Yukio Ishimine

Growth, Yield and Quality of Turmeric (Curcuma longa L.) Cultivated on Dark-red Soil, Gray Soil and Red Soil in Okinawa, Japan

Abstract We evaluated growth, yield and quality of turmeric (Curcuma longa L.) cultivated in pots with dark-red soil (pH 5.2), gray soil (pH 7.4) and red soil (pH 4.4) in Okinawa, Japan. The soils were collected from the 50-cm deep layer of the fields. We did not use any chemicals or organic fertilizers. Turmeric cultivated on dark-red soil had the highest plant height, root biomass and shoot biomass as compared with that cultivated on other soil types. Turmeric on dark-red soil had the highest yield with favorable color of the deep yellow and high curcumin content (0.20%). Protein content of turmeric in dark-red soil was 5.2%, which was around 40% higher than that in other soil types. Turmeric cultivated on dark-red and gray soils had a fat content 71% higher than that in red soil. The content of Ca, K and Mg was the highest when turmeric was cultivated on gray soil, and Fe was the highest when cultivated on dark-red soil. To gain a high yield and high contents of curcumin, fat, protein and Fe, we should cultivate turmeric in dark-red soil in Okinawa. We could not recognize the specific soil factor(s) required for high yielding and high quality of turmeric; however, it seems that a proper combination of soil factors, nutrients and/or pH level may be necessary to gain a high yield and high quality.

Effects of Application of N, P and K Alone or in Combination on Growth, Yield and Curcumin Content of Turmeric (Curcuma longa L.)

Crops respond differently to different fertilizer elements, and proper fertilizer management for a plant species is important for increasing yield and quality. Nitrogen (N), phosphorus (P) and potassium (K) are the three major nutrients, which individually and/or together maintain growth, yield and quality of plants (Mazid, 1993; Ivonyi et al., 1997). N is involved in chlorophyll formation, and it influences stomatal conductance and photosynthetic efficiency (Mazid, 1993; Ivonyi et al., 1997). N is responsible for 26-41% of crop yields (Mazid, 1993; Maier et al., 1994, 1996). K plays catalytic roles in the plant rather than becoming an integral part of plant components. It regulates the permeability of cell walls and activities of various mineral elements as well as neutralizing physiologically important organic acids. Plants with an inadequate supply of K show poor fruit or seed formation, yellowing of the leaves, poor growth, and low resistance to coldness and drought (Oya, 1972). A sufficient supply of K promotes N uptake efficiency of plants due to its stimulant effect on plant growth. P indirectly promotes plant growth and absorption of K as well as other nutrients (Oya, 1972). Turmeric (Curcuma longa L.) is used in many countries as a spice and cosmetic (Ishimine et al., 2003; Hossain et al., 2005a, b). It is now a popular medicinal plant worldwide. Curcumin the main component of turmeric functions as a medicine with anti-inflammatory, anti-mutagenic, anti-carcinogenic, anti-tumor, anti-bacterial, anti-oxidant, anti-fungal, anti-parasitic and detox properties (Hermann and Martin, 1991; Osawa et al., 1995; Sugiyama et al., 1996; Nakamura et al., 1998). The efficacy of C. longa found on a specific disease varies with the studies, and in some cases no efficacy was found (Hermann and Martin, 1991; Osawa et al., 1995; Sugiyama et al., 1996; Nakamura et al., 1998). Such differences may be due to variation in the curcumin content which is assumed to depend on the fertilizer elements. Turmeric is a horticultural crop demanding heavy fertilization for increasing yield and quality (Reddy and Rao, 1978; Govind et al., 1990; Yamgar et al., 2001). We reviewed several papers and found that the chemical fertilizers affect growth, yield and quality of turmeric variously, and the effects of N, P and K alone or in combination are not clear, because farmyard manure was used together and some experiments did not include control treatment (Reddy and Rao, 1978; Govind et al., 1990; Yamgar et al., 2001; Behura, 2001). Turmeric is commercially cultivated in Okinawa, but yield per unit area and curcumin content are very poor, because fertilizer management is not well known to the farmers (Hossain and Ishimine, 2005). In previous studies, we evaluated planting depth, time, pattern, seed size and soil types on growth and yield of turmeric in Okinawa (Ishimine et al., 2003, 2004; Hossain et al., 2005a, b; Hossain and Isimine, 2005). The present study was undertaken to evaluate the effects of N, P and K alone or in combination on growth, yield and curcumin content of turmeric.

Optimal Planting Depth for Turmeric (Curcuma longa L.) Cultivation in Dark Red Soil in Okinawa Island, Southern Japan

Abstract Effects of planting depth on emergence, growth, development and yield of turmeric (Curcuma longaL.) in dark red soil (Shimajiri Mahji) were evaluated in Okinawa, Japan. Turmeric planted at the depths of 8, 12 and 16 cm emerged earlier and more evenly than that planted at a shallower depth in both glasshouse and field experiments. Weed growth was unaffected by the planting depth of turmeric until 50-60 days after planting (DAP), but affected thereafter due to mutual shading with the canopy. Weed biomass at 90-140 DAP was significantly smaller in the fields where turmeric was planted at the depths of 8, 12 and 16 cm than in the field where it was planted at a shallower depth. The turmeric rhizome (yield) developed earlier when planted at 8, 12 and 16 cm depths than at 4 cm. In a glasshouse study, shoot biomass and yield of turmeric were significantly greater when planted at the depths of 4, 8 and 12 cm than that of 2 cm. In field experiments, they were also significantly greater when planting depth was 8 or 12 cm than 4 cm. Even in turmeric planted at a 16 cm depth shoot dry weight and yield were greater than that planted at a 4 cm depth, but it was comparatively difficult to harvest rhizomes in this field. About 30% of turmeric in the field planted at a 4 cm depth was uprooted by a typhoon, but not at the depths of 8, 12 and 16 cm. The over all results suggested that rhizomes of turmeric should be planted at a depth of 8 to 12 cm in dark red soil for a higher yield and lower weed competition.

Effects of Planting Pattern and Planting Distance on Growth and Yield of Turmeric (Curcuma longa L.)

Abstract The effects of planting pattern and planting distance on the growth and yield of turmeric (Curcuma longa L.) were examined in Okinawa Prefecture situated in southern Japan. The dry weights of shoot and rhizome (yield) of turmeric planted in a triangular pattern were heavier than those planted in a quadrate pattern. A 30-cm-triangular planting resulted in the heaviest shoot and rhizome yield among the planting patterns examined. Dry weight of shoot per unit land area (m2) was significantly heavier when planted at a 20- and 30-cm spacing than when planted with a larger spacing, whereas the highest yield was obtained when planted at a 30-cm spacing followed by 20- and 40-cm spacing. When turmeric was planted at a 20-cm spacing, rhizome could not expand properly, which ultimately resulted in the smaller rhizome compared with that planted with a larger spacing. The highest turmeric yield coupled with the lowest weed biomass was obtained on the two-row ridge in a 75-100 cm width compared with a one- or two-row ridge in a larger or smaller width. This study indicates that for reducing weed interference and obtaining higher yield, turmeric should be planted in a 30-cm-triangular pattern on two-row ridge in a 75-100 cm width.

Effects of farmyard manure on growth and yield of turmeric (Curcuma longa L.) cultivated in dark-red soil, red soil and gray soil in Okinawa, Japan.

Chemical fertilizer, herbicide and pesticide used in agriculture for increasing yield and controlling weeds and pests can contaminate the water, air and food, decrease soil fertility, inhibit growth of soil microorganisms and hazard human health (Sharifuddin and Zaharah, 1991; Li et al., 1999; Neera et al., 1999; Erisman et al., 2001). In addition, chemicals may destroy many species of plants, insects, fishes and soil microorganisms (Fantroussi et al., 1999). Therefore, utilization of farmyard manure in agriculture is recommended for retaining productivity of problem soils, reducing the usages of chemical fertilizer, improving economy in agriculture and minimizing environmental problems (Sharifuddin and Zaharah, 1991; Neera et al., 1999; Whalen et al., 2003; Xiao et al., 2006). Turmeric is a horticultural root-crop that is important not only as a spice and cosmetic, but also as a medicinal plant worldwide (Hermann and Martin, 1991; Osawa et al., 1995; Sugiyama et al., 1996; Nakamura et al., 1998; Ishimine et al., 2003; Hossain et al., 2005a, b). Considering the medicinal values of turmeric and environmental problems caused by chemicals application, it is important to cultivate turmeric using organic fertilizer (e.g. farmyard manure). Farmyard manure is regularly applied to many root crops for higher yield (Vanek et al., 2003). The fertilizers derived from animals, plants and microorganisms, are usually called organic fertilizer or farmyard manure. Many kinds of farmyard manure are locally produced based on available natural resources. Chicken manure, goat manure and cow manure are commercially available in Okinawa. Turmeric is commercially cultivated in dark-red soil (Shimahiri maaji), red soil (Kunigami maaji) and gray soil (Jagaru) in Okinawa (Hossain and Ishimine, 2005). Previously, we evaluated planting depth, time, pattern, seed size and soil types on growth and yield of turmeric (Ishimine et al., 2003, 2004; Hossain et al., 2005a, b; Hossain and Ishimine, 2005). Here, we evaluated the effects of farmyard manure on growth and yield of turmeric cultivated in dark-red soil, red soil and gray soil.

Sex and ploidy of anther culture derived papaya (Carica papaya L.) plants

SummaryTo improve the efficiency of papaya anther culture, we investigated (1) hormonal medium conditions for inducing haploids or dihaploids; (2) identified the sex of established plantlets using a sex-specific DNA molecular marker and (3) estimated their ploidy by flow cytometry analysis of DNA content. Anthers with a mixture of uninucleate, mitotic, and binucleate microspores were collected from a male plant, and cultured on MS agar medium with different concentrations of CPPU and NAA. An embryo induction rate of 13.8% was attained on MS agar medium with 0.01 mg l−1 CPPU and 0.1 mg l−1 NAA. The induced embryos were subcultured on medium with 0.0025 mg l−1 CPPU. Rooting of the developed shoots was promoted by treating their basal parts with 1500 mg l−1 IBA in a 50% ethanol solution for about 10 seconds. All the embryo-derived plantlets (27 plants) were identified as female, implying that they were derived from microspores. In addition, 26 plants were determined to be triploids and one to be tetraploids. We also observed a wide range of morphological variation (e.g., in tree height and fruit size) among the established plants. Based on the results, we discussed a potential value of anther culture techniques for the breeding of papaya.

Effects of Seed Rhizome Size on Growth and Yield of Turmeric (Curcuma longa L.)

Abstract Turmeric (Curcuma longa L ) plant species produces different sizes of daughter rhizomes (R) and mother rhizomes (MR), which are the only propagules (seed) for its cultivation. Here, we evaluated the effects of seed rhizome size on growth and yield of turmeric. Daughter rhizomes of 5-50 g (R-5 g~R-50 g) and mother rhizomes of 48-52 g (MR) were tested. The heavier the R up to 40 g, the better the plant growth, and the plants from the R-30 g, R-40 g, R-50 g and MR grew similarly well. The seed rhizomes with a greater diameter developed vigorous seedlings. The plants grown from R-30 g, R-40 g and R-50 g had a similar plant height, tiller number and leaf number, which were significantly higher than those from lighter R. The plants from R-30 g, R-40 g and R-50 g had a significantly larger shoot biomass and higher yield than those from smaller R in both the greenhouse and field experiments. R-50 g was easily broken at the time of planting, and had secondary and tertiary daughter rhizomes, which developed thinner plants and resulted in a lower yield. The shoot biomass and yield were highest in the plants grown directly from MR, and lower in the plants grown from daughter rhizomes attached to MR. This study indicates that the turmeric seed rhizome should be 30-40 g with a larger diameter, and seed mother rhizome should be free from daughter rhizomes.

Effect of NaCl on the Photosynthesis, Water Relations and Free Proline Accumulation in the Wild Oryza Species

Summary The physiological responses of wild Oryza species (Oryza latifolia Desv., a salt-tolerant species and O. rufipogon Griff., a salt-susceptible species) to salinity stress were investigated by comparing with check varieties of cultivated rice (O. sativa L.), SR26B (salt-tolerant) and IR28 (salt-susceptible). As the NaCl concentration of water culture solution was raised to 12 dS m–1 (about 113mM), leaf Na+ content per dry matter in wild Oryza species increased from 4 to 17 times as compared with the control (no NaCl treatment), whereas the accumulation was lower in cultivated rice varieties. The increased concentration of leaf Na+ resulted in the decrease in leaf water potential (Ψw) in all rice species, although the degree of decline in photosynthetic rate was different among the varieties. It was notable that the photosynthetic rate was cdmost constant in O. latifolia though Ψw decreased to – 2.0 MPa with the increased NaCl concentration in the water culture solution. A significant negative correlation between free-proline content and osmotic potential (Ψs) of leaf blade was found in both salt tolerant entries, SR26B and O. latifolia. In spite of higher leaf Na+ storage, the survival rate of O. latifolia was higher than that of SR26B, indicating that the mechanism of salt tolerance in O. latifolia may be different from that in SR26B.

Effects of Relative Light Intensity on the Growth, Yield and Curcumin Content of Turmeric (Curcuma longa L.) in Okinawa, Japan

Abstract The effects of relative light intensity (RLI) on the growth, yield and curcumin content of turmeric (Curcuma longa L.) were examined in Okinawa, Japan. The plants were shaded with white nets with different mesh sizes for maintaining respective RLI. Five RLI, 100 (without shading), 82, 79, 73 and 59% in 2004−2005 and four RLI, 100, 68, 52 and 48% in 2005−2006 were evaluated. In the first experiment, plant height increased markedly, but the number of leaves and tillers, and SPAD value increased slightly in the plants grown at 59−82% RLI compared with control (without shading). Turmeric shoot biomass and yield increased significantly at 59−82% RLI and they were highest at 73% RLI in the first experiment. Curcumin content of turmeric increased markedly at 59−73% RLI as compared with the control in the first experiment. Similar results in plant growth, shoot biomass, yield and curcumin content were obtained in the second experiment, but the effects of RLIs were smaller than in the first experiment because of late planting. This study indicates that turmeric is a partial shade-tolerant plant that could be cultivated at around 59−73% RLI for higher yield and curcumin content in Okinawa. However, the degree of RLI required for better turmeric cultivation may vary with the place, year and irradiance level.

Physio-Morphological Characters of F1 Hybrids of Rice (Oryza sativa L.) in Japonica-Indica Crosses: II. Heterosis for leaf area and dry matter accumulation

Summary A pot experiment was conducted to investigate the heterosis for morphological characters and to examine the relationship among some characters at active tillering, flowering and dough ripe stages of 12 Fj hybrids from crosses between japonica and indica rice. Heterosis for plant height, number of tillers, green leaf area and dry matter accumulation per plant was positive at all stages. The intensity of heterosis was higher at the active tillering stage for number of tillers, leaf area and dry matter accumulation per plant. A significant positive relationship was found between tiller number and leaf area per plant at active tillering and flowering stages. Significant positive relationships between leaf area and dry matter accumulation, and between tiller number and dry matter accumulation per plant were observed at all stages. A significant positive relationship was found between leaf area per plant at an early stage and dry matter accumulation per plant at a later stage, suggesting that early development of leaf area is an important factor for higher dry matter accumulation in 1 hybrids. Although heterosis for percent dead leaf blade was positive at the flowering stage due to early leaf senescence in some Fx hybrids, a larger leaf area was also found in Fx hybrids at this stage and leaves of Fx hybrids remained green longer compared to parent cultivars up to the dough ripe stage.