Judul: Embolisme dan Pertumbuhan Padi Gogo dan Padi Sawah Akibat Cekaman Kekeringan
Abstrak: Embolism is the formation of air bubbles in the xylem vessel of plants caused by drought. Embolism may cause severe plant tissue damage, even lead to plant death. This research aimed to analyze the influence of drought stress to embolism formation and the growth of upland and lowland rice. The experiment was arranged in a factorial randomized complete block design consist of two factors; the first factor was rice variety (Situ Bagendit and Ciherang) and the second factor was drought stress. The results showed that after ten days drought treatment there was a decline of the media and leaves water status. Two types of emboly were formed in the xylem vessel, i.e: circle and ellips emboly. There was no increase in the number and size of circle emboly, whereas the size of ellips emboly was significantly enlarge. The leaves Percentage of Unstained Veins (PUV) of the both rice varieties increased as an effect of drought stress treatments. The increase of emboly did not cause significant difference in all vegetative growth parameters observed, but it was significantly decreased the seed weight of 1000 seeds.
Keyword: upland rice, PUV, lowland rice, embolism, drought stress

Judul: Physiological characteristic of local upland rice from Southwest Sumba Regency under various drought stress conditions
Abstrak: Cekaman kekeringan merupakan salah satu faktor abiotik yang sangat berpengaruh terhadap produktivitas padi. Besarnya penurunan hasil panen akibat cekaman kekeringan dipengaruhi oleh tingkat kepekaan varietas. Penelitian ini bertujuan mengetahui pengaruh berbagai perlakuan cekaman kekeringan terhadap respons fisiologi tumbuhan padi gogo lokal (Gogo Wangi) asal Kabupaten Sumba Barat Daya. Padi Gogo Wangi diberi perlakuan cekaman kekeringan dengan penyiraman 1/2 Kapasitas Lapang (KL) dan 1/4 KL. Sebagai kontrol, padi Gogo Wangi diberi penyiraman dengan 1 KL. Parameter yang diamati adalah komponen karakter vegetatif dan reproduktif, kadar air relatif (KAR), kadar prolin, dan kandungan asam askorbat (ASA) daun. Hasil menunjukkan bahwa cekaman kekeringan menurunkan nilai KAR daun yang berakibat kadar prolin dan kandungan ASA daun meningkat. Cekaman kekeringan juga mempengaruhi tinggi dan bobot kering tajuk, panjang dan bobot kering akar, serta umur berbunga dan panen kedua varietas padi. Namun, cekaman kekeringan tidak mempengaruhi jumlah anakan per rumpun, jumlah daun, jumlah anakan produktif, panjang malai, dan jumlah biji per malai., Drought stress is one of the abiotic factors that decreasing of upland rice productivity. The decreased crop due to drought stress is affected by sensibility level of varieties. The objective of the study was to evaluate physiological responses of local upland rice (Gogo Wangi) from Southwest Sumba Regency under various drought stress conditions. The condition treatments consisted of control with 1 Land Capacity (LC), 1/2 LC, and 1/4 LC watering volume. Observed parameters were vegetative and reproductive characters, leaves relative water content (RWC), proline, and ascorbic acid density. The results showed that drought stress decreased the value of RWC leaves resulting levels of proline and ascorbic acid in leaves increased. Drought stress also significantly affected canopy height and dry weight, root length and dry weight, and days to flower and harvest of two rice varieties. However, drought stress did not affect number of tillers per hill, number of leaves, number of productive tillers, panicle length and number of grains per panicle. Keyword: ascorbic acid, drought stress, local upland rice, proline, Sumba
Keyword: asam askorbat, padi gogo lokal, kekeringan, prolin, Sumba

Judul: Sintesis 1-Kloro-2-metoksi-6-propilnaftalena-1,3-dioksolana (1:1) sebagai Prekursor Asam (S)-(+)-(6-Metoksi-2-naftil)propanoat
Abstrak: Senyawa 1-kloro-2-metoksi-6-propilnaftalena-1,3-dioksolana (1:1) sebagai prekursor asam (S)-(+)-(6-metoksi-2-naftil)propanoat disintesis dari bahan awal 2-metoksinaftalena. Tahapan sintesis diawali dengan klorinasi menggunakan 2 jenis pereaksi klorinasi, yakni isosianurat terklorinasi dan NaOCl. Klorinasi dengan isosianurat terklorinasi berhasil menyintesis 1-kloro-2-metoksinaftalena sebagai produk monoklorinasi melalui pencirian dengan kromatograf gas-spektrometer massa (GC-MS). Nisbah konversi produk paling efisien diperoleh pada laju penambahan 2.5 mmol/jam. Sebaliknya, klorinasi dengan NaOCl menghasilkan produk triklorinasi. 1-Kloro-2-metoksinaftalena selanjutnya diasilasi dengan propanoil klorida, tetapi analisis dengan GC menunjukkan bahwa produk asilasi tidak terbentuk. Sistem bebas-air diperlukan untuk keberhasilan proses asilasi tersebut.
Keyword: isosianurat terklorinasi, NaOCl, nisbah konversi