Post-transcriptional gene silencing (PTGS), an intrinsic plant defense mechanism, can be efficiently triggered by double stranded (ds)RNA-producing transgenes and can provide high level virus resistance by specific targeting of cognate viral RNA. The discovery of virus-encoded suppressors of PTGS led to concerns about the stability of such resistance. Here, we show that Cucumber mosaic virus (CMV) is able to suppress dsRNA-induced PTGS and the associated Potato virus Y (PVY) immunity in tobacco. CMV suppression supported only a transient PVY accumulation and did not prevent recovery of the transgenic plants from PVY infection. CMV inoculation resulted in strongly increased transgene mRNA levels due to suppression of PTGS, but accumulation of PVY-specific small interfering (si)RNA was unaffected. However, PVY accumulation in previously immune plants resulted in increased PVY siRNA levels and transgene mRNA was no longer detected, despite the presence of CMV. Transgene mRNA returned to high levels once PVY was no longer detected in CMV-infected plants. Recovered and chronically CMV-infected tissues were immune to further PVY infection.

No abstract

G The first two authors contributed equally to this work.Abstract. We have characterised six Australian Cucumber mosaic virus (CMV) strains belonging to different subgroups, determined by the sequence of their complete RNA 3 and by their host range and the symptoms they cause on species in the Solanaceae, Cucurbitaceae and on sweet corn. These data allowed classification of strains into the known three CMV subgroups and identification of plant species able to differentiate the Australian strains by symptoms and host range. Western Australian strains 237 and Twa and Queensland strains 207 and 242 are closely related members of CMV subgroup IA, which cause similar severe symptoms on Nicotiana species. Strains 207 and 237 (subgroup IA) were the only strains tested which systemically infected sweet corn. Strain 243 caused the most severe symptoms of all strains on Nicotiana species, tomato and capsicum and appears to be the first confirmed subgroup IB strain reported in Australia. Based on pair-wise distance analysis and phylogeny of RNA 3, as well as mild disease symptoms on Nicotiana species, CMV 241 was assigned to subgroup II, as the previously described Q-CMV and LY-CMV.

<p>ABSTRACT<br />Ketahanan tanaman terhadap serangga hama berdasarkan karakter<br />morfologi bulu (trichom) pada daun merupakan salah satu cara potensial<br />mengurangi penggunaan insektisida kimia dalam pengendalian hama.<br />Serangga hama pengisap Bemisia tabaci pada tanaman kapas juga dapat<br />dikendalikan dengan menggunakan varietas kapas resisten berdasarkan<br />karakter morfologi bulu daun. Penelitian peranan kerapatan bulu daun<br />pada tanaman kapas terhadap kolonisasi B. tabaci Gennadius dilakukan di<br />Kebun Percobaan Pasirian, Kabupaten Lumajang, dan di Laboratorium<br />Entomologi Balai Penelitian Tanaman Tembakau dan Serat Malang, mulai<br />April hingga Juli 2005. Tujuan penelitian adalah untuk mengetahui<br />peranan kerapatan bulu daun pada beberapa aksesi plasma nutfah kapas<br />terhadap kolonisasi B. tabaci. Perlakuan terdiri atas 11 aksesi plasma<br />nutfah kapas yang dipilih berdasarkan penilaian visual pada karakter<br />kerapatan bulu daun yang mewakili kerapatan bulu rendah hingga tinggi,<br />yaitu: (1) KK-3 (KI 638), (2) Kanesia 1 (KI 436), (3) A/35 Reba P 279 (KI<br />257), (4) Acala 1517 (KI 174), (5) Asembagus 5/A/1 (KI 162), (6) 619-<br />998xLGS-10-77-3-1 (KI 76), (7) DP Acala 90 (KI 23), (8) TAMCOT SP<br />21 (KI 6)), (9) Kanesia 8 (KI 677), (10) CTX-8 (KI 494), dan (11) CTX-1<br />(KI 487). Penelitian disusun dalam rancangan acak lengkap (RAL) dengan<br />10 ulangan. Paramater yang diamati adalah jumlah bulu daun, telur dan<br />nimfa pada 1 cm2 luas daun, serta jumlah imago B. tabaci pada daun<br />ketiga dari atas tanaman. Hasil penelitian menunjukkan bahwa kerapatan<br />bulu daun berkorelasi positif dengan kolonisasi B. tabaci (R=0,9701).<br />Semakin tinggi kerapatan bulu daun, semakin meningkat kolonisasi B.<br />tabaci. Kolonisasi B. tabaci lebih tinggi pada CTX-1, CTX-8, Kanesia 8,<br />dan KK-3 (150-250 individu/cm 2 luas daun) karena tingkat kerapatan bulu<br />daun juga lebih tinggi (150-300 helai/cm 2 luas daun) dibanding TAMCOT<br />SP 21, DP Acala 90, 619-998xLGS-10-77-3-1, Asembagus 5/A/1, Acala<br />1517, A/35 Reba P 279, dan Kanesia 1 yang memiliki kerapatan bulu daun<br />(0-100 helai/cm 2 luas daun) dan tingkat kolonisasi B. tabaci (&lt;100<br />individu/cm 2 luas daun) lebih rendah.<br />Kata kunci : Kapas, Gossypium hirsutum, plasma nutfah, hama, Bemisia<br />tabaci, trichom, kolonisasi, Jawa Timur</p><p><br />ABSTRACT<br />Role of trichome density of cotton leaf to colonization of<br />Bemisia tabaci Gennadius<br />Trichome-based host plant resistance offers the potential to reduce<br />chemical insecticides used in insect pest control. Cotton whitefly, Bemisia<br />tabaci can be controlled by using resistant variety based on trichome<br />density as plant morphological characteristics. The study on the role of<br />trichome density of cotton accessions on the colonization of B. tabaci was<br />carried out at Pasirian Experimental Station at Lumajang, and at<br />Entomology Laboratory of Indonesian Tobacco and Fiber Crops Research<br />Institute (IToFCRI ) in Malang from April to July 2005. Treatments<br />included 11 cotton accessions, viz. (1) KK-3 (KI 638), (2) Kanesia 1 (KI<br />436), (3) A/35 Reba P 279 (KI 257), (4) Acala 1517 (KI 174), (5)<br />Asembagus 5/A/1 (KI 162), (6) 619-998xLGS-10-77-3-1 (KI 76), (7) DP<br />Acala 90 (KI 23), (8) TAMCOT SP 21 (KI 6)), (9) Kanesia 8 (KI 677),<br />(10) CTX-8 (KI 494), and (11) CTX-1 (KI 487). The experiment was<br />arranged in completely randomized design with ten replications.<br />Parameters observed were trichome density, number of eggs and nymphs<br />on one cm2 of leaf and adult of B. tabaci on 3rd highest leaf of cotton<br />plant. The result showed that trichome density was positively correlated<br />with B. tabaci colonization (R=0,9701) in which higher trichome density<br />of cotton leaf has resulted in great colonization of B. tabaci. Bemisia<br />tabaci colonisation was higher on CTX-1, CTX-8, Kanesia 8, and KK-3<br />(150-250 individu/cm2 of leaf) due to dense trichome (150-300<br />trichomes/cm2 leaf) as compared with other accessions, viz. TAMCOT<br />SP 21, DP Acala 90, 619-998xLGS-10-77-3-1, Asembagus 5/A/1, Acala<br />1517, A/35 Reba P 279, and Kanesia 1 which showed less density of leaf<br />trichome (0-100 trichomes/cm2 of leaf) and B. tabaci colonization (&lt; 100<br />individu/cm2 of leaf).<br />Key words : Cotton, Gossypium hirsutum, cotton accession, pest,<br />Bemisia tabaci, trichome, colonization</p>

<p>ABSTRAK<br />Daerah pengembangan kapas di Indonesia umumnya lahan kering<br />dengan keterbatasan air. Penelitian ini bertujuan untuk mendapatkan galur-<br />galur kapas toleran kekeringan menggunakan PEG-6000 pada fase<br />kecambah. Penelitian dilaksanakan di Laboratorium Pengujian Benih Balai<br />Penelitian Tanaman Pemanis dan Serat, mulai bulan April sampai Juni<br />2012. Perlakuan disusun dalam rancangan Petak Terbagi dan diulang dua<br />kali. Petak utama adalah perlakuan PEG-6000 (-3 bar) dan tanpa PEG-<br />6000 (air), sedangkan anak petak adalah 13 galur kapas dan varietas<br />Kanesia 14. Setiap perlakuan terdiri dari lima pot masing-masing ditanam<br />sepuluh biji. Benih kapas dicampur dengan fungisida Mancozeb 80% 2<br />g/kg benih sebelum ditanam. Parameter pengamatan meliputi daya<br />berkecambah, panjang kecambah dan akar, bobot kecambah dan akar,<br />rasio  panjang  akar/kecambah,  serta  indeks  kerentanan  terhadap<br />kekeringan. Kecambah dihitung sebagai kecambah normal jika panjang<br />lebih dari 0,5 cm. Perlakuan PEG-6000 berpengaruh sangat nyata terhadap<br />penurunan daya berkecambah, panjang kecambah dan akar, serta bobot<br />kecambah dan akar. Sebaliknya, rasio panjang akar/kecambah lebih tinggi<br />pada perlakuan PEG-6000 dibandingkan dengan perlakuan tanpa PEG-<br />6000. Respon ketahanan galur kapas yang dihitung dengan indeks<br />kerentanan kekeringan berbeda pada masing-masing parameter yang<br />diamati. Dari nilai rata-rata indeks kerentanan kekeringan semua<br />parameter, tidak ada galur yang tahan terhadap kekeringan (S&lt;0,50).<br />Terdapat delapan galur yang agak tahan kekeringan (0,50&lt;S&lt;1,0) dan<br />lebih tahan dibandingkan dengan Kanesia 14, yaitu 03002/12, 03006/1,<br />03008/7, 03008/24, 03012/17, 03014/12, 03017/13, dan 03017/15.<br />Kata kunci: Gossypium hirsutum L., tahan kekeringan, PEG-6000,<br />perkecambahan, galur</p><p>ABSTRACT<br />Cotton production areas in Indonesia are arable land with lack of water<br />availability. The aim of this study was to obtain cotton lines tolerant to<br />drought using PEG-6000 at germination stage. The experiment was<br />conducted at the Seed Testing Laboratory in Indonesian Sweetener and<br />Fiber Crops Research Institute, from April to June 2012. Treatments were<br />arranged in a Split Plots design with two replications. The main plot was<br />PEG-6000 (-3 bar) and without PEG-6000 (water), while the subplot was<br />13 cotton lines and Kanesia 14 variety. Seed cotton was treated with 80%<br />Mancozeb fungicide dose of 2g/kg seed before sowing. Parameters<br />observed were germination percentage, shoot and root length, shoot and<br />root weight, ratio of root/shoot length, and drought susceptibility index.<br />Seedling was counted as normal if its length more than 0.5 cm. PEG-6000<br />treatment gives very significant effect on the decline on seed germination,<br />shoot and root length, shoot and root weight. Otherwise, ratio of root/shoot<br />length was higher in the PEG-6000 than without PEG-6000 treatment.<br />Response of cotton lines to drought which calculated with a drought<br />susceptibility index were different among parameter observed. Mean<br />drought susceptibility index of all parameters showed that none of cotton<br />line tolerant to drought (S &lt; 0,50) was achieved from the study. There<br />were eight moderately drought-resistant lines (0, 50 &lt; S &lt; 1,0) achieved<br />namely 03002/12, 03006/1, 03008/7, 03008/24, 03012/17, 03014/12,<br />03017/13, and 03017/15 which more resistance than Kanesia 14.<br />Key words: Gossypium hirsutum L., drought tolerant, PEG-6000,<br />germination, lines</p>

<p><span style="font-size: medium;">ABSTRAK </span></p><p>Keragaman komponen seleksi yang berpengaruh terhadap kecepatan berbunga dan produksi buah kelapa Genjah Salak <br /> belum banyak diketahui. Penelitian bertujuan mendapatkan metode penyerbukan dalam peningkatan produktivitas <br /> kelapa Genjah Salak dengan menghitung heritabilitas tiga belas karakter vegetatif dan generatif yang berkaitan langsung <br /> atau tidak langsung dengan produksi buah. Penelitian dilakukan di Kebun Percobaan Paniki, Manado, Sulawesi Utara, <br /> dari 2011 sampai 2014, menggunakan rancangan acak kelompok, tiga perlakuan dan empat ulangan.  Perlakuan terdiri <br /> atas tiga sistem penyerbukan, yaitu penyerbukan sendiri (full sib), penyerbukan terkendali (half sib) dan penyerbukan <br /> alami (open pollination). Tiga belas karakter yang diukur adalah tinggi batang, lingkar batang, jumlah bekas daun, jumlah <br /> daun, panjang daun, panjang petiole, jumlah anak daun, panjang anak daun, jumlah tandan, jumlah spikelet, jumlah <br /> bunga betina, kecepatan berbunga, dan jumlah buah per tandan. Analisis heritabilitas menggunakan rumus Singh dan <br /> Chaudary. Analisis sidik lintas mengacu pada metoda matriks Singh dan Chaudary. Kelapa Genjah Salak dengan sistem <br /> penyerbukan sendiri memiliki waktu berbunga 34,74 bulan dan tinggi batang 51,75 cm, lebih baik dibandingkan dengan <br /> kelapa Genjah Salak yang menyerbuk terkendali (waktu berbunga 35,99 bulan; tinggi batang 52,51 cm) dan penyerbukan <br /> alami (waktu berbunga 36 bulan; tinggi batang 56,76 cm). Nilai heritabilitas pada kelapa Genjah Salak menyerbuk <br /> sendiri yang berkorelasi langsung dengan karakter hasil adalah tinggi batang (r = 0,383; h2 = 84,0%), jumlah bekas daun <br /> (r = 0,442; h2 = 63,0 %), dan jumlah bunga betina (r = 0,344; h2 = 75,0%).  Metode terbaik untuk meningkatkan produk-<br /> tivitas kelapa Genjah Salak adalah dengan sistem penyerbukan sendiri karena memiliki nilai heritabilitas tinggi dan <br /> berkorelasi langsung dengan karakter hasil.</p><p>Kata kunci: Heritabilitas, koefisien sidik lintas, sistim penyerbukan, kelapa Genjah Salak.</p><p> </p><p>Heritability and Path Analysis on Vegetative and Generative Characters of Salak Dwarf Coconut Generated from Three Pollination System  </p><p><span style="font-size: medium;">ABSTRACT </span></p><p>The diversity of Salak Dwarf components that can be used as a criterion of selection affecting the rate of flowering and yield have not been investigated. The research aims to obtain the best method of pollination in improvement of Salak dwarf coconut productivity by calculating the heritability of thirteen vegetative and generative characters. Twelve characters attributed to the production of fruits were investigated.  The research was arranged in a randomized block design with three pollination system as the treatments, four replications, conducted at the Paniki Experimental Garden, North Sulawesi, from 2011 until 2014.  Treatments consisted of self-pollination system (full sib), controlled pollination system (half sib) and open pollination system. Thirteen characters measured were stem height, girth of stem, number of leaf scars, number of leaves, leaf length, petiole length, number of leaflets, length of leaflet, number of bunches, number of spikelet, number of female flowers, day of flowering, and number of fruit per bunch. Analysis of heritability using the formula of Singh and Chaudary. Path coefficient analysis using matrix model by Shing and Chaudary. Salak dwarf coconut with self-pollination system has better effect of  rate of flowering (34.74 month), and height of stem (51.75 cm) compared to the salak dwarf coconut with controlled pollination (rate of flowering 35.99 months; height of stem 52.51 cm) and Salak dwarf coconut with open pollination (rate flowering 36 months; height of stem 56.76 cm). To improve the productivity of Salak dwarf coconut, the best method of pollination is self-pollinated.  Heritability value on self-pollinate of Salak dwarf coconut which correlates directly with the character of yield was the height of stem (r =0.383; h2=84.0%),  the number of leafscars (r =0.442; h2=63.0%), and the number of female flowers (r =0344; h2=75.0%). The best method to increase the productivity of Salak dwarf coconut through self pollination since it has high heritability values and correlates directly with the character of yield.</p>Keywords : Heritability, coefficient of path analysis, pollination systems, salak dwarf coconut.

Spores of vesicular arbuscular mycorrhizal (VAM) fungi contain thousands of nuclei. In order to understand the karyotic structure of a VAM fungus spore, the genetic variation of the first generation of spores from a VAM fungus (Gigaspora margarita) was examined. Spores originating from both single-and multispore inoculations of the species G. margarita were analyzed by M13 minisatellite-primed PCR. In both cases, different fingerprints were obtained from individual spores with few spores exhibiting similar fingerprints. These results can be explained only by a heterokaryotic status of the nuclear population within a spore.

<p>ABSTRAK</p><p>Tanaman kapas dengan bentuk daun yang menjari (okra) diharapkanbisa dikembangkan dengan sistem tanam rapat untuk meningkatkan hasilkapas berbiji. Penelitian lapang dilakukan di Kebun Percobaan Asem-bagus, Situbondo, Jawa Timur mulai Februari-Juli 2007 dan bertujuanuntuk mengetahui kesesuaian galur kapas berdaun okra pada sistem tanamrapat. Sistem tanam rapat yang dimaksud adalah sistem tanam monokulturdengan jarak tanam dalam barisan dirapatkan yaitu dengan jarak tanam100 cm x 10 cm (100.000 tan/ha). Percobaan disusun dalam rancanganacak kelompok dengan 3 ulangan dan 1 ulangan monokultur dengan sistemtanam normal (100 cm x 25 cm; 40.000 tan/ha). Perlakuan terdiri dari 14galur/varietas kapas yang terdiri atas 12 galur berdaun okra dan 2 varietasberdaun normal (Kanesia 8 dan Kanesia 13) sebagai pembanding.Paramater yang diamati adalah tinggi tanaman, lebar kanopi, jumlahcabang generatif, jumlah buah/tanaman setiap bulan mulai 60-120 HST.Bobot buah, jumlah buah terpanen dan hasil kapas berbiji diamati saatpanen. Hasil penelitian menunjukkan bahwa peningkatan populasi tanam-an menurunkan jumlah cabang generatif, jumlah buah dan bobot buah pertanaman. Semua galur okra yang dicoba pada sistem tanam rapat rata-ratahanya meningkatkan hasil kapas berbiji 2,12% dibanding pada populasinormal. Rata-rata hasil kapas berbiji galur okra pada populasi rapat adalah2.315,8 kg/ha dan pada populasi normal 2.293,2 kg/ha. Selanjutnya hasilkapas berbiji berdaun normal Kanesia 8 dan Kanesia 13 pada populasirapat masing-masing 2.159 dan 2.179 kg/ha dan pada populasi normal1.983 kg/ha dan 2.525 kg/ha. Galur okra 98040/3 dan 98048/2 menghasil-kan produksi tertinggi pada populasi rapat (masing-masing 2.640 kg/hadan 2.627 kg/ha) dan pada populasi normal (2.688 kg/ha dan 2.807 kg/ha).Kedua galur okra tersebut mempunyai potensi hasil yang lebih tinggidibanding kapas berdaun normal (Kanesia 8 dan Kanesia 13) baik padapopulasi rapat maupun populasi normal.</p><p>Kata kunci: Gossypium hirsutum L., tanam rapat, daun okra</p><p>ABSTRACT</p><p>Suitability of Cotton Lines with Okra Leaves UnderNarrow Interrow SpacingOkra leaf cotton crop may have a potential increase in the seedcotton yield under narrow inter row spacing. Okra leaf cotton lines weretested in relative performance under high interrow spacing. The field trialwas conducted at the Asembagus Experimental Station, Situbondo, EastJava from February to July 2007. Okra leaf cotton lines were planted asmonocrop with plant spacing of 100 cm between rows and 10 cm withinrows (100,000 plants/ha). Experiment was arranged in a randomized blockdesign with three replicates. In addition, one plot was allocated formonocrop with normal inter row spacing (100 cm between rows and 25 cmwithin rows; 40,000 plants/ha). Fourteen selected cotton lines consistingof 12 lines with okra leaf and 2 varieties (Kanesia 8 and Kanesia 13) withnormal leaf as check varieties were tested. Cotton plant height, canopywidth, number of fruiting branches, and boll/plant were measured monthlyfrom 60-120 dap. Boll weight, number of harvested bolls, and seed cottonyield were counted at harvesting. Results showed that increased plantdensity resulted in reduced fruiting branches, boll count, and boll weight.The okra leaf cotton under high crop density system showed a yieldincrease by 2.12% compared to normal spacing. Average seed cotton yieldunder narrow interrow spacing was 2,315.8 kg/ha and the average yieldunder normal interrow spacing was 2,293.2 kg/ha. Okra lines cotton98040/3 and 98048/2 showed the highest yield under narrow interrowspacing (2,640 and 2,627 kg/ha) and under normal interrow spacing (2,688kg/ha dan 2,807 kg/ha). Both lines offered higher yield than those withnormal leaf under high interrow spacing and normal population.</p><p>Key words: Gossypium hirsutum L., high interrow spacing, okra leaf</p>