Pineapple Growth Research Articles

Assessment of Land Suitability for Enhancing Key Crop Commodities: Pineapple, Coffee, and Mango

This study aims to evaluate land suitability for enhancing the production of key crop commodities in Ngancar District, Kediri Regency, particularly pineapple, coffee, and mango. The district has high soil fertility potential due to its location at the foot of Mount Kelud. The research methods include land surveys, soil sampling at depths of 0-30 cm and 30-60 cm, and laboratory analysis to measure soil physical and chemical properties. Results indicate that the land in the study area generally falls into the marginal suitability class (S3), with the main limiting factors being soil texture dominated by sandy loam, low K₂O levels, and high rainfall that affects pineapple growth. Slope gradient is also a limiting factor for coffee and mango cultivation. Adjustments in soil management, such as timely fertilization and planting crops with strong root systems, can improve the land's suitability potential. In conclusion, although the land in Ngancar District has certain limitations, optimizing land use can enhance the productivity of key commodities, particularly through improved soil management and appropriate fertilizer use. Keywords: Crop commodities, Land Assessment, Land Degradation, Mount Kelud.

Pineapple growth and development modeling based on nitrogen rate and planting density

Plant growth models, derived from reliable databases, enable development of software for recommending cultural practices, harvest predictions, and enhancing productivity. This study aimed to create, refine, and simulate reference models for pineapple growth and development, adapting them based on nitrogen supply per plant and plant density per hectare. We utilized a field test database with periodic assessments of root, stem, leaf, fruit, and stem diameter fresh and dry weight, along with climate data from meteorological stations in or near the experimental areas. These growth models were developed, considering significant correlations and high correlation coefficients, using both simple non-destructive (stem diameter) and destructive (fresh or dry weight of D leaf) plant evaluations, either separately or in combination. The resulting models can provide estimated predictions for pineapple growth, adaptable to varying plant populations and nitrogen fertilization rates (measured in grams of N per plant)

Training and Educating of Pineapple Farmers in Producing Organic Fertilizer Using The Bio-EM4 Application Technology in Lendang Nangka Utara Village, Masbagik, East Lombok

The aim of this community service activity is to train and mentor farmers to produce organic fertilizer from cattle pen waste to create a village community that is self-sufficient in meeting the fertilizer needs for its pineapple farming business. The activity used a participatory action method, which was carried out for 19 months. The results of the activities show that the implementation of the activities ran smoothly and successfully. Farmers' participation and enthusiasm, which was previously moderate, turned out to be increased to high after implementing direct assistance in the field. Farmers' knowledge and skills are increasing as evidenced by the fertilizer produced based on SNI standards which is classified as good quality. Organic fertilizer produced by farmers can be used as a substitute for Urea, ZK and TSP fertilizer because application of a dose of 25 tons ha-1 plus NPK Ponska dose of 100 kg ha-1 can balance the growth and yield of pineapple in plots fertilized with NPK dose of 500 kg ha-1 . So the recommended application dose for organic fertilizer produced by this program is 25 tons ha-1 plus NPK Ponska 100 kg ha-1 with the application time after soil processing.

Impact of the Combination of Chemical and Organic Fertilization on the Growth and Yield of Pineapple under Two Shade Net Conditions

The use of organic sources presents itself as a viable alternative to mitigate the excessive reliance on chemical fertilizers in agricultural practices. However, in the realm of pineapple cultivation, research exploring the synergy between chemical and organic fertilizers remains scarce. In this context, the objective of this research was to evaluate the impact of the combination of chemical and organic fertilizers on the growth and yield of the MD-2 pineapple cultivar under two shade net conditions (installed 45 and 250 days after planting). The experiment was conducted in a split-plot design, with the main plot being the shade net conditions and the sub-plots the five fertilization treatments, which were applied 18 times via drip irrigation (control, 100% chemical fertilization, 50% reduced chemical fertilization, organic fertilization, and a combination of 50% chemical fertilization with organic fertilization). The results showed that the early installation of shade netting 45 days after planting decreases the growth and yield of pineapple; thus, the use of shade netting at this age is not recommended. Regarding fertilization, the combination of 50% chemical fertilization with organic fertilization showed similar growth and yield values compared to 100% conventional chemical fertilization under both shade net conditions. Furthermore, this combination presented similar nitrate and potassium values in the plant and did not negatively affect malic acid content. Therefore, the use of organic fertilizers in pineapple cultivation is a promising strategy to reduce the excessive use of chemical fertilizers, and it could also improve soil fertility.

Growth and Export Performance of Pineapple from India: An Economic Analysis

The present study was undertaken to know the growth and export performance of pineapple. Pineapple (Ananas Comosus) is a tropical fruit belonging to the Bromeliaceae family, and it is commercially cultivated worldwide as a high-value crop. India is the sixth largest producer in the world. The objective of the study was to elucidate the growth and export performance of the Pineapple from India.The secondary data for analysis was collected from AGMARKNET, National Horticultural Board (NHB) and Agricultural and Processed Food products Export Development (APEDA). The results of the growth rate revealed a positive and increasing trend in pineapple exports from India during the study period, with an annual growth rate of 9.78 percent in quantity and 6.39 percent in value, which is significant at a five percent level of probability. The results of the Cuddy Della Valle index indicated that pineapple exports from India exhibit moderate instability, with values of 17.17 and 19.90 percent in quantity and value terms, respectively. It reveals that the average Nominal Protection Coefficient (NPC) value for pineapple was 0.53, indicating a moderate level of export competitiveness. Throughout the entire period, it is evident that India did not demonstrate competitiveness in pineapple exports, as indicated by the Revealed Comparative Advantage Index (RCA) values consistently being below unity and the Revealed Symmetric Comparative Advantage (RSCA) values being negative. The direction of the Indian pineapple trade was conducted using the Markov chain framework. Among the major importers, the United Arab Emirates stood out as one of the most stable markets with a high probability of retention at 0.624. Overall, Indian pineapple stands out as a reliable and competitive player in the global market, with a strong performance and potential for growth. Therefore, efforts should be focused on enhancing the quantity of exports while ensuring they meet the quality standards and align with the consumer preferences of other countries.

Effect of pineapple waste biochar and compost application on the growth and yield of pineapple varieties in Ghana

IntroductionBiochar is one of the commonly used soil amendments for sustainable agriculture. The effect of biochar on crop yields depends on the quality of the biochar, which is influenced by feedstock type and pyrolysis conditions. Sole application of pineapple waste biochar and compost, and their combination has not been rigorously investigated. In this study, we investigated the effects of pineapple waste biochar and compost applied solely or in combination on growth and yield of pineapple on a coastal savanna Acrisol in Ghana.MethodsThe split-plot design with three replications was used, with pineapple varieties as the main plot and fertilizer application rates as the sub-plots.Results and discussionThe results showed that sole application of biochar and compost or their combination as a soil amendment increased pineapple growth and yield as compared to the unamended soil. Biochar applied in combination with compost/or inorganic NPK (nitrogen, phosphorus, and potassium) fertilizer significantly increased plant height and the number of leaves of pineapple plant, which resulted in improved fruits yield of the three (sugar loaf, MD2 and smooth cayenne) pineapple varieties at maturity over control, sole application of biochar, compost and inorganic NPK fertilizer. The Smooth cayenne variety outperformed MD2 and Sugar loaf variety.ConclusionIn conclusion, the results revealed that biochar applied solely or in addition to compost or inorganic NPK fertilizer has the capability to enhance soil quality and improve pineapple yield. Application of biochar in combination with compost/or inorganic NPK improves pineapple growth and yield.

Effect of Auxin and Cow Urine as Nutrient Source on Pineapple Propagation through Crown in Soilless Culture under Protected Condition

The present study was aimed to investigate the effect of auxin and cow urine on rooting, survival and growth of pineapple through crown propagation with soilless culture under protected condition. The research was conducted in 2020 at the High-Tech Horticultural Park, College of Horticulture, Junagadh Agricultural University, Junagadh, employing a Completely Randomized Design (CRD) as the experimental design. Eight treatments were implemented, including Control (T1), IBA 400 ppm (T2), IBA 600 ppm (T3), IBA 800 ppm (T4), NAA 600 ppm (T5), NAA 800 ppm (T6), NAA 1000 ppm (T7) and Cow urine 15 % (T8). The results of this experiment revealed that IBA 600 ppm had a notable impact on various growth parameters. It exhibited the highest percentage of rooted crowns (94.44 %), length of root (5.58, 8.26 and 11.08 cm) at 15, 25 and 35 days, respectively, length of leaf (13.35, 16.27 and 19.67 cm) at 15, 25 and 35 days, respectively, no. of leaves (70.58, 80.28 and 91.06) at 15, 25 and 35 days, respectively. Furthermore, IBA 600 ppm significantly influenced the fresh root weight (16.46 g), dry root weight (7.77 g), fresh shoot weight (136.33 g), and dry shoot weight (57.67 g). Additionally, IBA 600 ppm demonstrated the highest survival rate (65.91%) and the lowest mortality rate (24.09%). While T6 gave maximum no. of roots (70.58, 80.28 and 91.06) at 15, 25 and 35 days, respectively. T8 gave minimum days required for root initiation (2.67 days). The use of IBA at 600 ppm for a brief dipping period, along with the utilization of NAA at 800 ppm for enhancing root formation, and Cow urine at 15% for accelerated rooting, can be recommended for promoting successful pineapple crown propagation.

Growth and instability analysis of pineapple in Shivamogga

Growth and instability analysis of pineapple in Shivamogga

Tecnologias para redução do uso de água no abacaxizeiro em região semiárida

ABSTRACT: In irrigated systems, the adoption of management methods like soil cover, polymers which absorb the water present in the soil and the utilization of shading screens can decrease the water consumption by the plants. This is achieved as these means protect the plant and soil against radiation and wavelengths of light undesirable for cultivation. However, for pineapple cultivation in the semi-arid climate regions, very little study has been done regarding these technologies. Hence, the present study conducted to assess the pineapple growth, production and quality when various kinds of soil cover, red shading screen and water absorption polymers are employed. To accomplish this, a field trial was performed utilizing four types of soil cover in the plots (plastic mulching; organic matter; organic matter + red shading screen 50%; plastic mulching + red shading screen 50% and the control (no cover).Two treatments were included in the subplots namely, either the absence or presence of a water-absorbing polymer in the planting hole (0.5 g per plant), arranged in subdivided plots. We adopted the Randomized Complete Block (RCB) , with three replications. The following aspects of the plants were studied: naturally flowering, stem diameter; leaf area index; D-leaf area and total leaf area; fruit weight with crown; fruit weight without crown; fruit length with crown; and fruit length without crown, as well as the traits of the post-harvest fruit, soluble solids, titratable acidity, pH and the soluble solids/titratable acidity ratio. Further, the productivity in t ha-1 and efficiency of water use (EUA) were ascertained. It was evident that the plastic mulching + 50% red shading screen favored the vegetative development and productivity of the ‘IAC Fantástico’ pineapple plants. The characteristics of the quality of the postharvest fruit were unaffected by the treatments. The shading screen reduced the percentages of natural flowering in the treatments which included organic matter + red shading screen 50% and plastic mulching + red shading screen 50%.

Identification of GA2ox Family Genes and Expression Analysis under Gibberellin Treatment in Pineapple (Ananas comosus (L.) Merr.).

Gibberellin (GAs) plays an important regulatory role in the development and growth of pineapple (Ananas comosus (L.) Merr.). Bioinformatics was used to confirm the differential expression of GA2 gibberellin oxidase gene AcGA2oxs in the pineapple genome, which laid the foundation for exploring its role in pineapple. In this study, 42 GA2ox genes (AcGA2oxs) were identified in the pineapple genome, named from AcGA2ox1 to AcGA2ox42, and divided into four groups according to phylogenetic analysis. We also analyzed the gene structure, conserved motifs and chromosome localization of AcGA2oxs. AcGA2oxs within the same group had similar gene structure and motifs composition. Collinear analysis and cis-element analysis provided the basis for understanding the evolution and function of GA2ox genes in pineapple. In addition, we selected different tissue parts to analyze the expression profile of AcGA2oxs, and the results show that 41 genes were expressed, except for AcGA2ox18. AcGA2ox18 may not be expressed in these sites or may be pseudogenes. qRT-PCR (real-time fluorescence quantitative PCR) was used to detect the relative expression levels of the GA2ox gene family under different concentrations of GA3 treatment, and it was found that AcGA2ox gene expression was upregulated in different degrees under GA3 treatment. These results provide useful information for further study on the evolution and function of the GA2ox family in pineapple.

The Growth Performance of Pineapple Seedlings Planted with Mycorrhizae and Different Rates of Phosphorus Fertiliser

Pineapple stands as a promising crop with potential for widespread cultivation across Malaysia. Nevertheless, factors like the elevated cost of fertilisers and certain environmental challenges have acted as obstacles to pineapple production within the country. The application of mycorrhiza presents an opportunity to curtail fertilisers usage and thereby mitigate environmental strain. This study seeks to assess the impact of mycorrhiza on pineapple growth and determine an optimal Phosphorus (P) fertilisers rate that complements mycorrhizal activity, all while enhancing pineapple growth. A randomised block design with six replications was employed. The study maintained a consistent mycorrhiza application rate of 5 g/plant but varied the Phosphorus fertilisers rate. Data on leaf length, plant height, fresh weight, and dry weight were collected and subjected to analysis. The study, conducted over a four-month period at UiTM Jengka, Pahang, culminated in results analysed through Microsoft Excel and MINITAB. Notably, Treatment 3 displayed the most robust growth performance across leaf length, plant height, and fresh weight. However, Treatment 5 emerged as the optimal choice for enhancing dry plant weight.

Potential of Phosphorus Solubilizing Purple Nonsulfur Bacteria Isolated from Acid Sulfate Soil in Improving Soil Property, Nutrient Uptake, and Yield of Pineapple (Ananas comosus L. Merrill) under Acidic Stress

This study aimed to (i) evaluate purple nonsulfur bacteria (PNSB) strains possessing the highest phosphorus (P) solubilizing capacity in field and (ii) determine the efficacy of PNSB biofertilizers in improving soil quality, P uptake, growth, and yield of pineapple cultivated in acid sulfate soil (ASS). A field experiment was conducted in a completely randomized block design with two factors, including the first factor as P fertilizer levels (0, 50, 75, and 100% P) based on recommended fertilizer formula (RFF) and the second factor as supplementation of biofertilizers containing P solubilizing PNSB (no inoculated PNSB, Rhodobacter sphaeroides W48, R. sphaeroides W42, and a mixture of R. sphaeroides W48 and W42). The results indicated that the supplementation of PNSB biofertilizers led to an increase of 25.3–33.9% in soluble P concentration in soil compared to control treatment. Among the selected PNSB strains, R. sphaeroides W42 and a mixture of the PNSB in biofertilizers solubilized all insoluble P fractions (Fe-P, Al-P, and Ca-P) and strain W48 in biofertilizers for Fe-P and Al-P. Furthermore, the supplementation of biofertilizers from R. sphaeroides W48 and W42 individually and their mixture raised plant height by 3.56–4.10% and available P concentration by 25.3–33.9%. Total P uptake in pineapple treatments with biofertilizers from mixed PNSB was 42.9% higher than that in the control treatment ( p < 0.05 ). Application of mixed PNSB strains can reduce 25% P of chemical fertilizer, but the pineapple yield rose over 12.1%. Both R. sphaeroides W48 and W42 are potent for use as crop yield enhancers to obtain the sustainable pineapple cultivation under acidic stress.

Improving Nitrogen Availability and Ananas comosus L. Merr var. Moris Productivity in a Tropical Peat Soil Using Clinoptilolite Zeolite

Pineapple cultivation in nitrogen deficient and acidic peat soils leads to poor growth, yield, and fruit quality of pineapples. A study was conducted to determine whether clinoptilolite zeolite (CZ) could improve soil nitrogen availability, growth, yield, and fruit quality of pineapples grown in drained peat soils. Laboratory leaching experiments were conducted to determine the effectiveness of CZ in controlling nitrogen loss from peat soils, whereas an ion-exchange resin method was used to determine nitrogen availability in pineapple cultivation. Treatments evaluated were: (i) different amounts of CZ (25, 50, 70, and 100%) + NPK fertilizer, (ii) NPK fertilizer, and (iii) peat soil only. The peat soils with CZ reduced ammonium and nitrate losses because of the sorption of ammonium within the lattices of the CZ via ion exchange. Co-application of CZ (25%) and NPK fertilizers was more effective in increasing soil ammonium availability, whereas the use of CZ (25% to 100%) improved nitrogen uptake and use efficiency, growth, yield, and fruit quality of pineapple because CZ could regulate the availability of nitrogen ions for pineapple uptake. The buffering capacity of CZ increased soil pH and facilitated organic nitrogen mineralization. The co-application of CZ and NPK fertilizers can be used to improve nitrogen availability and pineapple productivity in tropical peat soils.

Estimation of Crop Water Requirement of Pineapple (Ananas comosus (L.) Merr.) for Drip Fertigation

The experiment was conducted at the research farm of ICAR- Central Coastal Agricultural Research Institute, Goa, India during 2016–2019 to estimate the crop water requirement (CWR) of pineapple during different growth stages and compare the pineapple crop performance and economic viability at different irrigation systems. Crop water requirement of pineapple was calculated based on the consolidated weather data of 14 years and crop evapotranspiration (ETc) of pineapple at different growth stages using Penman-Montieth equation using CROPWAT 8.0 software. In the experiemtal location, maximum crop evapotranspiration was found in the month of May (81 mm month-1) and the minimum was in the month of July (25 mm month-1). Crop water requirement was the highest in April (0.67 litre day-1 plant-1). During the period of monsoon, irrigation was withdrawn due to sufficienct soil moisture situation. Performance of pineapple crop under different systems of irrigation viz., surface irrigation, drip irrigation and drip fertigation was studied and found that the highest plant height (76.90 cm), D leaf width (5.45 cm), number of leaves (43), D leaf weight (150.3 g) and fruit weight (2.35 kg) were in drip fertigation. An estimated yield of 96.80 t ha-1 was recorded under drip fertigation treatment followed by drip irrigation (90.99 t ha-1) and surface irrigation (76.45 t ha-1) treatments. The cost economics analysis of pineapple production under different treatments revealed that the highest gross returns (` 14.5 lakhs), net returns (` 7.9 lakhs) and B:C ratio (1.2) were in drip fertigation treatment. Adoption of drip fertigation system in pineapple crop under west coast agro-climatic conditions of Goa is helpful to enhance the crop growth and yield of pineapple and fetch good economic returns.

Effect of mulch types on soil moisture, soil fertility, growth and yield of pineapple (Ananas comosus) in hill zone of Assam

A field experiment was carried out in Hill Zone of Assam from 2017 to 2019 with the objective of identifying mulch types on soil moisture retention, soil physical and chemical properties, growth and yield of pineapple (Ananas comosus) grown in hill slopes under farmers’ field condition. The treatments consisting of mulching with black polythene, dhaincha (Sesbania aquleata) as mulch, frequent slashing of weeds, soil mulching (soil mounding) and farmers practice without any mulch as control were evaluated in a randomized block design. Soil moisture content at 0-30cm depth was significantly different among the mulching methods and highest value of 14.2% at 0-30cm depth at harvesting was recorded in black polythene followed by slashing of weeds (13.1) and minimum in farmers practice. Soil texture was not affected by various mulches but there was a decline in bulk density with mulching and minimum value of 1.23 kg m-3 was recorded under slashing of weeds. Higher organic carbon (8.8 g kg-1), available nitrogen (341.8 kg ha-1), phosphorus (9.5 kg ha-1) and potassium (100.6 kg ha-1) were recorded in organic mulches i.e. slashing of weeds and dhaincha. The highest yield attributing characters and fruit yield of 38.3t ha-1 was recorded in the black polythene treatment followed by dhaincha as mulch (36.5 t ha-1) and frequent slashing of weed (35.6 t ha-1). Soil mulching and farmers practice recorded significantly lower yield than other treatments.

Effect of mulch types on soil moisture, soil fertility, growth and yield of pineapple (Ananas comosus) in hill zone of Assam

A field experiment was carried out in Hill Zone of Assam from 2017 to 2019 with the objective of identifying mulch types on soil moisture retention, soil physical and chemical properties, growth and yield of pineapple (Ananas comosus) grown in hill slopes under farmers’ field condition. The treatments consisting of mulching with black polythene, dhaincha (Sesbania aquleata) as mulch, frequent slashing of weeds, soil mulching (soil mounding) and farmers practice without any mulch as control were evaluated in a randomized block design. Soil moisture content at 0-30cm depth was significantly different among the mulching methods and highest value of 14.2% at 0-30cm depth at harvesting was recorded in black polythene followed by slashing of weeds (13.1) and minimum in farmers practice. Soil texture was not affected by various mulches but there was a decline in bulk density with mulching and minimum value of 1.23 kg m-3 was recorded under slashing of weeds. Higher organic carbon (8.8 g kg-1 ), available nitrogen (341.8 kg ha-1 ), phosphorus (9.5 kg ha-1 ) and potassium (100.6 kg ha-1 ) were recorded in organic mulches i.e. slashing of weeds and dhaincha. The highest yield attributing characters and fruit yield of 38.3t ha-1 was recorded in the black polythene treatment followed by dhaincha as mulch (36.5 t ha-1 ) and frequent slashing of weed (35.6 t ha-1 ). Soil mulching and farmers practice recorded significantly lower yield than other treatments.

Dynamics of the weed community during pineapple growth in the Brazilian semi-arid region

The pineapple belongs to the family Bromeliaceae and is a slow-growing succulent monocot with a reduced superficial root system. For this reason, the interference of weeds in competition with this crop can cause significant losses to the production. One of the bases to elaborate a control strategy is the knowledge of the diversity of weeds that occur in the cultivated areas. The objective of this study was to identify the weed community during pineapple growth in a semi-arid climate region of Brazil. Weeds were collected 60, 120, 180, 240, 300, and 360 days after planting (DAP) the pineapple. These collections were made in three different plots every two months until floral induction, composed of three pineapple cultivars. The weed community found in the irrigated pineapple field, in semi-arid climate conditions, was mostly composed by species belonging to the families Amaranthaceae, Asteraceae, Convolvulaceae, Fabaceae, Malvaceae, and Poaceae. The highest diversity of weed species was found at 60 DAP. The species Ipomoea acuminata was present throughout the development of the pineapple and showed the highest importance value index in most of the periods evaluated during the pineapple growth.

First Report of Leaf Spot Disease of Pineapple Caused by Penicillium oxalicum.

Pineapple (Ananas comosusMerr.) is an economically important tropical fruit crop. In China, it is primarily distributed in tropical and subtropical southern regions, including Leizhou Peninsula (Guangdong province) and Hainan province. Other pineapple culturing areas also include Fujian, Guangxi, Yunnan, and Taiwan provinces.A pineapple leaf spot disease was observed in Leizhou Peninsula (N20°47'52″,E 110°5'7″) from July to August in 2019-2020, with a natural incidence of 10 to 15%. In the initial infection stage, grayish or yellowish white spots emerged on the leaf surfaces with dimensions 1.25-1.75 × 0.8-1.0 cm. The leaf spots also had distinctive light brown-to-reddish brown banding pattern on the edges. At the late stage of infection, the leaves with the spots withered and died, seriously affecting the plant growth. To isolate the pathogen, leaf pieces 5 mm in diameter were cut from the decaying edges. They were surface-sterilized with 75% ethanol solution for 30 s, washed with 0.1% sodium hypochlorite solution for 30 s, rinsed five times with sterile water, and placed on potato dextrose agar (PDA) medium. After incubation at 28°C for 6 days, the pathogen was purified using single conidial isolation for morphological and molecular characterization. All 25 isolates showed similar phenotypes. The colonies on PDA were green, circular, flat, and velutinous. Conidiophores were broom-shaped (16.35±1.30 μm). Conidia were colorless, unicellular, and kidney shaped (3.50-4.00 × 2.50-3.00 μm). Based on the morphological characteristics, the fungal isolates were tentatively identified as Penicillium species. From each culture, the internal transcribed spacer (ITS) region of rDNA and the partial β-tubulin genes of a representative isolate (ZN2019211) were amplified using ITS1/ITS4 and Bt2a/Bt2b primer pairs, respectively. The gene sequences were deposited in GenBank (accessions MT678576 for the ITS region and MT720907 for the Bt2 region) and were 100% identical to P. oxalicum Currie & Thom isolates (MN592913 for the ITS region; KX961250 for the Bt2 region). Based on their morphological and molecular characteristics, the isolates were determined to beP. oxalicum. Pathogenicity tests were conducted in three replicates by inoculating surface-sterilized leaves of pineapple. The leaves were wounded and inoculated with mycelium PDA plugs (10 × 10 mm) from 6-day-old cultures. Control leaves wounded in the same way were inoculated with sterilized PDA plugs (10 × 10 mm). Each of the three replicates comprised two whole plants and two leaves (including a control) per plant (Wu et al. 2016). The inoculated leaves were placed in a greenhouse (25 to 30°C). Six days post inoculation, symptoms similar to those observed in the field were observed on the inoculated leaves, but not on the controls; the same fungus was isolated both times from the infected leaves, confirming Koch's postulates. We also inoculated pineapple inflorescence and fruit, with or without injury, and observed that the pathogen could not cause pineapple fruit disease, but caused early senescence of the inflorescence after being dropped with 200 µl of a 104conidia/ml solution, although it did not affect subsequent flowering. P. oxalicum has been reported to cause blue mold disease in different plants (Paul et al. 2018; Liu et al. 2019; Tang et al. 2020; Picos-Munoz et al. 2011). However, to the best of our knowledge, this is the first report of pineapple leaf spot disease caused by P. oxalicumglobally,and the disease has become a potential threat to the growth and production of pineapple in China.

Gypsum supplies calcium to Ultisol soil and its effect on <i>Phytophthora nicotianae</i>, pineapple (<i>Ananas comosus</i>) growth, yield and fruit quality in lower single row bed under climate change issue

<abstract> <p>Lower bed single-row pineapple cultivation could protect pineapple from soil erosion during the rainy season and drought period; however, disease problems could arise as a result of water logging. Two experiments were conducted in Ultisol soil using a lower bed single row to investigate the ability of gypsum to provide soil calcium (Ca) to the pineapple plant, plant resistance to heart rot disease, and provide a better effect on crop growth and fruit quality. In the first trial, four levels of gypsum (0, 1.0, 1.5 and 2.0 Mg·ha<sup>−1</sup>) and dolomite (2 Mg·ha<sup>−1</sup>) were spread and incorporated into soil that had been saturated with <italic>Phytophthora nicotianae</italic> inoculums. In the second trial, gypsum treatments (0, 1.0, 1.5, 2.0 and 2.5 Mg·ha<sup>−1</sup>) were used as a basic fertiliser in the row between the single beds. <italic>P. nicotianae</italic> attacked all treatments at 6 weeks after planting (WAP), and at 10 WAP, the mortality of the dolomite treatment reached 63.8%, significantly higher than that of the gypsum treatments (3.3%–14.3%). In the second experiment, gypsum significantly increased plant weight from 3 to 9 months after planting (MAP), especially when applied at 1.5–2.5 Mg·ha<sup>−1</sup>. Fruit texture, total soluble solids (TSS), and titratable acidity (TA) were not significantly different between treatments, but they all met the standards for canned pineapple grades. The results showed that soil-applied gypsum before planting provides soil calcium, meets the plant Ca requirement during an early and fast growth stage, and is free of heart rot disease.</p> </abstract>

Pineapple biomass estimation using unmanned aerial vehicle in various forcing stage: Vegetation index approach from ultra-high-resolution image

Pineapple becomes number 4th highest fruit production in Indonesia in 2020 and is one of the mainstay export commodities. Estimates of pineapple production using high-resolution images from drones are extremely rare, whereas production estimates for popular commodities do not pay attention to plant growth stages. This study aims to estimate pineapple biomass using UAVs at various pineapple growth stages to obtain the best formulation. Aerial photographs were taken using the Quest UAV, equipped with visible light and near infra-red camera. Ultra-high-resolution aerial photographs were taken using a UAV with a multispectral camera then transformed into a vegetation index (GDVI, NDVI, OSAVI, and TDVI). Images were taken on land plots with plant forcing ages (F) F-5, F-4, F-3, F-3, F-2, F-1, F0, F+1, and F+2. The results show that each pineapple growth stage has a different index to estimate. GDVI can be used to estimate the age of pineapples at F-5, F-4, F-3, and F+1 stage, while OSAVI can be used for F-2, F-1, and F + 2 TDVI for F0. The validation test result using a paired t-test showed that the biomass data on the field's measurement results are no different from the estimate data, so the best vegetation index can be used to estimate biomass.