, and Clonostachys decreased, during continuous cropping when irrigated with Spirulina platensis. Live microalgae, after wastewater treatment, could be used as potential conditioners to avoid obstacles during continuous cropping of taro production.

Potential of Three Taro (Colocasia esculenta L.) Cultivars as Animal Feed

The growth and yield of taro (Colocasia esculenta L.) plants are influenced by the planting material. The use of planting material derived from corms is expected to improve the quality and quantity of taro growth and yield. This research aimed to find the best type of planting material and cultivars for taro growth and the potential of taro plants as animal feed. The experiment was carried out in Jember, East Java ( elevation ±89 m asl). The experiment used the randomized completed block design method with two treatment factors, the type of planting material (B) as the first factor (B1: taro corms, B2: taro tiller, B3: taro stolon) and the use of taro cultivars (V) as the second factor (V1: green taro, V2: ketan taro, V3: Sukabumi taro). The treatment was repeated four times. The results showed that there was an interaction between the use of taro planting material and taro cultivar that could influence the tuber weight per plant. The types of planting material had a significant effect on the number of tillers, leaf area, corm weight and diameter, and the planting of several taro cultivars significantly affected all observed variables. The treatment that gave the best results was planting material from taro tuber (B1) and Sukabumi cultivar (V3) with a tuber weight yield of 362.58 g (±14.5 tons/ha). Meanwhile, the Sukabumi cultivar (V3) had the best potential as animal feed. Overall, the stems and leaves of taro had a protein content of 1.19–2.02%, while the corms had 2.82–4.09%.

Increase in vitamin levels to improve shoot growth of diploid, triploid and tetraploid taro cultured in liquid medium

Taro (Colocasia esculenta (L.) Schott) is one of important food crop in many countries including Indonesia, which has big diversity of taro germplasm. Tissue culture is an in vitro technique to mass-propagated propagules. Modification of the medium compositions is required to obtain the best growth of plantlets. This research was aimed to accelerate growth of taro shoot cultures by increasing of the vitamin levels added on MS liquid medium using three different ploidy levels of taro. Experiments were designed by increasing three kind of vitamin B i.e. thiamine, pyridoxine and nicotinic acid to 100-fold of the normal concentrations. Shoots were cultured for 4 weeks. Growth was determined by recording shoot numbers, petiole length, leaf and root numbers of culture. The results showed that increase in vitamin B levels affected growth of taro culture. Increase in nicotinic acid gave the best petiole length for Bentul diploid (5.39 cm), increase in pyridoxine concentration enhanced root numbers (6.7 roots). For Satoimo triploid, increase in thiamine combined with nicotinic acid gave the best for root numbers (8.7 roots). For Bentul tetraploid, increase in pyridoxine accelerated shoot numbers (1.3 shoots). Growth of Satoimo triploid was the best compared to both Bentul diploid and tetraploid.

Changes in Chemical Properties of Soil under Poplar based Agroforestry System and Open Farming System

The present investigation was carried out at Agroforestry Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India, to study the chemical property of soil before and after the growth of taro as sole crop and under poplar based agroforestry system. After planting of taro, soil pH was observed maximum for germplasm PA-73 (7.23) and PA-16 (7.15), EC was observed maximum for germplasm PA-56 (0.40 dSm -1 ) and PA-60 (0.36 dSm -1 ) and soil organic carbon (OC) was observed maximum for germplasm PA-49 (1.17%) and PA-73 (1.06%) under poplar based agroforestry system and open system respectively, whereas after harvesting of taro, the maximum soil pH was observed with germplasm PA-16 for both the condition, which was 7.20 and 7.14, maximum soil EC was observed with germplasm PA-56 (0.39 dSm -1 ) and germplasm PA-60 (0.35 dSm -1 ) and maximum soil OC was observed under poplar based agroforestry system as compared to open system respectively. Results of the present study revealed that the chemical property of soil varied significantly in different taro germplasm under poplar based agroforestry system as compared to open farming system.

Influences of water management combined with organic mulching on taro plant growth and corm nutrition

ABSTRACT Taro (Colocasia esculenta L. Schott) is an important food staple in developing countries in Africa, West Indies, the Pacific region, and Southeast Asia. Because taro can be grown in almost all tropical regions of the world, it will play a crucial role in food security. The use of organic mulches, which contribute to soil water management, weed control, and fertilization simultaneously, shows promise as an eco-friendly approach in agronomy. In the present study, a field experiment including two cropping seasons (I and II) was conducted to evaluate the effects of water regimes with organic mulching on the taro growth and corm nutritive values. In results, compared with that under the upland regime, taro cultivation under the flooding regime had a higher level of soil fertility and better weed control. The flooding regime promoted more the taro plant growth and further enhanced the yields of the harvested corms; also, sugarcane bagasse and rice husk would be the superior mulch to obtain better corm attributes. By contrast, cultivation under the upland regime enhanced the nutritive values of taro corm more than did that under the flooding regime. Regardless of the upland or flooded regime, mulching treatments with rice husk could enrich taro corm nutrition more than could those with sugarcane bagasse and peanut hull. Also, the effects of water regime and mulching on taro plant growth and corm attributes would be varied with the rainfalls during the period of vegetative growth.

EFFECT OF NITROGEN FERTILIZER RATES AND WEED CONTROL TREATMENTS ON WEEDS GROWTH AND PRODUCTIVITY, QUALITY AND ECONOMIC FEASIBILITY OF TARO CROP

Two field experiments for taro vegetable crop were carried out in ElKanater El-Khiria, Horticulture Research Station, Kalubia Governorate, Egypt, in a split plot design during the two successive 2015 and 2016 seasons. This study aimed to investigate the effects of two nitrogen fertilizer rates at 90 or 120 kg/ fed. in main plots and nine weed control treatments in sub plots i.e. Harness at one liter/ fed., Sencor at 300 g/ fed. and Stomp extra at 1.7 liter/ fed. each individual and/ or plus Roundup at one liter/ fed., Roundup individual, hand hoeing twice after 25 and 40 days from sowing and untreated check (control) on weeds growth and vegetative growth, yield, quality and economic feasibility of taro. The main findings of this research revealed that nitrogen fertilizer rate at 90 kg/ fed. gave the highest decrease in dry weight of weed categories i.e. , broadleaf weeds, grassy weeds and total weeds in both seasons and increased diameter and weight of taro corm in the second season. Whereas, taro plant height, taro number of leaves/ plant and uptake of nitrogen by weeds were increased by application of nitrogen rate at 120 than 90 kg/ fed. during the two seasons without any significant differences in the yield of taro, its components, chlorophyll content and chemical analysis characterized. The use of Stomp extra at 1.7 liter/ fed. applied as post-sowing plus Roundup at one liter/ fed. after 25 days from sowing applied as taro pre-emergence above soil surface exhibited significantly decreased in dry weight of total weeds by 96.9 and 95.1 % in first and second seasons, respectively. Application of Seconr at 300g /fed. plus Roundup at rate of one liter/ fed. reduced the previous total weeds by 93.3 and 94.5% and increased taro yield (43.6 and 43.5%) in the first and second seasons, respectively. Thus, these herbicides can broaden weed control weed spectrum with long weed control season, which minimize taro yield by weed competition, consequently eliminated N uptake from soil and improved protein and starch accumulation in favor taro crop yield. Also, it can be advised as alternative hand hoeing to weed control in this crop with economic feasibility and delectable herbicides residues and under permissible levels which accompanied with high quality for taro growth characteristics i.e. plant height, number of leaves/ plant and chlorophyll reading in leaves, corm length, corm diameter, corm weight, corm fresh yield, dry matter % and chemical of taro corms (protein percentage, starch percentage and total nitrogen of corm yield).

Effects of solar UV-B radiation exclusion on physiology, growth and yields of taro (Colocasia esculenta (L.)) at different altitudes in tropical environments of Southern Ethiopia

Plants are sessile by nature, they have to be able to cope with exposure to many biotic and abiotic stress factors, including solar UV-B radiation. The degree of stresses varies with geographic locations. The impact of solar UV radiation on growth, physiology and yield of taro (Colocasia esculenta (L.)) at different altitudes under tropical environments was evaluated in Southern Ethiopia at 1500 m, 1800 m and 2200 m a.s.l. The experiment was conducted under open field conditions, and was compared to the yield of taro under UV-B blocking plastic film at every location. Four taro cultivars (‘Black’, ‘Boloso-1’, ‘Purple’ and ‘White’) were used as planting materials. Each treatment was planted using RCB design with three replications. The result indicates that leaf number, shoot number, leaf area and leaf area index under UV-B exclusion were found to be higher at higher elevation than either lower or middle elevation for ‘Boloso-1’ and ‘Black’ cultivars. Exclusion of UV-B spectrum from solar radiation improved the number of leaves and the leaf area index, for two cultivars: ‘Black’ and ‘Boloso-1’. Blocking UV-B radiation also significantly enhanced stomata conductance, photosynthesis rate stomata opening area, stomata number and dry matter in ‘Boloso-1’, compared to other cultivars. However, physiologically ‘Purple’ cultivar did not respond to solar UV-B irradiation. Among all the cultivars, ‘Boloso-1’ was found to be a good candidate for maximum corm size, marketable and maximum total yield production in all test locations irrespective of solar UV-B irradiation. In conclusion, vegetative growth of taro cultivars responded better to altitudinal variation than variability of UV-B irradiation. Whereas, physiological parameters like stomata number, stomata opening area, stomata conductance and photosynthesis of different taro cultivars responded stronger to the level of UV-B irradiation than the altitude.

EFFECT OF NITROGEN FERTILIZER RATES AND WEED CONTROL TREATMENTS ON WEEDS GROWTH AND PRODUCTIVITY, QUALITY, AND ECONOMIC FEASIBILITY OF TARO CROP

Two field experiments for taro vegetable crop were carried out in ElKanater El-Khiria, Horticulture Research Station, Kalubia Governorate, Egypt, in a split plot design during the two successive 2015 and 2016 seasons. This study aimed to investigate the effects of two nitrogen fertilizer rates at 90 or 120 kg/ fed. in main plots and nine weed control treatments in sub plots i.e. Harness at one liter/ fed., Sencor at 300 g/ fed. and Stomp extra at 1.7 liter/ fed. each individual and/ or plus Roundup at one liter/ fed., Roundup individual, hand hoeing twice after 25 and 40 days from sowing and untreated check (control) on weeds growth and vegetative growth, yield, quality and economic feasibility of taro. The main findings of this research revealed that nitrogen fertilizer rate at 90 kg/ fed. gave the highest decrease in dry weight of weed categories i.e. , broadleaf weeds, grassy weeds and total weeds in both seasons and increased diameter and weight of taro corm in the second season. Whereas, taro plant height, taro number of leaves/ plant and uptake of nitrogen by weeds were increased by application of nitrogen rate at 120 than 90 kg/ fed. during the two seasons without any significant differences in the yield of taro, its components, chlorophyll content and chemical analysis characterized. The use of Stomp extra at 1.7 liter/ fed. applied as post-sowing plus Roundup at one liter/ fed. after 25 days from sowing applied as taro pre-emergence above soil surface exhibited significantly decreased in dry weight of total weeds by 96.9 and 95.1 % in first and second seasons, respectively. Application of Seconr at 300g /fed. plus Roundup at rate of one liter/ fed. reduced the previous total weeds by 93.3 and 94.5% and increased taro yield (43.6 and 43.5%) in the first and second seasons, respectively. Thus, these herbicides can broaden weed control weed spectrum with long weed control season, which minimize taro yield by weed competition, consequently eliminated N uptake from soil and improved protein and starch accumulation in favor taro crop yield. Also, it can be advised as alternative hand hoeing to weed control in this crop with economic feasibility and delectable herbicides residues and under permissible levels which accompanied with high quality for taro growth characteristics i.e. plant height, number of leaves/ plant and chlorophyll reading in leaves, corm length, corm diameter, corm weight, corm fresh yield, dry matter % and chemical of taro corms (protein percentage, starch percentage and total nitrogen of corm yield).

Pertumbuhan Vegetatif Talas Satoimo dan Kultivar Lokal pada Dosis Pupuk Nitrogen yang Berbeda

Taro (Colocasia esculenta L. Schott) is a plant that has an excellent economic and healthy value, as well as a great potential development of Bengkulu coastal area. That is because taro has wide adaptability, and can be consumed both as a staple food and healthy food alternative. This research was conducted to study the vegetative growth of two cultivars of taro given four different doses of nitrogen. This study applied a Randomized Complete Block Design (RCBD) with two factors. The first factor was the cultivar of taro consisted of two levels, namely Taro Satoimo (T1) and the Taro Local (T2). The second factor was the doses of nitrogen fertilizer which consisted of four levels namely: N0 = 0 kg / ha (control), N1 = 50 kg / ha (2.6 g, N2 = 100 kg / ha, and N3 = 150 kg / ha. Thus, obtained eight treatment combinations. Each treatment was repeated three times to get 24 plots. The results showed that based on increased vegetative growth, the cultivar Satoimo has a faster response than local cultivar. Satoimo has demonstrated another advantage because it produced some leaves and number new shoot. The best dose of nitrogen fertilizer on the vegetative growth of taro in the coastal area of Bengkulu is 150 kg/ha.

Effect of polyethylene mulching on the spatial variability of soil physical properties and growth parameters of taro (Colocasia esculantum)

The objective of this study was to investigate the spatial variability of soil physical properties and growth of taro (Colocasia esculantum) in an unfertilized 42 m ridge covered with black plastic mulch. The study was conducted at the National Agriculture Research Centre Tsukuba (Japan). The experimental field was made of 3 adjacent ridges of 42 m long and 0.90 m width each. Uniform taro corms were planted in the middle of each ridge at 0.30 m spacing. At the end of growing season, soil samples were taken for measurements of air content (¦a), bulk density (rb), gravimetric (qg) and volumetric water contents (qv), total pore space (TPS), pore tortuosity (t), gas diffusion coefficient (DSDO) and water-filled pore space (WFPS). Taro plants were harvested, separated into leaves (LFW), petioles (PFW), corms (CFW), roots (RFW) and tubers (TFW). All autocorrelation functions (r(h)) for soil properties and taro growth dropped sharply after one lag. Except forqg, (r(h) for qa, rb, Ds/Do and WFPS dropped below zero at about 16 lags, which revealed that these soil properties could be sampled at 4.8 m for independent observations. For taro growth parameters, only PFW, TFW and RFW could be sampled together at 14 lags or 4.2 m for uncorrelated observations. Except for RFW, all taro growth parameters significantly correlated among themselves and with qg, ¦a, rb, Ds/Do, WFPS and t with correlation coefficients ranging from 0.16 to 0.99. Plastic mulch improved soil properties which in turn improved the relationship between these properties and taro growth parameters. Key words: Soil physical properties, taro growth parameters, plastic mulch, volcanic ash soil.

Growth and development of wetland-grown taro under different plant populations and seedbed types in Uganda

Taro [Colocasia esculenta (L.) Schott] is a member of the Araceace family that is a staple food for many people in developing countries in Africa, Asia and the Pacific Islands. It is widely grown in Uganda but the extent of its production and consumption is not known, partly because it has been ignored as legitimate crop for research anddevelopment (R&D), and it is managed outside the conventional agricultural production, marketing and economic channels. Therefore, there is limited information on many aspects of taro, including agronomic practices. In order obtain data that can support improved and sustainable taro production, a field trial was conducted over twocropping seasons at Kabanyolo in central Uganda, to determine the effect of three taro plant populations (10,000, 17,760 and 40,000 pph) and two seedbed types (flat and ridged seedbed) on growth and yield of taro. The treatments were arranged in a split – split – plots design, with three replications. Seedbed type was in the main plot and plant populations in the sub-plots. These were further split to accommodate five sampling dates for plant growth. Each experimental subplot measured 6 m x 6 m and contained 36, 64 and 144 experimental plants, respectively. During a 5-month growth period, leaf area index (LAI) and corm yield were significantly (P < 0.05) higher in closely spaced plants (high plant population). Seedbed type had no (P>0.05) effect on taro growth and yield. However, using high plant population may not be recommended because of the enormous amount ofplanting material that would be needed. From this study, a moderately wide spacing of 0.75 m x 0.75 m which produced an acceptable yield of 5.5 – 6.8 t ha-1 would be recommended.

Influence of Different Cultural Condition on the Plant Growth of Taro

Influence of Different Cultural Condition on the Plant Growth of Taro

Influence of Different Cultural Condition on the Plant Growth of Taro 2. Effect of soil pH on the phase of fission of tuber of the Taro

Influence of Different Cultural Condition on the Plant Growth of Taro 2. Effect of soil pH on the phase of fission of tuber of the Taro

Evaluation of performance of rice (&lt;i&gt;Oryza sativa&lt;/i&gt;) and taro (&lt;i&gt;Colocasia esculenta&lt;/i&gt;) in a mixed cropping system

Taro (Colocasia esculenta (L) Schott var. esculenta) is widely distributed and cultivated in the wet tropics of the world. In Ghana, its cultivation is limited to river basins or banks in large cities. However, a few farmers grow it on a large scale and rank it as their main source of income. A major problem identified in its production is the flooded culture that makes its cultivation intensive and expensive, and the seasonality in marketing the crop. This necessitated the introduction of rice into the cropping system to increase productivity per unit area and increase income of farmers. To facilitate technology transfer and adoption of this technique, an integrated approach was used. The participatory research–farmer–extension approach is described. Rice growth measure, as height, tiller and effective tiller counts were not significantly influenced in the system. Rice growth was better on the rotation and intercrop plots. Although rice height, tillers and effective tillers were higher for the intercrop system, yields under this system were lower because of the negative correlations that exist between rice height, tillers, and grain yield. Taro growth measured as petiole length and leaf number increased with time on all systems; the rate of increase was higher for sole crop than the intercrop system. Rice reduced taro petiole length and increased leaf number in the intercrop. Tuber sizes were the same for all treatments, but final taro yields were reduced. The average performance of the rice crop in the intercrop was the same (0.85), whilst that of taro varied within the study period, giving values of 1.35 – 1.5. The taro crop (1.65) was found to be more competitive or aggressive than rice (0.6) in the intercrop system. The intercrop had LER values of 1.1 and 1.2, signifying a better option in terms of land resource use. Ghana Journal of Agricultural Science Vol. 37 2004: 49-57

Site and Planting Date Effects on Taro Growth

Taro [Colocasia esculenta (L.) Schott cv. Bun‐long] is a tropical root crop with the potential to be grown commercially on former sugarcane (Saccharum officinarum L.) lands in Hawaii. To determine the effects of varying environmental conditions on crop production and to validate an aroid simulation model developed earlier, taro was grown under rainfed conditions at two sites that differed in elevation (90 and 335 m) on Hawaii island and at four planting dates (Winter, Spring, Summer, and Fall) on 27 February, 28 May, 27 August, and 24 November 1992. Biomass harvests were conducted at bimonthly intervals. Using weather, soil, cultivar, and management practices in this field trial, the aroid crop simulation model predicted dry weight of plant components, leaf area index (LAI), and time to harvest maturity defined as leaf stage. Fresh and dry weights of corms increased linearly from 1 to 13 months after planting (MAP), indicating continuous partitioning to the storage organ. The increase in corm fresh weight was significantly greater for Spring + Summer plantings compared with Fall + Winter plantings, primarily due to lower incidence of corm rot. Due to its indeterminant growth, taro can be harvested between 6 and 13 MAP, depending on incidence of pests and soil and weather conditions that could cause early maturation. The aroid model simulated well the maximum LAI; however, it underestimated both potential dry corm yield and length of time to harvest maturity, indicating that further development of this aroid simulation model is needed.