Friday, November 9, 2007

ABSTRACT


Istianto, M., K. Untung, Mulyadi, Y. A. Trisyono, and T. Yuwono. 2004.

The Compounds composition of sweet orange and pumello essential oils on some concentrations and their effects to the development of Panonychus citri McGregor (Acarina: Tetranychidae).

Panonychus citri is one of the most economically important citrus pests in Indonesia. One of the key success for managing the population of this pest is understanding the relationship between this mite and its host. However, information in this area is not well understood. The objectives of this research were to evaluate the influences of essential oil extracted from sweet orange and pumello fruit peels on the development and reproductive capacity of P. citri and to understand the mechanism responsible for the different effects that will be useful to develop management program. The research was conducted in the laboratory from February to July 2003 in Tlekung Batu Malang and Gadjah Mada University Yogyakarta. The treatments were 10, 20, 40, 80 ppm of essential oil, parafin and control. Each treatment was replicated 15 times and arranged in a completely randomized design. The results showed that the essential oil extracted from pacitan sweet orange and nambangan pumello fruit peels could inhibit the development and reduced the reproductive capacity of P. citri. The essential oils prolonged the life cycle and reduced the fecundity of P. citri. These negative effects were caused by limonene, a dominant compound in the citrus essential oil. The negative effects of essential oil extracted from nambangan pumello were found to be more pronounced than that from pacitan sweet orange. Concentration of linalool was found to be responsible for the differences, and it worked oppositely with limonene by reducing the negative effects of limonene on P. citri. Essential oil of pacitan sweet orange contained more linalool than pumello. This result gives an alternative technology to control P. citri by using volatile compounds produced by the plant itself with certain composition.

Key words: Essential oil; Sweet orange; Pumello; Panonychus citri; Development;
Reproductive capacity.

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Saturday, October 13, 2007

Pengendalian Hama Penggerek Buah Jeruk

Oleh : Dr.Ir. Mizu Istianto, MT.

Hama penggerek buah jeruk (Citripestis sagittiferela) menyebabkan kerugian cukup besar bagi petani jeruk terutama untuk jeruk manis (sweet orange) dan jeruk besar (pumello). Buah yang terserang hama ini tidak bisa dikonsumsi karena daging buah busuk. Beberapa teknik pengendalian yang ada masih belum memberikan hasil yang memuaskan. Walaupun demikian, telah ditemukan penggunaan bahan penolak (repellent) yang mampu menekan tingkat serangan hama ini. Produk bahan penolak tersebut merupakan formulasi minyak atsiri tumbuhan yang tidak disukai hama ini. Penggunaan bahan penolak ini mampu menekan tingkat serangan antara 60-80%.


Gambar 1. Gejala serangan hama penggerek pada bagian luar buah jeruk besar.
Pelayanan Pengujian Kesehatan Bibit Tanaman Jeruk dan Pisang.

Laboratorium Balai Penelitian Tanaman Buah Tropika mempunyai misi mendukung program penelitian dan pelayanan terhadap pelanggan baik dari dalam maupun luar Balai Penelitian Tanaman Buah Tropika (Balitbu Tropika). Dalam rangka meningkatkan mutu benih yang akan disebar ke masyarakat, salah satu tugas yang diemban adalah melakukan pengujian kesehatan benih. Sebagai tahap awal, saat ini telah dibuka pelayanan pengujian deteksi penyakit kerdil (bunchy top virus) pada tanaman pisang dan citrus tristeza virus (CTV) pada tanaman jeruk . Dengan adanya pengujian tersebut berarti telah dilakukan langka antisipasi untuk mencegah penanaman bibit pisang dan jeruk yang telah mengandung penyakit tersebut.
Saat ini laboratorium Balitbu Tropika sedang menuju proses akreditasi.

Alamat : Balai Penelitian Tanaman Buah Tropika
Jl. Solok-Aripan Km 8 PO.BOX 5 Solok Sumatera Barat
Telp. (0755) 20137.

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Thursday, October 11, 2007

Antracnose Disease

Evaluation of Essential Oils for Antifungal Activity Against Antracnose Disease (Colletotrichum sp) Attacks Banana Fruit in Strorage

By : M. Istianto, Eliza, and C. Hermanto


Indonesian Tropical Fruit Research Institute, PO BOX 5 Solok West Sumatera

for more information e-mail : Ir_Mizu@yahoo.co.id

ABSTRACT

Antracnose, caused by Colletotrichum sp, is important disease that attack banana fruit in storage. The technologies recommended to control antracnose are applying fungicides and heat treatment. Although these fungicides control antracnose effectively, they have negative effect to consumer especially in healthy. Alternative technologies that consider the safety of consumer and environment are needed to replace fungicide application. Essential oils have long been recognized as having good fungitoxic compounds. The aim of this experiment was to understand antifungal activity of essential oils extracted from Cinnamomum bumanni, Cymbopogon nardus, and Citrus grandis against antracnose disease. The experimant was conducted in laboratory of Indonesian Tropical Fruit Resesearch Institute at room temperature. The result showed that essential oils had negative effect to the growth of Colletotrichum sp’s mycelial. Essential oil extracted from C. bumanni had highest inhibition value (65-72%) to the mycelial growth of Colletotrichum sp, followed with inhibition value of C. nardus (62-64%) and C. grandis (14-19%) at last observation. These results showed that essential oil had good potency to be developed as alternative technology that considered consumer and environment safety. The next research to evaluate these essential oil at lower temperature (cold storage) was suggested to be conducted because of distribution banana fruits for long distance usually use cold storage.

[Keywords: essential oils; Cinnamomum bumanni; Cymbopogon nardus; Citrus grandis; Colletotrichum sp; antifungal activity]


(a) (b) (c) (d)

Fig. 1. Mycelial growth of Colletotricum sp treated with essential oil of C. bumanni (a), C. nardus (b), C. grandis (c), and untreated




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Drosophila melanogaster

From Wikipedia, the free encyclopedia

Drosophila melanogaster (from the Greek for black-bellied dew-lover) is a two-winged insect that belongs to the Diptera, the order of the flies. The species is commonly known as the fruit fly, and is one of the most commonly used model organisms in biology, including studies in genetics, physiology and life history evolution. Flies belonging to the Tephritidae are also called fruit flies, which can lead to confusion.

Physical appearance

Wildtype fruit flies have red eyes, are yellow-brown in colour, and have transverse black rings across their abdomen. They exhibit sexual dimorphism: females are about 2.5 millimetres (0.1 inches) long; males are slightly smaller and the back of their bodies are darker. Males are easily distinguished from females based on colour differences (males have a distinct black patch at the abdomen, less noticeable in recently emerged flies (see fig)) and the sexcombs (a row of dark bristles on the tarsus of the first leg). Furthermore, males have a cluster of spiky hairs (claspers) surrounding the anus and genitals used to attach to the female during mating.

There are extensive images at Fly Base.

Life cycle

The developmental period for Drosophila melanogaster varies with temperature, as with many ectothermic species. The shortest development
time (egg to adult), 7 days, is achieved at 28 °C.[2][3] Development times increase at higher temperatures (30 °C, 11 days) due to heat stress. Under ideal conditions, the development time at 25 °C is 8.5 days [4][2][3], at 18 °C it takes 19 days[2][3] and at 12 °C it takes over 50 days.[2][3] Under crowded conditions, development time increases [5], while the emerging flies are smaller[5][6]. Females lay some 400 eggs (embryos), about five at a time, into rotting fruit or other suitable material such as decaying mushrooms and sap fluxes. The eggs, which are about 0.5 millimetres long, hatch after 12–15 h (at 25 °C).[2][3] The resulting larvae grow for about 4 days (at 25 °C) while molting twice (into 2nd- and 3rd-instar larvae), at about 24 and 48 h after eclosion.[2][3] During this time, they feed on the microorganisms that decompose the fruit, as well as on the sugar of the fruit themselves. Then the larvae encapsulate in the puparium and undergo a four-day-long metamorphosis (at 25 °C), after which the adults eclose (emerge).[2][3]

Females become receptive to courting males at about 8-12 hours after emergence.[7] Males perform a sequence of five behavioral patterns to court females. First, males orient themselves while playing a courtship song by horizontally extending and vibrating their wings. Soon after, the male positions itself at the rear of the female's adbdomen in a low posture to tap and lick the female genitalia. Finally, the male curls its abdomen, and attempts copulation. Females can reject males by moving away and extruding their ovipositor. The average duration of successful copulation is 30 minutes, during which males transfer a few hundred very long (1.76mm) sperm cells in seminal fluid to the female[1]. Females store the sperm, which may need to compete with other males' stored sperm to fertilize eggs.

The D. melanogaster lifespan is about 30 days at 29 °C.

Model organism in genetics

Drosophilamelanogaster is the most studied organism in biological research, particularly in genetics and developmental biology. There are several reasons:
  • It is small and easy to grow in the laboratory
  • It has a short generation time (about two weeks) and high fecundity (females can lay >800 eggs in one day)
  • The mature larvae show giant chromosomes in the salivary glands called polytene chromosomes—"puffs" indicate regions of transcription and hence gene activity.
  • It has only four pairs of chromosomes: three autosomes, and one sex chromosome.
  • Males do not show meiotic recombination, facilitating genetic studies.
  • Genetic transformation techniques have been available since 1987.
  • Its compact genome was sequenced and first published in 2000.[8]

Charles W. Woodworth is credited with being the first to breed Drosophila in quantity and for suggesting to W. E. Castle that they might be used for genetic research during his time at Harvard University. Beginning in 1910, fruit flies helped Thomas Hunt Morgan accomplish his studies on heredity. "Thomas Hunt Morgan and colleagues extended Mendel's work by describing X-linked inheritance and by showing that genes located on the same chromosome do not show independent assortment. Studies of X-linked traits helped confirm that genes are found on chromosomes, while studies of linked traits led to the first maps showing the locations of genetic loci on chromosomes" (Freman 214). The first maps of Drosophila chromosomes were completed by Alfred Sturtevant.

Genome

The genome of D. melanogaster (sequenced in 2000, and curated at the FlyBase database[8]) contains four pairs of chromosomes: an X/Y pair, and three autosomes labeled 2, 3, and 4. The fourth chromosome is so tiny that it is often ignored, aside from its important eyeless gene. Its sequenced genome of ~132 million bases has been annotated[8] and contains approximately 13,767 protein-coding genes which comprise ~20% of the genome. More than 60% of the genome appears to be functional non-protein-coding DNA[9] involved in gene expression control. Determination of sex in Drosophila occurs by the ratio of X chromosomes to autosomes, not because of the presence of a Y chromosome as in human sex determination.

Drosophila genes are traditionally named after the phenotype they cause when mutated. For example, the absence of a particular gene in Drosophila will result in a mutant embryo that does not develop a heart. Scientists have thus called this gene tinman, named after the Oz character of the same name (Cf. Azpiazu & Frasch (1993) Genes and Development: 7: 1325-1340.). This system of nomenclature results is a wider range of gene names than in other organisms.

Similarity to humans

About 75% of known human disease genes have a recognizable match in the genetic code of fruit flies (Reiter et al (2001) Genome Research: 11(6):1114-25), and 50% of fly protein sequences have mammalian analogues. An online database called Homophila [2] is available to search for human disease gene homologues in flies and vice versa. Drosophila is being used as a genetic model for several human diseases including the neurodegenerative disorders Parkinson's, Huntington's, Spinocerebellar ataxia and Alzheimer's disease. The fly is also being used to study mechanisms underlying immunity, diabetes, and cancer, as well as drug abuse.

Development

Embryogenesis in Drosophila has been extensively studied, as its small size, short generation time, and large brood size makes it ideal for genetic studies. It is also unique among model organisms in that cleavage occurs in a syncytium.
During oogenesis, cytoplasmic bridges called "ring canals" connect the forming oocyte to nurse cells. Nutrients and developmental control molecules move from the nurse cells into the oocyte. In the figure to the left, the forming oocyte can be seen to be covered by follicular support cells.
After fertilization of the oocyte the early embryo or (syncytial embryo) undergoes rapid DNA replication and 13 nuclear divisions until approximately 5000 to 6000 nuclei accumulate in the unseparated cytoplasm of the embryo. By the end of the 8th division most nuclei have migrated to the surface, surrounding the yolk sac (leaving behind only a few nuclei, which will become the yolk nuclei). After the 10th division the pole cells form at the posterior end of the embryo, segregating the germ line from the syncytium. Finally, after the 13th division cell membranes slowly invaginate, dividing the syncytium into individual somatic cells. Once this process is completed gastrulation starts.

Nuclear division in the early Drosophila embryo happens so quickly there are no proper checkpoints so mistakes may be made in division of the DNA. To get around this problem the nuclei which have made a mistake detach from their centrosomes and fall into the centre of the embryo (yolk sac) which will not form part of the fly.

The gene network (transcriptional and protein interactions) governing the early development of

the fruitfly embryo is one of the best understood gene networks to date, especially the patterning along the antero-posterior (AP) and dorso-ventral (DV) axes (See under morphogenesis).

The embryo undergoes well-characterized morphogenetic movements during gastrulation and early development, including germ-band extension, formation of several furrows, ventral invagination of the mesoderm, posterior and anterior invagination of endoderm (gut), as well as extensive body segmentation [10] until finally hatching from the surrounding cuticle into a 1st-instar larva.

During larval development, tissues known as imaginal discs grow inside the larva. Imaginal discs develop to form most structures of the adult body, such as the head, legs, wings, thorax and genetalia. Cells of the imaginal disks are set aside during embryogenesis and continue to grow and divide during the larval stages - unlike most other cells of the larva which have differentiated to perform specialized functions and grow without further cell division. At metamorphosis, the larva forms a pupae, inside which the larval tissues are reabsorbed and the imaginal tissues undergo extensive morphogenetic movements to form adult structures.

Behavioral genetics and neuroscience

In 1971, Ron Konopka and Seymour Benzer published "Clock mutants of Drosophila melanogaster", a paper describing the first mutations that affected an animal's behavior. Wild-type flies show an activity rhythm with a frequency of about a day (24 hours). They found mutants with faster and slower rhythms as well as broken rhythms - flies that move and rest in random spurts. Work over the following 30 years has shown that these mutations (and others like them) affect a group of genes and their products that comprise a biochemical or biological clock. This clock is found in a wide range of fly cells, but the clock-bearing cells that control activity are several dozen neurons in the fly's central brain.

Since then, Benzer and others have used behavioral screens to isolate genes involved in vision, olfaction, audition, learning/memory, courtship, pain and other processes, such as longevity.

The first learning and memory mutants (dunce, rutabaga etc) were isolated by William "Chip" Quinn while in Benzer's lab, and were eventually shown to encode components of an intracellular signalling pathway involving cylic AMP, protein kinase A and a transcription factor known as CREB. These molecules were shown to be also involved in synaptic plasticity in Aplysia and mammals.

Male flies sing to the females during courtship using their wing to generate sound, and some of the genetics of sexual behavior have been characterized. In particular, the fruitless gene has several different splice forms, and male flies expressing female splice forms have female-like behavior and vice-versa.

Furthermore, Drosophila has been used in neuropharmacological research, including studies of cocaine and alcohol consumption.

Vision

The compound eye of the fruit fly contains 800 unit eyes or ommatidia,
and are one of the most advanced among insects. Each ommatidium contains 8 photoreceptor cells (R1-8), support cells, pigment cells, and a cornea. Wild-type flies have reddish pigment cells, which serve to absorb excess blue light so the fly isn't blinded by ambient light.
Each photoreceptor cell consists of two main sections, the cell body and the rhabdomere. The cell body contains the nucleus while the 100-μm-long rhabdomere is made up of toothbrush-like stacks of membrane called microvilli. Each microvillus is 1–2 μm in length and ~60 nm in diameter.[11] The membrane of the rhabdomere is packed with about 100 million rhodopsin molecules, the visual protein that absorbs light. The rest of the visual proteins are also tightly packed into the microvillar space, leaving little room for cytoplasm.

The photoreceptors in Drosophila express a variety of rhodopsin isoforms. The R1-R6 photoreceptor cells express Rhodopsin1 (Rh1) which absorbs blue light (480 nm). The R7 and R8 cells express a combination of either Rh3 or Rh4 which absorb UV light (345 nm and 375 nm), and Rh5 or Rh6 which absorb blue (437 nm) and green (508 nm) light respectively. Each rhodopsin molecule consists of an opsin protein covalently linked to a carotenoid chromophore, 11-cis-3-hydroxyretinal. [12]

As in vertebrate vision, visual transduction in invertebrates occurs via a G protein-coupled pathway. However, in vertebrates the G protein is transducin, while the G protein in invertebrates is Gq (dgq in Drosophila). When rhodopsin (Rh) absorbs a photon of light its chromophore, 11-cis-3-hydroxyretinal, is isomerized to all-trans-3-hydroxyretinal. Rh undergoes a conformational change into its active form, metarhodopsin. Metarhodopsin activates Gq, which in turn activates a phospholipase Cβ (PLCβ) known as NorpA.

PLCβ hydrolyzes phosphatidylinositol (4,5)-bisphosphate (PIP2), a phospholipid found in the cell membrane, into soluble inositol triphosphate (IP3) and diacylgycerol (DAG), which stays in the cell membrane. DAG or a derivative of DAG causes a calcium selective ion channel known as TRP (transient receptor potential) to open and calcium and sodium flows into the cell. IP3 is thought to bind to IP3 receptors in the subrhabdomeric cisternae, an extension of the endoplasmic reticulum, and cause release of calcium, but this process doesn't seem to be essential for normal vision. [13]

Calcium binds to proteins such as calmodulin (CaM) and an eye-specific protein kinase C (PKC) known as InaC. These proteins interact with other proteins and have been shown to be necessary for shut off of the light response. In addition, proteins called arrestins bind metarhodopsin and prevent it from activating more Gq.

A sodium/calcium exchanger known as CalX pumps the calcium out of the cell. It uses the inward sodium gradient to export calcium at a stoichiometry of 3 Na+/ 1 Ca++.[14]

TRP, InaC, and PLC form a signaling complex by binding a scaffolding protein called InaD. InaD contains five binding domains called PDZ domains which specifically bind the C termini of target proteins. Disruption of the complex by mutations in either the PDZ domains or the target proteins reduces the efficiency of signaling. For example, disruption of the interaction between InaC, the protein kinase C, and InaD results in a delay in inactivation of the light response.

Unlike vertebrate metarhodopsin, invertebrate metarhodopsin can be converted back into rhodopsin by absorbing a photon of orange light (580 nm).

Approximately two-thirds of the Drosophila brain (about 200,000 neurons total) is dedicated to visual processing. Although the spatial resolution of their vision is significantly worse than that of humans, their temporal resolution is approximately ten times better.

Flight

The wings of a fly are capable of beating at up to 220 times per second. Flies fly via straight sequences of movement interspersed by rapid turns called saccades. During these turns, a fly is able to rotate 90 degrees in fewer than 50 milliseconds.

Drosophila, and probably many other flies, have optic nerves which lead directly to the wing muscles (while in other insects they always lead to the brain first), making it possible for them to react extremely quickly.[citation needed]

It was long thought that the characteristics of Drosophila flight were dominated by the viscosity of the air, rather than the inertia of the fly body. However, research in the lab of Michael Dickinson has indicated that flies perform banked turns, where the fly accelerates, slows down while turning, and accelerates again at the end of the turn. This indicates that inertia is the dominant force, as is the case with larger flying animals.[15]

Courtship and mating

When two Drosophila melanogaster of the opposite sex encounter one another, they often first exhibit "cleaning behavior". After this behavior is engaged for some time, the male will proceed towards the rear of the female from either the left or right side. He will then begin a "dance" in which he describes a semi-circle around the female. During this dance the male may or may not vibrate his wings. If the female is not receptive, she will move away and courtship ends. If she is receptive however, the male will approach her rear and make contact with her using his proboscis. The female may then scissor her wings and allow the male to mount. When intercourse, which usually takes about 30 minutes, has finished, the female will dislodge the male with a violent kicking of her hind legs.

References

  1. ^ Meigen JW (1830). Systematische Beschreibung der bekannten europäischen zweiflügeligen Insekten. (Volume 6) (in German). Schulz-Wundermann.
  2. ^ a b c d e f g Ashburner M, Thompson JN (1978). The laboratory culture of Drosophila. In: The genetics and biology of Drosophila. (Ashburner M, Wright TRF (eds.)). Academic Press, volume 2A: pp. 1–81.
  3. ^ a b c d e f g Ashburner M, Golic KG, Hawley RS (2005). Drosophila: A Laboratory Handbook., 2nd ed., Cold Spring Harbor Laboratory Press, pp. 162–4. ISBN 0879697067.
  4. ^ Bloomington Drosophila Stock Center at Indiana University: Basic Methods of Culturing Drosophila
  5. ^ a b Chiang HC, Hodson AC (1950). "An analytical study of population growth in Drosophila melanogaster.". Ecological Monographs 20: 173–206.
  6. ^ Bakker K (1961). "An analysis of factors which determine success in competition for food among larvae of Drosophila melanogaster.". Archives Neerlandaises de Zoologie 14: 200–81.
  7. ^ Pitnick S (1996). "Investment in testes and the cost of making long sperm in Drosophila.". American Naturalist 148: 57–80.
  8. ^ a b c Adams MD, Celniker SE, Holt RA, et al (2000). "The genome sequence of Drosophila melanogaster". Science 287 (5461): 2185–95. PMID 10731132. Retrieved on 2007-05-25.
  9. ^ Halligan DL, Keightley PD (2006). "Ubiquitous selective constraints in the Drosophila genome revealed by a genome-wide interspecies comparison". Genome Res. 16 (7): 875–84. DOI:10.1101/gr.5022906. PMID 16751341. Retrieved on 2007-05-25.
  10. ^ FlyMove website
  11. ^ Hardie RC, Raghu P (2001). "Visual transduction in Drosophila". Nature 413 (6852): 186–93. DOI:10.1038/35093002. PMID 11557987. Retrieved on 2007-05-25.
  12. ^ Nichols R, Pak WL (1985). "Characterization of Drosophila melanogaster rhodopsin". J. Biol. Chem. 260 (23): 12670–4. PMID 3930500. Retrieved on 2007-05-25.
  13. ^ Raghu P, Colley NJ, Webel R, et al (2000). "Normal phototransduction in Drosophila photoreceptors lacking an InsP(3) receptor gene". Mol. Cell. Neurosci. 15 (5): 429–45. DOI:10.1006/mcne.2000.0846. PMID 10833300. Retrieved on 2007-05-25.
  14. ^ Wang T,Xu H,Oberwinkler J,GU Y, Hardie R, Montell C, et al (2005). "Light activation, adaptation, and cell survival Functions of the Na+/Ca2+ exchanger CalX". Neuron 45 (3): 367-378. PMID 15694299.
  15. ^ Caltech Press Release 4/17/2003



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Tuesday, October 9, 2007

MANGGA ARUMANIS 143


Sumber : www.iptek.net.id

Family : Anacardiaceae

Deskripsi

Mangga - yang berasal dari daerah Probolinggo, Jawa Timur - ini merupakan salah satu varietas unggul yang telah dilepas oleh Menteri Pertanian. Buahnya berbentuk jorong, berparuh sedikit, dan ujungnya meruncing. Pangkal buah berwarna merah keunguan, sedangkan bagian lainnya berwarna hijau kebiruan. Kulitnya tidak begitu tebal, berbintik-bintik kelenjar berwarna keputihan, dan ditutupi lapisan lilin. Daging buahnya tebal, berwarna kuning, lunak, tak berserat, dan tidak begitu banyak mengandung air. Rasanya manis segar, tetapi pada bagian ujungnya kadan:gkadang terasa asam. Bijinya kecil, lonjong pipih, dan panjangnya antara 13-14 cm. Panjang buahnya dapat mencapai 15 cm dengan berat rata-rata per buah 450 g. Produktivitasnya cukup tinggi, dapat mencapai 54 kg/pohon.


Manfaat

Sebagai buah meja atau sebagai minuman.

Syarat Tumbuh

Tanaman mangga termasuk tanaman dataran rendah. Tanaman ini dapat tumbuh dan berkembang baik di daerah dengan ketinggian antara 0-300 m di atas permukaan laut. Meskipun demikian, tanaman ini juga masih dapat tumbuh sampai ketinggian 1.300 m di atas permukaan laut. Daerah dengan curah hujan antara 750-2.250 mm per tahun dan temperatur 24-27° C merupakan tempat tumbuh yang baik untuk tanaman buah ini. Jenis tanah yang disukainya adalah tanah yang gembur, berdrainase baik, ber-pH antara 5,5-6, dan dengan kedalaman air tanah antara 50-150 cm.

Pedoman Budidaya

Perbanyakan tanaman: Umumnya, tanaman mangga diperbanyak dengan okulasi, walaupun dapat pula dengan sambung pucuk dan cangkok. Sebagai batang bawah digunakan semai mangga madu, cengkir (indramayu), dan bapang. Penggunaan bibit dari biji tidak dibenarkan, kecuali untuk batang bawah. Batang bawah yang tidak serasi (inkompatibel) berpengaruh kurang baik terhadap pertumbuhan dan pembuahan (produksi buah, bentuk buah, dan rasa daging buah) batang atas. Pembuatan bibit (semaian dan okulasi) biasanya langsung dilakukan di kebun. Kemudian, dipindahkan ke polibag setelah tinggi tunas sekitar 20 cm. Budi daya tanaman: Bibit ditanam dalam lubang tanam berukuran 60 cm x 60 cm x 50 cm dengan jarak tanam 8-12 m. Setiap lubang diberi pupuk kandang yang telah jadi sebanyak 1-2 blek bekas minyak tanah atau 20 kg. Bibit okulasi ditanam di lahan setelah mencapai ketinggian lebih dari 75 cm. Pupuk buatan yang diberikan berupa campuran 200 kg urea, 500 kg TSP (667 kg SP-36), dan 150 kg KCl per hektar atau 200 g urea, 500 g TSP, dan 150 g KCl per tanaman.

Pemeliharaan

Pemupukan dilakukan empat kali dengan selang tiga bulan. Dosisnya meningkat sesuai dengan umur tanaman. Setelah mencapai tinggi 1 m, bibit dipangkas pada perbatasan bidang pertumbuhan agar dapat bercabang banyak. Cabang ini dipelihara 2-3 tunas per cabang. Pemangkasan diulang setelah cabang baru mencapai panjang 1 m, demikian seterusnya hingga diperoleh susunan 1-3-9 cabang.

Hama dan Penyakit

Hama yang merisaukan adalah penggerek batang (Cryptorrhynchus sp.) dan kumbang cicade (Idiocerus niueosparsus). Serangga hama pengisap Idiocerus sangat merusak bunga mangga hingga berguguran. Jumlah bunga betina rendah dengan pembuahan oleh tepung sari yang lemah. Serangan serangga (wereng) menyebabkan produksi mangga rendah. Hama ini dapat diatasi dengan semprotan insektisida sistemik Tamaron 0,2%. Pemberian insektisida melalui infus lebih dianjurkan untuk menghindari pengaruh jelek terhadap kumbang penyerbuknya. Penyakit yang sering menyerang, terutama di daerah beriklim basah adalah penyakit blendok (lh'plodia sp.), mati pucuk (Gloeosporium sp.), dan penyakit pascapanen (Botryodiplodia sp.) yang menyebabkan buah mangga cepat membusuk pada bagian pangkalnya. Namun, penyakit ini dapat menyerang batang sambungan bibit mangga bila kondisi lingkungan tanaman lembap dan dingin. Serangan Diplodia yang sangat merusak batang dapat diatasi dengan mengoleskan larutan Benlate 0,3% atau lisol 20-50% pada luka yang telah dibersihkan lebih dulu.

Panen dan Pasca Panen

Buah mangga dipanen setelah tua benar. Cirinya, bagian pangkal buah telah membengkak rata dan warnanya mulai menguning. Pemungutan buah yang belum tua benar menyebabkan rasanya agak asam dan kelat (mutu rendah). Umur buah dipanen kira-kira 4-5 bulan (110-150 hari) sejak bunga mekar (anthesis). Pemetikan harus hati-hati, tidak boleh jatuh, dan getahnya tidak boleh mengenai buah mangga tersebut. Umumnya, tanaman mangga berbunga pada bulan Juli-Agustus. Buah matang dapat dipanen pada bulan September-Desember. Buah harus dibersihkan dari kutu, jelaga, dan getah yang menempel.

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