Smooth Cayenne Pineapple Research Articles

Effect of Some Selected Organic Mulches on Flowering, Ripening and Suckering of Pineapple Va. Smooth cayenne

The gains obtained from organic mulching of pineapple farms can never be overemphasized. Despite this fact many developed countries still patronize synthetic mulching due to its efficiency in large pineapple farms. However in developing countries of Africa and Nigeria in particular where small scale pineapple farmers still contribute to the national gross domestic product (GDP), the need for cheaper organic mulching techniques which do not only suppress weed and improve soil fertility but have positive influence on pineapple flowering, ripening and suckering is required. Based on this, a research was carried out at the Teaching and Research Farm, Federal University of Technology Owerri to assess the effect of some selected organic mulch types on the maturing trends of Smooth Cayenne pineapple. A 32 factorial fitted into a Randomized Complete Block Design (RCBD) with three replications was used. Result showed that main effects from mulch rates and mulch types independently had significant influence on days to first flowering, days to 50% flowering, the interval between time of first flowering and attainment of 50% flowering, days to ripening, interval from flowering to ripening and number of suckers produced at 50% flowering stage while interaction of mulch rates and mulch types only had significant effect on days to first flowering. This study revealed that the utilized organic mulch materials had tremendous positive influence on flowering, ripening and suckering of Smooth Cayenne pineapple.

Kombinasi BAP dan NAA untuk Media Perbanyakan Nanas Varietas Smooth Cayenne, Toboali in Vitro

Toboali pineapple variety is a smooth cayenne variety because it contains high antioxidants in the form of vitamins A and C. In addition, it is a source of citric and malic acids, substances that can be used to enhance the taste of the fruit. Pineapple is a plant that is propagated with vegetative organs such as suckers, slips, and crowns. However, conventional propagation has a low propagation rate. Tissue culture is an in vitro technique used in the rapid propagation of plants and in large quantities to meet the needs of cultivation and research. The selection of regeneration media is very influential on the development of plants in tissue culture. This study aimed to obtain the optimal media combination with BAP and NAA in the regeneration of Smooth Cayenne pineapple (Toboali) in vitro for mass propagation of seedlings and genetic engineering research. This study used 6 levels of BAP, namely 0, 1, 2, 3, 4, 5 mg.L<sup>-1</sup> and 4 levels of NAA, namely 0, 1, 2, 3 mg.L<sup>-1</sup>. The treatment used was a combination of BAP and NAA as many as 24 treatments with 3 replications. The best pineapple regeneration medium for mass plant propagation in this study was BAP 3 mg.L<sup>-1</sup> without NAA media which produced the highest shoots of 17.33 shoots per explant at 12 week after planting. The best pineapple regeneration medium for genetic engineering research was a combination BAP 3 mg.L<sup>-1</sup> and NAA 2 mg.L<sup>-1</sup> media which produced 18.33 shoots per explant from embryogenic callus.

Yield and Yield Advantage of the Component Crops as Affected by Strip Intercropping of Coffee (<i>Coffea arabica</i> L.) with Pineapple (<i>Ananas comosus</i> L.)

Intercropping has a number of advantages over mono-cropping production system, which has significant problems and that there are sufficient justification for studying intercropping approaches. Consequently, researchers have proposed a systematic intercropping approach to evaluate the benefits of strip intercropping in terms of yield advantage, economic return, yield stability, pest control, nutrient use efficiency, etc. However, because of these advantages, intercropping is practiced in many parts of the world, especially in developing countries like Ethiopia. A field experiment was conducted at Awada Agriculture Research Sub-center during 2012 and 2019 to evaluate the effect of strip intercropping ratios of coffee with pineapple on the yield and yield components of both crops and to determine economically optimum coffee to pineapple strip intercropping ratio for the study area. The experiment was laid out in a randomized complete block design with three replications. Coffee variety (Fayate) and Smooth Cayenne Pineapple variety were used. The experiment was comprised five treatments: sole coffee, sole Pineapple, 1C:1, 1:2, and 1:3 ratio of coffee with pineapple. The pooled mean analysis revealed that the sole planted coffee and pineapple were produced statically highest yields in contrast with other intercropped treatments. Regarding strip intercropping treatments, the highest and lowest clean coffee yield were recorded at 1C:1P (1289 kg ha^-1) and 1C:2P (1128 kg ha^-1) treatments. The highest total land equivalent ratio was recorded at 1C:3P (1.50), closely followed by 4C:1P (1.36), 1C:1P (1.32), and 1C:2P (1.23) or a relative yield advantage of 23 to 50% was obtained from the coffee-Pineapple strip intercropping treatments. Therefore, this finding recommend that strip intercropping of coffee with pineapple at 1C:3P ratio is a viable option for sustainable productivity in yield and yield profit to farmers as revealed by the highest total LER.

Penyimpanan Mahkota Nanas dan Zat Pengatur Tumbuh pada Pertumbuhan Setek Basal Daun Asal Mahkota

The availability of pineapple seedlings in the field is a problem in the development of Smooth cayenne pineapple because of limited sources of planting material compared to the other types. Effort that can be done to solve the problem is to use the method of crown leaf-bud cutting. Propagation of pineapple (Ananas comosus L) with the method of crown leaf-bud cutting is not optimum so it can be optimized; one of them is by giving the duration of storage treatment and application of plant-growth regulators. The experiment was aimed to study the effect of crown storage duration and plant growth regulators on the growth of pineapple seedlings. The experiment was arranged in a nested plot design. Duration of crown storage for 2 (control), 10, and 20 days in room conditions at a temperature of 29-35°C and humidity of 46-70% as the main plot. The subplot was combination of indole-3-butyric acid (IBA) and 6-benzylaminopurine (BAP) with the concentrations: IBA 300 ppm and BAP 400 ppm, IBA 300 ppm and BAP 600 ppm, IBA 400 ppm and BAP 400 ppm, as well as IBA 400 ppm and BAP 600 ppm. The results of the experiment showed that the leaf-bud cuttings which stored for 10 days 57.34% were survived, 57.15% were sprouted, and 51.62% were rooted, while the control that survived, sprouted, and rooted did not reach more than 30%. The content of endogenous ABA in the crown leaf-bud shoots decreased significantly after being stored for 10 and 20 days, while the contents of endogenous auxins and cytokines were not different from the controls. Application of IBA 400 ppm combined with BAP 400 and 600 ppm increased the percentages of survived and sprouted cutting 1.5-1.7 times compared to control. Keywords: auxin, cytokines, exogenous hormone, endogenous hormone, vegetative propagation

JUS BUAH BERBASIS BIT MERAH (Beta vulgaris) PENAMBAHAN NANAS SMOOTH CAYENNE (Ananas comosus (L) merr.) SEBAGAI PANGAN FUNGSIONAL BAGI PENDERITA HIPERTENSI

Hypertension is an increase in systolic blood pressure, the height of which depends on the age of the individual affected. Red beet (Beta vulgaris) is one of the vegetables rich in inorganic nitrate, betalain, folic acid, riboflavin and potassium antioxidant compounds. Potassium and folic acid play an important role in the process of regulating blood pressure. The addition of pineapple aims to reduce the smell of the soil in red beets. In addition, pineapple also contains potassium and vitamin C which can help lower blood pressure. The purpose of this study was to determine the organoleptic quality, potassium levels and antioxidant activity of red beet juice (Beta vulgaris) by adding smooth cayenne pineapple (Ananas comosus (L) merr.) To patients with hypertension. This research is a RAL study (Completely Randomized Design) with three levels of treatment, namely the ratio of red bits to pineapple, P1 (100: 37.5), P2 (100: 50) and P3 (100: 62.5). Organoleptic quality analysis descriptively and Kruskal Wallis with Mann Whitney follow-up. Potassium test using the Spectometry test and the antioxidant activity test using DPPH Spectometry and converted to IC50. Chemical quality analysis using One-way ANOVA with Duncan's Multiple Range Test. The results showed that the addition of smooth cayenne pineapple had a significant influence on the quality of organoleptic juices. The panelists' acceptance of organoleptic quality of juice (smell, taste and color) tends to be favored. The level of potassium juice increased by an average of 468-1128 mg/ 100ml, the antioxidant juice activity on average was weak to moderate (166.9-101.4 µg/ml). The best treatment level is P3. Further research is needed on the use of pineapple humps, to increase antioxidant levels, and the addition of pineapple or other types of fruit is needed to increase the acceptability of juice.

Effect of Explants Length and Segmentation and Separated and Cluster of Shoots on the in vitro Shoot Formation and Growth of Pineapple (Ananas comosus L. Merr.)

Two experiments were conducted. In one, multiple shoots complex from Smooth cayenne pineapple stock cultures were cut into cluster of two, three, four shoots and were also separated into individual shoots of different length 5, 10, 15, 20 and 25 mm long and cultured on agar solidified MS medium enriched with benzylaminopurine (BAP) at 2.23 mg/l. In the other one, 25 mm long shoots were cut longitudinally into halves and quarters and cultured at density of one explant and 15 mm long shoots were cultured intact at density of one, two, three and four explants per culture. Longer (25 mm) intact and halved explants produced the highest (10 shoots) while 5 and 10 mm long explants resulted in lowest (6 shoots) and 15 and 20 mm long explants resulted in an intermediate (8 shoots) shoot formation. Shoot formation whether the explants were cultured as separated intact or as cluster of shoots decreased from 10 to 4 shoots per explant as the density increased from one to four. Shoot length was not affected by using of separated intact explants of different length. However, increasing the explants density increased the shoots length particularly when cluster rather than separated shoot were used as explants.

Effect of peatmoss and sand mixing ratio on the acclimatization of Smooth cayenne pineapple (Ananas comosus (L) Merr.).

Abstract The effect of peat moss and sand each alone and in 8 different mixing ratios (5 part of peatmoss mix with 1, 2, 3, 4 and 5 part of sand and 1 part of peatmoss mix with 1, 2, 3, 4, and 5 parts of sand) on the survival and growth of Smooth cayenne pineapple plantlets during acclimatization stage were compared. The highest plantlets survival (100 %) obtained in pots filled with sand alone (0 : 1) and mix of 1 part of peat moss and 3 parts of sand (1: 3) while the lowest survival (67 %) obtained on pots filled with 5 parts of peat moss and 3 parts of sand (5: 3). The tallest (120 mm) and heaviest (2.94 g) plantlets, on the other hand, obtained in pots filled with mix of 1 part peat moss and 4 parts sand (1: 4) and equal parts of sand and peat moss (1: 1) respectively while mixing of 5 parts of peat moss with 4 parts of sand (5: 4) resulted in the shortest (103 mm) and lightest plantlets (2.42 g). The difference of 33 % in plantlets survival among the various mixing ratio indicated that proper selection of substrate during acclimatization stage is very crucial for commerciality of any micropropagation system

Effect of Benzylaminopurine and Indole acetic acid in in vitro multiplication of pineapple (Ananas comosus L Merr) cv Smooth cayenne.

Abstract In vitro multiplication of Smooth cayenne pineapple was tested in agar solidified full strength MS medium containing 6-benzyleaminopurine (BAP) at 2.25, 3.25, 4.25 and 5.25 mg l-1 alone and in combination with indole acetic acid (IAA) at 0.75, 1.75, 2.75 and 3.75 mg l-1. BAP at 2.25 mg l-1 induced the highest shoot formation (9 shoots/ 60 days). Other combinations of BAP and IAA resulted in either less or an equal shoot formation as that of singly applied BAP at 2.25 mg l-1. Statistical analysis showed that the shoot formation was mainly controlled by BAP. IAA, on the other hand, had no direct effect on shoot formation. However, it interacted significantly with BAP. The IAA interaction with BAP could be of positive and negative natures depending on the concentrations of both hormones. Singly applied BAP at 2.25 mg/l was the best for multiplication of secondary explants of Smooth cayenne pineapple.

Study on Fiber Fineness of Smooth Cayenne Pineapple Leaf

To determine the the fiber fineness in different parts of the old and young leaves. the pineapple leaf fiber of smooth cayenne was used as raw material, The results showed that, the length of fiber extracted from the old leaves of smooth cayenne pineapple ranged from 80 cm to 100 cm, and the average fiber fineness of the the tip and root were 14.40 dtex and 18.53 dtex, respectively. While the length of fiber extracted from the young leaves of smooth cayenne pineapple ranged from 50 cm to 70 cm, and the average fiber fineness of the the tip and root were 13.27 dtex and 14.77 dtex, respectively. Variance analysis reveals that the fiber fineness of root and tip in the old pineapple leaf showed significant difference (P<0.05) in smooth cayenne pineapple.

Predicting the Consumer Acceptability of Dried MD2 and Smooth Cayenne Pineapple Pulps from Chemical Composition

Drying of pineapple (Ananas comosus) pulp enhances shelf life while assuring all-year-round availability of pineapple in different forms. The difficulty in selecting suitable fruit pulps for producing acceptable dried pulp needs to be addressed in order to reduce variability in dried pineapple pulps and predict consumer acceptability. MD2 and Smooth cayenne fruits were used for the study. Relationships existing between chemical and sensory characteristics of oven-dried pineapple pulps were determined using standard procedures. While a strong positive correlation was found between total soluble solids (TSS) and taste (SC=0.98; MD2=0.99) a negative association was found between TSS and crispness (SC=-0.98; MD2=-0.99) as well as between total titratable acidity (TTA) and taste (SC=-0.99; MD2=-0.98). The study showed that TSS of the fresh fruit was the single most important predictor of overall acceptability of dehydrated pulps. TSS of fresh fruits could therefore be used to select fresh pulps for dehydration.

Regeneration of pineapple (Ananas comosus L.) plant through somatic embryogenesis

An efficient protocol for a complete plant regeneration by somatic embryogenesis was developed with Smooth Cayenne pineapple (Ananas comosus L.). Previous works showed that this species is responsive to somatic embryogenesis. In the present work the influence of components of culture medium in the induction, development and conversion of somatic embryos was investigate in order to establish a somatic embryogenesis protocol. Nodular callus (83.67%) was initiated from leaf explants of young plants on CIM3 medium. The highest frequency (37.6%) of embryogenic callus induction was obtained from 4-week-old calluses on EIM3 medium supplemented with 3.0 mg/l picloram. The highly organized callus induction and the development of somatic embryos were achieved after the transfer of callus clumps onto EIM3 medium containing 1.0 mg/l BAP + 0.1 mg/l NAA. The frequency of somatic embryo formation was of 39.5 ± 2.45 embryos per callus. Up to 97% of the somatic embryos were converted into complete plants within 4 week on MSB medium with 1.0 mg/l BAP + 0.05 mg/l GA3 + 500 mg/l glutamine. The continuation of the elongation of the shoots occurred on this medium). Shoots obtained from all the above methods were rooted in MSB medium with activated charcoal. Complete plantlets were transferred onto specially made polyethylene bags containing soil mixture and transferred to the greenhouse. Survival rate of the plantlets under ex vitro conditions was 98% and maximum average number of plantlets (80 ± 0.6). The well-developed plantlets were transferred to an open field where the plants produced normal fruits.

ADUBAÇÃO FOLIAR NA QUALIDADE E PRODUTIVIDADE DE ABACAXI

There are just a few studies using foliar sprays with micronutrients on pineapple crops. The objective of this study was to evaluate the B and Zn effect, as chelate, acid or salt, via foliar feeding, on fruit yield and quality. The experiment was carried out in Guaraçaí, São Paulo State, Brazil, in a loamy medium texture soil, by using Smooth Cayenne (Hawaiian) pineapple seedlings. A randomized block design with four replications was adopted, with 110 g ha-1 of B and 250 g ha-1 of Zn for each application. Two foliar sprays were applied, at 7 and 9 months after planting. The B and Zn sources did not affect the total soluble solids contents, titratable acidity, average fruit diameter, fruit length without crown, and maturity index. Only the B, Zn, and K concentrations in the leaves were influenced by the application of micronutrients.

Quality optimisation of combined osmotic dehydration and microwave assisted air drying of pineapple using constant power emission

Combination of osmotic dehydration with microwave assisted air drying offers increased flexibility for process control and product quality. Osmotic dehydration (55°Brix solution at 40°C for 90min) combined with microwave assisted air drying (MWAD) was tested on smooth cayenne pineapples. The influence of the four most relevant processing parameters (osmotic treatment time, microwave power, air temperature and air velocity) was studied using a 24 circumscribed central composite experimental design. The product quality was evaluated in terms of charred appearance at the surface, moisture content, soluble solids content, water activity, firmness, colour and volume. Microwave power and air temperature were the two most important processing parameters that influenced the quality of the dehydrated pineapple, with the parameters most affected by the operating conditions being water content and percentage of charred pieces. Only in the latter was a significant quadratic effect found, all others were approximately linear. There was also a significant interactive effect between microwave power and air temperature affecting the percentage of charred pieces. Model predictions using a quadratic surface for water content and % charred pieces were validated with an additional experiment. Quadratic models were used to indicate optimum drying conditions for various targets.

Effects of sulphiting and osmotic pre-treatments on the effective moisture diffusion coefficients D<sub>EFF</sub> of air drying of pineapple slices

Air dehydration of fruits has been reported to be limiting in some factors especially on the drying kinetics and quality of the dried fruits. Removal of moisture during drying is attributed to these. This study was designed to evaluate the effects of sulphiting and osmotic pretreatments on effective diffusion coefficient (Deff) of air drying pineapple slices at 50o and 70 oC temperatures. Smooth cayenne pineapple obtained from Ajanla farms, Ibadan, Nigeria was used for the study. The fruits were hand peeled and sliced to spherical slices of 5 cm radius and 0.5 cm thickness. Pineapplefruit slices were pretreated at three levels of sulphiting and sucrose/osmosis and two conditions of drying (50 oC at 16 h and 70 oC at 10 h), resulting in 18 treatments in a factorial experimental design. Changes in moisture were monitored hourly and Fick’s second law was used to describe the rate of moisture transfer to determine the Deff as the slices were dried using a cabinet dryer. Results showed that the Deff was strongly affected by sulphiting at 2500 ppm equalling 9.10+ 0.13 x 10-6 and 6.78 + 0.53 x 10-6cm/s for 70 oC and 50 oC drying temperatures, respectively. The osmotic pretreatment at 40% sucrose recorded 4.91 + 0.15 x 10-6cm/s and 6.93 + 0.03 x 10-6cm/s for 70 oC and 50 oC drying temperature respectively. The control samples had 3.14 + 0.23 x 10-6 and 4.19 + 0.21 x 10-6 at 70 oC and 50 oC drying temperature, respectively. The high values obtained from the pretreated samples may be due to the restructuring of the cell walls. The combination of sulphiting and osmotic pretreatments also exhibited significant impact on the Deff value, ranging between 5.13 to 8.42 x 10-6, though not as pronounced as with the single pretreatment method. Furthermore, drying at 70 oC influenced the Deff value more than drying at 50 oC with both pretreatment methods. The study, therefore, showed that pretreatment methods improved the Deff of the pineapple slices, with the sulphiting pretreatment at 2500 ppm having the highest value.Key words: Sulphiting, osmotic, pretreatment, drying, kinetics

Air-Oven Drying of Pre-Treated Fruit Slices: A Promising Solution to Post-Harvest Losses

Reports have shown that over 25% of fruit are lost during their season and virtually out of the market during off season due to their high moisture content couple with poor preservation methods practiced in Nigeria. Smooth cayenne pineapple specie obtained from Ajanla Farms, Ibadan was used for the study. A two factor-factorial experimental design of 3-levels of 3 pre-treatment methods (sucrose, blanching and sulphiting) and 3-levels of drying conditions (80 C/8 h, 70 C/10 h and 50 C/16 h) resulting into 81 treatments o o o was used. The treatments were reduced to 18 by stratified sampling method from the results of the moisture and ascorbic acid content obtained from the pre-treated slices before drying. The slices were dried in a cabinet dryer; the moisture and ascorbic acid content of the dried slices were monitored during drying and after. All the samples exhibited combinations of falling and increase in drying with increasing in drying time. The dried slices were stored for 18 weeks, at which they were analyzed at 3 week intervals. The results obtained revealed that there were significant effects (p<0.05) of the pre-treatments on the ascorbic acid and moisture content of the dried slices. The 60%S/60 CB/2500ppm SO at 70 C/10 h had the least value of o o 2 moisture content of 8.75% and 25.16 mg/100 g of ascorbic acid. Furthermore, the results indicated that drying at 70 C/10 h is suitable for drying of pineapple slices than other drying conditions. During storage, o there was continuous reduction in moisture content during the early weeks of storage. However, after 9 weeks of storage the moisture content of the samples increased showing significant differences between the mean values of the samples at different weeks of storage. Though, the samples pretreated with SO2 showed a little variation over the storage period. Drying condition of 70 C/10 h and pre-treatment of 2500 ppm o SO /60% sucrose was found to have minimal reduction of quality and thus the most appropriate treatment 2 for air-oven drying of pineapple slices. The study therefore, recommends that production of pre-treated dried fruit slices could be used to reduce the enormous post-harvest losses of fruits.

Extração, atividade da bromelina e análise de alguns parâmetros químicos em cultivares de abacaxi

Diante dos riscos e das limitações advindos do cultivo exclusivo de abacaxizeiros Pérola e Smooth Cayenne e visando à variabilidade genética, o Estado da Paraíba estuda material genético diversificado: os híbridos Emepa-01, Imperial e MD-2. objetivando a caracterização destes novos híbridos, avaliaram-se alguns parâmetros químicos e a atividade da bromelina nas polpas e nas cascas de todas as cultivares. o abacaxi Smooth Cayenne apresentou o menor pH (3,44 para polpa e 3,91 para a casca) e a maior acidez titulável (0,56g de ácido cítrico para 100g de polpa e 0,52g de ácido cítrico para 100g de casca), sendo a cultivar mais ácida. Dentre as polpas, as dos abacaxis Pérola e Smooth Cayenne contiveram níveis de açúcares redutores, não redutores e totais significativamente maiores (p&lt;0,05) do que os híbridos, apesar de estes terem valores mais elevados (maior que 30,00) da relação sólidos solúveis e acidez titulável e, consequentemente, maior aceitação pelo consumidor. o extrato bruto da cultivar Imperial apresentou maior atividade proteolítica e teor de proteína tanto na polpa (56,41 U/ml e 7,50 mg de proteína/ml) quanto na casca (68,56 U/ml e 10,40 mg de proteína/mL). Para a atividade específica, a casca do abacaxi Pérola (10,01 U/mg de proteína) contém valor significativamente mais elevado que os encontrados nas demais amostras. No entanto, dentre as polpas, a da cultivar Imperial (7,49 U/mg de proteína) apresenta atividade específica significativamente superior (p&lt;0,05) às demais.

Leaf reddening disease of pineapple in Ghana

A disease of pineapple, which threatens production of the exportable Smooth Cayenne pineapple, is reported. The disease has been observed in several commercial plantings in the Akwapim South, Ga and Gomoa districts, respectively, in the Eastern, Greater Accra and Central regions of Ghana. Reddening of the leaves (often interspersed with diffuse, irregular chlorotic patches), leaf dieback and plastic-like leaf consistency are the major above-ground symptoms. Diseased plants have reduced root systems, but internal browning of the underground stem is absent, indicating non-involvement of vascular wilt organisms, which have so far not been isolated from such plants. Mealybugs and ants are sometimes, but not always, associated with diseased plants. Nematodes of the genera Pratylenchus, Aphelenchus and Helicotylenchus have been recovered, though infrequently, from roots and root zone soil of diseased plants. Based on these preliminary results and field observations, it is hypothesized that the new disease of pineapple in Ghana could be of complex etiology with nematodes perhaps constituting one major group of primary causal agents and stress factors (e.g. soil moisture stress, low soil fertility and weed competition) being either primary agents or pre-disposing factors. Ongoing studies seek to conclusively determine the etiology of the disease as well as some factors affecting its epidemiological development. Until this is done, it is proposed that the disease be simply referred to as “red leaf disease” of pineapple after its dominant and most readily recognized symptom. Control measures for the disease are much needed if production of pineapple for export is to be sustained. To the author’s knowledge, this is the first-published, detailed account of a disease of this nature in Ghana.

Effect of Explants Density on the in vitro Proliferation and Growth of Separated and Cluster Shoots of Smooth Cayenne Pineapple (Ananas comosus L. Merr.)

Multiplication rate was always used as the sole parameter for assessment of the optimal treatment for in vitro shoot formation. However, beside its effect on the shoot formation, different treatments had different impact on the production cost. Separated shoots and shoot cluster of different sizes (1, 2, 3 and 4 shoots per cluster) of Smooth cayenne pineapple were cultured at density of 1, 2, 3 and 4 separated shoots and 1 cluster on agar solidified full strength MS medium enriched with sucrose at 30 g L-1 and BAP at 2.25 mg L-1 for 2 months to investigate the effect of explants density and explant types on shoot formation per explant, total per liter and cost per shoot. Density of one separated shoot per culture resulted in the highest shoot formations per shoot (11 shoots) but lowest total shoot per liter (550 shoots) and highest cost per shoot (13 cents), while density of 4 shoots per culture resulted in lowest rate (4 shoots) but higher total per liter (1400 shoots) and lowest cost per shoot (10 cents). Cluster of two shoots had higher rate (7 shoots) and lower cost (16 cents) than cluster of 4 shoots (4 shoots and 20 cents) but both resulted in equal total shoot per liter (750 shoots). Separated shoot had higher shoot formation capacity, higher total per liter and lower cost per shoots than cluster of shoots and using of total per liter instead of rate per explant was the best parameter for selection of treatment of lower cost and higher shoots production. © 2009 Asian Network for Scientific Information.

Protease inhibitors and reproduction of reniform nematode in pineapple

AbstractEndogenous protease inhibitors (PIs) in the roots of Smooth Cayenne pineapple clones may affect the growth of the plant‐parasitic nematode Rotylenchulus reniformis. In pineapple, reniform population densities remain atypically near preplant levels for 6–9 months after pineapple planting. A potted plant experiment was conducted to determine if the PI present in pineapple roots affected nematode reproduction and possibly account for the observed nematode field population dynamics. Pineapple PI activity increased for the first 6 months after planting and was higher in nematode‐inoculated plants. Nematode reproduction, however, was not correlated to PI activity. In a second experiment, PI activity was concentrated in the portion of the roots nearest the pineapple butt where nematode population densities were highest. The behaviour of the PI in pineapple roots suggested a defensive role, such as systemic acquired resistance, against R. reniformis.

Effect of Benzylaminopurine (BAP) on in vitro Proliferation and Growth of Pineapple (Ananas comosus L. Merr.) cv. Smooth Cayenne

The effect of 6-benzylaminopurine (BAP) at concentration range of 0 to 3.75 mg L-1 applied at concentration difference of a fixed increment of 0.25 mg L-1 on the in vitro shoot formation and average and total of shoot length and weight per explant of smooth cayenne pineapple were evaluated. BAP significantly affected the average of shoot number, length and weight but did not affect the total length and total weight per explant. The maximum shoot formation (12 shoots/explant) occurred at 4 concentrations of BAP (1.75, 2.0, 2.25 and 3.5 mg L-1) while tallest (25 mm) and heaviest (0.60 g) shoots obtained on MS hormone free medium. Shoot formation pattern showed two sudden increases in shoot formation. The first occurred at 1.25 and second at 3.50 mg L-1 and two sharp declines at 2.5 and 3.75 mg L-1. Identifying of the concentrations with contrasting effect where an increase and decline in the shoot formation pattern occur provide an essential base from which an informative successful histological and biochemical studies could be designed to elucidate shoot formation mechanism. © 2008 Asian Network for Scientific Information.