Average Leaf Number Research Articles

Low-cost and reliable substrate-based phenotyping platform for screening salt tolerance of cutting propagation-dependent grass, paspalum vaginatum

BackgroundSalt tolerance in plants is defined as their ability to grow and complete their life cycle under saline conditions. Staple crops have limited salt tolerance, but forage grass can survive in large unexploited saline areas of costal or desert land. However, due to the restriction of self-incompatible fertilization in many grass species, vegetative propagation via stem cuttings is the dominant practice; this is incompatible with current methodologies of salt-tolerance phenotyping, which have been developed for germination-based seedling growth. Therefore, the performance of seedlings from cuttings under salt stress is still fuzzy. Moreover, the morphological traits involved in salt tolerance are still mostly unknown, especially under experimental conditions with varying levels of stress.ResultsTo estimate the salt tolerance of cutting propagation-dependent grasses, a reliable and low-cost workflow was established with multiple saline treatments, using Paspalum vaginatum as the material and substrate as medium, where cold stratification and selection of stem segments were the two variables used to control for experimental errors. Average leaf number (ALN) was designated as the best criterion for evaluating ion-accumulated salt tolerance. The reliability of ALN was revealed by the consistent results among four P. vaginatum genotypes, and three warm-season (pearl millet, sweet sorghum, and wild maize) and four cold-season (barley, oat, rye, and ryegrass) forage cultivars. Dynamic curves simulated by sigmoidal mathematical models were well-depicted for the calculation of the key parameter, Salt50. The reliability of the integrated platform was further validated by screening 48 additional recombinants, which were previously generated from a self-fertile mutant of P. vaginatum. The genotypes displaying extreme ALN-based Salt50 also exhibited variations in biomass and ion content, which not only confirmed the reliability of our phenotyping platform but also the representativeness of the aerial ALN trait for salt tolerance.ConclusionsOur phenotyping platform is proved to be compatible with estimations in both germination-based and cutting propagation-dependent seedling tolerance under salt stresses. ALN and its derived parameters are prone to overcome the species barriers when comparing salt tolerance of different species together. The accuracy and reliability of the developed phenotyping platform is expected to benefit breeding programs in saline agriculture.

Light environment control for reducing energy loss and increasing crop yield in plant factories

Energy utilization for plant lighting is one of the primary constraints of the development of plant factories. Most researchers overlook the impact of energy attenuation during the propagation process on energy efficiency utilization, and the redistribution process of energy lacks corresponding theoretical guidance. Based on the expansion of Bouguer’s law, a new strategy of environmental control is proposed to solve this problem by interfering the form of energy propagation and redistributing the energy. Through the method of environment control, we establish two different environments (by changing surface reflectance): high-reflection environment and high-absorption environment (resembling an unbounded space). Near the leaf canopy in the high-reflection environment, the photosynthetic photon flux density (PPFD) and illumination intensity are 116.15 μmol∙m−2∙s−1 and 7069 lx, respectively. In contrast, in the high-absorption environment, the values are significantly lower: 30.59 μmol∙m−2∙s−1 for the PPFD and 1815 lx for the illumination intensity. The results of further plant growth experiments show that the average weight and leaf number growth of lettuces increased by 4.12 and 3.22 times, respectively, in high-reflection environment. The growing status of plants is also better in the high-reflection environment compared with the high-absorption environment. The strategy of environmental control provides a new direction to reduce energy loss and increase crop yield in plant factories.

Effect of Cereals Type and Watering Level on Morphometric Characteristics, Herbage Yield and Proximate Compositions of Hydroponic Fodder

This research was conducted at Prof. Lawal Abdu Saulawa Livestock Teaching and Research Farm, Federal University Dutsin-Ma, Katsina State, Nigeria. The experiment was conducted to examine the effect of cereal type, levels of watering (volume of water), morphometric characteristics, herbage yield and nutritional quality of hydroponically sprouted fodder of three different cereals (Maize, Sorghum and Millet). A completely randomised design (CRD) was deployed with three replicates per treatment. Results obtained indicated that significant differences (P<0.05) were recorded in mat-depth and fodder yield among the cereals. However, no significant differences (P>0.05) were observed in plant height and average leaf number. Furthermore, significant differences (P<0.05) were noticed in leaf length and width. Results of the proximate compositions showed that significant differences (P<0.05) were recorded in crude protein and crude fibre content. It can, therefore, be concluded that sorghum with 900ml of water recorded the best mat-depth and fodder yield, followed by maize. It is, therefore, recommended that sorghum could be used for the production of hydroponic fodder with 900ml of water per day.

Characterization of plant growth promoting potential of 3D-printed plant microbial fuel cells

Plant-Microbial Fuel Cell (PMFC) is an emerging technology that converts plant waste into electrical energy through rhizodeposition, offering a renewable and sustainable source of energy. Deviating from the traditional PMFC configurations, additive manufacturing was utilized to create intricate and efficient designs using polymer-carbon composites. Concerning the agricultural sector, the effect of 3D-printed PMFCs on the growth and biomass distribution of Phaseolus lunatus and Ipomoea aquatica was determined. The experiment showed that electrostimulation promoted the average daily leaf number and plant height of both polarized plants, which were statistically proven to be greater than the control (α = 0.05), by energizing the flow of ions in the soil, boosting nutrient uptake and metabolism. It also stimulated the growth of roots, increasing the root dry mass of polarized plants by 155.44% and 66.30% for I. aquatica and P. Lunatus against their non-polarized counterpart. Due to the biofilm formation on the anode surface, the number of root nodules of the polarized P. lunatus was 51.30% higher than the control, while the protein content in the PMFC setup was 42.22% and 8.26% higher than the control for I. aquatica and P. lunatus, respectively. The voltage readings resemble the plants' average growth rate, and the polarization studies showed that the optimum external resistances in the I. aquatica- and P. lunatus-powered PMFC were 4.7 kΩ and 10 kΩ, respectively. Due to other prevailing pathways of organic carbon consumption, such as methanogenesis, the effect of polarization on the organic carbon content in soil is currently inconclusive and requires further study.

Eficiencia de diferentes tipos de inoculantes en el cultivo de soja

The inoculation of Bradyrhizobium specific for the soybean crop is an indispensable practice in the cultivation of this leguminous plant. In this study, traditional inoculation via seed was chosen. The experiment was carried out in a soil classified as red oxisol with medium texture in a completely randomized design (DIC), with 4 treatments and 7 repetitions. Each experimental unit was comprised of a 1m² plot, and the treatments analyzed were: Liquid inoculant (T1); Peat inoculant (T2); Liquid + peat inoculant (T3) and no inoculant (T4). The objective proposed in this study was to verify the need to use inoculants in soybean planting in areas where the crop has been cultivated for more than six years. According to the F test, there was a significant difference between the treatments, with T3 standing from among the others for root length, number of nodules and nitrogen concentration on the leaf. T2, although inferior to T3, showed better results than treatments T1 and T4. In the experimental conditions using the Brasmax Bônus8579IPRO cultivar, there was a significant difference in the use of the products, with emphasis on the liquid inoculation + peat (T3), presenting a higher frequency concentration in the plant leaf, obtaining an even greater number of nodules and root length. As the value of the F statistic for the variables average root length, average number of nodes and average leaf transmit nitrogen content exceeds the critical value at the 1% probability level (4.72), they are represented at this level (P < 0 ,01). As the calculated F values were greater than the tabulated F values for the three analyzed variables, we rejected the null hypothesis (H0), and concluded that the determining variables have different effects. Therefore, we can conclude that the most recommended for inoculation would be the use both products.

In vitro Propagation of Endemic Species Mahonia Jaunsarensis Ahrendt Through Callus Culture.

Mahonia jaunsarensis Ahrendt (Family Berberidaceae) an endemic species was successfully propagated in vitro. An efficient propagation protocol has been developed first time. The callus cultures were established from leaf explants on Murashige and Skoog (MS) medium supplemented with 2,4-Dichlorophenoxyacetic acid (2,4-D; 1µM) and resulted 70% callus induction with green compact callus. When callus was transferred to MS medium containing Thidiazuron (TDZ; 0.75µM), maximum average number of shoot (3.06) produced but shoot length (3.37cm) and average leaf number (2.87) was increased upon transfer to MS medium containing N6-benzylaminopurine (BA; 6.0µM) plus α-naphthalene acetic acid (NAA; 0.5µM). In MS medium containing indole-3-butyric acid (IBA; 0.01µM), the maximum rooting percentage (56%) and average root number (2.56) per shoot and root length (3.33cm) were recorded. The rooted plantlets transferred in vermiculite + garden soil + farmyard manure (1:1:1) with maximum (55%) survival percentage under greenhouse condition. The phytochemical analysis of leaves obtained from tissue culture-raised plants revealed significantly higher levels of alkaloids (berberine and palmatine) than those obtained from wild plants. Similar trends were observed for antioxidant and antimutagenic activities. Results of this study offer a baseline for the conservation and sustainable utilization strategies forM. jaunsarensis.

Estimation of Genetic Variability for Yield and Yield Attributing Traits in Dolichus Bean [Lablab purpureus (L.) Sweet var. Typicus] Genotypes

Dolichos bean is an indigenous legume grown as vegetable (Lablab purpureus var. typicus) and pulse (Lablab purpureus var. lignosus) throughout India. A wide range of variation exists for the morphological and reproductive characters amongst the land races of Indian Bean grown all over the country. Therefore it is necessary to select variety having desired pod quality with high yield potential. Despite of these good attributing characters it is still regarded as underexploited vegetable because of low productivity, long duration and photosensitivity, flowering irregularity, growth habit and preference of consumers with respect to pod shape, pod size, pod colour, pod aroma. Keeping this in view the present investigation was conducted at All India Co-ordinated Research Project on Vegetable Crops, Odisha University Of Agriculture and Technology, Bhubaneswar during Rabi, 2020-21 for evaluating the yield and yield attributing characters, for estimating the variability, heritability, genetic advance and the association between yield and yield attributing characters for an effective selection to estimate the genetic variability in Dolichus bean [Lablab purpureus (L.) sweet var. typicus] genotypes for further crop improvement study. The genotypic variance ranged from 0.02 for pod weight per plant to 2435 for average leaf area. The phenotypic variance ranged from 0.023 for pod weight per plant to 2879.8 for average leaf area. Phenotypic coefficient of variation (PCV) was higher than genotypic coefficient of variation (PCV) for all the 14 characters taken. This happened because PCV estimates includes variations due to environment (E) and genotype and environment (GE) interaction. PCV was highest (60.31) for pod yield per plant followed by average leaf area (35.09) indicating the presence of wide range of genetic variability in the germplasm for these traits. Higher value of GCV was found for characters like pod yield per plant (59.80) followed by average leaf area (32.26) and number of pods per plant (31.94). Highest estimates of heritability in broad sense was observed in Pod weight per plant (98.30) followed by number of pods per plant (96.17), average leaf area (84.55), number of pods per inflorescence (83.91), pod length (82.22), plant height (78.82), pod yield per hectare (78.66) indicating that these characters are less influenced by environment.

IN VITRO MICROGRAFTING OF RED GLOBE (VITIS VINIFERA L)

This study was carried out to evaluate the micrografting success of Red globe cultivar (Vitis vinifera L.) on three rootstocks Ramsey, Freedom and SO4 and investigate the effect of some factors on the micrografting success. Furthermore, compatibility in the graft union was studied. The results showed that Red globe on un-rooted Freedom achieved the highest percentages of scion survival (100.00 %), scion bud burst (60.00%), graft union formation (60.00%), and rooting (40.00%), also longest shoot (2.00cm), highest root number (8.00) and root length (4.50cm). Murashige and Skoog (MS) medium Supplemented with Indole Butyric Acid (IBA) at 1mgL-1 achieved the highest percentages of scion survival (95.20%), scion bud burst (65.43%), graft union formation (82.22%) also, longest shoots (1.84 cm) and maximum average leaf number (2.50). Regarding the effect of MS strength, 25% MS, 50% MS and 75% MS achieved positive effects on all parameters compared with full MS. The anatomical study revealed that Red globe on Freedom combinations were the best due to enough callus formation, less necrotic layers, and a wavy continuity of new cambium were determined. Sterilized 1:1:1 (v:v) peatmoss+perlite+sand mix gave the highest survival rate (100.00%) and showed superior vegetative growth. Freedom micrografts achieved the highest survival rate (100.00%), better growth and longer roots compared with those on SO4 and Ramsey (80, 70%) respectively.

MICROPROPAGATION OF GRAPEVINE (VITIS VINIFERA L.) CVS. RED GLOBE AND SUPERIOR

This study was conducted to develop a protocol for micropropagation of grapevine (Vitis vinifera L.) cultivars Red globe and Superior by investigating their response to three media Murashige and Skoog (MS), Chee and Pool (C2D), and Woody Plant Medium (WPM) during the establishment stage besides study the impact of four cytokinin types 6-benzylaminopurine (BA), 2-isopentyladenine (2iP), kinetin (Kin) and thidiazuron (TDZ) at various concentrations on the shoot multiplication as well as acclimatization of neoformed plantlets on several media. A completely randomized design (CRD) was used and data were analyzed by SASS 9.1. The results revealed that the WPM medium was optimum in terms of shoot length and leaf number (4.00 cm, 5.10) respectively. On the other side, Red globe gave the best results on both C2D and WPM media in average shoot length (4.38, 4.46 cm) and average leaf number (6.00, 5.42) respectively. In the multiplication stage and at 1 mgL-1, BA showed the longest shoot and leaf number (2.3, 6.67) respectively. While kin gave the maximum shoot length with a mean of 3.57 cm. Moreover, BA significantly at 1 mgL-1, 2iP at 2 mg L-1, Kin at 5 mgL-1 , and TDZ at 1 mgL-1 gave the highest values compared to other concentrations. Plantlets acclimatization results revealed that sterilized 1:1:1 (v:v) peatmoss+perlite+sand mix gave the highest survival rate (100.00%) and showed the best vegetative growth.

Effect of plant VOCs and light intensity on growth and reproduction performance of an invasive and a native Phytolacca species in China.

Invasive plants often pose great threats to the growth of co‐occurring native plant species. Identifying environmental factors that facilitate exotic plant invasion and native species decline are important. In this study, we measured the effects of plant volatile organic compounds (VOCs), light intensity, and their interactions on the growth and reproduction performance of indigenous Phytolacca acinosa, and invasive Phytolacca americana, which has largely replaced the former in China. VOCs of invasive P. americana and low light levels both had negative effects on P. acinosa morphological and reproductive traits (stem length, average leaf number, total number, and length of racemes), and biomass allocation (total biomass, and leaf and flower mass fraction); low light also affected photosynthesis‐related trait (specific leaf area) of P. acinosa. In contrast, VOCs of P. acinosa had no significant effect on P. americana, but low light levels adversely affected its morphological and reproductive traits (stem length, total number, and length of racemes) and biomass allocation (total biomass, stem, and leaf mass fraction). Interactions between plant VOCs and light intensity had no significant effects on P. acinosa or P. americana. Under all experimental treatments, stem length, average leaf area, total number, and length of racemes, Root/Shoot ratio, root and flower mass fraction of P. americana were higher than those of P. acinosa, while average leaf number, specific leaf area, and leaf mass fraction was lower. These results indicated that P. acinosa was sensitive to P. americana VOCs and low light, which might affect the growth of sympatric P. acinosa. P. americana was negatively influenced by low light, but higher plant height and more reproductive organ resource allocation relative to sympatric P. acinosa might contribute to invasion success.

Potassium Dihydrogen Phosphate (KH2PO4) and Kinetin Enhance The Growth of Dendrobium Sonia Somatic Embryos

The Dendrobium Sonia orchid is a hybrid orchid that has a high selling value. Therefore, efforts should be carried out to improve technology to reproduce and regenerate Dendrobium Sonia orchids. The objective of this study was to determine the best concentration of Potassium Dihydrogen Phospate (KH2PO4) and Kinetin for the growth of Dendrobium Sonia somatic embryos. The experiment was arranged in a completely randomized design with two factors consisting of 3 treatments namely medium without KH2PO4, KH2PO4 160 mgL-1, KH2PO4 170 mgL-1, KH2PO4 180 mgL-1, and without Kinetin, Kinetin 0,5 mgL-1, Kinetin 1 mgL-1, Kinetin 1,5 mgL-1. Parameters observed in this study were number of leaves, leaf length, and wet weight of plantlets. The data were analyzed by using The Analysis of Variance and further tested using Tukey Multiple Range Test (Tukey Test) (P=0.05). The results showed that KH2PO4 170 mgL-1 was the best concentration for multiplication of Dendrobium Sonia as shown by the parameters the diameters of number of leaves (4,41 sheet), leaf length (1,16 cm), and wet weight of plantlets (0,10 mg) and Kinetin 1 mgL-1 was the best concentration for multiplication of Dendrobium Sonia as shown by the parameters the diameters of number of leaves (4,05 sheet), leaf length (0,97 cm), and wet weight of plantlets (0,09 mg). By interaction, the addition of various concentrations of KH2PO4 and Kinetin significantly affected the number of leaves with the best treatment adding KH2PO4 160 mgL-1 and Kinetin 1 mgL-1 MS with an average leaf number of 4.99 strands.

Perbedaan Tinggi, Jumlah Daun, dan Diameter Batang Tanaman Jagung (Zea mays L.) pada Sistem Agroforestri Penanaman Lorong (Alley Cropping) dan Tumpang Sari di DAS Mikro Desa Tukad Sumaga, Kecamatan Gerokgak, Kabupaten Buleleng

Differences in Height, Number of Leaves, and Stem Diameter of Corn (Zea mays L.) in Alley Cropping and Intercropping of Agroforestry Systems at the Micro Watershed of Tukad Sumaga Village, Gerokgak District, Buleleng Regency. Degraded land as a result of land conversion has a very bad impact on the agro-ecosystem. Land conversion caused by the increasing needs of the population. The majority of the livelihoods of the people in Tukad Sumaga village are farmers. The availability of forage is very important to be maintained. Corn plants, in addition to their production in the form of corn, forage fodder on corn plants are very important for the availability of cattle feed. This research was conducted on 28 DAP maize (Zea mays L.) in alley cropping system and intercropping in the micro watershed of Tukad Sumaga Village. The results showed that the highest average plant height, leaf number, and corn stalk diameter were found in the alley cropping system namely 1.03 m, 7.31, and 1.59 cm. There was no significant difference between the height of corn plants in alley cropping and intercropping systems. There is a significant difference between the number of leaves and the diameter of the stems of maize in alley cropping and intercropping systems.

Use of Oyster Shell Ash of Crassostrea spp. in Mass Production of Sanitized Seedlings of Colocasia esculenta L. Schott by the PIF Method and Influence of Some Fertilizers during Their Growth in Acclimation

The scarcity of Colocasia esculenta L. Schott seeds available to cover the needs of farmers is attributed to the attacks of Phytophthora colocasiae Racib., a causal agent of taro blight. The direct impact of this pathogen is the lack of tubers for consumption and the near disappearance of monoculture taro plantations. To solve this problem, the objective of this work was to realize the mass production of sanitized seedlings of two cultivars of C. esculenta using the PIF method and to evaluate the influence of some fertilizers on the growth of these PIF plants during acclimatization. For this purpose, two cultivars (Makoumba and Ehkwan’fre) of C. esculenta were used. For each cultivar, 60 corm fragments with a mass of 500g were grown in propagators (absence and presence of oyster shell ash of Crassostrea spp.). Analysis of agronomic parameters was done during two months of culture in the propagators. Weaning of PIF plants was performed at the end of each month. During acclimation, five treatments were applied (control, arbuscular mycorrhizal fungi, Tithonia diversifolia leaf powder, Oyster shell ash and, dried cow dung) and their influence was evaluated on plant growth parameters during three months, then significant differences were identified by ANOVA via the Student Newman and Keuls test at 5%. The results obtained showed that the average number of buds emitted/corm was more significant in the presence of oyster shell ash. From the 120 corm fragments used, a total of 599 PIF plants were produced (246 and 353 PIF plants for the cultivars Makoumba Ehkwan’fre respectively). The maximum number of weaned PIF plants was recorded in the presence of Oyster shell ash. The average size of these plants varied significantly in the propagators depending on the growth substrates. In acclimation, principal component analyses performed showed a positive correlation between average leaf number and average leaf area in plants inoculated with AMFs at the third month of culture. Oyster shell ash propagator amendment stimulated the production of PIF Plants. The PIF technique used boosted seed production 4.99 times from the 120 corm fragments used.

A hydroponic-based efficient hardening protocol for in vitro raised commercial kiwifruit (Actinidia deliciosa)

Actinidia deliciosa is a commercially important plant receiving recognition because of its high nutritive value. This study presents an efficient protocol for the hardening of in vitro raised Actinidia deliciosa plants using a hydroponic method. Leaf explants inoculated on Murashige and Skoog (MS) medium supplemented with 5.00 μM 6-benzylaminopurine (BAP) and 1.00 μM α-naphthaleneacetic acid (NAA) resulted in 5.28 ± 0.14 shoots per explants and 8.33 ± 1.80 cm average shoot length. Rooting was achieved through half-strength MS medium supplemented with 1.5 μM indolebutyric acid (IBA) and 0.6 μM BAP. Maximum root number (12.76 ± 1.08) and 6.78 ± 0.25 cm average root length were recorded from plantlets using half-strength MS medium supplemented with 1.5 μM indolebutyric acid (IBA) and 0.6 μM BAP. In hydroponic system, an average root length of 22.40 ± 0.59 cm, average root number of 21.50 ± 1.24, average leaf number of 4.50 ± 0.40, and average shoot length of 9.71 ± 0.29 cm were observed in Hoagland & Arnon solution. The early development of shoots, roots, and leaves through hydroponics was advantageous in establishment of micropropagated plants in a greenhouse. Complete 100% plant survival was found by following proper acclimatization using hydroponic method. The study underlines the efficient hardening of micropropagated plants of A. deliciosa through hydroponic technique in Himalayan region.

Changes of root zone temperature, growth and productivity of broccoli cultivated with coloured plastic mulches

The main aim is to find out the influence of using coloured plastic mulches (blue, white, green, red, black and white on black) compared with a mulch-free treatment on the root zone temperature, growth and productivity of broccoli. The results indicated that the highest and lowest mean root zone temperatures were recorded the in the dark-coloured mulches (blue, green, red and white on black) and in the light-coloured mulches (white), respectively, in both the winter and spring seasons. The average shoot length, leaf number and root volume of the broccoli for all the treatments was higher in the spring season compared with those of the winter season. The highest marketable head fresh weight values were 449.6 and 451.0 g found in the black mulch, while the lowest values were 391.4 and 397.5 g found in the winter and spring seasons for the red mulch, respectively. The N, P, K, Ca and Mg concentrations in the broccoli heads ranged from 2.0 to 2.8%, 0.9 to 1.0%, 2.7 to 3.6%, 1.9 to 5.9% and 0.5 to 0.89%, respectively, for all the treatments.

Identification, Determination and Quantification of Indole-3-Acetic Acid Produced by Pseudomonas aeruginosa UPMP3 and Its Effect on The Growth of Oil Palm (Elaeis guineensis Jacq)

Pseudomonas species have founded as greatest and potentially most promising group of plant growth promoting rhizobacteria (PGPR). Pseudomonas aeruginosa UPMP3 is an important PGPR isolated from oil palm rhizosphere. This rhizobacteria is likely to synthesize and release phytohormone indole-3 acetic acid (IAA). Production of IAA is one of the main reasons to promote plant growth and yield. The aim of this study was to detect, identify and quantify the IAA production by P. aeruginosa UPMP3 in vitro and its influence on oil palm seedling growth. Nutrient broth medium supplemented with 1-5 mg/ml L-tryptophan and without L- tryptophan were used for bacterial culture. The pH levels of culture media were optimized under shaken and static conditions and incubated at 28±2°C in different incubation periods. The production of IAA by P. aeruginosa UPMP3 was extracted, purified, detected and quantified by Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC) analyses. Production of IAA was quantified by HPLC in liquid culture and achieved 12.08µg/ml with a retention time of 13.711 min. On the other hand, the maximum 52 µg/ml IAA was recorded in the medium supplemented with 4 mg/ml L- tryptophan in compare to control. The optimum pH level of the culture medium was recorded as 7 under shaken conditions at 150 rpm with 5 days incubation. The influence of IAA produced by the UPMP3 on oil palm seedling growth was carried out in the pot experiment. The germinated oil palm seedlings were treated with the extract of bacterial strain and observed a positive effect on seedling growth in respect to average root and leaf number, root, shoot, and leaf length compare to the synthetic IAA and the control.

Effects of Different Nutrient Solutions on the Acclimatisation of in vitro Caladium Plantlets using a Simplified Hydroponic System

An efficient acclimatisation protocol is critical to improve the survival rate and promote growth of in vitro plantlets. Herein, tissue-cultured plantlets of ‘Red Flash’ caladium (Caladium × hortulanum Birdsey) were treated with deionised water and three nutrient solutions including Japanese garden formula (JG), South China Agriculture University formula B for leafy vegetables (SCAU-B) and Hoagland solution in a simplified hydroponic system under indoor environmental conditions. The results showed that all the plantlets survived after 30 days of hydroponic culture, and the three nutrient solutions showed significant positive effects on the plant growth and the content of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, soluble sugar and soluble protein compared to the deionised water treatment. No significant difference was recorded for the other growth parameters except the average leaf number per plantlet among the nutrient solution treatments. For the analysed physiological parameters, the plantlets treated by SCAU-B contained significantly higher content than those of the Hoagland treatment except the protein content. No significant difference was found between the JG and the SCAU-B treatment except the carotenoid content, and between the JG and the Hoagland treatment except the protein content. The plantlets acclimatised in the nutrient solutions also had a good performance when transferred to plastic pots. These results implied that water alone was not capable of maintaining healthy growth of in vitro caladium plantlets, and hydroponics approach using the three nutrient solutions could be a feasible method for acclimatisation of the plantlets.

Plantlets Regeneration from Crown Bud Slicing of Pineapple (Ananas comosus)

Pineapple propagation by lateral shoots, suckers or crowns is often confronted with limited number of regenerated seedlings and high diversity in flowering and fruit formation. In order to solve this problem, this study offer an alternative method by using tissue culture techniques. This study aimed to determine the effect of growth regulators on plantlet regeneration from bud slicing of pineapple cv. Tangkit. Four levels of 2.4-D (0.0, 0.001, 0.01 and 0.1 ppm) in combination with BA (0.0, 0.1, 1.0 and 10.0 ppm) were tested on solid MS medium. Cultures were incubated in total darkness for a week followed by transfer to 16-hour photoperiod. Results showed that explants treated with 2,4-D and/or BA succeeded in regenerating adventitious shoots. Average leaf number did not differ significantly among treatments (P = 0.60). Highest leaf number (2.99 ± 0.23) was obtained on medium with 0.01 ppm 2,4-D without BA, followed by 0.1 ppm 2,4-D without BA (2.85 ± 0.33). Meanwhile, roots were only formed on medium with 0.1 ppm 2.4-D without BA (4.2 ± 0.37 per shoot). Thus, complete plantlets were regenerated only on medium supplemented with 0.1 ppm 2,4-D without BA. The growth of plantlets was relatively uniform, and plantlet acclimatization succeeded 100% on Jiffy pots. The finding of optimum concentration of 2.4-D and BA in this study is important to develop standard protocol for in vitro propagation of pineapple cv. Tangkit. Thus, the benefit of producing seeds in large quantities and relatively uniform in growth is made possible through tissue culture technique.

Growth and Yield Response of Sweet Corn (Zea Mays Saccharata Sturt) on Some Green Manure Tithonia Diversifolia and Dose of Em4

Soil fertility decline as a result of the use of inorganic fertilizers. Tithonia diversifolia is an green manure and EM4 is a mixture of beneficial microorganisms. Application of Tithonia and EM4 on sweet corn is an effort to replace the use of inorganic fertilizers. This study aims to obtain the interaction in application of Tithonia and EM4, to compare at different doses of green manure Tithonia, and to compare on the application of multiple doses of different EM4. Completely Randomized Block Design is used which consist of two factors. The first factor is the dose of Tithonia consisting of: 0 tons ha-1, 10 tons ha-1, 20 tons ha-1 and 30 ton ha-1. The second factor is the dose EM4 comprising: 0 ml L-1, 10 ml L-1 and 20 ml L-1 of water. The results showed that Tithonia diversifolia and EM4 have no effect on the growth and yield of sweet corn. Tithonia diversifolia of 30 tons ha-1 provide the highest plant height and the highest number of leaves and and the largest stem diameter and the highest level of leaf greenish. There is a tendency on the ascending EM4 dosage, will increase the average plant height, leaf number, stem diameter and leaf greenish level. Keywords:Tithonia, EM4, sweet corn.

In vitro Plant Regeneration in Cleopatra (Citrus reshni Hort. ex Tan.) by Direct Organogenesis

Maximum shoot regeneration (87.85%) and number of shoots per explant in the epicotyl segments having longitudinal cut in Citrus reshni var. Cleopatra were obtained on MT medium supplemented with BAP (2 mg/l) + NAA (0.2 mg/l). Maximum shoot length (5.10 cm), average leaf number per shoot (12), leaf length (2.12 cm) and width (1.5 cm) in Cleopatra were obtained on MT medium supplemented with BAP (2 mg/l) + NAA (0.2 mg/l). The maximum in vitro rooting (78.88 %) in the excised shoots occurred in liquid medium on MS supplemented with BAP (0.5 mg/l) + NAA (0.5 mg/l).
 Plant Tissue Cult. & Biotech. 28(2): 251-260, 2018 (December)