No abstract

<p>Biji botani atau TSS (<em>true shallots seed</em>) merupakan salah satu sumber benih bawang merah yang potensial untuk dikembangkan sebagai bahan perbanyakan. Selama ini produksi TSS dilakukan di dataran tinggi. Dataran rendah dengan suhu yang tinggi tidak sesuai untuk menghasilkan pembungaan, namun ada indikasi bahwa dataran rendah menghasilkan pembentukan dan mutu benih TSS yang lebih baik dibandingkan dataran tinggi. Penelitian dilakukan untuk memproduksi benih bawang merah (TSS) di dataran rendah melalui peningkatan pembungaan dan viabilitas serbuk sari menggunakan BAP dan boron. Penelitian dilakukan  di Kebun Percobaan Wera, Subang, Jawa Barat (ketinggian 100 m dpl.), dari Bulan Maret sampai dengan Juni 2012. Rancangan percobaan yang digunakan yaitu acak kelompok faktorial dengan tiga ulangan. Perlakuan terdiri atas dua faktor, yaitu aplikasi benzilaminopurin atau BAP (0, 50, 100, 150, dan 200 ppm) dan boron (0, 1, 2, 3, dan 4 kg/ha). Aplikasi BAP diberikan tiga kali pada umur 1, 3, dan 5 minggu setelah tanam (MST), dan boron pada umur 3, 5, dan 7 MST. Hasil penelitian menunjukkan bahwa pemberian BAP dapat meningkatkan pembungaan dan viabilitas serbuk sari bawang merah, tetapi tidak meningkatkan produksi dan mutu benih TSS di dataran rendah Subang. Aplikasi BAP konsentrasi 50 ppm yang diaplikasikan pada umur 1, 3, dan 5 MST cukup memadai untuk meningkatkan pembungaan bawang merah di dataran rendah Subang. Sementara boron tidak memperbaiki tingkat pembungaan maupun produksi dan mutu benih TSS. Boron 4 kg/ha hanya dapat memperbaiki viabilitas serbuk sari bawang merah. Hasil penelitian ini memberikan informasi bahwa ada peluang untuk memperbaiki tingkat pembungaan yang lebih tinggi di dataran rendah, sedangkan tantangannya ialah peningkatan pembentukan kapsul/buah dan biji TSS.</p>

<p>Kendala produksi benih bawang merah (Allium cepa var. ascalonicum) asal biji atau TSS di dataran rendah adalah rendahnya persentase pembungaan dan pembentukan biji (seed-set.).Untuk meningkatkan pembentukan biji, bawang merah memerlukan suhu 17–19oC. Di Indonesia, suhu udara tersebut hanya terdapat di dataran tinggi&gt;1.000 m dpl.. Percobaan dilaksanakan di Kebun Percobaan Balai Penelitian Tanaman Sayuran (Balitsa) Lembang (1.250 m dpl.) dan di Kebun Percobaan Paseh Subang (100 m dpl.) yang sekaligus merupakan perlakuan percobaan. Penelitian dimulai dari bulan Agustus 2011 sampai Agustus 2012. Tujuan penelitian adalah untuk mempelajari pembungaan, viabilitas serbuk sari, produksi, dan mutu benih TSS di dataran tinggi dan dataran rendah. Pengujian viabilitas serbuk sari serta mutu benih dilakukan di Laboratorium Benih Balitsa Lembang. Hasil penelitian menunjukkan bahwa tingkat pembungaan dan produksi biji di dataran tinggi lebih besar daripada di dataran rendah, sebaliknya mutu benih yang dihasilkan di dataran rendah lebih baik daripada di dataran tinggi. Implikasi penelitian ini adalah dataran tinggi sangat potensial untuk pengembangan produksi biji bawang merah, di mana biji bawang merah dapat menghasilkan umbi bibit yang jauh lebih baik daripada umbi bibit yang beredar di pasar.</p>

Teak ( Tectona grandis L.) is believed to have been introduced from India 400–500 years ago and there appear to be no old-growth natural forests. However, Indonesia has many teak plantation forests and 40%–50% of seeds for reforestation come from seed orchards and the remainder from plantations. In both, flower and fruit abortion results in low fruit set and thus seed production. We investigated flower and fruit development in a clonal seed orchard in East Java in 1999 and 2001 using cross- and open-pollinated trees. The rates of abortion using cross-pollinations showed a similar pattern but were lower than for open-pollinations. The highest rate of abortion in cross- and open-pollinations was during pollination and fertilization, ranging 11%–23% and 31%–32%/day, respectively, less during fruit initiation (5%–6% and 6%–8%/day) and the lowest was during fruit maturation (<0.5%/day). Cross-pollinations increased fruit production by 10-fold compared with open-pollinations. About 30% of flowers were pollinated with an average of five pollen grains per stigma in open-pollinations. Pollen viability varied among clones and time of day but was not affected by position of flowers in an inflorescence. We conclude that low pollination success and low pollen viability are major causes for low fruit production in teak and are related to insect pollinators.

<p>Produksi benih botani bawang merah (true shallot seed/TSS) dapat ditingkatkan melalui peningkatan pembungaan dan intensitas penyerbukan. Aplikasi BAP dapat meningkatkan pembungaan, sementara introduksi serangga penyerbuk dapat meningkatkan intensitas penyerbukan. Tujuan penelitian adalah untuk meningkatkan produksi TSS di dataran rendah Subang (100 m dpl.). Penelitian dilaksanakan dari bulan Juni sampai November 2014. Penelitian terdiri atas dua tahap percobaan. Percobaan pertama disusun dalam rancangan petak terbagi dengan empat ulangan. Petak utama adalah waktu aplikasi BAP yang terdiri dari 1, 3, dan 5 minggu setelah tanam (MST) serta 2, 4, dan 6 MST. Anak petak adalah konsentrasi BAP yang terdiri dari 0, 50, 100, 150, 200, dan 250 ppm. Percobaan kedua dilakukan dengan membandingkan produksi TSS dari dua populasi yang diintroduksi serangga dan tanpa introduksi serangga. Hasil penelitian menunjukkan bahwa aplikasi BAP pada 2, 4, dan 6 MST efektif meningkatkan persentase tanaman berbunga, jumlah bunga per umbel, jumlah kapsul per umbel, persentase pembentukan kapsul per umbel, dan bobot TSS per tanaman. Introduksi Apis cerana efektif meningkatkan jumlah kapsul bernas per tanaman, persentase pembentukan kapsul per tanaman, jumlah TSS per tanaman, persentase TSS bernas per tanaman, dan bobot TSS per tanaman, bobot 100 butir, dan daya berkecambah.</p><p>Production of true shallot seed (TSS) can be increased by enhancing flowering and intensifying the pollination. Application of BAP enhances flowering, whereas introduction of insect pollinator intensifies pollination. This research was aimed to increase TSS production in lowland area of Subang (100 m asl.) and was carried out from June until November 2014. The research consisted of two experiments. The first experiment was arranged in split plot design with four replications. The main plot was time of application of BAP i.e. 1, 3, and 5 week after planting (WAP) and 2, 4, and 6 WAP. The sub plot was consentration of BAP i.e. 0, 50, 100, 150, 200, and 250 ppm. The second experiment was comparing TSS production from two populations with and without installment of Apis cerana hive. The result showed that BAP applied on 2, 4, and 6 WAP effectively increased percentage of plant flowering, number of flower per umbel, number of capsules per umbel, percentage of fruitset, and TSS weight per plant. Introduction of Apis cerana have increased fruitset, percentages of filled TSS, number of TSS per umbel, and TSS weight per umbel as well as weight of 100 seed, and germination capacity.</p>

No abstract

Seed vigour is one of the seed parameters that determines seed quality for successful crop production. An experiment was conducted at Bogor Agricultural University to develop a seed vigour testing method for the true seed of shallot (TSS) using a single count of radicle emergence (RE) that can be used to estimate germination percentage of normal seedlings in the laboratory and field emergence. Nine artificially made seed lots of TSS were used in this experiment which were germinated at two different temperatures i.e., at 20±1℃ and at 25±1℃ (room temperature). The experiments were arranged in a completely randomized design (CRD) with a repeated measurement, having four replicates. The results showed that a single count of RE at 72 and 68 hours germinated at 20±1℃ and 25±1℃ respectively, were able to predict germination percentage in the laboratory 12 days after sowing and field emergence 14 days after planting. Regression and correlation analysis values of RE were predictive to germination percentage with r=0.891 and R 2 =0.951 (p<0.01) for seed lots germinated at 20±1℃ and r=0.924 and R 2 =0.875 (p=<0.01) for seed lots germinated at 25±1℃. Furthermore, RE was predictive to field emergence (FE %) with r=0.953 and R 2 =0.909 (p<0.01) and r=0.865 and R 2 =0.732 (p<0.01) for seed lots germinated at 20±1℃ and 25±1℃ respectively. A single count of RE correlated well with other vigour tests at 68 hours and 72 hours for seed lots germinated at 25±1℃ and/or 20±1℃ respectively, then it can be used as one of the methods for seed vigour test for TSS.

The study was aimed to determine flower initiation, floral morphology and to observe the stages of flowering and fruit development of mindi (Melia azedarch L) within a population for one period of time 2008-2009. The methods used were observing directly over the trees and some vegetatives and generatives buds were sampled for dissecting. The observation revealed that the inflorescence type of mindi was panicle, located at the end of a branch. The number of flower varied among inflorescences, ranged between 30-80 that bloomed simultaneously. The flower was hermaphroditic with position of anther was closed to stigma that selfing might be happened. Usually, the ovary contained 5 ovules that developed into seeds. Reproductive cycle was proceeded for 6-7 months within the year, first observation commenced from flower initiation that occur in August, generative buds to flower burst in September-October. Early fruits were formed in October-November and fruits reached physiological-maturity in January-February. Reproductive success was 34%, indicated that the rate of fertilized ovules proportion to be potencially viable seeds were relatively low.